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#1
Tuesday, January 10, 2012
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Geography Notes by Muhammad Kashif Aslam (33rd CTP PSP)
Objective:-
c. Growth of Population d. All of these. 2. Simple conical projections with one standard parallel are used for: a. Maps for higher latitudes b. Maps for Polar Regions c. Maps for lower latitudes d. None of these.
c. denotes a low rainfall zone d. None of these.
c. Areas of Moderate extent d. None of these.
c. Temperature latitudes d. None of these.
b. Medium scale map d. None of these.
c. 2.85 and 3.75 d. None of these
c. Eighteenth Century d. None of these
c. Cadastral maps d. None of these
c. Dot method d. None of these
c.. d……. none of these
c. 27.3% d. None of these
c. 10 to 20 degrees N and S d. None of these 18. The oldest known map projection is: a. Gnomonic b. Bonne’s c. Simple Cylindrical d. None of these
a. 1 ¼ km b. 1 ½ km. c. 2 ¼ km d. 2 ½ km
c. Isopleths d. Bar graph e. pie graph
d. 250 m e. 300 m
c. frontal d. Land breeze
c. zenithal d. conventional e. mercator’s
a. Choropleth b. Isopleths c. Both 33. The distribution of population in a map is best represented by: d. Dot symbol e. Bar graph f. Pie graph 34. The method of transferring lines of latitude and longitude from the globe to a Plane surface is called: a. Cylindrical Projection b. Map projection c. Luxodrome 35. The distribution of daily atmospheric conditions of an area is shown in a : a. Distribution map b. Weather map c. Both 36. Point symbols and Line symbols are used in the preparation of: a. Weather maps b. Distribution maps c. Both 37. Distributional maps are based on : a. Statistical data b. Descriptive information c. Empirical observations 38. The best method of actual distribution of population: a. Dot method b. Shade method c. Comparative divided circles 39. Average monthly temperature of a place can be represented by means of: a. Bar graph b. Line graph c. Pie-graph 40. If you are asked to draw a map of an area showing the distribution of a Population you will make use of: a. Point symbol b. Line symbol c. Area symbol 41. For mapping a vast temperate region the best suited projection is: a. Conical with one standard parallel b. Conical with two standard parallels c. Moll-weide 42. To show the distribution of temperature (mean monthly) of a station the best Method is: a. Line graph b. Bar graph c. Histogram 43. For drawing maps of Polar Regions, an ideal map projection would be: a. Zenithal equal-area b. Sanson-Flamsteed c. Mercator d. None of the above 44. A straight line joining Islamabad with Mecca Moazzema is the true direction Of Quibla from the former city on a map drawn on: a. International projection b. Mercator’s projection c. Simple Cylindrical projection 45. The map projection suited for the world map showing wind direction is : a. Cylindrical equal-area b. Mercator’s c. Conical projection 46. Thermal equator is located: a. At the equator b. North of equator c. South equator d. None of these 47. Density of sea water ranges from : a. 1.027 to 1.028 b. 1.010 to 1.025 c. 1.000 to 1.020 d. None of these e. 1.020 to 1.029 48. The material thrown out during an eruption is: a. Solid b. Liquid c. Gaseous d. All of these. 49. The cold air mass is : a. Conditionally unstable b. Stable c. Unstable d. None of these 50. In a wave water particles move only: a. Near the coast b. In deep water c. In shallow water d. None of these 51. The inner core of the earth is : a. Solid b. Liquid c. Semi solid d. None of these 52. The flat ocean bottom lying near the continents is called: a. Peneplain b. archipelagic apron c. Lacustrine plain d. None of these 53. The water that trickles down the side of the Cave deposits Carbonate of lime In layers is called: a. Stalagmite b. Dolomite c. Stalactite d. None of these 54. Pene plains are the type of : a. Coastal Plains b. Depositional Plains c. Erosional Plains d. None of these 55. According to Krummel water covers……….of the globe: a. 70.8% b. 71.7% c. 71.8% d. None of these 56. The Pacific Ocean is roughly …….... in shape: a. Conical b. Triangular c. Circular d. None of these 57. The seismic sea wave form travels at speed of …….Per hour a. 200 to 300 km b. 500 to 800 km c. 350 to 450 km d. None of these d. 600 to 800 km 58. The centre of moon is about ……..Miles from the centre of the earth: a. 240,000 miles b. 236,000 miles c. 238,000 miles d. None of these d. 238,857 miles 59. Globigerina ooz is made up chiefly of : a. Frustules b. Foraminifera c. Silica d. None of these 60. Marble and Hornfelses are produced as a result of : a. Contact metamorphism b. Regional metamorphism c. Dynamic metamorphism d. None of these 61. Notable river with estuary is : a. Volga b. Indus c. Amazon d. None of these 62. Conditions most favorable to solifluction are found in: a. Deserts b. Equational region c. Permafrost region d. None of these 63. Tombolo Spit connects : a. Reef with Island b. Island with headland c. Lagoon with Cliff d. None of these 64. Pluto was discovered in: a. 1840 b. 1930 c. 1970 d. None of these 65. Deepest of all known oozes is : a. Diatomaceous b. Globigrina c. Radiolarian d. None of these 66. Bore is caused by : a. rising tide while meeting river currents b. friction from prevailing winds c. spring tide and strong winds d. unequal heating of oceans 67. Biological weathering occurs in the ways except: a. joint widening by roots b. honeycomb weathering c. reaction with humic acid d. reaction with plant and animal solution 68. Which of these is process of transportation in a river? a. solution b. corrasion c. attrition d. deposition 69. A canyon is a large form of : a. dry valley b. gorge c,. Pediment d. badland 70. Mediterranean regions are useful for all these except: a. tourism b. forestry c. fruit growing d. wine production e. wheat growing
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Success is never achieved by the size of our brain but it is always achieved by the quality of our thoughts. 
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#2
Tuesday, January 10, 2012
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Characteristics and problems of urban places:
CHARACTERISTICS AND PROBLEMS OF URBAN PLACES:
1. FIXED TRANSIT ON ALL SECODARY CORRIDORS: Fixed-rail transit helps to guide development and keep the streets busy. When development happens around fixed-transit, it is easy to get around on foot because everything is closer together. On the contrary, when transit isn't fixed, as with a diesel bus route, or it is designed around the auto, transit becomes impractical because everything is further apart. New York is an example of a walking city that grew up around fixed transit. Dallas is an example of an auto city built up around roadways. It is very convenient to get around without a car in a walking city built around fixed transit. This makes it so there are more people on the sidewalks, and businesses can thrive from walking traffic, without the need for parking. Fixed-transit can be light-rail, a subway, or a bus that operates from overhead wires. A bus way built for diesel buses is also fixed transit, but because the bus can leave the bus way it doesn't have the same positive impact on development and density as other forms of fixed transit. 2. MIXED-USE NEIGHBORHOOD: Mixed-use neighborhoods solve many urban ills. By intermingling commercial, residential, and civic functions in the same neighborhoods, you reduce dependence on automotive transport, since destination facilities are always close at hand: one can walk to the market, the salon, the library, school or university, administrative offices, what have you. This means denser development is possible without reducing living spaces; it also means more tax money for more amenities and social programs, since streets don't pay taxes and parking lots don't pay much tax, but homes and businesses do. Yet, since there is less road infrastructure to build and maintain, and utility infrastructure is more efficiently configured, such neighborhoods need less tax money to support their basic functions. This means one could then either lower taxes, or applies them to more desirable civic amenities, such as parks, squares, concerts, etc. More people walking also increases community feeling, reduce opportunity for crime, and allows for more interaction among the citizenry. It increases rider ship on public transit, making it more efficient. 3. MIXED-INCOME NEIGHBORHOOD: Mixed-income neighborhoods not only increase urban variety by mixing types and sizes of housing; they also increase the cohesiveness of a community. People from different walks of life come to meet and know each other, however superficially, and are thus less likely to make political or personal decisions based on stereotyped views. Rich, poor, and middle can discover common ground and not base their attitudes toward each other on envy, disdain, or spite. It's a matter of hybrid vigor: purebred ideas, like purebred animals, tend to be delicate, weak, and subject to "genetic" infirmities. We learn not by congregating with those similar to us, but by meeting those who are different. You could say it's the sexuality of the intellect: just as animals who exchange genes evolve into more efficient forms more rapidly than those primitive creatures that don't, so do societies whose members exchange ideas, social concepts, personal philosophies, what have you--even just gossip. 4. BUILDING OF DIFFERENT AGE, CONDITION AND SIZE: Too often in the last half-century urban developers and city officials have approached revitalization by assembling multiple parcels, bulldozing what existed, and building new. This happens in commercial and residential areas. It is standards set by suburban development and a desire to compete with suburban development that leads to this practice. This will not, however, lead to a healthy city. The mix of old and new buildings provides an interesting streetscape. Older building in poor condition provides the incubators for entrepreneurs to start businesses. The newer buildings provide locations for the more established merchants to set up shop and serve as drawing cards for a business district. The mix also serves to provide residential dwelling units of different size, condition and price making it so the neighborhood is mixed economically and providing places for both the business owner and grocery clerk to live. 5. LIVING PLACES: Many cities that developed after World War II or were redeveloped after World War II mirror suburbs in that there are some areas where people live, others where people shop and others where people work. This leads to people moving in mass at different times of the day from one area to the other. This creates needless congestion, streets empty at some times and overcrowded at others. When the places people live are spread throughout the city, many will choose to live near where they work. Stores will locate where people live. Many small stores will serve to supplement or even replace larger stores. 6. MOVEMNET OF PEOPLE (MOVING IN FROM OTHER PLACES, NAD MOVING OUT TO OTHER PLACES: A city is more than just a collection of people. It is an incubator of ideas. Certain stability is good for a city, but an influx and out box is even more important. The best cities pull people from far away places. This brings together the widest array of ideas, interests and backgrounds. As important as it is for cities to attract diverse people from far away places, it is important to send them out again. Cities, especially industrial ones suffering from a loss in population often lament the loss of residents who leave. This sending out of your product and the transplanting of native people is also productive and leads to other cities being healthy and energetic places. It can also lead to economic growth when a person with a background in say metal fabricating leaves and initiates activities elsewhere or gains knowledge that will improve processes or establish new markets. People leaving a city sends out messengers with the knowledge needed to make it part of activities elsewhere. 7. AMELIORATION TEMPERATURE EXTREMES: Trees and gardens save energy and money and give pleasure to people, living space to animals and birds. Rooftop gardens provide better insulation than any amount of fiberglass batting and can grow food as well; trees provide shade in the summer and obligingly drop their leaves in the winter so sunlight can warm homes and offices, and their transpiration also helps balance local temperatures and reduce need for HVAC.. 8. FARMS WITHIN VITY LIMITS: The farther food is grown from town, the more it costs and the worse it tastes. Local farming means less fuel and road use, which is good for the earth and reduces need for taxes to support road infrastructure and fuel subsidies. Shorter transport times means food can ripen longer on the branch, so it tastes better and is more nutritious. The necessity to fit farms into numerous smaller spaces in town means fewer big agribusiness operations making their money on economies of scale; instead you have a greater number of small producers, which would lead to more variety of food, more accommodation to local tastes, and more competition (thus better service and lower prices), as well as making commercial organic farming economically feasible. This would again reduce stress on the earth and help minimize dependence on petroleum. Urban farmers' markets bear all this out, providing higher quality food than the supermarkets, yet charging less for it. Also, the presence of farms provides green space for the citizens and reminds them that all, regardless of pretensions, are tied to the earth. 9. SHOPS THAT OPEN ONTO THE SIDE-WALK AND UNDERGROUND PARKING: Shops that open onto the sidewalk encourage pedestrian traffic, and pedestrians are better able to window shop than drivers. Walking of course is exercise too, and people who are walking are more likely to meet or make friends or other social, even commercial, contacts than drivers can. More pedestrian traffic therefore makes for a healthier and richer city. Shops set back behind vast parking lots foster the delusion that they are separate from the city and bear no responsibility to the community that supports them. They practically require driving, which increases civic infrastructure costs and increase social isolation. Sidewalk shops encourage friendly social contact and simply make life more pleasant. Putting parking in mid-block structures or (better yet) underground accommodates those who must or prefer to drive without fragmenting the city to make room for vast parking lots. 10. COMMUNICATION: Spatial organization within the city is often based on what business or groups have to communicate with one another. Changes in communication have drastically altered both the internal structure of the city and how cities are related to one another. Similarly within the city, banks, title companies, law offices and so on had to be close together so that documents could be transmitted quickly and easily. Again this is no longer necessary. URBAN PROBLEMS: Following are the main urban problems.
Family or individual-level process that affects and is influenced by the neighborhood spiral:
Four main links between urban structure and crime: 1. Economic effects: · Relative deprivation leading to resentment and anger that is channeled into violence 2. Social disorganization:
CRIME RATES AND URBAN PATTERNS: Rise in socio-economic polarization since 1970s
Inadequate vacancies place a very real and tremendously harmful social burden upon the poor and working poor while lowering the quality of life for all but the cozy upper classes. The burden of inadequate vacancies is most profound on the lower paid working classes, people in difficult transitions and the homeless. 4. HOMELESSNESS—UNHOUSING/UNHOUSED PEOPLE:
5. ENVIRONMENTAL PROBLEMS: Urban environments as systems dependent on:
ENVIRONMENTAL RESULTS FROM:
Cities that allow wood burning in densely overpopulated neighborhoods make life misery for anyone in proximity, especially seniors and people with respiratory problems. ii. WATER SUPPLY: Water’s quality and quantity both are concern. A city of 1 million inhabitants consumes about 1.5 billion gallons of water each day.
As the factories and housing have been in the same areas air, noise and water pollution have been common.Pollution levels along one way streets are often oppressive, toxic and dangerous in many cities. REASONS OF AIR POLLUTION:
Urban infrastructures, in most places, maliciously and willfully designed to oppress the tenant class of humanity through an unofficial system of general inequality. This occurs because the so-called "democratic" process is skewered in favor of people with driveways, who run our governments. Infrastructure problems arises by:
Cities represent places having a high level of accumulation and concentration of economic activities. They are complex spatial structures to be supported by transport systems. The most important transport problems are often related to urban areas, especially when urban transport systems, for a variety of reasons, cannot satisfy the numerous requirements of urban circulation. Urban productivity is highly dependent on the efficiency of its transport system, notably to move labor, consumers and freight between several origins and destinations. The growing complexity of cities has been accompanied by a wide array of urban transportation problems. RESONS OF TRANSPORTATION PROBLEM:
8. EXCESS TRAFFIC: The influx of new residents to inner city neighborhoods brings a dramatic rise in traffic along with aggressive driving and competition for scarce parking. Typical drivers drive faster. It is both a difference in social attitude among newcomers as well as a practical means to switch lanes in crowded traffic. This new level of traffic has brought back increases in pollution such as ozone.
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Success is never achieved by the size of our brain but it is always achieved by the quality of our thoughts.
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#3
Tuesday, January 10, 2012
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Compare the population of southeast asia with the population density of the world
Compare the population of southeast asia with the population density of the world
DENSITY:Density is defined as number of persons living per square kilometer area. The area used for calculating the density is the total area including river and forest area and the population.Population density is made up of two variables. these are number of people and size of the area. Population density =population divided by area Generalizations have stated that population clusters around coasts, rivers, and lowlands. Several sources were checked to determine the average world population density was around 92 people per square mile. COUNTRIES IN SOUTHEAST ASIA: This region contains the Malay Peninsula, Indochina and islands in the Indian Ocean and Pacific Ocean. The countries it contains are:
The total population in the whole world is 6,300,000,000 while thetotal population in southeast asia is 1.2 billion. Southeast asia consititues 25.35% population of the world. China is the most populas country with the population 1,294,629,555 while Indonesia is the 4th most populas country in the world with the population 238,452,952, Philippines is the 12th with population equal to 86,241,697, Vietnam is 13th with population 82,689,518and Thailand is 19th with population 60,424,213, Burma 26th with population 42,720,196, Malaysiais 46th with population 23,522,482,Cambodia 60th with 13,363,421population, Laos ranked 88th with population 5,777,180 Singapore 122nd with 4,353,893population and Brunei Darussalam is 164th with 365,251population. COMPARISON BETWEEN WORLD POPULATION DENSITY AND SOUTHEAST ASIA’S POPULATION DENSITY: The population density of the planet (including all land area) is about 104 people/mi2. If Antarctica is eliminated (since it has zero population density), the world population density rises only to 114 people/mi2. Cities with exceptionally high population densities are often considered to be overpopulated, though the extent to which this is the case depends on factors like quality of housing and infrastructure or access to resources. Most of the largest densely-populated cities are in southern and eastern Asia, though Cairo and Lagos in Africa also fall into the category. The tiny country of Monaco has the world's highest population density. With an area of 3/4 of a square mile and a total population of 32,000, Monaco has a density of almost 43,000 people/mi2. However, since Monaco and other microstates have very high densities due to their extremely small size, Bangladesh is often considered the most densely populated country, with approximately 2,200 people/mi2. Mongolia is the world's least densely populated country with only 4.3 people/mi2. Australia is a close second with 6.4 people/mi2. About 90% of the earth's people live on 10% of the land. Additionally, about 90% of the people live north of the equator. Population density of the entire world is 45 per sq km and that of Southeast Asia region is 222 per sq km. Singapore is 3rd with population density of 6481.5 people/km2, Philippines ranks 42 with the population density of 257.3 people/km2, Vietnam is 46th is 238.6 people/km2, Thailand 76th with 121.6 people/km2, Indonesia 82nd with 108.1 people/km2, Burma 109th with population density equal to 72.4 people/km2, cambodia 111th with 72.4 people/km2, Malaysia is 114th with 68.8 people/km2, Brunei is 122nd with 60.7 people/km2 and Laos 172 with 23.2 people/km2 POPULATION GROWTH RATE: According to population growth rate Laos is 40th in the whole world as its population growth rate is 2.74%, Cambodia is 49th with growth rate equal to 2.49%, Brunei is 53rd with 2.38%, Philippines is 69th with growth rate 2.94%, Malaysia is 67th with 2.08%, Burma is 92 with 1.61% growth rate, Indonesia is 99th with 1.46% growth rate, Veitnam is 104th with 1.37%, Singapore is 116th with 1.15% growth rate and Thailand is 129th in rank according to the growth rate of the world’s countries with growth rate of 0.93%
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Success is never achieved by the size of our brain but it is always achieved by the quality of our thoughts.
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#4
Tuesday, January 10, 2012
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Southeast asia:
SOUTHEAST ASIA:
Between the densely populated countries of china and the Indian subcontinent lies a wide peninsula. It is occupied by people of diverse cultures in the continent courtiers. The countries of this continent are Burma, Thailand Laos, Khmer (Cambodia) and the divided Vietnam. Southwards the broad peninsula gives off to the narrower one of Malaya occupied by west Malaysia and independent Singapore, beyond lies the archipelago of Indonesia, which reaches to south, to the north of which lies the island of Borneo (with east Malaysia, Brunei and Kalimantan) and the Philippine archipelago. The all-embracing title for this area, Southeast Asia came to be used during the Second World War and continues. Southeast Asia provides an interesting example of some of the basic physical factors influencing population distribution. 1. BURMA: Britain conquered Burma over a period of 62 years and incorporated it into its Indian Empire. Burma was administered as a province of India until 1937 when it became a separate, self-governing colony; independence outside of the Commonwealth was attained in 1948 Burma is located in Southeastern Asia, bordering the Andaman Sea and the Bay of Bengal, between Bangladesh and Thailand Her supporters are routinely harassed or jailed its total area is 678,500 sq km. The language of Burma is Burmese. Capital of Burma is Rangoon POPULATION OF BURMA: Burma population is estimated as 42,720,196 in 2004, with the population density being 70 persons per sq km. Roughly three quarters of the population are rural inhabitants, with the remaining population living in urban Yangon, Mandalay and Moulmein. Almost 28% of the population is urban inhabitants. Estimates for this country take into account the effects of excess mortality due to AIDS; this can result in lower population growth rates as in 2003 growth rate was 0.52% while in 2004 it is 0.47% POPULATION DISTRIBUTION ACCORDING TO ETHNIC GROUP AND RELEGION: About two thirds of Myanmar's population is Burman (ethnically close to Tibetans and Chinese) with other minorities making up the other third.68% of the population of Burma is Burman. The Shan make up 9% of the population; The Karen 7%, the Rakhine 4%, Chinese make up 3%, the Mon 2%, Indian 2%, and other 5%. Of the minorities, the Karen and the Shan groups which together make up less than ten percent of Burma’s population are considered to be the two most important ones. With the British occupation, most of the ethnic minorities were kept separate within their borderlands, thus enabling them to maintain their traditions. Since Burman rule, these minorities, especially the Karen with occasional help from Shan political groups and the Kachin have rebelled by using arms. According to religion population is distributed as: 89% are Buddhist, 4% are Christian (Baptist 3%, Roman Catholic 1%), 4% are Muslim, 1% are animist and other 2%. 2. THAILAND: A unified Thai kingdom was established in the mid-14th century. Known as Siam until 1939, Thailand is the only Southeast Asian country never to have been taken over by a European power. It is located in Southeastern Asia, bordering the Andaman Sea and the Gulf of Thailand, southeast of Burma Southeastern Asia, bordering the Andaman Sea and the Gulf of Thailand, southeast of Burma. Its total area is 514,000 sq km. Languages used in Thailand are Thai, English (secondary language of the elite), ethnic and regional dialects. Thailand is divided into 76 provinces. The name of the provinces is same as the capital city. POPULATION IN THAILAND: The population of Thailand according to estimation in 2004 is 64,865,523, about 10 million of whom live in the capital city of Bangkok. Thailand's population is relatively homogeneous. More than 85% speak a dialect of Thai and share a common culture. This core population includes the central Thai (36% of the population), Thai-Lao (32%), northern Thai (8%), and southern Thai (8%). The language of the central Thai population is the language taught in schools and used in government. Several other small Thai-speaking groups include the Shan, Lue, and Phutai. Approximately 68% of the population lives in rural areas and the majority are farmers with incomes reliant upon subsistence agriculture.Rapid change has had a disruptive effect on social structures. Urban migration to Bangkok, the capital city, has led to serious problems Estimates for this country explicitly take into account the effects of excess mortality due to AIDS; this can result in lower population and growth rates. Population growth rate in 2003 was 0.93% and in 2004 it is estimated as 0.91% POPULATION DISTRIBUTION ACCORDING TO ETHNIC GROUP AND RELEGION: Thais form the majority, though the area has historically been a migratory crossroads, and thus strains of Mon, Khmer, Burmese, Lao, Malay, Indian and most strongly, Chinese stock produce a degree of ethnic diversity. Integration is such; however, that culturally and socially there is enormous unity. According to ethnic group population is distributed as: Thai 75%, Chinese 14%, other 11% According to religion population is distributed as: Buddhism 95%, Muslim 3.8%, Christianity 0.5%, Hinduism 0.1%, other 0.6% DENSITY OF POPULATION: Population density can be used as a measurement of any tangible item. However, it is most frequently applied to living organisms. Population density is usually expressed in terms if items or organisms per unit area. Population density of Thailand is 3. VIETNAM: France occupied all of Vietnam by 1884. Independence was declared after World War II, but the French continued to rule until 1954. It is located in Southeastern Asia, bordering the Gulf of Thailand, Gulf of Tonkin, and South China Sea, alongside China, Laos, and Cambodia. Its total area is 329,560 sq km. language used in Vietnam are Vietnamese (official), English (increasingly favored as a second language), some French, Chinese, and Khmer; mountain area languages (Mon-Khmer and Malayo-Polynesian) POPULATION IN VIETNAM: Vietnam is a poor, densely-populated country In Vietnam; the population has increased more than a six-fold during the last century - from around 12 million in 1900 to 82,689,518 today. Population growth rate as estimated in 2004 is 1.3% POPULATION DISTRIBUTION ACCORDING TO ETHNIC GROUP AND RELEGION: Ethnically Vietnam is the most homogenous country of Southeast Asia; about 90 % of the population is Vietnamese. Nevertheless, there are a large number of ethnic minoritiesmaking up the remaining 10% of the population. About 85 % of the 7 millions of Vietnam's ethnic-minority population belong to indigenous ethnic minorities, whose settlement areas have for many centuries been the mountain regions of Vietnam. The largest groups are Thai and Hmong tribes. Contrary to what is the case in Burma and Indonesia, ethnic minorities in Vietnam are not strong enough to seriously aspire their own sovereign states. There are about 1 million ethnic Chinese living in urban centers in the South of the country. Since the Communist takeover the Chinese suffer severe restrictions, reflecting the fact that ethnic Chinese had played a dominant role in the capitalist economic system before the Communist takeover. According to religion, population has been divided into Buddhist, Hoa Hao, Cao Dai, Christian (predominantly Roman Catholic, some Protestant), indigenous beliefs, Muslim 4. MALAYSIA: Malaysia is located in the heart of Southeast Asia, slightly north of the equator. Consisting of 127,000 sq miles (330,200 sq km), Malaysia is divided into two main regions:
POPULATION IN MALAYSIA: The population of Malaysia is multi-racial. Its population according to estimate in 2002 is 22,662,365 million. Population density in Malaysia is 63.7 people every km. The Malays constitutes 57 per cent, Chinese, Indian and other groups constitute the rest of the population. The country itself is geographically halved. The western half, often referred to as the "western peninsula," is the more populated and developed half. The eastern half, often referred to as the "eastern island," is less populated. Its borderingcountries are Brunei and Indonesia.Population growth rate in according to estimate in 2002 is 1.91%. POPULATION DISTRIBUTION: In terms of population distribution by state in Census 2000, Selangor was the most populous state (4.19 million) followed by Johor (2.74 million) and Sabah (2.60 million). Their share of the total population of Malaysia was 18.0%, 11.8% and 10.6% respectively. The least populated states were Wilayah Persekutuan Labuan (0.08 million or 0.3%) and Perlis (0.20 million or 0.9%). POPULATION DISTRIBUTION ACCORDING TO ETHNIC GROUP AND RELEGION: The outstanding characteristic of Malaysia’s population is the highly varied ethnic mix that makes it one of the prime examples of a multi-racial, multi-lingual and multi-religious society in the whole world. The population of Malaysia is currently over 24 million. Malays and other indigenous groups are the predominant ethnic group making up 59% of the population. This is followed by Chinese (32%) and Indian (9%). The official religion in Malaysia is Islam, but other races are free to practice their religions such as Chri. Malaysians of Indian descent comprise about 7% of the population and include Hindus, Muslims, Buddhists and Christians. About 85% of the Indian community is Tamil. 5. SINGAPORE: In contrast to its small size, Singapore has been phenomenal in its successes. A leader in repairing and building ships, Singapore also has a center that refines and distributes oil which is one of the largest in the world. Its harbor is the busiest in the world and is a very popular port for cruise lines. The airport is also the busiest in the world and is also one of the world's best airports with a vast array of amenities available. Singapore, one of the cleanest and safest spots in Asia, draws a crowd of around 6 million visitors each year. A reason for its cleanliness and safety stems from a strict enforcement of rules for even the slightest transgression. Singapore has a varied linguistic, cultural, and religious heritage. English is the national language, but Chinese, Malay and Tamil also are official languages. English is the language of administration and also is widely used in the professions, businesses, and schools. POPULATION IN SINGAPORE: Total population comprises Singapore residents and non-residents. The resident population comprises Singapore citizens and permanent residents. Singapore permanent residents refer to non-citizens who have been granted permanent residence in Singapore. The non-resident population refers to those who are non-citizens and non-permanent residents of Singapore. The population of Singapore has exploded in the last century from a mere 230,000 to an incredible 4 637 500 million in 2004. Singapore has a large foreign population of about 529,870. The top three nationalities come from the Philippines (142,640), Indonesia (85,240) and the USA (32,340). Singapore is one of the most densely populated countries in the world.The population density is 6,004 people per square kilometer. The annual growth rate for 2003 is 0.3%. Singapore generally allows religious freedom, although religious groups are subject to government scrutiny, and some religious sects are restricted or banned. Almost all Malays are Muslim; other Singaporeans are Hindus, Sikhs, Taoists, Buddhists, Confucianists, or Christians. 6. INDONESIA: Indonesia is the world's largest archipelago; it achieved independence from the Netherlands in 1949. It is located in Southeastern Asia, archipelago between the Indian Ocean and the Pacific Ocean. Its total area is 1,919,440 sq km. POPULATION IN INDONESIA: Indonesia's 201 million people make it the world's fourth-most populous nation. The island ofJava is one of the most densely populated areas in the world, with more than 107 million people living in an area the size of New YorkState. Its total population according to estimate in 2004 is 238,452,952. Population growth rate estimated in 2004 is 1.49%. Population density is 109 per sq.km. 41% of the population lives in urban areas. DISTRIBUTION OF POPULATION ACCORDING TO ETHNIC GROUP AND RELIGION: Indonesia includes numerous related but distinct cultural and linguistic groups, many of which are ethnically Malay. According to ethnic group population of Indonesia has been divided as Javanese 45%, Sundanese 14%, Madurese 7.5%, coastal Malays 7.5%, other 26% population has been divided into Muslim 88%, Protestant 5%, Roman Catholic 3%, Hindu 2%, Buddhist 1%, other 1%. Since independence, Bahasa Indonesia (the national language, a form of Malay) has spread throughout the archipelago and has become the language of most written communication, education, government, and business. Many local languages are still important in many areas, however. English is the most widely spoken foreign language. 7. LAOS: In 1975, the Communist Pathet Lao took control of the government, ending a six-century-old monarchy. Initial closer ties to Vietnam and socialization were replaced with a gradual return to private enterprise, a liberalization of foreign investment laws, and the admission into ASEAN in 1997. It is located in Southeastern Asia, northeast of Thailand, west of Vietnam. Its total area is 236,800 sq km. there are 18 provinces in Laos. POPULATION IN LAOS: According to estimate in 2004 its total population is 6,068,117 which in terms of population makes Laos the third smallest country in Southeast Asia (after Brunei with 300,000 and Singapore with 3.1 Million). Population growth rate in 2004 is 2.44%. Population density of Laos is 23 per sq.km. 23% of the total population lives in urban areas. DISTRIBUTION OF POPULATION: About half of the country's population is Laotians, a people ethnically closely related to the Thais. The languages Thai and Laotian are also very similar. Lao Loum (lowland) 68%, Lao Theung (upland) 22%, Lao Soung (highland) including the Hmong and the Yao 9% Roughly one quarter of the population, mostly to the South, ethnically belongs, like the Cambodians, to the Mon-Khmer group, about 15 % are Thais, and various hill tribes make up another 10 % of the population. Laos is one of the very few countries in Southeast Asia without significant ethnic tensions. The long-time leader of the communist movement in Laos, former Prime Minister Kaysone Phomvihan, was born of a Vietnamese and a Laotian parent. In Laos there are religions like Buddhist 60% of the population, animist and other 40% of the population (including various Christian denominations 1.5%) The citizens of the country have a reputation for being extremely peaceful and friendly - even though Laos had been caught up in the Vietnam War and in a civil war lasting for years. 8. KHMER (COMBODIA): Cambodia stretches along the southern reaches of the Mekong River in south west Indochina, covering a total area of 181.040 km2. It is bordered by Thailand, Laos, and Vietnam. The national language is Khmer. It is related to ancient Indian languages. POPULATION IN KHMER: Cambodia has a population of 13,363,421million according to estimate in 2004. An estimated 85-90 percent of the population lives in rural areas. The average life-expectancy is 58.41. For every 1,000 newborn children, 73.67 will die before they are a year old. Only 69.9% of the population can read and write. Eestimates for this country take into account the effects of excess mortality due to AIDS; this can result in lower population growth rates than would otherwise be expected Population growth rate is 1.8% in 2004. Population density varies throughout Cambodia. The average population density of 50 persons per km2 The Cambodian population presents several important features. First, due to the baby' boom after 1979, it is a young population with at least half (50% according to some sources, more according to others) under 18 years of age now. Secondly, the proportion of women in the adult population is high, 56% of those who are 18 years old or more being females. Also as a result of the war, there is a rather high proportion of women-headed household; at least 25% according to UNICEF. Cambodia and Laos' populations are dwarfed by those of Vietnam and Thailand, and average population densities in the smaller countries are much lower than in Vietnam. Even the very densely populated areas in Cambodia do not have such a concentration of population as can be found in the Red River and Mekong River Deltas in Vietnam. POPULATION DISTRIBUTION IN KHMER: 90% of the population is Khmer. The rest are 5% Vietnamese, 1%Chinese, or Cham and 4% others. There are about 7 people groups in Cambodia. Ethnic Khmer were concentrated in central and in southeastern Cambodia. The Cham lived in their own towns and sections in larger cities. The Chinese lived mainly in urban centers; in Phnom Penh they were concentrated around the markets. The Vietnamese tended to live in their own villages and in certain sections of Phnom Penh. The Khmer Loeu was concentrated in the northeastern and southwestern areas of Cambodia. In Cambodia 95% of the total population are Theravada Buddhist while others are 5% 9. PHILIPPINES: The Philippines were ceded by Spain to the US in 1898 following the Spanish-American War. They attained independence in 1946 after Japanese occupation in World War II. It is located in Southeastern Asia, archipelago between the Philippine Sea and the South China Sea, east of Vietnam and its total area is 300,000 sq km POPULATION OF PHILIPPINES: Its total population as estimated in 2004 is 86,241,697. Population growth rate is 1.88%. Density of population is 255 per sq.km. 59% of the total population lives in urban areas. The average life-expectancy is 69.6 years. For every 1,000 newborn children, 24.24 will die before they are a year old. Only 95.9%of the population can read and write. POPULATION DISTRIBUTION IN PHILIPPINES: About 91.5% of the population is Christian Malay, 4% are Muslim Malay, and 1.5% is Chinese and other 3% of the total population. Roman Catholic are 83% of population, Protestant 9%, Muslim 5%, Buddhist and other 3%. In Philippines there are two official languages - Filipino and English and eight major dialects
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Success is never achieved by the size of our brain but it is always achieved by the quality of our thoughts.
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Tuesday, January 10, 2012
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Types of Farming
INTRODUCTION
Farming is the cultivation of food crops, livestock, poultry and inedible crops such as cotton, tobacco and flax. We can say that the farming is the process of producing food and fiber from the land. Farming is one of the man’s oldest occupations. Man probably first began to raise crops and animals about 10,000 years ago. Today, farming is the largest and most important of all occupations. It is estimated that three out of every four persons throughout the world live on farms. Presently, there are about 3 million farms in the US, of which 95% sell more than $2,500 worth of farm products annually. In many regions of the world, farmers still use primitive tools and methods, some of which have not changed since the stone ages e.g., hand rack and bull cart etc. In more technologically advanced areas new scientific tools and techniques are constantly being developed. IMPORTANCE Farming is of critical importance as the major source of food for people in all nations. More than 90% of the total world supply of food comes from farms including ranches; the rest comes from fishing and hunting. REQUIREMENTS FOR THE DEVELOPMENT OF FARMING Because the world population is growing still at near the fastest rate in history and the aggregate net population growth is increasing year by year, there is critical need for development of farming and for efficient use of the resources devoted to agricultural or farming use. It may be assumed that the food problems of the world are manageable if appropriate attention is given to development of farming and to the services required for the marketing and for supply of inputs to farms and if rates of population-increase are eventually brought under control. Sustained growth of farming requires that improved technology be developed for all major phases or factors of production. This includes development and adaptation of new varieties of crops, improvements in fertilizer production and distribution, appropriate use of chemicals for plant and animal protection, more efficient water management and improved methods of plant and animal culture. The development of farming as a central means of solving the world’s hunger, malnutrition and poverty problems is one of the most critical needs of this generation. TYPES OF FARMING SHIFTING CULTIVATION OR PRIMITIVE SUBSISTENCE FARMING Introduction Shifting Cultivation is one of the most primitive (ancient) types of agriculture or farming practised in Southeast Asia, Central Africa and tropical America. Shifting cultivation is the first endeavor of people to control static resources, i.e., the bounty of the land. It manifests only rudimentary (basic) technical management of the land, and limited amount of time, effort and capital are devoted to this activity. Unlike other economic activities, shifting cultivation is still practised widely in the modern world. Characteristics Its chief characteristic is that the new land is cleared usually from forest, cultivated for one to three years and then abandon. A new plot of land is then cleared and again abandoned after a few years. It is in this way that the shifting cultivation goes on from forest to forest and plot to plot. The selection of land is done by experienced persons, since every land is not suited for shifting cultivation. A virgin forest with less or little undergrowth is the first choice. In an untouched forestland, fertility is ensured and little undergrowth makes the clearance of forest an easy job. Clearing starts after the rainy season. Tall trees are felled and then burnt down with other trees and bushes. Burning results in an accumulation of ashes, which add potash to the soil. Clearing is done by a group of persons or a tribe. Cleared land is then divided among various families, which start sowing. Usually they dig holes and put into them the seeds of various crops, which are mixed together. Occasionally, ridges are made on which seeds are sown. This is done immediately before rains, so that the seeds may germinate with the first rain. Various crops become ready for harvesting at different periods and are harvested accordingly. Rice in Asia, millet in Africa, and maize in America are the important crops. Other crops are beans, peas, cucumbers, tomatoes, yams, cotton etc. Some root crops are also grown. The crops have to be protected against birds, rats, ants and other small animals. Implements that they use are very crude and include digging sticks, spades, hoes, picks etc. All the work is done by human muscles. No farm animals are used. Chickens, ducks and fowls are kept. After a few years, ranging from 1 to 3, the land gets exhausted. The soils are washed away and the plot has to be abandoned. The fields so abandoned are cultivated again, after 4 to 5 years or even after longer periods. Regions Today there are three broad regions where shifting cultivation can be found. The largest and most populous is in Central Africa. Straddling (having ½ on each side) the equator, nearly half of the continent lies in this zone. The second major region lies in Southeast Asia and the adjacent offshore islands, from Sumatra eastward through Borneo, Papua New Guinea, the New Hebrides (now called Vanuatu), and numerous tropical islands of the Pacific Ocean. On the mainland of Asia, shifting cultivation tends to be confined to the interior of Burma, Thailand, Cambodia and adjacent portions of India and China. The third region where shifting cultivation is practised embraces most of the Amazon Basin, reaching from the Atlantic Coast to the Andes Mountains and from Bolivia to Venezuela. The practice of shifting agriculture is also found in Ecuador and Columbia and extends northwards through Central America into Southern Mexico. A small part of the West Indies is also included. It is generally recognized here as well as in other major regions, that shifting cultivation is the prevailing activity, but it co-exists with other forms of economic livelihood. Manpower Engaged Recent estimates by the Food and Agricultural Organization (FAO) indicate that nearly 200 million people make their living by this system of agriculture. The FAO also reports that shifting cultivators occupy 33 million km2 of land, which is nearly twice the total area of the world’s permanent cropland. This statistic illustrates the low population densities of these areas and the extensive character of the economic activities. Of the 200 million shifting cultivators, it is estimated that perhaps 75% live in Africa, with most of the remainder in Asia. The region possessing the fewest shifting cultivators is Latin America. Defects It is a very primitive, crude and exhaustive type of farming. It encourages erosion and destroys forest wealth. Such a system of agriculture makes poor use of land, and it yields only a very simple livelihood. The areas of primitive subsistence farming are probably the most backward in the world, but they are also among the most thinly populated, so the number of people who live by this form of agriculture is very small; perhaps less than 1% of the world’s population. Shifting cultivators have long known that the fire is a simple method of clearing land of wild vegetation. Unfortunately they also believe that ashes provide a good fertilizer for the soils. Ash helps a little, but because the organic matter in the soil is combustible, the fire also acts to partially destroy its fertility. Others Names This type of agriculture is known as Thuming in Bangladesh, Taungya in Burma, Ladang in Indonesia, Zande in Africa and Milpo in Americas. SUBSISTENCE FARMING Introduction This type of farming indicates the poor means of the farmer or uneconomic holding at his disposal. It is also known as the Domestic Farming, because such farming was originally carried on to meet the domestic requirements of the farmers. But gradually this concept has changed. Now the surplus produced is sold in the home and foreign market also. This type of farming is mostly practised in monsoon land of Asia. Characteristics A striking feature of farming in monsoon lands is the tillage (cultivation) of small holdings, which is one of the chief causes of rural poverty. Dense population mostly comprising of agriculturists; small capital resources, high percentage of tenancy (leasing), high rate of interest, and high rents make it practically impossible for the individual farmers to secure more land area. Most farm labor is family itself, which averages from 4 to 7 persons. No outside labor is employed. Further, these small farms are sub-divided into small patches of land separated only by low ridges or dikes on the top of which are footpaths. Implements and Products Quite old and simple implements are used. Animals like oxen or horses are used for drawing plough. Scarce resources do not permit the costly use of machinery or other labor saving devices. The farmer has mostly to depend on weather condition and also cannot improve soil by using latest fertilizers. Rice, wheat, millet, maize, beans, pulses, fruit, barley, oil seeds, sweet potatoes and vegetables are commonly grown in subsistence farming. Rice is the most important product of this type of farming in monsoon lands. In some areas sugarcane and cotton are also produced. Supplementary Activities Just to supplement the income, poultry farms and dairy cattle industries are also found as the agricultural activities. This side activity is not unknown in Pakistan and India. In the villages, cows, goats, hens, ducks, and buffaloes are seen almost in every house. In China and Japan, importance for farm animals is not felt yet. Horses, sheep and goats are found but in negligible number. Besides the above said activities, the farmers also scour wool, spin yarn, tan leather, weave cloth and also undertake tailoring and carpenting works. They work in the field during farming season and the rest of the time is utilized for carrying a number of other works to supplement their income and to meet the local requirements. INTENSIVE FARMING Definition Farming in which a comparatively large amount of labor and working capital is used per tillable acre of farmland is called Intensive Farming. It is a system of farming aimed at raising yield per unit area. Areas Intensive farming is common in areas where land is scarce, such as in Asia, and where land is expensive or the crop is costly to produce, such as on the irrigated track farms of California. The farmer uses almost every foot of land and attempts to produce as large a crop as possible on the available land. In Europe, farming must be intensive, for most farms are small and many people live in a small area. Characteristics 1. Intensive farms tend to be relatively small and very efficient. 2. An intensive farmer tries to get a large crop from small piece of land. He spends much labor and material on it. 3. Farming often has to be intensive where the land is scarce. 4. When a farmer devotes a great deal of labor to a piece of land, he is practicing intensive farming. 5. Intensive agriculture usually goes together with small farms. 6. A great deal of careful work is always involved in intensive farming. Often this work must be done by hand. 7. In some cases more than one crop a year is grown on the same land. 8. Intensive farming demands a great deal of labor and high expenses for each acre of land. 9. The yield per acre is also usually high. The farmer hopes to get a high return, but it depends on the market for his crop. 10. Intensive agriculture can also be practised on a large scale, as on large fruit or vegetable farms. 11. Vegetables, small fruits and other crops that have a comparatively short growing season are produced by intensive farming. 12. Intensive farming is specially successful in dairy farming, fruit growing, truck farming, and for irrigated land. Examples 1. Commercial egg production, where thousands of hens may be kept in buildings on a lot, the size of a city block, is an example of intensive farming. 2. The old time southern plantations were examples of large scale intensive agriculture. 3. The raising of apples is a good example of intensive farming or fruit growing, the grower aims to raise the largest possible amount of fruit that can be sold. To do this he must give careful attention to the orchard and make wise use of cover crops. For a good crop, he must not overlook pruning, spraying and cultivation. These suggestions are just as good for raising peaches, pears, plums, grapes and small fruits such as strawberries. 4. All truck farming has to be intensive. Success depends on fertile soil, constant and thorough cultivation, and wise use of fertilizer. Crops like onions, tomatoes, lettuce, cabbage, and cauliflower occasionally bring a profit of several thousand rupees an acre when they are cared-for properly and prices are favorable. 5. All land under irrigation is farmed intensively. Water for irrigation means an additional cost, so the farmer must grow highly profitable crops. EXTENSIVE FARMING Definition Farming in which a relatively small amount of labor is spread over a large tract of land is called Extensive Farming. This type of farming is based on the use of a big area of land with minimum upkeep and expenses. Areas Extensive farming is characteristic of large wheat farms in the Great Plains area and in other parts of the world where rainfall is likely to be a limiting factor. Characteristic Features Extensive farming consists of cultivating large tracts of land, but often the yields per acre are lower than those of intensive farming. An extensive farmer spreads the same amount of labor and materials, as an intensive farmer, but he grows less per acre than the intensive farmer does. Farmer can be extensive only where land is plentiful. When a farmer works on a large area of land with relatively little labor, he is practicing extensive farming. Extensive agriculture is usually practised on large farms or ranches where most of the work is done by machinery. There is work at planting time and harvesting time. Otherwise the crops need little attention. Extensive farming does not yield as great a return per acre of land as intensive farming, but it requires much less work per acre. Examples The large farms that raise wheat and other grain crops in the mid-western United States, and Canada’s Prairie provinces are good examples of Extensive farming. Raising cattle on the range is another example of extensive farming. Mixed farming practised in east central USA is an example of extensive farming. Of all economic endeavors, gathering requires the least amount of capital investment and effort, but considerable space is required. It is an example of extensive farming, requiring a large quantity of land to support each person. Gathering persists primarily in isolated pockets in the low latitudes, including the territories of some Indian tribes dispersed throughout Amazon Basin (Brazil, Peru, Ecuador and Venezuela), together with a few stretches within tropical Africa, the northern fringe of Australia, the interior of New Guinea, and the interior portion of southeast Asia (Burma, Thailand and China). Difference between Intensive and Extensive Farming The difference between intensive and extensive farming refers to the degree to which land and labor are utilized to produce food. Extensive farming uses a lot of land in relation to the product yields, whereas intensive farming yields considerable output through greater labor and technology investment. (also see Notes) INTENSIVE SUBSISTENCE FARMING Introduction Intensive subsistence farming is mostly practised in the monsoon lands of Asia. It is a very intensive type of farming. The classic farms of intensive subsistence agriculture, found today in Pakistan, China, India, southeast Asia, Korea and Japan involve high levels of output per unit of land. This intensive use of land produces relatively large yields per acre, but frequently little surplus occur because of the vast food needs of the tremendous domestic population that is supported by this agricultural system. In Japan, however, considerable surpluses do exist, owing to the impact of modern practices, including the use of hybrid seeds, mechanization, modern irrigation practices and commercial fertilizers. Implements and Crops A family comprising 5 to 7 members has on an average 2 acres of land, which is also not in a single plot but is dispersed over a large area in small plots. So the use of modern farm machinery is difficult. A wooden plough drawn by a pair of oxen is the most important agricultural implement to which spades, sickles and hoes may be added to complete the picture. Most of the work from preparation of field to harvesting and the sowing of crops are done by manual labor. Rice is the most distinctive crop of the rainier parts and wheat of the drier parts. Millets, maize, gram, pulses, oil seeds, barley, sweet potatoes, vegetables and fruits are other crops. Farm Animals Animals do not form an inseparable part of the farm unlike north western Europe. Cattle are kept by many farmers in India and Pakistan. In China and Japan, farm animals, all the more, go in background. Horses, sheep and goats are found in negligible number. Cropping Techniques Cropping methods and the types of crops grown, distinguish intensive subsistence farming from other types. Rice is typically the principal crop. The highest yields occur with wet rice, which is grown in paddy fields. These fields are typically small dug-out areas that lie about 3 inches below the ground level, bounded by narrow dikes, dams or roadways. The recessed fields permit flooding during the grown season. Another type of paddy is created by dammed-up terraces, which can also be irrigated. Upland rice grown in non-irrigated areas provides far lower yields. This form is called dry rice. The Asian rice field typically occupies the space of a garden plot, being an acre or less in size. Elaborate irrigation, circulation and drainage systems sustain the high yields. Flood plains are favored locations because of their proximity to water and the ease of setting up hydraulic systems on relatively flat land. In recent years, the number of drilled wells and electric pumps used to supplement surface water from reservoirs and rivers in rice growing areas has grown dramatically. Rice agriculture requires a warm growing season (average temperature 70 oF), 4 to 6 months in length. Water requirements are also high. When temperatures are cooler and growing season shorter, wheat is often substituted for rice as the second crop. In areas unfit for rice cultivation, two crops of wheat may be grown. Other grains, such as barley, millet, and sorghum are also produced as food crops. Many farmers augment (increase) their cereal grain crops with corns, beans, peas, melons and fruits to supplement their diets. Often a practice called inter-culture permits the simultaneous growing of a second crop between the rows of the main crop or on dikes between paddy fields. Industrial cash crops are also grown including cotton, tea, sugarcane, rapeseed and jute. MIXED FARMING Introduction This type of farming indicates two main activities of the agriculturists. One is Cultivation and the other is Cattle Breeding. It may be both intensive as in Western Europe or extensive as in East Central USA. This farming is practised specially in those parts of the world where land is not mostly fertile. The holding or size of the farms is not big enough and due to low fertility of soil many crops cannot be grown in one year. Hence when one crop is harvested, the farms are left uncultivated for recouping fertility. Thus the farmers get a compelled vacation which is called their off-season. It is during this season that they like to pay more attention on rearing animals, poultry or take-up some handicrafts, i.e., cottage industries. Mixed farming can take many forms and it may be practised on farms, which range in size from a few hectares (2.471 acres) to hundreds. But crop growing and animal rearing are intimately related, whatever the conditions, and all the cropping systems yield both human and animal food. The latter is fed to animals, which in turn yield manure for the land. Areas This system of farming predominates in regions with a dense and highly urbanized population. Mixed farming encompasses much of the eastern US, western Europe, and large portions of the fertile triangle in the Soviet Union, northwestern USA, central Mexico, southern Brazil, parts of Pampas (Argentina), central Chile, and South Africa are other parts of mixed farming. From western Europe, a belt of mixed farming extends eastward into the Asiatic Russia through the central part of the European Russia. Crops and animals occur in various combinations throughout these regions, but the role of crops is particularly crucial in that they provide multiple roles as feed for animals, as a cash crop and as a food supply for farm families. Crops Apart from cereals like corn in the USA and wheat in western Europe, oats, rye, hay and root crops are grown. In urban areas fruit gardening and dairy farming are very common. Cropping Techniques There is usually a regular system of crop rotation, including bread grains (wheat or rye), fodder grains (oats and barley), roots such as potatoes and turnips, and legumes, and fodder crops like lucerne and alfalfa. Some of the land is commonly under permanent or rotation grass. Beef cattle or sheep are sometimes kept in conjunction with crop farming, though it is more usual for dairy cattle and pigs to be reared. Equipment In some areas – in Poland and in parts of France, for example – farms are often small – 10 hectares or less – and make very little use of expensive equipment and the peasants sell very little of what they produce. In other places, such as parts of England, farms are highly capitalized, i.e., they are large and make the greatest possible use of machines and the majority of the crops and animal products are sent to the market. Animals 2/3rd of the animals kept are meat giving of which cattle and hogs are most important. Oxen and horses are also kept as draft animals. Mixed Farming in Indo-Pak Sub-Continent We find mixed farming on the hilly regions in Indo-Pak sub-continent where raising of only one crop is possible during rainy season. In rest of the year’s time, the farmers prefer to raise their goats, sheep, cows, poultry etc. Besides they also remain busy in making baskets, shoes, other leather goods, mats, earthen or wooden wares or toys and such other goods which are easily marketable. This gives them some cash income with which they make purchases of seeds, clothes and other requirements. When surplus grain is grown, it is sold in nearby markets. Similarly, the animals and poultry are also sold in markets. Advantage It is a flexible form of agriculture, well-suited to a wide range of physical conditions, and can be adapted to changing market conditions fairly quickly. Production of milk, bacon or bread crops can be increased or reduced at short notice according to the demand. This suggests that it is well-suited to provide many of the animal and vegetable products required by those who live and work in the towns. Mixed farming makes maximum use of the soil in mid latitude regions of damp climate; the rotation of crops, the periodic grassing over arable lands, and the use of Farm Yard Manure (FYM), all help to maintain the quality of the soil. COMMERCIAL GRAIN FARMING Introduction This is a form of farming which concentrates on the production of a single crop, namely wheat, maize or barley. It is found outside the tropics, and even there only where the rainfall is too low (less than about 500 mm) for mixed or dairy farming. Commercial grain farming is most often associated with the wheat belts of the world. Commercial grain farmers typically specialize in producing a single crop – wheat – but often rotate production with other grains or forage crops. The proportion of farmland devoted to cash cropping attains unusually higher percentages in commercial grain regions. Areas Commercial grain farming is the characteristic of the temperate grasslands or savanna. The most important areas of commercial grain – chiefly wheat – production are parts of the mid west of the US and the Canadian prairies (broad grassy rolling tract of land), the Pampas of Argentina, the Steppes of southern Russia, the southeast Europe and Siberia, and the grasslands of the southeastern Australia. They are located in the semi-arid belt where the rainfall is precarious, population is low, and a century back was occupied by the nomadic herders. Physical Factors Commercial grain farming competes best in the areas with atleast 12 to 20 inches of rainfall, preferably occurring even during the winter, spring and early summer months. Wheat can tolerate hot, dry summers and infact prefers a less humid growing season then does corn. Temperature and precipitation factors in combination help to explain the distinctive locations of winter and spring wheat growing areas. Both types prefer a cool, moist season initially, followed by a warm, sunny, dry period during maturation. Machinery Extensive flat plans are available so that the farm machinery like tractors and combines can be profitably used. The low population has been a great incentive to the mechanization of agriculture. Farms are very large ranging from 350 to 2,000 acres. As a general rule, they are highly mechanized and use every form of labor saving equipment. They use very little labor. Crops and Yield Wheat is the distinctive crop of the region, like that of rice of the monsoon lands of Asia. The yield per acre is not so high as that of the western Europe but yield per head is very high so that large quantities enter the world market. Transportation and storage facilities have been provided for the marketing of wheat and other cereals like rye, oats, barley etc. Economy of the temperate grasslands is primarily based upon grains though a little amount of flax, hay, vegetables and fruits are also grown. Advantages and Disadvantages Most of the world’s commercial grain is produced in these regions. Wheat is often the only crop grown although it may alternate with a fodder crop, such as oats or sorghum, which is adapted to the fairly dry conditions. The increasing world shortage has led to the extension of grain growing lands which are too dry, and better left for grazing. In such a climate the rainfall is highly unreliable. Years in which it is adequate for wheat may be followed by a span of years when it is quite inadequate, and crops wither (decay). A further danger is the blowing of the top soil in such dry climates whenever grass cover is ploughed. In the US, such dry lands were ploughed and sown in the 1920s, with disastrous results. Dust Bowl in the USA in 1930 is a good example of it when top soil of a vast land was blown away. PLANTATION FARMING Introduction It is a sister of commercial grain farming and differs from it because that has only grain production. Plantation is a type of commercial farming practiced in the tropical lands of southeast Asia, Africa, Central and South America. Farms are unusually large, in which commonly one cash crop is grown. No form of commercial agriculture is as heavily dependent on market conditions as plantation farming. The plantation is essentially a farm, run on up-to-date lines and making use of the most recent scientific knowledge, which produces a single crop all for sale. Plantation is one of the oldest systems of commercial agriculture. At the same time, it occupies less space today than any other form of commercial cropping. Locations The world’s plantations are located along tropical coasts, inland near navigable rivers, or along railroads extending into the interiors. These locations help in the relatively efficient and inexpensive transportation of products to be exported from factory to port. Geographical location and environmental factors also help contribute to the fact that plantation often specialize in a single crop. This is known as Monoculture, and it is a critical and distinctive feature of what was the old plantation system. Crops The earliest plantations were the sugar states of West Indies and Brazil, then the practice was adopted of growing rubber, tea, cacao, palm oil, coffee and abaca (sisal hemp) on plantation basis. All these crops grow best in the equatorial or tropical regions. The products of plantation farms are invariably cash crops which are generally consumed in north western Europe and USA. Hence the farms must be served with best transportation facilities. Size of Land Although plantation states around the world incorporate relatively large holdings, they vary considerably in size. In Sri Lanka for example, an state must contain at least 10 acres to qualify legally as a plantation. In Sarawak, Malaysia, the figure is 1,000 acres. Many of the rubber plantations in Malaysia comprise only about 100 acres. At the other extreme, the Fire Stone Company Rubber Plantation at Harbel, Liberia includes almost 136,000 acres. Machinery Traditionally commercial plantations occupy relatively large units of land, usually found in sparsely populated areas of the tropics. They employ large numbers of imported, unskilled and low paid laborers who, through careful supervision, concentrate on producing one or more crops for export. Although the crops are produced mainly by intensive hand labor, they must be harvested in a careful and organized way, and they have to be processed in some manner before leaving the state. Factories are therefore common entities on the plantation landscape. Labor An army of cheap labor is required. They are generally not available locally and hence have to be imported from outside. In southeast Asia, Indian and Chinese laborers are employed in large number for whom quarters have to built, medical aid has to be provided, and amenities of life have to be arranged. Conveyance charges from home to the plantation and back have to be borne. It has been estimated that cost of labor equals to more than half of the total cost of the production. Capital and Skill Plantation farming requires investment of huge capital and great organizational skill. The capital and organizational skill come from Europe and the USA. Thus, it will evident that in plantation farming, except the cheap lands of humid tropical region, all other things come from outside – labor, organizational staff and capital – and the products are exported to other countries. Historical Antecedents Plantations have existed for over 500 years. They were created in response to a demand in Europe for food, spices, fibers and beverages that because of climatic constraints, could be produced only in the tropics or sub-tropics. Over the centuries, the demand for most of these items has increased with the growth of world population and with the insatiable (unfulfilled) needs of modern western society. During that time, North America, specially the US, has equated or even surpassed Europe as a market for tropical agricultural products. The plantation system is considerably older in tropical America than in Asia, Oceania and Africa. Actually, the first plantations date to the 15th century establishments located on several islands off the Guinea Coast of Africa. From there, the Portuguese introduced the system to northeast Brazil to produce sugarcane. When plantations were introduced into the sub-tropics of North America into the 17th century; indigo, tobacco and cotton were the major cash crops. Commercial crops from Asia and Africa came to Europe in the 19th century, but they were grown primarily by indigenous peasant farmers. Commercial agricultural development of the Asian tropics did not begin in earnest until the Suez Canal was opened in 1869. This together with steam replacing sails, made Asia closer to Europe in travel time. The increase in Asian produce also coincided with a new mass demand in Europe, owing to the effects of the industrial revolution. This demand was particularly acute for certain products grown in Asia, specially rubber and vegetable oils. Africa was the last region of the tropics to experience plantation development. The plantation system never caught-on in Africa. Infact, only in the German colonies of Cameroon and Togo, where the economies totally dominated by plantations. The situation in post colonial Africa in the late 20th century is essentially the same. In only a few African countries today will one find a thriving plantation economy. The history of plantation can thus be divided into three distinct phases: 1. The old plantation system flourished in Americas before the 19th century. 2. The new plantation system developed in Asia in 19th century to meet the demands of a modern industrial society in Europe, one that required raw goods for the factory just as much as food for consumption. 3. The third phase of plantation development is underway presently, and future attempts by third world nations to gain control over the production and marketing of the agricultural goods grown on their land. Recent Changes Plantation has evolved consistently over the past centuries, but in the last 30 years or so, they have changed in surprising way. The usual classification of plantation farming as strictly as tropical institution can no longer hold in light of developments elsewhere. Those characteristics considered essential to the plantation – crop specialization, advanced cultivation and harvesting techniques, large operating units, centralized management, labor specialization, massive production and heavy capital investment – have become increasingly associated with farm in the middle latitudes. By the same token, the character of the tropical plantation has begun to change. Monoculture has declined in some locales, and crops usually associated with cooler climates have been modified and are being cultivated in the tropics. While the plantation economy was originally geared exclusively to exporting goods to foreign markets, domestic markets in the tropics have recently increased in importance. Third world governments commonly promote them as an important element of their overall rural development strategies. Most plantations were established by Europeans in colonial territories, which they controlled. Now that these territories gained their independence, they no longer look on foreign-owned plantation with favor. Notwithstanding these important modern developments, the plantation is undeniably the product of the colonial past. In much of the third world, it remains as a symbol of oppression, economic exploitation, and cultural domination by Europeans. TRUCK FARMING Introduction Vegetables growing on commercial basis is known as truck farming or market gardening. On account of its perishable character, it is usually carried-on in the outskirts of big towns and cities or industrial centers which offer a ready market. The improved means of rapid communication is making possible the growing of vegetables at places quite remote from the urban centers. Thus in USA, the vegetables grown in Florida are marketed in New York and other adjoining industrial centers. Truck farming is often done in poor lands. The deficiency in soils is made good by the use of heavy fertilizers. Location The single largest truck farming region in the world is located on the Atlantic coast of USA. The area is covered with poor sandy soils and is not suited to the production of cereals and cotton. Heavy application of fertilizers has turned it into a huge vegetable garden. Trucks, fast moving trains, and aeroplanes are employed in transporting the perishable vegetables from the farm to the market. Modifications The prices that the vegetables fetch, and the restricted distance at which the markets must be located have made possible the growing of vegetables in areas of adverse climate. In California where killing frost is a constant danger, artificial heaters are used and in northwestern Europe vegetables are produced in greenhouses. Necessary requirements for Truck Farming Because of the perishable nature of the products, the truck farming can be practised efficiently and economically only under the following conditions: 4. It must be near the big commercial and industrial centers which will provide big and ready markets for its products. 5. Modern methods of transport are available at a cheap rate for the quick movement of the goods all the year round. 6. Air conditioned compartments in the train for perishable goods are necessary. 7. Cold storage is also necessary for storing perishable products. HERDING Introduction Herding is a more advanced economic activity than either Gathering or Hunting since those who live by it make at atleast some investment to enhance natural production. Herding activity encompasses the single largest territory on earth. The semi-arid grasslands of Central Asia, Southwestern Asia, and North Africa are the principal areas of herding. Life in such areas is nomadic or semi-nomadic. Search for feed and water for the live-stock demands constant movement. Herds are kept chiefly on natural vegetation. Several acres are required to feed one animal. Hence an extensive use of land is made. The number of cattle in these areas is not large. Cattle is raised primarily for milk, and beef if of minor importance. Sometimes cattle are kept simply for the sake of prestige. The nomadic herding areas have subsistence economy. Therefore very little of their products enter world market. Areas In the late 20th century, one vast area of herding can be demarcated. It extends all the way from the Atlantic shores of North Africa eastward across Africa through the Arabian Peninsula, then deep into inner Asia, almost to the Pacific Ocean – a longitudinal extent of over 8,000 miles. Latitudinally, this arid and semi-arid region extends from 5o South latitude on the east coast of Africa to 50o north latitude in Central Asia – a range of over 3,500 miles. These pastorals occupy some 10 million miles2, twice the area of land devoted to cultivation. A lesser region of herding is found in Northern Eurasia, extending into Alaska. In the southern hemisphere too, there are small areas in southwest Africa and on the island of Madagascar. Herding is absent from Australia, South America, and most of North America. Manpower Engaged It is estimated that there are 3.5 million herders in the Sahara, Sahel and Sudan zones of Africa, over half a million in the Middle East and the Indus River Plains of Asia, in the ex-Soviet Union, and in China. This makes for a total of approximately 15 million pastorals (rural). Animals The animals that have proved most satisfactory are sheep, goat, cattle, camel, reindeer and yaks. Horses are used in some areas, but they usually perform the special function of transporting the herdsman as they tend their animals. Goats, which can endure considerable aridity, constitute the herds in the driest regions, whereas sheep and camel predominate in places with somewhat heavier rainfall. The wetter fringes of the dry lands can support herds of cattle. Material Culture of Herders The material culture of herders is characterized specifically by a dependence on domestic animals. The economic needs of herders are met by animals that feed on wild plains rather than on cultivated crops. Animals supply food (milk, cheese and meat), materials for clothing (fibers and skins), shelter (skins), fuel (excrement), and tools (bones). Meat plays a small role in the diet of the true nomadic herder, because animals are rarely killed except on special ceremonial occasions. Migration and the mobility that are required for successful herding are basic features of the life of these people. Movement in search of pastures can be undertaken either over vast horizontal distances or vertically from one elevation to another. The latter practice is known as Transhumance and can be found in such places as the Andes, Himalayas and East Africa. Transhumance is also practiced by modern animals herders in the Alps, Pyrenees (southwestern Europe/Spain), Caucasus and Rocky Mountains. From Morocco to North China, the search for water and pastures is the critical fact of life. Physical Environments of Herding Areas Most of the regions where herding occurs possess an arid or semi-arid climate – usually less than 20 inches of precipitation is recorded. Under these physical circumstances, trees do not grow over broad areas; as grasses and shrubs comprise the natural vegetation. Wherever an adequate supply of moisture is found, however, some form of agriculture is normally is practiced. Movements The unending movements of herdsmen and their animals is both horizontal and vertical. They must move because supplies at any given time in any given place are limited and because the rains come at different time in different places. Because high lands tend to wetter than lowlands, herdsmen practice transhumance by moving to higher altitudes to find grass for their animals. There are, of course, seasonal variations in forest supplies at different elevations, but the factor that determines when they go up or come down is temperature not precipitation. Pastorals tend to lowlands in the winter and move to upland pastures during summer. As autumn approaches and frost begins to occur, herds are returned to the lower lands. LIVESTOCK RANCHING Introduction Livestock ranching typically finds its home most distant from the market, being an extensive form of commercial agriculture. Commercial ranching resembles tropical plantation farming in that it also uses a large area land to produce a single commodity, fat-stock, i.e., sheep and cattle, which are primarily reared for their meat. A very large area of the earth’s surface is made up of dry grasslands, which yields a course grazing, usually for cattle or sheep. The animals are reared in almost wild conditions on the ranches, and are rounded up at intervals. Livestock Production Regions On a world scale, just five regions have the majority of livestock ranching. In North America, a broad region, extends from western Canada southward through the western US to central Mexico. In South America, the major livestock ranching area extends from the southern tip of Argentina northward through Brazil encompassing virtually all of the southeastern third of the continent. Venezuela also has a small producing area at the northern end of the continent. The third major producing area lies in Southern Africa and a forth in Australia and New Zealand, where the highest percentage of this activity occurs in relation to total land of any area in the world. East and north of the Caspian Sea in southern Russia lies the fifth and last major zone. Operating Units The operating units consist not only of the natural pasture land but also the ranch house and acreage (area) devoted for supplementary feed crops. Livestock ranching involves the largest operating units of any type of bio-culture. In the US, ranches frequently exceed thousand acres and in Wyoming, Nevada, Arizona, New Mexico and Texas, they often exceed 2,500 acres in size. One ranch in southern Texas encompasses 865,000 acres, over 1,000 miles2. But the world’s largest ranches are found in Australia, where several spread over 5,000 miles2; one Australian ranch covers an astonishing 12,000 miles2. Carrying Capacity of Units A close balance between man and nature occurs in livestock ranching areas, as over grazing can destroy the food supply. The concept of carrying capacity is often used to indicate this relationship. Carrying capacity refers to the number of animals a given amount of land can support with its natural vegetation. The variation is great. Over the dry near-desert area of the southwestern US, 100 acres or more may be required to supply forage necessary for just one steer (cattle). In steppes (grasslands) and mountain meadows, the carrying capacity generally varies from 25 to 75 acres per steer. On the eastern margins of the Great Plains, the capacity improves to 3 to 5 acres per steer. These figures can also be phrased in terms of Animal Units, whereby to measure carrying capacity, one steer is equated with one horse or 5 sheep. If an area has a carrying capacity of 10, a rancher can count on successfully raising to steer or ten horses or 50 sheep or any combination thereof, as long as the 10 unit figure is not exceeded. Population Densities in Ranching Regions Low population densities characterize livestock ranching regions. Density ranges of between 2 and 25 persons per sq. mile are normal. Settlements are typically small in size and a few in number. In the American west, these settlements are very widely separated. A spacing of 100 miles between communities often occurs, and in some instances this distance can increase to 300 miles, as it does in Nevada. Environmental Setting Most commercial ranching occurs in dry lands. Dry climates prevail in the five largest ranching areas. Precipitation is significant in its effect on both natural vegetation and alternative possibilities for bio-culture. Generally it is held that 10 to 20 inches of annual rainfall marks the limit for un-irrigated farming in the mid latitudes. Beyond that line, the drier regions are too risky for cropping and generally are devoted to livestock ranching. Most of the plants that can survive in dry lands are not valuable enough to cultivate. But animals can live off such scattered vegetation. This is the basic reason that animals husbandry rather than cropping is the prevailing form of bio-culture on dry land that is not irrigated. Livestock ranching occurs in regions of grassland and desert shrubs. The type of grass cover in ranch areas varies greatly through out the world. In the low latitudes are the tropical grass lands, generally termed Savannas – such as the Llanos of Venezuela, the Campos of Brazil and the Gran Chaco, region in South America, and encompassing part of Argentina, Paraguay, and Bolivia. Generally, these tropical grasses are tall, course and fibrous, so are not very edible, and their carrying capacity is low. Yet some tropical grasses which are softer and more palatable (tasty), can support animals fairly well and would provide rather good range land if their spreading could be encouraged. There is little direct correlation between ranching regions and landforms; ranching occurs on plains, hills, plateaus and mountains, in lowlands and in highlands. Variations in temperature are associated with a distinctive practice called transhumance, in which herders move their animals to different altitudes with a change in season. This system prevails in regions where the climate has one severe season say, a very cold winter. The usual practice is to graze the herd on lowland forage in the winter when the mountain pastures are inaccessible and then in summer to move the herd to the slopes to permit replenishment (supplying) of lowland grasses. This technique occurs in the sheep-grazing areas of southern Wyoming and western Colorado and in mountainous areas of Europe. Origin Livestock ranching is a new comer on the world map. Whereas herding has been practiced for millennia, commercial ranching is little more than 200 years old. Not until the period 1750 to 1800 did world markets generate enough demand for wool, hides, and meat, to support a commercial animal economy based on natural vegetation in the dry lands. The advent of refrigeration in the 1880s gave the industry another boost, specially by opening up the Argentinean products to world market. Relations with Farmers In two quite different ways, livestock ranchers find themselves involved with farmers. In some areas they shift their cattle to farmers in humid regions for fattening before final sale. This relationship holds particularly in North America, where the ranchers of various western states collaborate with corn belt farmers. On the other hand, as population has increased, the demand for food has risen, and new farms have been staked out, often on humid margins of range country. In this instance, the tillers (cultivators) of the soil have steadily invaded grazing lands, tempered primarily by the availability of irrigation water. DAIRY FARMING Introduction With the development and growth of big town and cities, this system came into practice. The large demand of dairy products from the urban areas lead to increase the area of supply and to intensify the method of production. Cattle is an important source of dairy products, like fluid milk, butter, evaporated and condensed milk, cheese, ghee, curd etc. Dairy cattle are often very important in mixed farming regions. A herd of dairy cattle focus the farmer’s attention to the exclusion of other activities; crops are grown, but only to supply feed for the stock, pasture is maintained, but only for the cattle to graze, and meadow is kept for the production of hay. The farm may sell liquid milk, as it does in southwestern England, or it may also make butter and cheese using the by-products of the creamery to feed pigs, as in the Netherlands and Denmark. Regions In subsistence farming areas, small quantities of dairy products are consumed and only around large cities, dairy industry of some magnitude has developed. But in east central America, North America, Western Europe, Eastern Australia, and New Zealand, dairy industry on a large scale has developed. Minor dairy regions include western US, eastern Argentina, middle Chile, the Union of South Africa and eastern Japan. Diary Products The dairy products are first raw milk and then a number of by-products of milk, chiefly cheese, butter, condensed milk and dried milk. There has been a great advance in the cleanness of market milk, consequently the supply of fresh milk in air tight bottles, tetra packs etc. to the thickly populated trade and industrial centers has increased considerably. Cheese, a condensed form of milk is a good substitute for meat; and butter is a fat, supplying all the vitamins which are generally absent in our daily ordinary food. All three of these major dairy products, particularly milk and butter, are valuable in the preparation of many other articles of food. The trade in butter and cheese, specially in the former, has increased immensely since the introduction of refrigeration into transportation and storage. Supplies come from far off countries now reach their destination without loosing their commercial qualities. Besides refrigerated dairy produce, a certain amount enters in commerce as tinned butter or condensed milk also. The supplies of these come mostly from Europe and Australia. Development The development of dairy industry is closely connected with the growth of large urban centers. Development of rapid means of transportation and the invention of refrigerator have made possible to extend the areas of dairy farming. It is now possible to transport fluid milk and cream to the market from distances of 100 miles or more. This led to the development of milk-sheds around larger cities. Butter and cheese can move from one continent to another by means of advanced technique of storing. Dairy farming in different Regions USA and Canada USA and Canada, the leading dairy countries of the world, have dairy industry almost around every large city. But the main dairy region has developed in southeastern Canada and northeastern USA from the Atlantic Seaboard to the state of Minnesota. The region enjoys humid continental climate with a growing season too short for many of the grains to mature. The severe long winter should have induced a period of inactivity for the farmers except for the development of dairy industry which can be practised indoor. The topography is hummocky and the soils are poor, best suited for grasses. The region is close to large urban centers which provide market for dairy products. Many migrants in that part of America had practiced dairy farming for generations in Europe. All these factors have combined together to make this region an important dairy farming region in the world. The USA is the leading producer of cheese and the second largest producer of milk and butter in the world. Europe Northwestern Europe has given lead to the world in the development of dairy industry on scientific lines. Many of the dairy cows have the homes in this part of the world. Even today, some of the most advanced districts in dairy industry are located in Europe. European countries together produce more cheese and butter than the remainder of the world. But the large population of Europe consumes more dairy products than they produce. Therefore Europe is a net importer of dairy products. Denmark’s leading industry is dairy farming. As one moves out from here, the importance of dairy farming decrease. Netherlands, Belgium, the British Isles, West Germany, northern France and Switzerland are other important dairy areas. Former USSR has developed a large dairy industry. It leads the world in production of milk and butter. New Zealand The dairy farming in New Zealand dates back to 1840 but the expansion of the industry awaited the invention of refrigerator in 1882. New Zealand is one of the leading suppliers of butter and cheese. Its chief market is the British Isles. New Zealand enjoys ideal climate for cattle raising. Mild winter makes year round pasturing possible, moist climate permits growth of grass and hay crops and cool temperatures are excellent for handling perishable products. Most of the dairy farms are located in the rolling plain of North Island. Like Denmark, the dairy industry is run on cooperative basis in New Zealand. Like USA, the dairy industry is highly mechanized here. Special attention is paid to grading. Australia Dairy farming though very important in Australia is not that important as in New Zealand. The production of dairy products greatly fluctuates. Australia exports large quantity of butter and cheese. UK is the chief market. Dairy industry is located in the southeastern Australia. Investment Elaborate buildings and expensive machinery require large capital investment and give dairy farms very high market values. A typical dairy farm today has several feed sites and machinery storage sheds. In addition to the dairy barn itself. Machinery needs for the dairy farm go far beyond those required for feeding, milking and cleaning responsibilities. The cost of bulk milk cooling and storage tanks alone can run into hundreds of thousands of dollars. In addition, dairy farms typically farms typically have several large tractors, plows, harvesters, wagons and trucks. Dairy animals themselves represent a large investment. Mature cows sold for milk production have a value of about $500 to $1,500. COMMERCIAL FARMING Introduction This type of farming, quite opposite to subsistence farming, indicates tillage of very big fields. Here large scale production is the main object because all requirements for raising huge crops are available. This farming is really practised on commercial basis, i.e., the growers raise different crops not for their own use or for home consumption but mainly for trade purposes – for exporting to other countries. In all the economically scientifically advanced countries like USA, Canada, Australia, former USSR and some west European countries, farming is commercialized. In such countries, agriculture has become one of the important industries. Countries like China, Brazil or Argentina are also developing their agriculture on the pattern of commercial farming. Characteristic Features On account of large scale production, the consequent economies are enjoyed. Cost of production has gone down. Production per acre has gone up tremendously. Rotation of crops under favorable weather and soil condition is also possible. Wide use of machinery has relieved man of his fatigue. More laborers are not required as machine does their work at the command of one man only. Geographical cooperation and coordination can remove scarcity and famine conditions as surplus area can now afford to send grains to those regions where either the crops fail or low yield results due to calamities of nature. Besides, where animal breeding is also taken in hand, quality dairy products are possible. Proper and speedy marketing facilities ensure prompt disposal of crops, other products and collection of required materials on the farms. Where facilities for refrigeration are necessary, they are made available as these farms are all electrified. Rationalization is another characteristic feature, i.e., all the necessary factors of production are employed in the best proportion in order to gain the best results, both from qualitative and quantitative aspects. Both intensive and extensive farming is practiced. In those countries where population pressure is not high on the land, extensive farming is possible, e.g., in Canada. Conversely, if the same field, due to its physical potentiality promises greater yield then intensive farming is resorted to, e.g., in the advanced countries of Europe. Implements and Products This farming has been symbolized with mechanization. Instead of old and crude methods or implements, latest machinery is used at all stages – since sowing of the seed upto harvesting. Big tractors and bull dozers have replaced the animal-drawn plows. The farmers are rich enough to use best quality seed and fertilizers. Chemical fertilizers and insecticides to kill injurious insects, pests etc. are invariably used. Machines do all watering of the farms with fine uniformity. The important crops raised under this farming are wheat, maize, rice, coffee, tea, jute, sugarcane, etc. Research Work Rich farmers, who are really businessmen, can and do arrange research work. Each big farm is equipped with a laboratory. Experiments on soil fertility, hybrid seeds, relation of crops, manure and their different uses on various soils, discovery of new crops etc. are made by qualified botanists, geologists and experts of agriculture. Advantages Commercial farming has revolutionized agriculture. Self-sufficiency is giving way to interdependence. Today Dundee (Scotland) looks to Bangladesh for raw jute, and Pakistan or India import wheat or rice from America, Australia or Canada in times of emergency. This is all due to large scale commercial farming. DRY FARMING Introduction It means to practice agriculture without irrigation in regions which have deficient rainfall. The main difference between dry farming and humid farming lies in the supply of water. In dry farming the supply of water is very small. The cost of agricultural crops under dry farming is usually high. Consequently, the problem of crop selection is very important. Only those crops are cultivated which can withstand drought season. The dry farming soils are generally found in parts where the average rainfall is from 10 to 20 inches (500 mm). Soils The typical dry farming soils are mostly sandy or silt loam and are located in regions where the average annual rainfall is from 10 to 20 inches. Dry farming soils are marked by great fertility, as there is no leaching of the soils in these areas. Methodology Water is the most vital condition of agriculture and, therefore, in dry farming its conservation and utilization is very important. To preserve water, deep ploughing is done soon after the harvest so that the soil may suck the greatest amount of water, whenever there is rainfall in future. In cold countries deep ploughing also checks the drifting of snow that may fall in winter. With a view to conserve the moisture, a layer of dust is spread over the surface of the soil. This layer of dust prevents water from being evaporated by the sun. If, after the harvest, land is left uncultivated, it is necessary to see that no weeds grow, otherwise they will absorb all the moisture of the soil. Crops Wheat is the most important food grain which is produced under dry farming. It is fairly drought-resistant and economic in its use of water. As the wheat has both spring and winter varieties, it is well-adopted to a wide range of climatic conditions that may occur in the dry farming lands. Oats, barley, rye and beans are other important crops grown chiefly as fodder crops. In the USA, cotton has become firmly established in dry farming. Grapes also adopt well to dry farming techniques. Areas The most important dry farming areas of the world are found in USA. Other countries where dry farming is practised are Canada and areas of western Asia and Africa. TERRACE FARMING This system is largely adopted in the warmer parts of the world. Under this method, the cutting of hill slopes into terraced field rising step-like above one another takes place. The terraced fields are irrigated with great facility. Terraced walls are usually from 5 to 8 ft. high but walls towards the top of the mountain are 15 to 18 ft. high. The formation of terraces needs much labor so this system is costly. Regions This system is mostly practised in mountainous areas of the world. In northern Pakistan, northern India, Nepal, Indonesia, China and in some other southeast Asian countries. Crops Corn and maize in Pakistan, paddy in China and Indonesia, tea and coffee in India etc. Stops Erosion During the 1960s, experimental work showed that contour planting and terracing would help preserve the slowly eroding steep slopes.
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Success is never achieved by the size of our brain but it is always achieved by the quality of our thoughts.
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#6
Tuesday, January 10, 2012
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Mechanized farming
MECHANIZED FARMING
Mechanized means to use machine to do something that used to be done by hand. Farming has been mechanized, reducing the need for labor and increasing the food supply as to meet the requirement of the growing population of the world. Agricultural machinery has got progressively larger. It is now feasible for one man to plough in excess of 10 hectares in a day with suitable machinery. In today’s modern world, even though God has permitted knowledge and learning to increase, the want of sufficient food continues as a distressing problem. It is estimated that 50% of the people on earth are undernourished. Famine and starvation continue to claim millions of lives every year. The continual increase in the world’s population adds to the woes stemming from this deficiency in our societies. This is in spite of the great advancement made in the last hundred years to keep pace with the need for food. Many of these advancements have been the result of the increase of knowledge, of which mechanized farming is one example. This approach requires capital investment. After World War II, mechanized farming permanently supplanted the old agricultural practices that depended on human labor in the fields. Pasture is land with lush herbaceous vegetation cover used for grazing of ungulates as part of a farm or ranch. Prior to the advent of mechanized farming, pasture was the primary source of food for cattle and sheep. It is still used to some degree. But it was effected by the mechanized farming. EQUIPMENT FOR MECHNAIZED FARMING: The inventions which made possible mechanized farming were the plow and reaper in 1837 and 1831 respectively. John Deere, the inventor of the steel plow, and Cyrus McCormick, the inventor of the reaper, both started large factories to make these basic farming implements. Other mechanized farming equipment was invented and manufactured, but it was not until the invention of the tractor and the gasoline-powered engine, that mechanized farming reduced the labor of farming. These inventions, if made available to the whole world, would increase the food supply. MECHANIZED FARMING ON THE RICE TERRACES Scarce labor and inappropriate farm machinery are among the major problems in sustaining the productivity of the Rice Terraces. Thus, the need to mechanize land preparation becomes imperative. In view of this, the Philippine Rice Research Institute (PhilRice) and the Central Cordillera Agricultural Programme (CECAP) developed a lightweight floating type power tiller for land preparation. This machine is called the "Super Curyat" tiller. The "Super Curyat" tiller can be disassembled and assembled easily. This feature eliminates difficulty in transporting the machine along steep terrain. 94 percent and 65 percent savings in time and cost, respectively, by using this mechanized method for rice terraces as compared with the traditional method. ADVANTAGES OF MECHNAIZED FARMING: 1. Time can be saved by using this method as machines can do more work in less time. 2. Workability of the workers are increased. 3. Cost of production can be reduced. 4. Food supply can be increased by using mechanized farming in the proper way. 5. Machines are substitute for labor. It requires less labor. 6. Labor is too expensive to do everything so by reducing the need for labor it reduces the cost. 7. Attract or retain farm staff. 8. Increase productivity of farm staff. 9. by using this method farmers can reap the economies of scale. DISADVANTAGES: 1. Mechanized farming requires capital investment 2. A high standard of management is required for the proper planning and timing of the field operations. 3. Redundancy - machinery for labor substitution. 4. Cost - finance, fuel etc. 5. Often needs highly skilled operator, increased wages 6. Environmental costs n
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Success is never achieved by the size of our brain but it is always achieved by the quality of our thoughts.
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#7
Tuesday, January 10, 2012
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Dry Farming
FARMING:
Farming was once the chief way of life in nearly every country. People cannot live without food, and nearly all their food comes from crops and animals raised on farms. Many other materials such as cotton and wool also come from plants and animals raised on farms. Not many people farm for a living any more, but farming remains the most important occupation in the world. DRY FARMING: A type of farming practiced in arid areas without irrigation by planting drought-resistant crops and maintaining a fine surface tilt or mulch that protects the natural moisture of the soil from evaporation. Dry farming is concerned with all phases of land use under semi-arid conditions without irrigation. The primary necessity is to be able to catch and efficiently use rainfall. This is often done by using fallow periods where precipitation is absorbed and stored. CONDITIONS FOR DRY FARMING: It is adopted in areas having an annual rainfall of approximately 15 to 20 in. (38.1-50.8 cm)—with much of the rainfall in the spring and early summer—where irrigation is impractical. Seeding rates are used that correspond to the soil water supply; management practices that minimize water loss and soil erosion are also utilized. The land is often summer-fallowed (not used for crops) in alternate years to conserve moisture. Dry-land crops must be either drought-resistant or drought-evasive, i.e., maturing in late spring or fall; special varieties of crops such as wheat, barley, corn, sorghum, and rye are often used. Dry farming is the profitable production of useful crops, without irrigation, on lands that receive annually a rainfall of 20 inches or less. In districts of torrential rains, high winds, unfavorable distribution of the rainfall, or other water-dissipating factors, the term "dry-farming" is also properly applied to farming without irrigation under an annual precipitation of 25 or even 30 inches. There is no sharp demarcation between dry- and humid-farming. When the annual precipitation is under 20 inches, the methods of dry-farming are usually indispensable. When it is over 30 inches, the methods of humid-farming are employed; in places where the annual precipitation is between 20 and 30 inches, the methods to be used depend chiefly on local conditions affecting the conservation of soil moisture. Dry-farming, however, always implies farming under a comparatively small annual rainfall. DIFFERENT NAMES OF DRY FARMING: The term "dry-farming" is, of course, a misnomer. In reality it is farming under drier conditions than those prevailing in the countries in which scientific agriculture originated. Many suggestions for a better name have been made. "Scientific agriculture" has-been proposed, but all agriculture should be scientific, and agriculture without irrigation in an arid country has no right to lay sole claim to so general a title. "Dry-land agriculture," which has also been suggested, is no improvement over "dry-farming," as it is longer and also carries with it the idea of dryness. Instead of the name "dry-farming" it would, perhaps, be better to use the names, "arid-farming." "semiarid-farming," "humid-farming," and "irrigation-farming," according to the climatic conditions prevailing in various parts of the world. However, at the present time the name "dry-farming" is in such general use that it would seem unwise to suggest any change. It should be used with the distinct understanding that as far as the word "dry" is concerned it is a misnomer. PROBLEMS OF DRY FARMING: The dry-farmer should have following points in mind: know with comparative accuracy the annual rainfall over the area that he intends to cultivate. must have a good acquaintance with the nature of the soil. In fact, a knowledge of the soil is indispensable in successful dry-farming. 1. STORAGE OF PRECIPITATION IN SOIL: Since, under dry-farm conditions, water is the limiting factor of production, the primary problem of dry-farming is the most effective storage in the soil of the natural precipitation. Only the water, safely stored in the soil within reach of the roots, can be used in crop production. 2. PROBLEM OF KEEPING WATER IN THE SOIL: Of nearly equal importance is the problem of keeping the water in the soil until it is needed by plants. During the growing season, water may be lost from the soil by downward drainage or by evaporation from the surface. It becomes necessary, therefore, to determine under what conditions the natural precipitation stored in the soil moves downward and by what means surface evaporation may be prevented or regulated. The soil-water, of real use to plants, is that taken up by the roots and finally evaporated from the leaves. A large part of the water stored in the soil is thus used. The methods whereby this direct draft of plants on the soil-moisture may be regulated are, naturally, of the utmost importance to the dry-farmer, and they constitute another vital problem of the science of dry-farming. 3. DIFFERENT AMOUNT OF WATER REQUIRED BY DIFFERENT PLANTS: The relation of crops to the prevailing conditions of arid lands offers another group of important dry-farm problems. Some plants use much less water than others. Some attain maturity quickly, and in that way become desirable for dry-farming. Still other crops, grown under humid conditions, may easily be adapted to dry-farming conditions, if the correct methods are employed, and in a few seasons may be made valuable dry-farm crops. The individual characteristics of each crop should be known as they relate themselves to a low rainfall and arid soils. 4. ADAPTING THE CROP TREATMENT TO ARID CONDITIONS: After a crop has been chosen, skill and knowledge are needed in the proper seeding, tillage, and harvesting of the crop. Failures frequently result from the want of adapting the crop treatment to arid conditions. 5. PROPER USE OF CROP: After the crop has been gathered and stored, its proper use is another problem for the dry-farmer. The composition of dry-farm crops is different from that of crops grown with an abundance of water. Usually, dry-farm crops are much more nutritious and therefore should command a higher price in the markets, or should be fed to stock in corresponding proportions and combinations. The fundamental problems of dry-farming are, then, the storage in the soil of a small annual rainfall; the retention in the soil of the moisture until it is needed by plants; the prevention of the direct evaporation of soil-moisture during; the growing season; the regulation of the amount of water drawn from the soil by plants; the choice of crops suitable for growth under arid conditions; the application of suitable crop treatments, and the disposal of dry-farm products, based upon the superior composition of plants grown with small amounts of water. Around these fundamental problems cluster a host of minor, though also important, problems. When the methods of dry-farming are understood and practiced, the practice is always successful; but it requires more intelligence, more implicit obedience to nature's laws, and greater vigilance, than farming in countries of abundant rainfall. IMPORTANCE OF DRY FARMING: Dry farming refers to a set of techniques for raising crops in a semi-arid climate. It involves the maintenance of soil conditions that encourage moisture conservation, including tillage and drought resistant crop varieties. Dry farm areas follow a summer fallow cropping practice and are tilled every other year to conserve moisture. It is profitable production of useful crops without irrigation on lands which receive less than 20 of rain or modified as to make use of every opportunity to conserve moisture.
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Success is never achieved by the size of our brain but it is always achieved by the quality of our thoughts.
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#8
Tuesday, January 10, 2012
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Salinity of the oceans:
SALINITY OF THE OCEANS:
INTRODUCTION: Sea water is salty. This is due to the presence of a large variety of salts in it. It has been estimated that one cubic kilometer of sea water contains an average of 41 million tons of dissolved salts. If the entire salt of the ocean water is uniformly spread over the earth it will cover the entire globe with 150 meter thick layer of salts. Similarly is expressed in terms of amount per thousand. In other words, it may be expressed as the number of grams of dissolved salts in thousand grams (or one kilogram) of sea water. The average salinity of the water is about 35 per thousand or 35 %. This means that one kilogram of sea water contain on an average 35 grams of dissolved salts ORIGIN OF SALT IN THE SEA: The salt in the sea is no doubt derived in part from rivers. River-waters always hold a certain amount of material in solution and most of this is carried into the sea. It is estimated that each year the rivers contributed a tiny fraction 5.4 × 10-8, of the dissolved solids in the ocean. If this were the way in which the sea originally became salt, sea water would be only a concentrated river-water. But it is by no means clear that the whole of the salt has come from rivers. There is a considerable difference between the salts in the sea water and those in average river-water. In the former by far the greater part consists of lime (calcium). Considering the very subordinate part played in sea water by carbonate of lime, it appears a first sight improbable that sea water could be produce by any concentration of the water of existing rivers. But this, objection is not decisive. A very large number of animals which live in the sea, such as Molluses and Corels etc, form their shells or skeletons of carbonate of lime which they abstract from the water. Therefore, the carbonate of lime brought into the sea is continually being used up, while the sodium chloride is left behind. Possibly the difference in the relative abundance of carbonates and chlorides in sea and river-water may be accounted for in this way: but there are other differences also. In the water of rivers to judge form actual analysis, the Sulphates exceed the chlorides and the proportion of potassium to sodium is very much greater than in the water of the sea. The composition of river-water however, varies greatly: and most of the rivers of the world have not yet been chemically examined. The analyses which have been made certainly suggest either that the salts of the sea have not been derived entirely from rivers or that in past times the composition of river-water must have been very different. But until a much larger series of analysis is available from rivers in the entire globe, it is unsafe to assume that the average composition of river-water is even approximately known. IMPORTANCE OF SLAINITY: Similarly, it is very important property of the ocean water. it determines among other features, compressibility, thermal expansion, temperature, density, absorption of insolation, evaporation and humidity. The amount of salinity also greatly influences the composition and movement of the ocean water, the distribution of sea fish, sea animals and plankton FACTORS EFFECTING SLAINITY: Salinity of the ocean water depends upon the following factors:
1.TEMPERATURE: High temperature results in increase of evaporation, during the process of evaporation fresh water evaporates leaving the salts behind. The vapor in the air falls as precipitation due to condensation and dissolve salt from the soil as it follows to the ocean. The dissolved salts are then deposited in sea. This process continues and increase salinity in the oceans water. 2. FREASH WATER FROM THE RIVERS: The inflow of fresh waters from the rivers into the seas the proportion of salinity in the ocean water, for example, the salinity of black sea is only 17% because large quantities of fresh water are grown with it by rivers Danube, Dneister, Deneiper and Don. So much fresh water is thrown in the Gulf of Bothniaby order Vistula. Etc., that its salinity is reduced to 2%. RAINFALL: High amount of rainfall bring large quantity of fresh water and reduce salinity. This is the reason that there is no proportion of salinity in the equatorial region. MELTING OF ICE: Where there ice melts near sea it provides a lot of fresh water and reduces salinity. The low salinity of the North Seaand the Gulf of Bothniais partially due to ice melt. EVAPORATION: During evaporation fresh water evaporates leaving the salt in the ocean. Thus, when evaporation is high salinity is also high. The salinity in this case rises extra ordinary high when fresh water supply. In the red sea, there is high evaporation and low amount of fresh water supply. Therefore, the salinity in the red sea is high and it amounts to 40%. The salinity of salt lake in Utah (USA), Dead Sea and Won Lake of Turkey is 220%, 228% and 330% respectively due to high rate of evaporation. DISTRIBUTION OF SLAINITY: Some important facts about the world distribution about the salinity are given below.
1. HIGH LSIANITY AT THE TROPICS: The greater proportion of salt is found in two areas which lie about the tropics of Cancer and Capricorn. From these regions the salinity decreases both toward the equator and poles wards. The high salinity at the tropics is due to the high degree of evaporation resulting from the clear sky and bright sunshine. The vapor which is formed here is carried away by winds and condenses else where. 2. LOW SLAINITY AT THE EQUATOR: At the equator, the high heavy equatorial rains dilute the surface waters and the cloudiness of the region some what retards evaporation. About the months of the Niger and the Congo, the salinity is particularly low, on account of the volume of fresh water poured out upon the surface by these rivers. Since fresh water is lighter than salt water (of the same temperature) water of rivers may float for sometime upon the sea before complete mixture takes place. 3. LOW SLAINITY IN POLAR AREA: From the tropics towards the poles, the salinity gradually decrease till it is very low, in the polar areas this is due to supply of fresh water by ice melt and also due to low evaporation because of low temperature. 4. TENDENCY FROM EAST TO WEST: There is a tendency for salinity to increase from east to west. PARTIALLY ENCLOSED SEAS: Seas like the Mediterranean and the Baltic, which communicate with the ocean only by narrow straits, show much greater differences in salinity. In the Mediterranean at the straits of Gibraltarthe salinity is about 36.5% but it increases eastwards and on the Syrian coast it exceeds 39%. At the southern end of the Red Sea the salinity is about 36.5%. But it rises towards the Gulf of Suez, where it is more than 41%. These are example of sea with a higher salinity than any part of the open ocean. In the black sea on the other hand the surface salinity over the greater part is only 18% or 18.5% and in the sea of Azob it is considerably less. In the Baltic Sea the salinity at the entrance varies considerably and is influenced among, other things, by the direction of the winds and perhaps by the differences between the atmospheric pressure inside and outside the sea. With the low pressure inside and outside the sea there is usually a current from the Baltic Seawhich is then higher. The converse also is true about the island of Rugen the salinity is only 7% or 8% and it decrease northwards. At the head of the Gulf of Bothnia and Finland it is often less than 2% and in spring the water is particularly fresh. The salinity of these seas, like that of the Open Ocean of itself depends upon the relation between the supply of fresh water and the loss by evaporation which does not remove the salts. In the Mediterraneanand the Red Sea the evaporation is great and the rainfall small. The red sea is practically without rivers. The Mediterranean receives the waters of the Rhone, the Po and other rivers, but the total amount is small compared with the area of the sea. In theBlack sea evaporation is less than the Mediterranean and many large rivers such as the Danube, the Dneister, the Dnieper and the Don bring a much larger supply of fresh water supply in proportion the size of the sea. In the Baltic Sea also, which lies in a colder region, evaporation is comparatively slow. A large amount of fresh water is received from the numerous rivers of Swedenand Northern Russia especially during the melting of the snow in spring and early summer. IN LANDSEAS AND LAKES: In a lake which has an outlet there is no tendency for the water to be more saline than that of the rivers which flow into it, for the salt which they bring is carried away by the river that flows out. Absence of an outlet implies that evaporation is at least equal to the supply, for otherwise the depression would fill up until the water overflowed in such cases there is no escape for the salts brought in by the rivers which enter the lake, and water must gradually grow more and more saline. The degree of salinity will depend in part upon the length of time that the lake has existed without an outlet. Even in the same lake, however, there may be a considerably variations. In the northern part of the Caspian the salinity is less than 14%, while in the shallow gulf of Karabugas, which is connected with the rest of the Caspian only by a narrow and shallow opening the salinity reaches 170%. In this gulf evaporation is rapid and there is a constant inward steam of water from the Caspian to make up for the loss. The Dead Seais the saltiest of the larger lakes, the salinity reach 237.5%, but even this is exceeded by some of the smaller lakes in the dry region of the globe. In most of inland seas and lakes the composition of the dissolved salt is not the same as in ordinary sea water. Sodium chloride is usually, though not always abundant, but other constituents play a more important part then in the oceans.
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Success is never achieved by the size of our brain but it is always achieved by the quality of our thoughts.
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#9
Tuesday, January 10, 2012
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Classification of Map projection
Attempt a classification of Map Projections and write the merits and demerits of any
Two of the following map projections: a. Bonne’s b. Mercator’s c. Mollweides MAP PROJECTION: A map projection is a systematic representation of the parallels of latitude and the meridians of longitude of the spherical surface of the earth on a plane surface. In other words, it is a method of representing the parallels and the meridians of the earth on a plane surface. The network of the parallels and the meridians so formed is called a graticule. On our earth resembles a sphere. Therefore, a globe being spherical in shape represents the earth truly. Thus a globe is a true representation of the earth. In other words, a globe is true map of the earth. Since a map represents a flat surface and a globe a spherical surface, the shape of the network of the parallels and the meridians on a map is always different from that on a globe. There are a number of methods of transferring the parallels and the meridians of a globe on a plane surface, i.e., constructing map projections. The shape of the network of the parallels and meridians drawn by one method differs from that by the other methods. Therefore, there is a great variety of graticules. A variety in the graticules is necessary to meet various specific purposes. Earth relationships such as shapes, areas of countries and direction of one place from the other, are not maintained on map. A map projection showing the area of a globe correctly will not maintain the shapes and directions of the areas truly. Thus it is not possible to construct a map projection showing the globe truly and there is always some distortion in the shape of the graticules. Being unable to acquire all the qualities of a globe, a map projection can’t be used as a complete substitute for a globe. CLASSIFICATION OF MAP PROJECTIONS: There are two ways of classifying map projections. The first is based on the principle involved in their mode of development and the second is based on the group or family to which they belong.
Under this scheme we have flowing map projections:
I. PERSPECTIVE MAP PROJECTIONS: The word perspective in the usual sense means the art of representing solid objects on a flat surface in such a way as to give the same impression of relative distance, size, etc., as the objects themselves do when viewed from a certain point. Thus in a perspective map projection the parallels and the meridians of the globe are represented on a surface geometrically from a point. There are three types of surfaces on which parallels and meridians of the globe are transferred and they are 1. A cylinder in which the globe is placed 2. A come which is placed on a globe in such a way that its apex is vertically above the north or South Pole 3. A plane which is placed tangentially to the globe at the north and South Pole. The cylinder and the cone being developable surfaces are unrolled into flat surfaces. The projection developed on a cylinder is called a cylindrical perspective projection, that developed on a cone is called a conical perspective projection and that developed on a plane is called a zenithal perspective projection. There are three positions of the view point. They are
Anyone of these three positions is selected for the viewpoint. The position of the viewpoint and the nature of the surface are selected with a view to developing a particular property in the projection. In actual practice we draw rays from the view point on to the surface In pure form very few perspective map projections are useful. To make them useful they have been greatly modified. TYPES OF PERSPECTIVE PROJECTIONS: Following are the perceptive projections: ZENITHAL PERSPECTIVE PROJECTION:
This is the projection in which the surface is plane placed tangentially at a pole of the globe and the ‘viewpoint’ at the centre of the globe.
In this projection the surface is plane placed tangentially at a pole of the globe and the viewpoint at the other pole of the globe
In this projection the surface is a plane placed tangentially at a pole of the globe and the viewpoint at infinity. II. NON PERSPECTIVE MAP-PROJECTIONS: The perspective projections being of limited use have been modified to develop useful properties. Being modified to a great extent they remain no longer geometrical and are, therefore, known as non-perspective projections. They are so modified as to acquire any one or more of the following useful properties:
The non-perspective map projections since meet a number of requirements are far more useful and, therefore, more important than the perceptive map projections. TYPES OF NON- PERSPECTIVE PROJECTIONS: Following are the non-perspective projections: 1. CYLINDRICAL NON- PERSPECTIVE MAP PROJECTIONS: i. Simple cylindrical projection ii. Cylindrical equal-area projection. iii. Mercator’s or cylindrical orthomorphic projection i. SIMPLE CYLINDRICAL MAP PROJECTION This is a very simple projection in which both the parallels and the meridians are represented by straight lines at right angles to one another and are drawn at their true distance apart. They thus form a series of square. In this projection the distances along the meridians and the equator are correct but those along the parallels are more and more exaggerated towards the poles, which are extended to be of the same length as the equator. ii. CYLINDRICAL EQUAL-AREA MAP-PROJECTION The cylindrical equal-area projection is a real projection in the geometrical sense. In it the planes of the parallels are imagines to be extended to meet the circumscribing cylinder which touches the globe along the equator, and so when the cylinder is infolded, the representations of the parallels are straight lines which are parallel to the equator, and are close together towards the poles. The meridians are also straight lines at right angles to the parallels and are spaced at equal distances, as in the simple cylindrical. iii. MERCATOR’S OR CULINDRICAL ORTHOMORPHIC MAP PROJECTION This projection named after its inventor, was devised by Gerardus Mercator, a Dutch, in 1569 and used by him for a world map. It is based upon a mathematical formula. The meridians on the simple cylindrical projection and the cylindrical equal-area projection don not converge towards the poles. They are equi-distant throughout these projections, i.e., the distances between the meridians increases towards the poles in these projections 2. CONICAL MAP PROJECTIONS: i. SIMPLE CONICAL WITH ONE STANDARD PARALLEL: In this projection the cone touches the globe along a chosen parallel called the standard parallel, which passes through the middle of the area. The meridians are all straight lines converging to a point, the vertex of the cone, which is beyond the North Pole above the top of the map. They are at their true distances apart along the standard parallel. The parallels are all equidistant circular arcs drawn with the vertex of the cone as the center. The distance between any two parallels represents the true distance between them on the globe. ii. SIMPLE CONICAL PROJECTION WITH TWO-STANDARD PARALLEL. This projection is a slight modification of the simple conical with one standard parallel. In this, instead of one, take two standard parallels, one towards the middle of the upper half and the other towards the middle of the lower half of the map. Like the simple conic with one standard parallel, all the parallels are at their true distances apart and are represented buy concentric circular arcs whose radii from the meridians. Thus all the meridians are correct to scale. iii. BONNE’S PROJECTION: It is a modified conical projection with one standard parallel. It was invented by Rigobert Bonne (1727-1795). A French cartographer. In construction it is very similar to the simple conical projection with one standard parallel. The central meridian is drawn straight and is divided truly, and through the points off division the parallels are drawn as concentric circles as in the simple conical, but the meridians are not straight lines joining the vertex of the cone to the points of division of the standard parallel. Instead of this al the parallels are made of the exact lengths of the corresponding parallels on the globe, and divided truly like the standard parallel. Then the meridians are formed by drawing curves through the corresponding points on each parallel. iv. POLYCONIC PROJECTION: In this projection each parallel is constructed in the same way as the chosen standard parallel in the simple conic. The meridians are drawn as in Bonne’s. The parallels are, therefore, circular arcs, true distances part along the central meridian, but diverging from one another on either side of the central meridian, as each is drawn from a different centre. The central meridian s a straight line divided truly, while the other meridians are curves, the curvature being slight near the central meridian but increasing rapidly after the first 30 degrees of longitude. v. INTERNATIONAL PROJECTION: This projection is very useful modification of the Polyconic, and is employed in one-in-a-million international map of the world, according to the decisions of the international map committee (1909). The map consist of 2,222 sheets, each covering 6 degree of longitude and 4 degree of latitude below the 60th parallel, and 12 degree of longitude and 4 degree of latitude above it up to the 88th parallel, the two sheets of the polar areas are circular, each being 4 degree in diameter. 3. ZENITHAL NON-PERSPECTIVE MAP PROJECTIONS: i. Zenithal equidistant projection. ii. Zenithal equal-area projection. i. ZENITHAL EQUIDISTAND PROJECTION: This is a very common projection for polar areas and is very easy to draw. In the polar scale, of the net represents the pole and the parallels are drawn from it as concentric circles, at correct distances apart. The meridians are represented by straight lines drawn from the center at the required interval. ii. ZENITHAL EQUAL-AREA PROJECTION In the polar-zenithal equal area projection, like the zenithal equidistant, the meridians are radiating straight lines and the parallels are concentric circles, but the distance between the parallel circles are reduced in the same proportion as the scale along the parallels is too large. The parallels are thus closer together away from the centre. III. CONEVNTIONAL PROJECTIONS: These projections do not fall into the systems of cylindrical, conical and zenithal projections. In these projections, the parallels and the meridians are drawn arbitrarily so as to make the graticule of a projection more useful for specific purposes. They are drawn generally for showing the whole world. TYPES OF CONVENTIONAL PROJECTIONS: Following are the conventional projections:
This is a particular case ofBonne’s projection where equator is taken as the standard parallel. Therefore, all its properties are also similar. The equator and the central meridians are straight lines at right angles to each other and divided truly. The parallels are also straight lines parallel to the equator and are divided truly for the meridians intervals. The meridians are curves drawn through the corresponding points on the several parallels.
This projection is invented by Karl B. Mollweide in 1805. It is also known as homolographic projection. “Homolographic” is a word often used to mean “equal-area”, a property that this projection possesses. One hemisphere is outlined by a circle; the other hemisphere is divided into two parts and added with an elliptical outline to either side of the circle. All other meridians, except the straight central meridian, are halves of ellipses. The equator is twice as long as the central meridian, which is also true on a globe.
Both the Mollweide’s and Sanson-Flamsteed’s projections can be interrupted to avoid distortion—the chief drawback of these projections. Breaks can be made in those parts which are not material, e.g. in the case of continents, the breaks could occur at the pecans. The idea is to show only the best part of the projection with each land mass having its own central meridians; hence the word “recentred” means. In other words, they may be regarded as Mollweide’s or Sanson-Flamsteed’s projection with several centered meridians.
Thisis a purely conventional or arbitrary projection which has no special properties except that it is very easy to make. It is often used in atlases for the map of the world in hemispheres. A circle is drawn to represent each hemisphere, its horizontal diameter representing one-half of the equator and the vertical diameter the central meridian. The meridians are arcs of circles, concave to the central meridian, and spaced at equal intervals along the equator, while the parallels are arcs of circles convex to the equator and spaced at equal intervals along the central and the bounding meridians.
They are
CYLINDRICAL MAP PROJECTION: In these projections, the parallels and the meridians of the globe are transferred to a cylinder which is a developable surface. This class of projections is most suitable for maps of the equatorial regions, and so the more useful of them are (non-perspective) equatorial, that is where the cylinder touches the equator. Some of them are also used for maps of the world on a single she CONICAL MAP PROJECTIONS: The parallel and the meridians of a globe are transferred to a cone placed on the globe in such a way that its vertex is above one of the poles and it touches the globe along a parallel. The parallel along which the cone touches the globe is called a standard parallel. The cone is unrolled into a flat surface. The conical projection is formed. ZENITHAL MAP PROJECTION: These are the projections made on a plane touching the globe at any suitable point. The plane is usually made to touch one of the poles or some point on the equator and in oblique cases a point intermediate between the equator and the poles. It is most suitable for showing polar areas. The zenithal or azimuthal, group of projections includes all types that are centered about a point and have a radial symmetry. i. MERCATOR’S PROJECTION: This projection named after its inventor, was devised by Gerardus Mercator, a Dutch, in 1569 and used by him for a world map. It is based upon a mathematical formula. The meridians on the simple cylindrical projection and the cylindrical equal-area projection don not converge towards the poles. They are equi-distant throughout these projections, i.e., the distances between the meridians increases towards the poles in these projections. Mercator’s devised a mathematical formula by virtue of which he placed the parallels increasingly father apart towards the poles thereby increasing the lengths of the meridians but taking care that the increase in the lengths of the meridians was in the same proportion in which the lengths of the parallels increased. By doing so he got a true orthomorphic projection. The projection is, therefore, also called the cylindrical orthomorphic projection. In this projection, as in simple cylindrical projection, the parallels and the meridians are represented by straight lines at right angles to one another, and the meridians are spaced at equal distances. But to preserve the shapes of areas, the distance along the meridians (i.e., between the parallels) are elongated. In various latitudes in proportion to the stretching of the parallels, all of which are represented by exaggerated lengths, all being equal to the equator. In other words, at any latitude the meridians are stretched towards the poles to the same extent as they are done east and west to become parallel to one another. The scale along the meridians is increased in the same proportion as it is done along the parallels, so that it is the same north and south as it is east and west. MERITS:
DEMERITS: 1. The scale along the parallels and the meridians increases rapidly towards the poles. There being a great exaggeration of scale along the parallels and the meridians in high latitudes for this reason, the polar areas cannot be shown satisfactorily on this projection. 2. Poles cannot be shown on this projection because the exaggeration in the scales along the 90º parallel and the meridians touching them is infinite. 3. Because of infinite stretching towards the poles, this map fails completely to show how the land areas of North America, Asia and Europe are grouped around the polar area. In the mind of inexperienced user, it may enhance a false sense of isolation between inhabitants of these lands. 4. The Mercator’s projection is orthomorphic. it preserves shapes for small areas. As the scale changes from latitude to latitude the shapes of bigger areas are distorted ii. BONNE’S PROJECTION: It is a modified conical projection with one standard parallel. It was invented by Rigobert Bonne (1727-1795). A French cartographer. In construction it is very similar to the simple conical projection with one standard parallel. The central meridian is drawn straight and is divided truly, and through the points off division the parallels are drawn as concentric circles as in the simple conical, but the meridians are not straight lines joining the vertex of the cone to the points of division of the standard parallel. Instead of this al the parallels are made of the exact lengths of the corresponding parallels on the globe, and divided truly like the standard parallel. Then the meridians are formed by drawing curves through the corresponding points on each parallel. MERITS:
DEMERITS: The shapes away from the central meridians are distorted, the distortion increasing away from the central meridians. The shapes in the margins of the projection showing a large area such as Asia are much distorted. Therefore, this projection maintains shapes satisfactorily along with its equal-area property if areas are small and compact and have not large longitudinal extent. Hence, the projection is not orthomorphic and the shapes are not well preserved. This projection is ill adapted for countries having great extent in longitude. iii. MOLLWEIDES HOMOLOGRAPHIC PROJECTION: This projection is invented by Karl B. Mollweide in 1805. It is also known as homolographic projection. “Homolographic” is a word often used to mean “equal-area”, a property that this projection possesses. One hemisphere is outlined by a circle; the other hemisphere is divided into two parts and added with an elliptical outline to either side of the circle. All other meridians, except the straight central meridian, are halves of ellipses. The equator is twice as long as the central meridian, which is also true on a globe. Parallels are straight, horizontal lines, becoming more closely spaced towards the poles. The spacing of parallels, so adjusted as to give the map equal-area properties, is obtained by an individual method. In this projection all the meridians are ellipses excepting the central and the 90th meridian which are the special cases when the ellipse respectively becomes a straight line and a circle. The parallelsare all straight lines parallel to the equator, but are not spaced at equal intervals. The distance between the parallels gradually decreases as the latitude increases. MERITS:
DEMERITS:
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Success is never achieved by the size of our brain but it is always achieved by the quality of our thoughts.
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#10
Tuesday, January 10, 2012
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Merit and Demerits of Map Projection
Describe briefly different types of map projections. Discuss merits and demerits of each. Select a map projection for distribution of winds and ocean currents giving detailed reasoning for the same.
MAP PROJECTION: A map projection is an orderly system of parallels and meridians used as a basis for drawing a map on a flat surface. The fundamental problem is to transfer the geographic grid from its actual spherical form to a flat surface in such a way as to present the earth’s surface or some part of it in the most advantageous way possible for the purpose desired. In other words, it is a method of representing the parallels and the meridians of the earth on a plane surface. The network of the parallels and the meridians so formed is called a graticule. TYPES OF MAP PROJECTIONS: Map projections are of the following types.
1. CYLINDRICAL MAP PROJECTION: In these projections, the parallels and the meridians of the globe are transferred to a cylinder which is a developable surface. In cylindrical projections we presume that a cylinder surrounds the globe just touching it round the equator or any other great circle (a great circle is a circle the plane of which passes through the centre of the globe. Its plane divides the globe into two equal parts.) The meridians and the parallels are first transferred to the internal surface of the cylinder and then it is unfolded and developed to form a flat rectangular surface. The network thus obtained is on a cylindrical projection. On this surface: 1. The parallels are straight lines. Each parallel is equal to the length of the equator. Thus, the parallels are longer than the corresponding parallels on the globe. 2. The meridians are straight lines. They intersect the equator at right angles and they are equi-spaced in all latitudes. 3. The length of the equator on the cylinder is equal to the length of the equator on the globe. Therefore, these projections are quite suitable for showing equatorial regions. In this type the meridians and the parallels are represented by straight lines at right angles to one another. The lengths of the parallels are exaggerated in increasing proportions towards the poles, each parallel being equal to the equator. The distances between any two meridians are thus the same in all latitudes as on the equator. This class of projections is most suitable for maps of the equatorial regions, and so the more useful of them are (non-perspective) equatorial, that is where the cylinder touches the equator. Some of them are also used for maps of the world on a single sheet. TYPES OF CYLINDRICAL PROJECTIONS: Following are the main types of cylindrical map projections.
SIMPLE CYLINDRICAL PROJECTION: This is a very simple projection in which both the parallels and the meridians are represented by straight lines at right angles to one another and are drawn at their true distance apart. They thus form a series of square. In this projection the distances along the meridians and the equator are correct but those along the parallels are more and more exaggerated towards the poles, which are extended to be of the same length as the equator. When this projection is made transverse so that the cylinder touches the central meridian of a country instead of the equator, it becomes a useful projection known as Cassini’s. it is used for one-inch-to-a-mile maps of England and six-inches-to-a-mile maps of the British Isles. MERITS OF SIMPLE CYLINDRICAL PROJECTION: 1. The distances between the parallels and those between the meridians remain the same throughout the projection. 2. All parallels are of the same length and every one of them is equal to the length of the equator. 3. The length of the equator on this projection is equal to the length of the equator on the globe. Therefore the scale along the equator is correct. 4. All the meridians are of the same length and every one of them is equal to half the length of the equator on this projection. Therefore, scale is correct along all the meridians. For this reason, a narrow strip of land running in the north-south direction and crossing the equator is shown fairly correctly on this projection. This projection is used for showing a railway connecting Cairo (Egypt) with Durban (Republic of South Africa) because of these towns are located near 31 degree meridian. 5. A narrow belt along the equator can be shown fairly correctly on this projection. Since it is neither equal-area nor orthomorphic, maps on this projection are used for general purpose. DEMERITS:
The cylindrical equal-area projection is a real projection in the geometrical sense. In it the planes of the parallels are imagines to be extended to meet the circumscribing cylinder which touches the globe along the equator, and so when the cylinder is infolded, the representations of the parallels are straight lines which are parallel to the equator, and are close together towards the poles. The meridians are also straight lines at right angles to the parallels and are spaced at equal distances, as in the simple cylindrical. In this projection the scale along the meridians decreases rapidly north and south, as the distance between the parallels are of the same length throughout, though their real lengths diminish to zero at the poles. Therefore, on account of the inequality of scales, along the meridians of the parallel, the shapes are distorted and the projection is far from being orthomorphic. it is however, equal-area, as the area of a zone of a sphere is equal to that of the zone of the cylinder of the same height. Every zone of the projection thus represents the corresponding zone of the sphere in area. MERITS:
DEMERITS: 1. In the polar areas, the parallels are markedly stretched in the east-west direction and the meridians are shortened greatly in the north-south direction. Consequently the countries are stretched in the east-west direction and compressed in the north-south direction. 2. The scale along the parallels increases more and more away from the equator, for all the parallels are of the same length throughout, though their real lengths diminish to zero at the poles. Therefore, on account of the inequality of scales, along the meridians of the parallel, the shapes are distorted. the shapes of the countries are distorted increasingly towards the poles and the projection is far from being orthomorphic. The distortion in the shapes of tropical countries is almost negligible. . CYLINDRICAL ORTHOMORPHIC OR MERCATOR’S PROJECTION: This projection named after its inventor, was devised by Gerardus Mercator, a Dutch, in 1569. The meridians on the simple cylindrical projection and the cylindrical equal-area projection don not converge towards the poles. They are equi-distant throughout these projections, i.e., the distances between the meridians increases towards the poles in these projections. Mercator devised a mathematical formula by virtue of which he placed the parallels increasingly father apart towards the poles thereby increasing the lengths of the meridians but taking care that the increase in the lengths of the meridians was in the same proportion in which the lengths of the parallels increased. By doing so he got a true orthomorphic projection. The projection is, therefore, also called the cylindrical orthomorphic projection. In this projection, as in simple cylindrical projection, the parallels and the meridians are represented by straight lines at right angles to one another, and the meridians are spaced at equal distances. But to preserve the shapes of areas, the distance along the meridians (i.e., between the parallels) are elongated. In various latitudes in proportion to the stretching of the parallels, all of which are represented by exaggerated lengths, all being equal to the equator. In other words, at any latitude the meridians are stretched towards the poles to the same extent as they are done east and west to become parallel to one another. The scale along the meridians is increased in the same proportion as it is done along the parallels, so that it is the same north and south as it is east and west. MERITS:
DEMERITS: 1. The scale along the parallels and the meridians increases rapidly towards the poles. There being a great exaggeration of scale along the parallels and the meridians in high latitudes for this reason, the polar areas cannot be shown satisfactorily on this projection. 2. Poles cannot be shown on this projection because the exaggeration in the scales along the 90º parallel and the meridians touching them is infinite. 3. Because of infinite stretching towards the poles, this map fails completely to show how the land areas of North America, Asia and Europe are grouped around the polar area. In the mind of inexperienced user, it may enhance a false sense of isolation between inhabitants of these lands. 4. The Mercator’s projection is orthomorphic. it preserves shapes for small areas. As the scale changes from latitude to latitude the shapes of bigger areas are distorted 2. CONICAL MAP PROJECTIONS: The parallel and the meridians of a globe are transferred to a cone placed on the globe in such a way that its vertex is above one of the poles and it touches the globe along a parallel. The parallel along which the cone touches the globe is called a standard parallel. The cone is unrolled into a flat surface. The conical projection is formed In it usually, the meridians are straight lines converging to a point corresponding with the apex of the cone and are equally spaced, while the parallels are arcs of circles, generally concentric This class of projection is most suitable for maps of the temperate regions. TYPES OF CONICAL MAP PROJECTIONS: i. SIMPLE CONICAL WITH ONE STANDARD PARALLEL: In this projection the cone touches the globe along a chosen parallel called the standard parallel, which passes through the middle of the area. The meridians are all straight lines converging to a point, the vertex of the cone, which is beyond the North Pole above the top of the map. They are at their true distances apart along the standard parallel. The parallels are all equidistant circular arcs drawn with the vertex of the cone as the center. The distance between any two parallels represents the true distance between them on the globe. MERITS: 1. The distance between any two parallels on this projection is true. Thus, scale along all the meridians is correct. 2. The scale is correct along the standard parallel. Thus, areas lying adjacent to the standard parallel are fairly correctly represented on this projection. A long narrow strip of land running along the standard parallel in the east-west direction is shown fairly correctly on this projection. Railway, roads, narrow river valleys and the international boundaries running in the east-west direction for a long distance can be shown on this projection. 3. The Canadian pacific railway, Trans-Siberian Railway, international boundary between Canada and the USA, the Narmada Valley, etc. may be shown on this projection. The parallel running close to the railway, roads, the river valley, the international boundary, etc. shall be selected as the standard parallel. 4. The scale along the meridians is also correct. A narrow strip along a meridian is, thus, represented in a satisfactory way. It can be used for showing Chile, the Rockies, etc. 5. It is good for any extent of longitude along the standard parallel but small extent in latitude. DEMERITS: 1. The scale along the meridians is true. But it goes on increasing along the parallels away from the standard parallel. Therefore, away from the standard parallel, areas are exaggerated and their shapes distorted. 2. As it is exaggerated along the parallels except the standard one and, therefore, the projection is not equal-area. It is also evidently not orthomorphic, as the scale is not the same in all directions at any point. 3. It is suitable only for a narrow strip of land lying adjacent to the standard parallel. ii. SIMPLE CONICAL PROJECTION WITH TWO-STANDARD PARALLEL. This projection is a slight modification of the simple conical with one standard parallel. In this, instead of one, take two standard parallels, one towards the middle of the upper half and the other towards the middle of the lower half of the map. Like the simple conic with one standard parallel, all the parallels are at their true distances apart and are represented buy concentric circular arcs whose radii from the meridians. Thus all the meridians are correct to scale. MERITS:
DEMERITS: The scale being either too large or too small along the parallels other than the standard parallels, areas far away from the standard parallels are not accurately represented on this projection, therefore, for better representation, an area should be of small latitudinal extent. This projection is neither equal-area nor orthomorphic. iii. BONNE’S PROJECTION: It is a modified conical projection with one standard parallel. It was invented by Rigobert Bonne (1727-1795). A French cartographer. In construction it is very similar to the simple conical projection with one standard parallel. The central meridian is drawn straight and is divided truly, and through the points off division the parallels are drawn as concentric circles as in the simple conical, but the meridians are not straight lines joining the vertex of the cone to the points of division of the standard parallel. Instead of this al the parallels are made of the exact lengths of the corresponding parallels on the globe, and divided truly like the standard parallel. Then the meridians are formed by drawing curves through the corresponding points on each parallel. MERITS:
DEMERITS: The shapes away from the central meridians are distorted, the distortion increasing away from the central meridians. The shapes in the margins of the projection showing a large area such as Asia are much distorted. Therefore, this projection maintains shapes satisfactorily along with its equal-area property if areas are small and compact and have not large longitudinal extent. Hence, the projection is not orthomorphic and the shapes are not well preserved. This projection is ill adapted for countries having great extent in longitude. iv. POLYCONIC PROJECTION: In this projection each parallel is constructed in the same way as the chosen standard parallel in the simple conic. The meridians are drawn as in Bonne’s. The parallels are, therefore, circular arcs, true distances part along the central meridian, but diverging from one another on either side of the central meridian, as each is drawn from a different centre. The central meridian s a straight line divided truly, while the other meridians are curves, the curvature being slight near the central meridian but increasing rapidly after the first 30 degrees of longitude. MERITS:
DEMERITS: 1. The scale along the meridians increases rapidly away from the central meridian. The shapes are, therefore, distorted away from the central meridian, the distortion increasing towards the eastern and the western margins of the projection. This projection is, therefore, suitable for preparing map of only small area with little extent in longitude that is adjacent to the central meridian. 2. It is not equal-area projection as, the scale along all the meridians except the central one is incorrect. 3. It is also not orthomorphic, as the parallels and the meridians don’t cut one another at right angles and the meridian scale is enlarged more and more away from the central meridian. This means inequality of areas towards the margins of the maps. 4. The meridians except for the central meridians are curves. Therefore, adjacent map sheets when lying east and west do not fit together. v. INTERNATIONAL PROJECTION: This projection is very useful modification of the Polyconic, and is employed in one-in-a-million international map of the world, according to the decisions of the international map committee (1909). The map consist of 2,222 sheets, each covering 6 degree of longitude and 4 degree of latitude below the 60th parallel, and 12 degree of longitude and 4 degree of latitude above it up to the 88th parallel, the two sheets of the polar areas are circular, each being 4 degree in diameter. MERITS:
DEMERITS: The international map of different countries is prepared on separate sheets. All of the sheets have not the same latitudinal or longitudinal extent 3. ZENITHAL MAP PROJECTION: These are the projections made on a plane touching the globe at any suitable point. The plane is usually made to touch one of the poles or some point on the equator and in oblique cases a point intermediate between the equator and the poles. It is most suitable for showing polar areas. The zenithal or azimuthal, group of projections includes all types that are centered about a point and have a radial symmetry. ZENITHAL PERSPECTIVE PROJECTION:
This is the projection in which the surface is plane placed tangentially at a pole of the globe and the ‘viewpoint’ at the centre of the globe. It is also known as a great-circle sailing chart. Its name has been derived from the Gnomon of Sundial. MERITS:
DEMERITS: 1.Equator cannot be shown on this projection. 2. Shapes are generally distorted and areas greatly enlarge away from the centre of the projection. It is only small area in the central part of the projection that can be represented in a satisfactory way. However, it is constructed generally for the area lying between one of the poles and 30 degree parallel. 3. The scale along the meridians becomes rapidly greater with distance from the centre. The scale along the parallels is also too great. Therefore, all distances, shapes and areas are represented badly on this projection.
In this projection the surface is plane placed tangentially at a pole of the globe and the viewpoint at the other pole of the globe MERITS:
DEMERITS: Areas are enlarged away from the centre of the projection. It is only a small area in the central part of the projection that is represented in a satisfactory way. The representation of area is more satisfactory in this projection than in the Gnomonic projection.
In this projection the surface is a plane placed tangentially at a pole of the globe and the viewpoint at infinity. MERITS:
DEMERITS:
ZENITHAL NON-PERSPECTIVE MAP PROJECTIONS: i. Zenithal equidistant projection. ii. Zenithal equal-area projection. i. ZENITHAL EQUIDISTANT PROJECTION: This is a very common projection for polar areas and is very easy to draw. In the polar scale, of the net represents the pole and the parallels are drawn from it as concentric circles, at correct distances apart. The meridians are represented by straight lines drawn from the center at the required interval. MERITS: 1. The meridians are straight lines radiating from the pole and spaced correctly at true angular interval i.e., the azimuths are true in this projection. 2. Since the spacing between the parallels represents true distances, the scale along the meridians is correct. 3. This projection is commonly used for preparing maps of polar areas used for general purposes. 4. Since the scale along the meridians is correct, narrow strips running along the meridians are drawn fairly correctly. DEMERITS: 1. Shapes being greatly distorted away from the centre of the projection, it is only a small area in the central part of the projection that can be represented in a satisfactory way. The area lying between the pole and 60 degree parallel is shown satisfactorily. It is neither equal-area nor orthomorphic. 2. The scale along the parallels is too large, and the error increases with distance from the centre. ii. ZENITHAL EQUAL-AREA PROJECTION In the polar-zenithal equal area projection, like the zenithal equidistant, the meridians are radiating straight lines and the parallels are concentric circles, but the distance between the parallel circles are reduced in the same proportion as the scale along the parallels is too large. The parallels are thus closer together away from the centre. MERITS: 1. The meridians are straight lines radiating from the pole. They are spaced correctly at true angular interval i.e., the azimuths are true in this projection. 2. Shapes are more and more distorted away from the centre of the projection because the scale along the meridians is too small and that along the parallels too large. The shapes are compressed along the meridians but stretched along the parallels. 3. Since it is an equal-area projection and the shapes of the countries in the central part are preserved in a fairly satisfactory way this projection is used for preparing political and distribution maps of Polar Regions. 4. It is also used for making general-purpose maps of large areas in the Northern Hemisphere. DEMERITS:
4. CONEVNTIONAL PROJECTIONS: These projections do not fall into the systems of cylindrical, conical and zenithal projections. In these projections, the parallels and the meridians are drawn arbitrarily so as to make the graticule of a projection more useful for specific purposes. They are drawn generally for showing the whole world. TYPES OF CONVENTIONAL PROJECTIONS: Following are the conventional projections:
This is a particular case ofBonne’s projection where equator is taken as the standard parallel. Therefore, all its properties are also similar. The equator and the central meridians are straight lines at right angles to each other and divided truly. The parallels are also straight lines parallel to the equator and are divided truly for the meridians intervals. The meridians are curves drawn through the corresponding points on the several parallels. Its merits and demerits are almost same as that of Mollweide’s projection. MERITS: 1. This projection is equal area as in each graticule the limiting parallel are true to scale and the perpendicular distance between them is correct 2. As the meridians are curves of Sines (or cosines) the projection is also called the sinusoidal. It is very important for Africa and South America, and is frequently used for them. If these countries are placed in the corner of the projection, the continent is extremely well shown, with little distortion of scale or shape. DEMERITS:
This projection is invented by Karl B. Mollweide in 1805. It is also known as homolographic projection. “Homolographic” is a word often used to mean “equal-area”, a property that this projection possesses. One hemisphere is outlined by a circle; the other hemisphere is divided into two parts and added with an elliptical outline to either side of the circle. All other meridians, except the straight central meridian, are halves of ellipses. The equator is twice as long as the central meridian, which is also true on a globe. MERITS:
DEMERITS:
Both the Mollweide’s and Sanson-Flamsteed’s projections can be interrupted to avoid distortion—the chief drawback of these projections. Breaks can be made in those parts which are not material, e.g. in the case of continents, the breaks could occur at the pecans. The idea is to show only the best part of the projection with each land mass having its own central meridians; hence the word “recentred” means. In other words, they may be regarded as Mollweide’s or Sanson-Flamsteed’s projection with several centered meridians. MERITS: 1. The projection is equal-area, hence is useful for statistical distribution. 2. The shapes are realistic and fairly orthomorphic as only the best part of the projection is used. DEMERITS: 1. World relations cannot be shown because of the discontinuity of the oceans. 2. It is not true-bearing. 3. The awkward shape is not very pleasing.
Thisis a purely conventional or arbitrary projection which has no special properties except that it is very easy to make. It is often used in atlases for the map of the world in hemispheres. A circle is drawn to represent each hemisphere, its horizontal diameter representing one-half of the equator and the vertical diameter the central meridian. The meridians are arcs of circles, concave to the central meridian, and spaced at equal intervals along the equator, while the parallels are arcs of circles convex to the equator and spaced at equal intervals along the central and the bounding meridians. MERITS: 1. It is used in atlases for the map pf the world in hemisphere. Mercator’s projection is used for showing the distribution of winds and ocean currents. MERCATOR’S PROJECTION: This projection named after its inventor, was devised by Gerardus Mercator, a Dutch, in 1569. The meridians on the simple cylindrical projection and the cylindrical equal-area projection don not converge towards the poles. They are equi-distant throughout these projections, i.e., the distances between the meridians increases towards the poles in these projections. Mecartor devised a mathematical formula by virtue of which he placed the parallels increasingly father apart towards the poles thereby increasing the lengths of the meridians but taking care that the increase in the lengths of the meridians was in the same proportion in which the lengths of the parallels increased. By doing so he got a true orthomorphic projection. The projection is, therefore, also called the cylindrical orthomorphic projection. In this projection, as in simple cylindrical projection, the parallels and the meridians are represented by straight lines at right angles to one another, and the meridians are spaced at equal distances. But to preserve the shapes of areas, the distance along the meridians (i.e., between the parallels) are elongated. In various latitudes in proportion to the stretching of the parallels, all of which are represented by exaggerated lengths, all being equal to the equator. In other words, at any latitude the meridians are stretched towards the poles to the same extent as they are done east and west to become parallel to one another. The scale along the meridians is increased in the same proportion as it is done along the parallels, so that it is the same north and south as it is east and west. PROPERTIES: 1. Parallels are meridians are straight lines. 2. The meridians intersect the parallels at right angles. 3. The distance between the parallels go on increasing towards the poles but the distances between the meridians remain the same. 4. All the parallels are of the same length and every one of them is equal to the length of the equator. 5. The length of the equator on this projection is equal to the length of the equator on the globe. Therefore, the scale along the equator is correct. The parallels are longer than the corresponding parallels on the globe. For example, 30º parallel, 60º parallel and 80º parallel on this projection are 1.154 times, 2.000 times and 5.758 times longer than the corresponding parallels on the globe respectively. The poles cannot be shown on this projection because exaggeration in the scales along 90º parallel and the meridians touching them in infinite. 6. The meridians are longer than the corresponding meridians on the globe. They are made longer so as to make the sale along the meridians at any point equal to the scale along the parallels at the same point. The following three examples illustrate this point: a. As the length of 1º N parallel is 1.0002 times the length of the 1º N parallel on the globe, the length of the meridians between 0º (equator) and 1º N parallel is 1.0002 times longer than the corresponding meridian on the globe. b. 20º N parallel on this projection is 1.064 times the length of the 20º N parallel on the globe. Therefore, the length of the meridians between 19º N and 20º N parallels is 1.064 times longer than the corresponding meridians on the globe. c. 80º N parallel on this projection is 5.758 times the length of the 80º N parallel on the globe. Therefore, the length of the meridian between 79º N and 80º N parallels is 5.758 times longer than the corresponding meridians on the globe. Thus, the east-west stretching is accompanied by an equal north-south stretching at every point over the entire projection. The actual amount of stretching will vary from one latitude to another. The result of this stretching is that sizes of countries in high latitude are enlarged many times more than their actual sizes. The exaggeration in the sizes of the countries within the tropics is very small. Most of Greenland lies within the polar areas and most of South America within the tropics Greenland which is about one-ninth of the size of South America appears as large as South America on Mercator’s projection. 7. The parallels and meridians also intersect each other at right angles. Therefore, the shape of countries is represented truly at very pint. Since the scale varies from parallel too parallel and is much exaggerated towards the poles, the shape of a large-sized country is distorted; it is larger on the pole ward side and relatively small on the equator ward side. Therefore, shapes of small areas are preserved on this projection but of large countries distorted. 8. At a point, the scale along the meridians is equal to the scale along the parallel. The projection is therefore, orthomorphic. 9. A straight line drawn on this projection makes the same angle with the meridians. A straight line drawn on this projection is, therefore, a line of constant bearing. Such a line is called a loxodrome or a rhumb-line. Thus, compass directions are shown by straight lines and correctly maintained in this projection. Owing to this property, Mercator’s projection is of great value for navigational purposes both on the sea and in the air. LIMITATIONS: 5. The scale along the parallels and the meridians increases rapidly towards the poles. There being a great exaggeration of scale along the parallels and the meridians in high latitudes, the sizes of the countries on this projection are very large in the polar areas. For this reason, the polar areas cannot be shown satisfactorily on this projection. 6. Poles cannot be shown on this projection because the exaggeration in the scales along the 90º parallel and the meridians touching them is infinite. USES: 1. This projection is commonly used for navigational purposes both on the sea and the air. The distance along a rhumb-line between any two points is greater than the distance along the great circle between the same two points, on the earth. A rhumb-line on this projection is a straight line but a great circle running more or less in the east-west direction is a curved line. A great circle bends towards the poles—northwards in the northern hemisphere and southwards in the southern hemisphere. A rhumb-line and a great circle, however, run together as a straight line along the equator and the meridians on this projection. The mariner gets his direction by the rhumb-line but tries to remain as near the great circle as possible to follow the shortest route. Lines indicating the great circles are marked on the maps (drawn on this projection) with the help pf Gnomonic projection. He breaks up the great circle into a number of sections and joins the points of divisions (on the great circles) by lines which serve as various legs of the rhumb-line. The mariner follows the first leg until he reaches the great circle. He then changes his bearing to follow the next leg of the rhumb-line. Thus, he goes on changing his bearings till he reaches his destination. 2. Ocean currents, wind directions and pressure systems are shown on this projection as the directions are maintained truly on this projection. 3. Maps of tropical countries are shown on this projection when they are to be used for general purposes. The reason is that exaggeration in the size of an area is small within the tropics and the shapes of the countries are preserved without much distortion.
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