Chapter 3: Agro-Ecological System
3.1 CLIMATE .WATER,SOIL AND HUMAN RESOURCES
Agricultural food production (crops,livestock and aquaculture) is strongly dependent on fertile soil and adequate water. it also requires suitable climatic conditions particulary temperature which is important for optimum production.without these conditions,farming activities are made difficult or
productivity is affected or may even become impossible.
Tropics
This region lies between the tropic of Capricorn in the south of the hemisphere. Between the two,lies the equator.
based on the amount of rainfall and temperature,the tropics can be further subdivided into super humid,humid and dry zoness. the humid and super humid zones are characterized by very high average daily ambient temperature and heavy rainfall that makes this region typically hot and humid throughout the year. the therefore favours abundant growth of vegetation (plants) throughout the year, the drier tropical zone may have lesser rainfall,but still favours growth of vegetation throughout the year.
Many agriculture activities are made possible with readily available water and suitable temperature. crops grown in large scales in the humid tropics include rubber,oil palm,cocoa,coconut and sugarcane.
Temperate
This climate is neither too warm nor too cold and wet not too dry. the weather,although not extreme is very changeable. four seasons can be identfied,a warm summer,a cool winter,and mild spring and autumn in between.
Typically,crops are usually planted in spring and harvested in summer like maize and wheat. however,with the advancement of science and technology in agriculture,many types of vegetable and flowers are grown continuously even during the cold winter season under controlled environment such as under shelter (glass-houses) making the vegetables and flowers available for consumers throughout the year.
in livestock farming the temperature and humidity in the tropical countries easily stress these animals. large cattle reared for milk and beef performed best in the temperature region.
Tundra
Tundra region is characterized by very low temperature and short growing season with little water and sunshine, there are three types of tundra,namely arctic,antartic and alpine.
The dominant vegetation is grasses,mosses and lichens. crops can hardly be grown. farming of crops and livestock are however possible,but in restricted enclosures with adequate water supply.
Deserts
These are landscape forms taht receive very little precipitation of less than 250 mm annually. the usually have an extreme diurnal temperature range very high in the day and extremely low at the night. vegetation is exceedingly scarce and the plants are xerophytic type. agriculture is made possible with sufficient irrigation for the supply of water.
Agricultural food production (crops,livestock and aquaculture) is strongly dependent on fertile soil and adequate water. it also requires suitable climatic conditions particulary temperature which is important for optimum production.without these conditions,farming activities are made difficult or
productivity is affected or may even become impossible.
Tropics
This region lies between the tropic of Capricorn in the south of the hemisphere. Between the two,lies the equator.
based on the amount of rainfall and temperature,the tropics can be further subdivided into super humid,humid and dry zoness. the humid and super humid zones are characterized by very high average daily ambient temperature and heavy rainfall that makes this region typically hot and humid throughout the year. the therefore favours abundant growth of vegetation (plants) throughout the year, the drier tropical zone may have lesser rainfall,but still favours growth of vegetation throughout the year.
Many agriculture activities are made possible with readily available water and suitable temperature. crops grown in large scales in the humid tropics include rubber,oil palm,cocoa,coconut and sugarcane.
Temperate
This climate is neither too warm nor too cold and wet not too dry. the weather,although not extreme is very changeable. four seasons can be identfied,a warm summer,a cool winter,and mild spring and autumn in between.
Typically,crops are usually planted in spring and harvested in summer like maize and wheat. however,with the advancement of science and technology in agriculture,many types of vegetable and flowers are grown continuously even during the cold winter season under controlled environment such as under shelter (glass-houses) making the vegetables and flowers available for consumers throughout the year.
in livestock farming the temperature and humidity in the tropical countries easily stress these animals. large cattle reared for milk and beef performed best in the temperature region.
Tundra
Tundra region is characterized by very low temperature and short growing season with little water and sunshine, there are three types of tundra,namely arctic,antartic and alpine.
The dominant vegetation is grasses,mosses and lichens. crops can hardly be grown. farming of crops and livestock are however possible,but in restricted enclosures with adequate water supply.
Deserts
These are landscape forms taht receive very little precipitation of less than 250 mm annually. the usually have an extreme diurnal temperature range very high in the day and extremely low at the night. vegetation is exceedingly scarce and the plants are xerophytic type. agriculture is made possible with sufficient irrigation for the supply of water.
WATER
Agriculture activity needs regular supply of clean water,either rain fed ( rain water) or irrigated. water is required for need germination,root development and subsequent growth.
it must be noted taht the earliest civiliszation started along the river banks like the Nile valley in Egypt and Tigris-Euphrates in Mesopotamia (present day iraq).Malaysia ,agro-ecological zones are partially based on the availability of water taht actually dictates the crops type suitably grown in the area. for example,southern penisular Malaysia has an average annual rainfall n excess of 3000 mm which makes the region most suitable for oil palm cultivation.in conttrast the kedah-perlis region receives < 2000 mm which makes it less suitable for oil palm but more suitable for rubber and mangoes.
SOIL
Soil is an important agriculture resource.from soil,plants obtain water and nutrients which ultimately are returned to the soil as indicated diagrammaticaly and briefly in the nutrient cycle.
Rain water falls to the ground is soaked up by the soil.nutrient elements which are diddolved in the water are taken up by plants.water moves from the roots the distributed throughout the plants.and is then lost through the process of evapotranspiration.as the plants grows some parts like the leaves become senescent and drop to the ground and become part of the soil as humus and organic matter. as these part decompose,nutrients are released back into the soil to be available again thus completing the nutrient cycle.
HUMAN RESOURCE
Agricultural production requires human resources with knowlegde and skills at different levels. this is particularly true in today's agriculture where there is strong science and technology based knowledge being applied in the farming practices.
Agriculture needs many scientists who conduct research from production level o processing and marketing. we also need teaching institutions of agriculture to produce graduates in numerous fields of specialization such as those associated with the environment,soils,plants,and animals. we also need supporting specialists such as extension specailist to pass the knowlwdgw to the operators in the fields,marketing specialists and the economists.
ENVIRONMENT
Global Agro-Ecological Zones
it is common knowledge that not all agricultural commodities can be produced in all regions in the world;
a) tundra (very cold climate,low biotic diversity,simple vegetation of mosses grasess,dwarf trees)
b) grasslands (the Amercan Prairies,Russian Steppes,African Savannah and Argentinian Pampas,low fertile land,mild climate,field crops such as soybeans,wheat,maize,and livestock.
c) deserts (very little precipitation,extreme diurnal temperature,barren land plants are xerophhytic,examples of the deserts are sahara (africa),kalahari (africa).,gobi (china) and arabia
d)tropics (rain and sunshine all year round,rainforest,rubber,oil palm,cocoa,coconut and breadfruit)
IMPACT OF CLIMATE CHANGES
IMPACT OF POLLUTION
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