S-Cool Revision Summary
S-Cool Revision Summary
Classification
|
Term |
Definition |
|
Intensive |
High input or yields for given area of land |
|
Extensive |
Low inputs or yields for given area of land |
|
Commercial |
Crops are cultivated and animals reared to be sold. |
|
Subsistence |
Cultivating crops or rearing animals for consumption by the farmer and his family. |
|
Arable |
The cultivating of crops |
|
Pastoral |
The rearing of animals |
|
Mixed |
A combination of arable and pastoral |
Subsistence farming
The aim of subsistence farming is to cultivate crops or rear animals for consumption by the farmer and his family.
It is typical of agriculture in less economically developed countries.
Agribusiness
Agribusiness uses modern technologies to increase crop yields. Farmers produce cash crops for food or as a raw material in manufacturing.
Farms are generally very large with high capital investment. This means that farms can benefit from economies of scale.
Collectives
Collectives refer to the situation where a farm is run by several people or whole communities who share in the management, work and profits. The farms are usually government owned but the collective is given a permanent lease.
These are a feature of agriculture in communist states such as China and North Korea.
You will need to be able to discuss factors that affect the global distribution of agricultural systems. The reasons are outlined below:
Physical
Climate
Climatic factors include...
Temperature - extremes prevent agricultural use.
Rainfall - reliability and distribution throughout the year are more significant that annual amount
Wind - can physically destroy a crop
Soil - certain soils favour certain plants
Slope - steep slopes encourage run-off and soil erosion rather than infiltration. They will only be used if absolutely necessary
Human
Human factors include...
Land tenure - owner occupiers have the greatest incentives to increase yields
Market - farmers will grow crops that are profitable
Transport - see Von Thunen
Capital - will determine the level of technology a farmer can utilise
Technology - new technology can increase yields and affect the landscape
Government - policies will influence what systems a farmer uses or crops he grows
Von Thunen - provides us with an explanation of land-use. He uses locational rent to explain how land use will change as you move away from an urban area. As you move away so intensity will decrease as a consequence of inhibitive transport costs.
Changes in Farming
One significant change in recent years has been the movement to organic farming.
We can define organic farming, as:
"Farming that does not use industrially produced chemicals as pesticide, herbicide, fertiliser. Nor does it use drugs to increase the size/ yield of its livestock."
Organic farming has increased for two reasons:
-
It has been led by farmers with smallholdings who feel a deep commitment to the environment.
-
It is also consumer led as people are concerned about the chemical content and safety of many foods. The BSE crisis has furthered the demand for organically grown food.
Impact of agriculture on the physical environment
Loss of natural habitat
Farming can lead to the loss of natural habitats.
The total amount of hedgerow removed or damaged is 6 x the circumference of the globe.
Reasons for loss of hedgerow?
Increased mechanisation in agriculture encourages farmers to increase the size of their fields. This they do by removing hedgerows.
The following table outlines the arguments for and against hedgerows:
|
For hedgerow preservation |
Against hedgerow preservation |
|
They are a unique and balanced ecosystem. They may harbour pests but they also harbour the predator of that pest |
They can provide homes for pests and weeds which damage crops |
|
They contain a vast array of wildlife including many endangered species and they increase bio-diversity |
They are a hindrance to the large machinery that makes farming efficient and reduces food prices to the consumer |
|
Evidence to suggest that they act as a natural barrier to the spread of disease. They also act as wind breaks that protect crops and reduce soil erosion |
They need to be maintained which is costly |
|
They are a part of our rural heritage |
They were planted by farmers in the first place so are not traditional |
Ps. 39 out of 42 hedgerow birds are beneficial to farmers.
Farmers to increase the available land and reduce the potential disease from stagnant water have drained ponds. This removes another habitat for birds, fish, insects and plants.
The soil itself is an ecosystem and inappropriate farming techniques can lead to soil erosion. Overgrazing, over cultivation and deforestation all damage the soil making it more prone to the effect of erosion.
In the developing world the pressure growing populations and foreign debt repayments has seen the removal of natural vegetation cover to make way for cash cropping.
Use of chemicals
As farmers attempt to increase yields so they can increase their use of fertiliser, pesticides or slurry. Each of these can have potentially damaging effects on the environment.
Eutrophication
Fertiliser and slurry are used to increase the nitrogen content of the soil so encouraging healthy plant growth. If too much is used then it can be leached into underground water supplies and rivers. This is called eutrophication. It then encourages algal and plant growth in the river or lake. These multiply rapidly then die off as oxygen is used up. Bacteria then multiply as the plants decompose. These bacteria use up any remaining oxygen and produce toxic bi-products. The lack of oxygen and increased toxicity kill fish life. This can encourage even more harmful bacteria.
Pesticides
Another problem. In the developing world there are countless examples of pesticide poisoning. In the UK the "Mammal Society" claim there are 24 species in danger of extinction as a consequence of pesticide use.
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