Farming in LEDC's and MEDC's Can Have a Negative Impact on Soils
Soils are a vital resource to humans as without them there would be no
means to feed the world's growing population. However, the global
demographic changes are putting increasing pressure on farmers to grow
more and in response to this, more land is being used for farming and
the methods used to farm the land are not always beneficial to the
soil in the long term. Agricultural activities are the one of the main
causes of soil degradation.
In both the MEDW and LEDW farming techniques have changed. In Britain,
the most drastic change was in the 18th century when the Agricultural
Revolution saw the manorial system and open field cultivation in
strips replaced. Instead, large scale farming in consolidated units
was introduced, along with the extension of arable farming, intensive
livestock farming and new agricultural techniques such as crop
rotation as well as new crops such as potatoes and improved grasses.
The aim of these changes was to increase agricultural production and
over the following years more technological advances allowed output to
be increased and higher yields to be achieved. In the LEDW change is
relatively slow to happen as a result of the slow development of a
country and a lack of money to effect the changes. However, in the
1960's the Green Revolution allowed developing countries to increase
their output with high yielding varieties of crops such as IR8.
The increased use of inorganic fertilizers is having a negative impact
on the soils, though it is the main reason for increased productivity.
When farmers first used these fertilisers they used excessive amounts
which could not all be taken up by the plants. This resulted in the
dissolved fertiliser being washed into rivers and streams, polluting
the water. It also leads to a reduction in the organic matter in the
soils and therefore fertility as the nitrogen in the soil encourages
leaching of nutrients such as potassium. There is also reduced
biodiversity in places like the Netherlands where some grass species
cannot tolerate the levels of nitrogen. In the Netherlands they are
converting species rich heathlands into species poor grasslands that
can tolerate the nitrogen present.
Organic farming has recently become the 'fashionable' thing to do but
it has had a good impact on soil quality. It is a sustainable method
of farming, using no chemicals and maintaining agricultural diversity.
Organic farmers use crop rotation to help the soil structure and use
biological rather than chemical pest control. The soil nutrients are
replenished by legumes and organic manure and a minimum use of heavy
machinery means the soil is not compacted and allows free drainage.
In the past, agriculture had been very labour intensive but