Growing a single crop species over a large area or farm is called intensive farming or monoculture. Earlier practices of mixed cropping caused problems in crop management, like harvesting, etc. Uniformity in plant height adds beauty to our fields and makes the application of agrochemicals easy. It also saves time and energy in segregating grains in threshing.
Impacts of Monoculture on Environment
The practice of producing or growing one single crop over a wide area, again and again, is called as monoculture. There may be two definitions of monoculture: Vegetation composed of a single species, and a field composed of a single crop rather than multiple crop species. During the days of the green revolution, farmers had to practice monoculture due to its beneficial effects, like –
o Reduced plant competition for nutrients, space and solar radiation,
o Control of undesirable or unprofitable organisms,
o Reduction of costs by limitation of specialized machinery required for arable operations,
o Maximizes profit from the growing of high gross margin crops.
Despite above benefits, monoculture has many adverse impacts on agriculture as well as on environment on the whole. Some of these impacts are mentioned below-
1. In monoculture, a vast area is cleared to convert it into a big farm. For this, all the trees and bushes are to be cleared without leaving any obstruction in between. This exposes the soil to the battering action of rain, wind and water current. Extensive soil erosion follows in such an area. We have been losing about 7 million hectares of useful cropland every year due to soil erosion as per the reports of the U N and FAO (1980).
2. The monoculture provides ideal conditions for development of a vast variety of insect pests and diseases. More and more pesticides are needed for their control and eradication. Thus, a lot of money is wasted in purchasing synthetic pesticides.
3. High yielding crop varieties drive away a number of indigenous crop varieties. For example, there were about 40,000 indigenous varieties of rice before the green revolution. But, due to monoculture, most of these indigenous varieties have disappeared and only 50 of these have remained in Indian fields by now. Thus, this method of agriculture wiped away most of our indigenous genetic resources.
4. Most of the oil seeds and pulses have been neglected through monoculture as only wheat, rice and maize occupied major areas of farmlands. These crops make the soil fertile by enriching it with nitrogen. As such, farmers have to purchase more and more nitrogenous fertilizers from the markets. This results in a pressure on the national economy.
5. The cultivation of only dwarf varieties of wheat and rice created the problems of straw fodder. Thus, farmers have to invest more money in making arrangements of feed for cattle.
6. Little fallow periods are to be left in between two crops. So, it does not consume much time to recoup the lost fertility. So, more and more fertilizers have to be added, with each group. But gradually, the organic matter appears and soil is converted into a heap of sand, silt and clay, mostly deficient in nutrients.
