Vast areas of natural habitats are destroyed in order to provide room for industrialised, intensive agriculture using single-crop techniques, thus depriving local fauna and flora of their "home". These techniques use selected sub-species of crops, which carry features that will maximise profits, such as fast growth, large fruit etc. Compared to natural populations of the crop, these selected populations are reduced in their genetic diversity. However, the more uniform the genetic composition of individuals of a certain species, the more vulnerable the population is to attacks by viruses, insects and fungi. This artificially increased vulnerability in turn causes an enhancement of pesticide application. Pesticides being major pollutants that decompose very slowly, also affect surrounding areas in a destructtive manner.
In ancient agricultural techniques, genetically distinct crop varieties were always planted together so as to form hedgerows in order to reduce possible crop losses. This approach is much more benficial in the long run.