Agriculture and Environment: Corn (Maize)

Habitat Conversion

Corn is produced in a wide range of settings. In developed countries, corn tends to be produced on the same fields year after year or in rotation with other crops.

In these countries any expansion of corn production tends to correspond with a decline in areas used for other crops. There is little habitat conversion for the production of corn at this time, although that was very common during the last 200 years in areas like the United States.

Even where major habitat conversion took place decades or even generations ago, corn production is still changing the landscape. As machinery gets bigger, fields get bigger. This means the loss of fencerows and hedges that often were a safe haven for biodiversity. Larger machinery makes it more difficult to disengage to avoid grass-covered waterways. Tilling these areas in the past 30 years has led to increased erosion.

In developing countries corn production is gaining at the expense of other crops. Production is also becoming increasingly mechanized. In addition, however, habitat conversion for corn cultivation is also occurring. This is true of the planned colonization schemes in the greater Amazon region as well as the more generalized displacement of people in Central and South America (e.g., when labour-intensive crops such as cotton, coffee, and other crops were abandoned in favour of cattle).

Perhaps the greatest impact of corn production on natural habitats at this time is occurring in Central and Southern Africa, where corn production is expanding more rapidly than anywhere in the world (due to government subsidies) and demand still far exceeds supply.