Home >> Science & Nature >> Nature

Bad Effects of Plowing Up the Land

Erosion is the outcome of a variety of natural processes, such as wind and rain. Since the industrial revolution, however, soil erosion has accelerated. Industrial farming in particular has led to topsoil degradation at a much quicker rate than can be replenished naturally. This environmental issue has global economic ramifications as the world's population increases and the land that's available for crop cultivation dwindles. As arable land decreases worldwide, a vicious cycle of overcultivation to generate more food results in even more land being exhausted of nutrients.

Importance of Soil
- Soil contains organisms like bacteria, fungi, worms and algae. Soil is crucial to plant life for both its nutritive content and its function of recycling decaying plant and animal matter back into the food chain. It takes a few hundred years for soil to form naturally from mineral weathering and decaying biomass. Several plant species require living bacteria and fungi in the soil to survive; soil ecology is a delicate balance that can be easily disrupted by pollution or overuse.
Industrial Farming
- In the United States alone, 7 tons of soil per acre is eroded each year. Plowing up acreage for agricultural use exposes vital topsoil to erosion by wind or water. While a certain amount of erosion is unavoidable, land degradation is compounded by industrial farming's use of pesticides and synthetic fertilizers. These kill natural microorganisms present in the soil, which normally would replenish lost nutrients, such as nitrogen-fixing bacteria. Single-crop farming (also called 'monoculture') alters the ecology of topsoil by stripping specific minerals from it and exhausting the soil's ability to host other plant life.
Topsoil Depletion
- As fields lie bare, wind dries and displaces loose topsoil. Intensive tilling also destroys root systems in the subsoil that fix topsoil in place. This contributes to topsoil drying out during periods of drought. When combined with wind, dust storms of loose soil systematically move over other areas, stripping more topsoil off the land surface. The Oklahoma Dust Bowl in the 1930s underwent these conditions and only recovered when drought conditions ended. Conversely, during wet weather, topsoil that has been stripped of vegetation or subsoil roots is washed away by rainfall into waterways.
Conversion of Rainforests to Agricultural Use
- The felling of rainforests to convert the land to agricultural use has severe ecological consequences. Most rainforest topsoil is of poor quality, and is only a thin layer held in place by root systems. Exploiting this topsoil to grow crops quickly exhausts the nutrients present, and leaves the soil sterile and unable to support vegetation. Either the land is abandoned, exposing it to erosion, or synthetic fertilizers are added. This can result in excess chemical runoff disrupting the surrounding ecosystems. "Slash and burn," or subsistence farming, removes trees to grow crops, but also strips away soil nutrients and causes erosion in the long term.

Nature