soil runoff from crops

Soil runoff can carry harmful pesticides to the water system, harming the environment.

Agriculture and ecology form a tenuous balancing act. We need agriculture to grow food, but we also need to maintain ecosystems and not let farming ruin them. One significant problem is soil runoff near the beginning of the growing season. In the United States, for example, heavy spring rains erode soil, which finds its way into streams and rivers, and eventually finds its way to the ocean.

Soil, by itself, isn’t the problem–but rather the pesticides and fertilizer that is contained in the soil when it comes from crop fields. Those chemicals can cause a wide variety of problems, as they are toxic to many animals and can damage ecosystems, commercial fishing, and, as a result, tourism.

A common way to prevent runoff is to plant trees along streams and rivers, which do a much better job of holding onto soil and preventing it from getting into the water system. But planting trees close to crops tends to reduce crop yields. Trees that grow too high can block sunlight from reaching crops during part of the day, which reduces growth. Trees also tend to win the competition for nutrients in soil, outcompeting neighboring crops and leading to reduced crop yields.

According to researchers from the University of Missouri, there is a relatively simple way around the problem: barriers. They’ve found through years of study that having a barrier between the trees and crops can make all the difference. This can be simply an open space, but it is best if that space, the width depending on tree height, consists of natural vegetation like local grasses. This can help reduce runoff as well, and doesn’t compete much with the trees. Planting soy beans can also help, as they aren’t impacted by growing close to trees.

Instead of turning to chemicals to boost growth, the more natural ways we can find to improve the agricultural and ecological balance, the better. This is a relatively simple and ecologically sound way to deal with the problems of runoff and reduced crop yield.