Agriculture comes with an enormous environmental price. It has claimed some of the most pristine habitat in the country since settlement, including native prairie and wetlands. With over two million farms in the United States, it is easy to understand how farming may affect water resources.
Agriculture, of course, is a necessity. However, modifications of some farming practices can mitigate the effects on the land. According to the U.S. Department of Agriculture 2007 Census of Agriculture, less than one-quarter of the nation’s farms and ranches use conservation methods, such as no-till.
On the positive front, over 340,000 farms had land enrolled in Conservation Reserve, Wetlands Reserve, Farmable Wetland or Conservation Reserve Enhancement programs. This figure represents nearly a 20 percent increase since 2002. The amount of land in these programs may figure prominently when dealing with pollutants such as phosphate.
The Problem with Phosphate
Phosphate is a vital nutrient for plants. In 2008, American farmers applied over four million tons onto agricultural crops. The problem with phosphate is that excess amounts in water sources can lead to algal blooms, which can lead to wide fluctuations in the amount of dissolved oxygen in the water. It can be deadly to sensitive plants and aquatic organisms.
A 2012 study by the U.S. Geological Survey analyzed the pattern of phosphate transport in ecosystems and possible mechanisms for limiting runoff into streams. Soils can only store so much phosphorus, so the risk for leaching into water resources exists.
Controlling Phosphate Pollution
The researchers found that many factors such as soil chemistry and soil type can influence how phosphate moves through the ecosystem. The data show that monitoring for basic geochemical information such as pH and dissolved phosphorus can help identify problem areas. The study also identified a potential for buffer strips can limit transport of phosphorus.
While the researchers note that more study is needed, the use of simple conservation techniques like buffer strips has great potential for implementing an effective solution easily. It also supports the practices of conservation programs like CRP, which uses these methods to protect land.
These findings are especially important as an updated version of the Farm Bill in the United States is being debated. The data underscore the need to maintain and support conservation programs to provide the necessary incentive to farmers to protect natural resources.