USDA: study finds no-till farming alone not sufficient to prevent water pollution from nitrate

photo: A no-till field.

INDIANAPOLIS – A new IUPUI study funded by the U.S. Department of Agriculture answers a long-debated agricultural question: whether no-tillage alone is sufficient to prevent water pollution from nitrate. The answer is no.

Researchers in the Department of Earth Sciences in the School of Science at IUPUI conducted a meta-analysis to compare runoff and leaching of nitrate from no-till and conventional tillage agricultural fields. Surface runoff and leaching are two major transportation pathways for nitrate to reach and pollute water. Due to its mobility and water solubility, nitrate has long been recognized as a widespread water pollutant.

"What we found is that no-till is not sufficient to improve water quality," said Lixin Wang, an assistant professor and corresponding author of the paper. "In fact, we found that no-till increased nitrogen leaching." The study suggests that no-till needs to be complemented with other techniques, such as cover cropping and intercropping or rotation with perennial crops, to improve nitrate retention and water-quality benefits. After studying concentration of nitrate — nitrate amount per water volume unit — and nitrate load, or total amount of nitrate, researchers found surface runoff from no-till fields to contain a […]

Full article: USDA-funded study finds no-tillage alone not sufficient to prevent water pollution from nitrate

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