KNOXVILLE, Tenn. (AP) -- Take care of that little backyard stream. You could reap the benefits next time you draw some water from the tap or go for a swim at the beach.
A new article in the science journal Nature describes the critical role small streams play in removing nitrogen pollution caused by fertilizers, farm animal waste, septic tanks and fossil fuels.
Lead author Patrick Mulholland of the Oak Ridge National Laboratory says the study found fungi, algae and bacteria in streams can naturally absorb or remove most nitrogen pollution.
But when nitrogen levels become too high, the streams can become overwhelmed and the pollution flows downstream where it fouls lakes and the ocean.
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