Acid rain may have been an environmental cause célèbre in the 1980s, after scientists “observed the increase in acidity of some lakes and streams” caused by pollutants, but, decades later, it’s still a problem. The steps Congress has taken to monitor and minimize the effects of acid rain have done a lot to improve the situation. But, says NPR, acid rain is having some surprising effects on the nation’s waterways.
Rather than getting more acidic, rivers are now getting more basic—though acid rain, says NPR, is still to blame.
Acid rain is largely behind the phenomenon, the scientists say. It’s been eating away chunks of rock, especially limestone rock, and the runoff produces carbonates that flow into rivers. “We’re basically dissolving the surface of the Earth,” says Kaushal. “It’s ending up in our water. It’s like rivers on Rolaids. There’s a natural antacid in these watersheds.”
Like widespread acidification in the ocean, the effects of changing the acidic balance of a river will likely have effects on the things that live there, even if they’re not obvious.
Yale ecologist Peter Raymond, says NPR, “says it’s not clear what kind of damage all this is doing, though a number of freshwater organisms are likely to be affected. “Some will be winners, and some will be losers,” Raymond says.
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