[audio:http://wamcradio.org/EarthWise/wp-content/uploads/2012/03/EW-03-28-12-Vernal-Pools.mp3|titles=EW 03-28-12 Vernal Pools]
Each spring, after snowmelt, the landscape becomes dotted with pools of standing water. It’s easy to dismiss these wet spots as puddles, but they play a vital role in preventing flooding, protecting groundwater, and providing habitat to wildlife.
Called vernal pools, these temporary wetlands don’t contain fish. This makes them ideal breeding habitat for frogs and salamanders. Millions of eggs are laid in the pools, which become a nursery for tadpoles and larval salamanders. The calls of spring peepers are a harbinger of spring, while salamanders go about their business silently.
A network of vernal pools can capture runoff from snowmelt and rainstorms, reducing the risk of flooding. And the bacteria present in the pools, help clean the water.
One group of bacteria converts nitrate pollution to harmless nitrogen gas, which is emitted to the atmosphere.
The nitrate in runoff comes from the fertilizer we apply to our lawns and golf courses, and is linked to a number of human health problems. Ecosystem scientist Peter Groffman describes the importance of denitrification…
“There’s a drinking water limit. Water that has more than ten milligrams of nitrogen per liter in it as nitrate is considered unfit to drink, and the dominant human health concern that led to that regulation is methemoglobinemia, which is a condition of oxygen deprivation in the blood of infants.”
Wetlands are more than an obstacle to development, and vernal pools are more than transient puddles. Protecting them comes with benefits to wildlife, roadways, and water resources.
Photo, taken on April 19, 2006 using a Canon PowerShot A70, courtesy of Dan Century via Flickr.