Plants may lose their carbon-capturing prowess as temperatures rise

Normally, plants are a major source serving as "carbon sinks". But recent studies suggest that with a rise in temperature,plants are losing this capability.


Warming causes dead plants to decompose more quickly, which releases carbon dioxide. But decomposition also releases ammonium—essentially fertilizer—into the soil, allowing trees to grow faster and store more carbon.

To find out which process wins out, ecologist Jerry Melillo of the Marine Biological Laboratory in Woods Hole, Massachusetts, tracked two 10,000-square-foot plots of deciduous forest for seven years. On one plot, he installed underground cables to warm the soil by 9 degrees Fahrenheit. He found that the hotter soil, rife with decaying plants, released significantly more carbon than did its cooler counterpart. That carbon burst was short-lived, however. As ammonium levels in the heated soil increased, trees grew faster and absorbed more carbon. By the study’s end, trees on the warm plot were sequestering carbon at the same rate the soil was pumping it out.


Source of Info: Discover Magazine