Heat-Related Nitrogen Loss Endangers Desert Plant Life, Study Finds

The loss of nitrogen from arid soils caused by a warming climate could make the world’s deserts even more inhospitable to plant life, according to a new study by researchers at Cornell University. Using highly sophisticated instrumentation that measures nitrogen in the parts per trillion — and using dark covers to remove sunlight as a factor in the measurements — researchers found that nitrogen loss in the arid soils of the Mojave Desert of the southwestern United States increased rapidly as temperatures reached 40 to 50 degrees C (100 to 120 degrees F). Noting that nitrogen is second only to water as a constraint on plant life in arid ecosystems, the researchers said a warming climate, as well as shifting precipitation patterns, could make soil arid ecosystems even more infertile. “We’re on a trajectory where plant life in arid ecosystems could cease to do well,” said Carmody McCalley, lead author of the study, which will be published in the journal Science. With deserts accounting for 35 to 40 percent of the planet’s surface, and future human developments likely to be targeted in arid and semi-arid regions, the researchers urged that climate models be altered to factor in these findings.