‘Climate-smart soils’ may help balance the carbon budget
Here’s the scientific dirt: Soil can help reduce global warming.
While farm soil grows the world’s food and fiber, scientists are examining ways to use it to sequester carbon and mitigate greenhouse gas emissions.
“We can substantially reduce atmospheric carbon by using soil. We have the technology now to begin employing good soil practices to reduce greenhouse gas emissions,” said Johannes Lehmann, Cornell professor of soil and crop sciences, co-author of the Perspectives piece, “Climate-smart Soils,” published in Nature, April 6.
Decreasing greenhouse gas emissions, sequestering carbon and using prudent agricultural management practices that tighten the soil-nitrogen cycle can yield enhanced soil fertility, bolster crop productivity, improve soil biodiversity, and reduce erosion, runoff and water pollution. These practices also buffer crop and pasture systems against the impacts of climate change.
Currently, Earth’s atmosphere holds about 830 petagrams (1 trillion kilograms) of carbon and humans add about 10 petagrams of carbon to the atmosphere every year, because of industrial and agricultural waste, and fossil-fuel burning vehicles, according to Lehmann. Soils, however, hold about 4,800 petagrams of carbon to a depth of 2 meters, which is six times the amount of carbon dioxide currently in the atmosphere. The good news is that soils have the potential to hold even more, said the scientists.