Exploring ‘Cover Crop/ Climate’ Connections
Michigan State University researchers are studying the impact of “cover crop” use on everything from row crops to orchards and carrots to Christmas trees.
Planted to provide a protective green blanket when land is normally barren or lifeless, cover crops help create a year-round habitat providing food and shelter for wildlife as well as beneficial organisms in the ground. Cover crops help retain the nutrients from the previous crop and pass them on to the next. They also take in carbon dioxide from the atmosphere and release clean oxygen in exchange.
Cover crops and climate
In addition to soil fertility studies, Alexandra “Sasha” Kravchenko, professor in the MSU Department of Plant, Soil and Microbial Sciences (PSMS), is looking at ways that cover crops can help mitigate climate variability as part of a large-scale project, Climate and Corn-based Cropping Systems Coordinated Agricultural Project (CSCAP), funded by the USDA.
“To me, there seems to be the beginning of a comeback occurring in soil research,” she said. “We came to the realization that while what we do know about soils might be good enough for business as usual, it’s not enough to anticipate future impacts of variable climate.”
CSCAP encompasses 140 researchers at 10 Midwestern universities, including fellow MSU researchers Bruno Basso from the Department of Geological Sciences and Andrey Guber from the Department of Plant, Soil and Microbial Sciences who work on modeling; Martin Chilvers from the Department of Plant, Soil and Microbial Sciences working on the integrated pest management portion; and Marilyn Thelen from MSU Extension on the outreach component.
The group is focused on understanding the mechanisms by which cover crops increase soil carbon sequestration, how they impact greenhouse gas emissions and how they influence corn yields and soil nitrates.
Positive changes in soil health
Kravchenko is conducting trials at two experimental sites, one in Mason, Mich., and the other at Kellogg Biological Station. Each site has diverse topography, allowing researchers to examine cover crop performance in a real-life terrain. This past spring researchers began collecting soil samples from the experimental fields and will begin comparing it to data from 2011 when the project started.
“We’re seeing some positive changes in soil organic matter when cover crops are used,” she said. “But we’re not quite there yet. Cover crops are a tool but they don’t work overnight. It takes several years to produce the noticeable, beneficial effects.”
– excerpted from “Cropping Up,” Futures (Spring/Summer 2015) by Holly Whetstone
Photo: (From left) MSU Department of Plant, Soil and Microbial Sciences professor Alexandra “Sasha” Kravchenko and graduate student Jessica Fry examine data from a MSU cover crop testing site located in Mason, Mich. Kravchenko is focused on explaining how cover crops increase carbon sequestration among several issues.