This study assessed the environmental impacts of using winter cereal rye cover crops as a climate change adaptation strategy in corn-soybean rotations across four experimental sites. Models were used to predict greenhouse gas emissions, soil erosion, and nitrate leaching under current and future climate scenarios with and without cover crops. Results showed that cover crops reduced nitrous oxide emissions, soil loss, and nitrate loss without affecting corn yields. However, cover crops required additional energy inputs for establishment and termination. The effectiveness of cover crops varied by location depending on climate and soil conditions. Overall, cover crops were found to mitigate many negative environmental impacts of climate change in corn systems.

1. This research is part of a regional collaborative project supported by the USDA-NIFA,
Award No. 2011-68002-30190 “Cropping Systems Coordinated Agricultural Project (CAP):
Climate Change, Mitigation, and Adaptation in Corn-based Cropping Systems”
sustainablecorn.org
Model based evaluation of using cover crops as a
climate change adaptation strategy
Lei Gu, Robert Anex
Department of Biological Systems Engineering, University of Wisconsin-Madison
INTRODUCTION
Future climate is expected to exhibit increased
temperature, precipitation and high frequency of
extreme events with negative impacts on
agricultural productivity and environmental
quality. However, impacts can be reduced
through adaptation strategies like winter cover
crops.
We assess the environmental trade-offs of using
a cover crop as a climate change adaptation
strategy in different geographical locations. We
studied a no-till corn-soybean rotation with and
without cover crops at four experimental sites.
Winter cereal rye was planted immediately after
both corn and soybean harvest and terminated
two weeks before the planting of the main crop
without removing any residue. Impacts analyzed
include: crop yield, energy balance, trace gas
fluxes, nutrient loss, and soil erosion.
METHOD AND APPROACH
 Modeling
DAYCENT biogeochemical model, water erosion
prediction project (WEPP) and root zone water quality
model (RZWQM) are employed to predict GHG
emissions, soil erosion and nitrate leaching to the
environment.
Climate scenarios
Current climate: historic data from 1995 – 2014.
Future climate: 5 climate models simulating the IPCC
A1B scenario from 2041-2060.
 Experimental Sites
RESULTS AND DISCUSSION
Corn yield
Energy consumption
N2O emissions (Cover crop practice reduces N2O fluxes)
CONCLUSIONS
• Winter cereal rye cover crop can provide multiple environmental
benefits without affecting corn yield.
• Cover crop practice requires additional field operation and farming
inputs, which cost approximately 2337 - 5278 MJ/ha of energy.
• Including winter cover crops in corn-soybean system reduces soil loss,
nitrate-N loss and trace gas emissions under current climate and future
climate, but the effectiveness of cover crops varies from site to site
depending on local climate, soil conditions and crop productivities.
• The use of rye cover is predicted to significantly reduce the impacts of
climate change on the environmental outcomes.
Nitrate-N loss (Cover crop practice reduces NO3-N loss)
Soil erosion (Cover crop practice reduces soil loss)
0
5000
10000
15000
20000
25000
Energyconsumption(MJ/ha)
Cover Crop Seeds
Herbicide
Transport of ag inputs
Diesel
Farm machinery
Inputs packaging
Labor transportation
Custom work
Natural Gas
Electricity
LPG
Gasoline
Lubricant
Corn Seeds
N Fertilizer
Treatment and
climate scenario
Treatment and
climate scenario
Treatment and
climate scenario
Treatment and
climate scenario
Cover crop practice
doesn’t show
significant impact on
corn yield, but was
not able to counteract
the yield decline due
to climate change