Convergence of agricultural intensification and climate change in the Midwestern United States: implications for soil and water conservation
J. L. Hatfield A , R. M. Cruse B and M. D. Tomer A C
+ Author Affiliations
- Author Affiliations
A United States Department of Agriculture, Agricultural Research Service, National Laboratory for Agriculture and Environment, Ames, IA 50011, USA.
B Iowa State University, Department of Agronomy, Ames, IA 50011, USA.
C Corresponding author. Email: mark.tomer@ars.usda.gov
Marine and Freshwater Research 64(5) 423-435 https://doi.org/10.1071/MF12164
Submitted: 23 June 2012 Accepted: 7 January 2013 Published: 3 May 2013
Journal Compilation © CSIRO Publishing 2013 Open Access CC BY-NC-ND
Abstract
Society faces substantial challenges to expand food production while adapting to climatic changes and ensuring ecosystem services are maintained. A convergence of these issues is occurring in the Midwestern United States, i.e. the ‘cornbelt’ region that provides substantial grain supplies to world markets but is also well known for its contribution to hypoxic conditions in the Gulf of Mexico due to agricultural nutrient losses. This review examines anticipated trends in climate and possible consequences for grain production and soil resource management in this region. The historic climate of this region has been ideal for large-scale agriculture, and its soils are among the world’s most productive. Yet under current trends, degradation of the soil resource threatens our capacity to ensure a stable food supply and a clean environment in the face of a changing climate. A set of strategies and practices can be implemented to meet these challenges by maintaining and improving hydrologic and plant-growth functions of soil, which will improve outcomes for aquatic ecosystems and for the agricultural sector. Soil management ensures our long-term capacity to provide a reliable food supply, and mitigates pressures to expand agricultural practices into marginal croplands that would lead to further environmental degradation.
Additional keywords: agroecosystems, food security, hypoxia, soil management.
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