Journal article
Simulating county-level crop yields in the Conterminous United States using the Community Land Model: The effects of optimizing irrigation and fertilization
G Leng, X Zhang, M Huang, Q Yang, R Rafique, GR Asrar, L Ruby Leung
Journal of Advances in Modeling Earth Systems | AMER GEOPHYSICAL UNION | Published : 2016
DOI: 10.1002/2016MS000645
Abstract
In this study, we applied version 4.5 of the Community Land Model (CLM) at a 0.125° resolution to provide the first county-scale model validation for simulating crop yields over the Conterminous United States (CONUS). Large bias was found in simulating crop yields against U.S. Department of Agriculture (USDA) survey data, with county-level root-mean-square error (RMSE) of 42% and 38% for simulated US mean corn and soybean yields, respectively. We then synthesized crop yield, irrigation and fertilization data sets from USDA and U.S. Geological Survey (USGS) to constrain model simulations. Compared with fertilization, irrigation has limited effects on crop yields with improvements limited to i..
View full abstractGrants
Awarded by NASA Terrestrial Ecology Program
Awarded by U.S. Department of Energy
Funding Acknowledgements
We thank the editor Dr. Paul Dirmeyer, the anonymous associate editor and two anonymous reviewers for their constructive comments and suggestions that helped to improve the quality of this paper. This study was carried out with support from the Integrated Assessment Research program through the Integrated Multi-sector, Multi-scale Modeling (IM<SUP>3</SUP>) Scientific Focus Area (SFA) sponsored by the Biological and Environmental Research Division of Office of Science, U.S. Department of Energy. The work related to the comparison between surveyed and modeled crop yields are also partially funded by the DOE Great Lakes Bioenergy Research Center and NASA Terrestrial Ecology Program (NNH12AU03I), and a Laboratory Directed Research and Development Project by the Pacific Northwest National Laboratory (PNNL). PNNL is operated by Battelle Memorial Institute for the U.S. Department of Energy under contract DE-AC05-76RLO1830. Data set for configuring the model is available from the corresponding author upon request. The gridded crop area data are downloaded from ftp://ftp.rz.uni-frankfurt.de/pub/uni-frankfurt/physische_geographie/hydrologie/public/data/MIRCA2000/harvested_area_grids. The USGS irrigation amounts are downloaded from http://water.usgs.gov/watuse/. The USDA fertilizer use data are downloaded from http://www.ers.usda.gov/dataproducts/fertilizer-use-and-price.aspx. The USDA crop yields data are downloaded from http://www.nass.usda.gov/Quick_Stats/. Field data from the Kellogg Biological Station (KBS) are downloaded from http://lter.kbs.msu.edu/.