TY - JOUR
T1 - Soil water recharge in a semi-arid temperate climate of the Central U.S. Great Plains
AU - Grassini, Patricio
AU - You, Jinsheng
AU - Hubbard, Kenneth G.
AU - Cassman, Kenneth G.
N1 - Funding Information:
Support for this project comes from NOAA's High Plains Regional Climate Center and the Water, Energy and Agriculture Initiative, the latter made possible with funding from the Nebraska Corn Board, the Nebraska Soybean Board, the Agricultural Research Division at the University of Nebraska-Lincoln (UNL) and Nebraska Public Power District through the Nebraska Center for Energy Sciences Research at UNL. The senior author wishes to acknowledge financial support from the Fulbright Program for his graduate assistantship and from the Agricultural Research Division of the Institute of Agriculture and Natural Resources at UNL. We also thank the two anonymous reviewers for their detailed comments and suggestions to improve the original submission.
PY - 2010/7
Y1 - 2010/7
N2 - The amount of soil water at the beginning of the growing season has a large impact on crop yields in rainfed agriculture, especially in semi-arid regions and in years with below-average rainfall in more humid climates. Robust algorithms are needed to estimate soil water storage before planting to aid crop management decisions. The main objectives of this paper are to investigate soil water recharge during the non-growing season (October 20 to May 1) in a semi-arid, temperate ecosystem in south-central Nebraska (USA) and to evaluate empirical models to estimate soil water content at the beginning of the summer-crop growing season. A database of soil water content measurements collected over 5 years at nine locations in south-central Nebraska was used to estimate available water-holding limits in the soil profile and to determine the change in available soil water during the non-growing season. Regression analysis was performed to analyze the relationship among soil water recharge, residual soil water (i.e., soil water content at the end of the previous growing season), total precipitation, and available water-holding capacity (AWHC) in the root zone to 1.5 m. Precipitation storage efficiency (PSE) was calculated as the quotient of soil water recharge and total non-growing season precipitation. Predictive models to estimate soil water content at the beginning of summer-crop growing season were derived from these analyses. A large portion of the variation in soil water recharge was explained by residual soil water and precipitation. PSE averaged 28% across site-years; low PSE values were associated with high residual soil water and/or low AWHC. Two predictive models (linear and linear-plateau) that used residual soil water, total precipitation, and AWHC as independent variables explained 75-80% of the variation in the measured soil water content at the beginning of the summer-crop growing season. These empirical models represent a new tool to estimate soil water content by planting date of summer crops. Site-management conditions such as residue amount and its architecture, tillage system, soil texture, and terrain slope are not currently accounted for in these models and would likely improve predictive capacity.
AB - The amount of soil water at the beginning of the growing season has a large impact on crop yields in rainfed agriculture, especially in semi-arid regions and in years with below-average rainfall in more humid climates. Robust algorithms are needed to estimate soil water storage before planting to aid crop management decisions. The main objectives of this paper are to investigate soil water recharge during the non-growing season (October 20 to May 1) in a semi-arid, temperate ecosystem in south-central Nebraska (USA) and to evaluate empirical models to estimate soil water content at the beginning of the summer-crop growing season. A database of soil water content measurements collected over 5 years at nine locations in south-central Nebraska was used to estimate available water-holding limits in the soil profile and to determine the change in available soil water during the non-growing season. Regression analysis was performed to analyze the relationship among soil water recharge, residual soil water (i.e., soil water content at the end of the previous growing season), total precipitation, and available water-holding capacity (AWHC) in the root zone to 1.5 m. Precipitation storage efficiency (PSE) was calculated as the quotient of soil water recharge and total non-growing season precipitation. Predictive models to estimate soil water content at the beginning of summer-crop growing season were derived from these analyses. A large portion of the variation in soil water recharge was explained by residual soil water and precipitation. PSE averaged 28% across site-years; low PSE values were associated with high residual soil water and/or low AWHC. Two predictive models (linear and linear-plateau) that used residual soil water, total precipitation, and AWHC as independent variables explained 75-80% of the variation in the measured soil water content at the beginning of the summer-crop growing season. These empirical models represent a new tool to estimate soil water content by planting date of summer crops. Site-management conditions such as residue amount and its architecture, tillage system, soil texture, and terrain slope are not currently accounted for in these models and would likely improve predictive capacity.
KW - Non-growing season
KW - Precipitation
KW - Precipitation storage efficiency
KW - Soil water recharge
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U2 - 10.1016/j.agwat.2010.02.019
DO - 10.1016/j.agwat.2010.02.019
M3 - Article
AN - SCOPUS:77950520381
SN - 0378-3774
VL - 97
SP - 1063
EP - 1069
JO - Agricultural Water Management
JF - Agricultural Water Management
IS - 7
ER -