|Author:||Vaishali Sharda, Prasanna H. Gowda, Gary Marek, Isaya Kisekka, Chittaranjan Ray, and Pradip Adhikari|
|Book Group Author:|
There is an increasing need to strategize and plan irrigation systems under varied climatic condi-tions to support efficient irrigation practices while maintaining and improving the sustainability of groundwatersystems. This study was undertaken to simulate the growth and production of soybean [Glycine max(L.)] underdifferent irrigation scenarios. The objectives of this study were to calibrate and validate the CROPGRO-Soybeanmodel under Texas High Plains’ (THP) climatic conditions and to apply the calibrated model to simulate theimpacts of different irrigation levels and triggers on soybean production. The methodology involved combiningshort-term experimental data with long-term historical weather data (1951–2012), and use of mechanistic cropgrowth simulation algorithms to determine optimum irrigation management strategies. Irrigation was scheduledbased on five different plant extractable water levels (irrigation threshold [ITHR]) set at 20%, 35%, 50%, 65%,and 80%. The calibrated model was able to satisfactorily reproduce measured leaf area index, biomass, andevapotranspiration for soybean, indicating it can be used for investigating different strategies for irrigating soy-bean in the THP. Calculations of crop water productivity for biomass and yield along with irrigation water useefficiency indicated soybean can be irrigated at ITHR set at 50% or 65% with minimal yield loss as compared to80% ITHR, thus conserving water and contributing toward lower groundwater withdrawals.
|Journal:||Journal of the American Water Resources Association (JAWRA)|
CROPGRO-Soybean; irrigation water use efficiency; crop water productivity; deficit irrigation; irrigation strategy