Institute: North Dakota
Year Established: 2018 Start Date: 2018-03-01 End Date: 2019-02-28
Total Federal Funds: $6,000 Total Non-Federal Funds: $12,000
Principal Investigators: Xinhua Jia
Abstract: It is crucial to accurately measure the actual evapotranspiration (ETc) from dominant vegetation surfaces in agricultural land management. Among different methods used to measure the ETc, energy balance method is superior, especially in areas with shallow groundwater. Crop coefficient (Kc), a ratio of measured ETc and calculated reference ET, is used to indirectly estimate the crop water requirement. It is challenging to obtain since the Kc is related to the crop growth stage, soil moisture, and management practices. Using advanced instrumentation could provide soil, air and near surface variables to quantify the energy balance above the cropping land. In this project, I will measure the ETc using the near-surface energy balance for a crop with eddy covariance, Bowen ratio energy balance system and soil water balance approaches in a tile-drained field. Furthermore, Bowen ratio system results would be used to close the energy balance for the results using the eddy covariance method and reduce the uncertainty of the measured ETc. This study will provide measured ETc for the study period of a planted crop, and suggest an accurate Kc for the region. Comparison of existing and developed Kc values would be provided to clarify the effect of accurate ETc measurement on agricultural water management.