Authors: Lei Ji*, AFDS, contractor to USGS Earth Resources Observation and Science Center, Gabriel Senay, USGS Earth Resources Observation and Science Center, MacKenzie Friedrichs, KBR, Contractor to USGS Earth Resources Observation and Science Center, Matthew Schauer, C2G, Contractor to USGS Earth Resources Observation and Science Center, Olena Boiko, KBR, Contractor to USGS Earth Resources Observation and Science Center
Topics: Remote Sensing, Water Resources and Hydrology, Agricultural Geography
Keywords: cropland, evapotranspiration, irrigation water use, Kansas, water balance
Session Type: Virtual Poster
Start / End Time: 11:10 AM / 12:25 PM
Room: Virtual 51
Presentation File: Download
Kansas is one of the most productive agricultural states in the United States, where agricultural irrigation is a primary user of underground and surface water. Because of low precipitation and declining groundwater levels in western and central Kansas, sustainable management of irrigation water resources is a critical issue in the agricultural productivity of the state. The objective of this study is to analyze and characterize the water use and water balance in the croplands of Kansas. We used remote-sensing-based actual evapotranspiration (ETa), precipitation, soil moisture, and irrigation water use to calculate water balance for Kansas in 2015 at scales of counties, climatic divisions, and groundwater management districts (GMD). Results showed that the seasonal (May – September) precipitation, soil water storage change, and ETa are 528 mm, 80 mm and 555 mm, respectively. The annual irrigation water consumption was 38 mm for the croplands implying that irrigation water use was a small portion of water supply in the agriculture. The total volumetric irrigation water use was 3.24 km3 in the irrigated croplands within five GMDs in the western and south-central Kansas, while it was merely 0.38 km3 outside of GMDs. The multiple regression models of ETa against precipitation and irrigation water use were statistically significant with R2 values of 0.71 and 0.87, respectively, at county and climate division scales. Our study demonstrated the spatial patterns of crop water use and water balance in Kansas, which provided useful information for management of irrigation agriculture and water resources for the state.