Water consumption in summer maize and winter wheat cropping system based on SEBAL model in Huang-Huai-Hai Plain, China

Crop consumptive water use is recognized as a key element to understand regional water management performance. This study documents an attempt to apply a regional evapotranspiration model (SEBAL) and crop information for assessment of regional crop (summer maize and winter wheat) actual evapotranspiration (ETa) in Huang-Huai-Hai (3H) Plain, China. The average seasonal ETa of summer maize and winter wheat were 354.8 and 521.5 mm respectively in 3H Plain. A high-ETa belt of summer maize occurs in piedmont plain, while a low ETa area was found in the hill-irrigable land and dry land area. For winter wheat, a high-ETa area was located in the middle part of 3H Plain, including low plain-hydropenia irrigable land and dry land, hill-irrigable land and dry land, and basin-irrigable land and dry land. Spatial analysis demonstrated a linear relationship between crop ETa, normalized difference vegetation index (NDVI), and the land surface temperature (LST). A stronger relationship between ETa and NDVI was found in the metaphase and last phase than other crop growing phase, as indicated by higher correlation coefficient values. Additionally, higher correlation coefficients were detected between ETa and LST than that between ETa and NDVI, and this significant relationship ran through the entire crop growing season. ETa in the summer maize growing season showed a significant relationship with longitude, while ETa in the winter wheat growing season showed a significant relationship with latitude. The results of this study will serve as baseline information for water resources management of 3H Plain.