LAUSR

Understanding the change of water requirement (ET) for crop production under climate change can provide scientific support for the management of agricultural water resources. The objective behind this study was to analyze spatiotemporal distribution characteristics of ET, effective rainfall (Pe), irrigation requirement (IR) and aridity index (AI) of winter wheat, and evaluate the driving force of ET changes as a result of the variation of climatic factors. Daily meteorological data from 18 meteorological stations from 1969 to 2019 distributed throughout Shandong Province, China were collected. Five climatic variables including maximum daily temperature (Tmax), minimum daily temperature (Tmin), relative humidity (RH), wind speed (WS), and sunlight hours (SH), were selected to identify their contribution to the variability of ET. Results indicated that (1) ET distribution differed significantly both in temporal and spatial scale on a general, and decreased -14.11-3.88 mm decade. (2) Tmax was the most influential climatic variable related to ET variability with sensitivity coefficient of 0.36, followed by RH (-0.34), SH (0.13), WS (0.11) and Tmin (-0.07). (3) Declines of WS and SD were indicated by the decrease of ET while the increase of Tmax and the decrease of RH contributed to enhancing ET.