Remote Sensing Interpretation of Crop Water Consumption in Irrigation Areas of Karst Mountainous Regions in Guizhou Province

WU Haikuan; LI Changjiang; PENG Yun

doi:10.3969/j.issn.1004-7328.2026.07.003

Abstract：To accurately grasp the crop water consumption patterns in irrigation areas of karst mountainous regions in Guizhou Province and promote efficient water resource utilization and sustainable agricultural development,based on NASA(National Aeronautics and Space Administration)remote sensing images and other data from 2021 to 2023,this paper adopts the flux decomposition method to interpret crop water consumption,and verifies and analyzes the interpretation results combined with evaporation data from typical meteorological stations.The results show that in terms of temporal distribution,crop water consumption exhibits obvious seasonal variation,reaching its peak in summer due to high temperatures and vigorous crop growth,with decadal water consumption of 30-50 mm;it drops to its lowest value in winter due to low temperatures and crop dormancy,with decadal water consumption less than 10 mm;interannual differences are mainly affected by precipitation fluctuations.In terms of spatial distribution,water consumption is relatively high in some areas of the south and east,with local areas exceeding 650 mm,corresponding to the distribution of rice-growing areas and high precipitation zones;low-value areas are locally below 250 mm,corresponding to dry farming areas,low precipitation zones,and karst landform areas;other areas have water consumption mainly concentrated at 400-500 mm.Terrain water retention capacity and differences in crop water demand coefficients(rice>flue-cured tobacco>corn)jointly drive the spatial differentiation of crop water consumption.Verification results show a high correlation between observed values and modeling results,and the interpretation results have reliable accuracy.The research results can provide reference for agricultural water resource management and crop water consumption monitoring in irrigation areas of Guizhou Province.