Based on MODIS gross primary productivity(GPP)and evapotranspiration(ET),the vegetation water use efficiency(WUE)in Dali Bai Autonomous Prefecture was estimated,and trend analysis method was used to analyze the relationship between vegetation WUE and al-titude in the study area.The result showed that the vegetation WUE in Dali Bai Autonomous Prefecture from 2016 to 2020 was 1.93-2.22 g/(m2·mm),with an average of 2.07 g/(m2·mm),the annual mean value of vegetation WUE in the study area peaked in 2019.There were differences in the distribution of vegetation WUE between the east and west in Dali Bai Autonomous Prefecture.In the past 5 years,the WUE in the east had mainly shown an upward trend,and the upward trend of WUE in the southeast region was more obvious.The rising and falling areas of WUE in the western region were basically the same,while the upward trend of WUE in the northwest region was relatively slow.The changes of vegetation WUE at different altitudes were different,the annual mean value of vegetation WUE in the study area showed a nor-mal distribution law of first increasing and then decreasing with altitude,the annual mean value of WUE in the area with an altitude of>2 500-3 000 reached the highest at 2.14 g/(m2·mm).
关键词
水分利用效率/时空变化趋势/MODIS/海拔/大理白族自治州
Key words
Water use efficiency/Temporal and spatial variation trend/MODIS/Altitude/Dali Bai Autonomous Prefecture
维普
万方数据