Spatial And Temporal Changes Of Environmental Factors And Their Effects On Evapotranspiration In Wuhai City

Accurate measurement of evapotranspiration is the key to improve plant water use efficiency and plays a vital role in the development of agricultural technology in China.This study takes Wuhai City,Inner Mongolia as the research object.Based on the Landsat satellite image data from 2019 to 2020,the daily evapotranspiration in the growing season of the region is retrieved by SEBAL model,and the temporal and spatial variation laws of different meteorological factors and their impact on evapotranspiration are analyzed by SPSS software.The results show that:(1)Using Landsat 8 remote sensing image data,the surface evapotranspiration retrieved based on SEBAL model has achieved good inversion accuracy.(2)The annual average daily evapotranspiration of the whole study area is between0.02-6.31 mm,and the average daily evapotranspiration of the study area shows a gradual increasing trend from north to south.(3)The order of daily evapotranspiration of different land use types from large to small is water area(5.93mm)> forest land(4.84mm)> cultivated land(4.31mm)>residential land(4.26mm)> bare rock land(3.67mm)> sandy land(3.50mm).(4)The daily average evapotranspiration in May,June,July and August is2.86mm/day,3.4mm/day,5.89mm/day and 4.31mm/day respectively.The whole shows the law of July > August > June > May.(5)The effects of different meteorological factors on daily evapotranspiration are surface temperature > surface reflectance > average temperature > NDVI > wind speed.The results can provide data reference for agriculture,landscaping and irrigation in Wuhai City.