Method for detecting earth surface evapotranspiration based on remote sensing earth surface temperature and vegetation coverage two-stage space

Abstract

A method for detecting earth surface evapotranspiration based on remote sensing earth surface temperature and vegetation coverage two-stage space comprises the following steps: 1, acquiring earth surface temperature and vegetation coverage by utilizing a remote sensing data product; 2, establishing the earth surface temperature and vegetation coverage two-stage feature space; 3, extracting the temperature of vegetation component and bare soil component by utilizing the earth surface temperature and vegetation coverage two-stage feature space; 4, calculating the evaporation ratio of vegetation and bare soil by combining the earth surface temperature and vegetation coverage two-stage feature space and a Priestley-Taylor formula; 5, calculating the available energy of the vegetation component and the available energy of the bare soil component according to a radiation income and outcome balance equation; 6, calculating the output vegetation evapotranspiration, soil evaporation and earth surface evapotranspiration through a binary pattern of earth surface evapotranspiration.

Description

technical field [0001] The invention relates to the field of remote sensing detection of surface evapotranspiration, in particular to a remote sensing detection method of surface evapotranspiration based on the feature space of surface temperature and vegetation coverage. Background technique [0002] Surface evapotranspiration is a key parameter in the surface water cycle process, directly or indirectly affecting the balance of surface moisture and heat. Surface evapotranspiration is mainly composed of two parts: vegetation transpiration and soil evaporation. Soil evaporation reflects the process of water in the soil entering the atmosphere through abiotic action and is closely related to surface soil moisture; while vegetation transpiration reflects the process of water in the soil entering the atmosphere through abiotic processes. The process of entering the atmosphere is closely related to the soil moisture in the root layer of vegetation. Generally, in agricultural app...

AI Technical Summary

Problems solved by technology

figure 1 The traditional feature space model shown in (a) takes into account the difference in response degree. The response degree of bare soil is large, and the response degree of vegetation is small, so the trapezoidal shape is formed; but the difference in response speed is not considered.

Regardless of the difference in response speed, there will be large errors in the inversion of vegetation and bare soil component temperatures, which in turn will lead to large errors in the estimation of vegetation transpiration, soil evaporation, and surface evapotranspiration, which directly affects agricultural drought monitoring and irrigation. Application effects of water demand estimation and crop yield forecasting

Images