Spatiotemporal patterns of evapotranspiration in the Xiangjiang River Basin from 2000 to 2020

Abstract

Evapotranspiration (ET) is a crucial parameter in the process of the hydrological cycle. It is vital for water resource management in the Xiangjiang River Basin (XRB) within Hunan Province of China to explore the spatial and temporal dynamic characteristics of ET. Based on MOD16, this study revealed the characteristics of spatiotemporal patterns of ET in the XRB from 2000 to 2020. We first applied land use data and change rate for overall trend analysis on ET. Then, we obtained migration routes of ET through standard deviation ellipse (SDE). Furthermore, we demonstrated the effects of monsoon and urban expansion on ET change. The results showed: (1) while the ET of artificial surfaces decreased the change rate in most regions of the XRB was 8.83%, indicating that the overall trend of ET in the XRB was increasing. (2) At 10-year intervals, the SDE center of ET all migrated in a clockwise direction. (3) The correlation between precipitation and ET is more obvious than that between temperature and ET. (4) With the influence of monsoon on precipitation in East Asia, the changes in precipitation are consistent with the ET change. HIGHLIGHTS Revealing the spatiotemporal characteristics of evapotranspiration (ET) in a river basin with the typical East Asian monsoon climate.; Using the standard deviation ellipse method to access the spatiotemporal migration routes of ET, which provides a new insight for ET mapping.; Demonstrating the implications of the monsoon and urban expansion on ET changes.;

Keywords

• driving factors
• evapotranspiration
• modis
• spatiotemporal patterns
• standard deviation ellipse
• xiangjiang river basin