Spatiotemporal Variation in Actual Evapotranspiration and the Influencing Factors in Ningxia from 2001 to 2020

Huihui Liu; Dongdong Song; Jinling Kong; Zengguang Mu; Qiutong Zhang; Xixuan Wang

doi:10.3390/ijerph191912693

Spatiotemporal Variation in Actual Evapotranspiration and the Influencing Factors in Ningxia from 2001 to 2020

Int J Environ Res Public Health. 2022 Oct 4;19(19):12693. doi: 10.3390/ijerph191912693.

Authors

Huihui Liu^{1

2}, Dongdong Song³, Jinling Kong¹, Zengguang Mu⁴, Qiutong Zhang¹, Xixuan Wang¹

Affiliations

¹ College of Geological Engineering and Geomatics, Chang'an University, Xi'an 710054, China.
² Institute of Natural Resources Survey of Ningxia, Yinchuan 750002, China.
³ School of Public Administration, China University of Geosciences (Wuhan), Wuhan 430074, China.
⁴ Natural Resources Information Center of Ningxia, Yinchuan 750002, China.

Abstract

Surface evapotranspiration (ET) is an important part of the hydrological cycle. Based on the MOD16 ET product and the data collected by meteorological stations, this study investigated, for the first time, the characteristics, variation trend and influencing factors of actual ET in Ningxia from 2001 to 2020 along temporal and spatial scales using the Theil-Sen median trend analysis, Mann-Kendall test and Hurst index, and predicted the future trend of ET. The results revealed a strong correlation between the MOD16 ET product and ET data collected at meteorological stations (r = 0.837, R² = 0.701). Over the past 20 years, the annual ET in Ningxia showed an overall increasing trend, and the proportion of the increasing area was 96.58%. Quarterly ET varied over time, with the highest value in the third quarter and the lowest value in the second quarter. Annual ET showed a positive correlation with normalized difference vegetation index (NDVI), surface temperature and precipitation but no correlation with relative humidity. Additionally, the Hurst index revealed areas showing a persistent increase in ET, accounting for 84.91% of the total area, indicating that the future trend of ET in Ningxia is consistent with the past trend.

Keywords: MOD16; NDVI; actual evapotranspiration; future trend; meteorological factors; variation trend.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

China
Climate Change*
Ecosystem*
Temperature

Grants and funding

This research was funded by the National Natural Science Foundation of China (grant number: 42071345). This work was supported by the Department of Science and Technology of Shanxi Province Key Research and Development Projects (grant number: 2020ZDLSF06-07).