Dynamic variations of terrestrial ecological drought and propagation analysis with meteorological drought across the mainland China

Fei Wang; Hexin Lai; Yanbin Li; Kai Feng; Qingqing Tian; Wenxian Guo; Weijie Zhang; Danyang Di; Haibo Yang

doi:10.1016/j.scitotenv.2023.165314

Dynamic variations of terrestrial ecological drought and propagation analysis with meteorological drought across the mainland China

Sci Total Environ. 2023 Oct 20:896:165314. doi: 10.1016/j.scitotenv.2023.165314. Epub 2023 Jul 6.

Authors

Fei Wang¹, Hexin Lai¹, Yanbin Li², Kai Feng¹, Qingqing Tian¹, Wenxian Guo¹, Weijie Zhang³, Danyang Di⁴, Haibo Yang⁴

Affiliations

¹ School of Water Conservancy, North China University of Water Resources and Electric Power, Zhengzhou 450046, China.
² School of Water Conservancy, North China University of Water Resources and Electric Power, Zhengzhou 450046, China. Electronic address: liyb101@163.com.
³ Yinshanbeilu Grassland Eco-hydrology National Observation and Research Station, China Institute of Water Resources and Hydropower Research, Hohhot 010020, China.
⁴ School of Water Conservancy and Civil Engineering, Zhengzhou University, Zhengzhou 450001, China.

PMID: 37419335
DOI: 10.1016/j.scitotenv.2023.165314

Abstract

Ecological drought is a complex comprehensive process in which the water conditions for normal growth and development of vegetation are changed due to insufficient water supply. In this study, based on the remotely sensed vegetation health index (VHI) and the Famine Early Warning Systems Network Land Data Assimilation System (FLDAS) datasets from 1982 to 2020 in China, the Breaks For Additive Seasons and Trend algorithm (BFAST) was used to analyze the dynamic variations of ecological drought, the standardized regression coefficient method was applied to identify the primary drivers of ecological drought, and the regression analysis was adopted to reveal the coupling effect of atmospheric circulation factors on ecological drought. The results indicated that: (1) the ecological drought showed an overall decreasing trend during 1982-2020 in China, with a negative mutation point that occurred in April 1985; (2) spring drought and summer drought were more likely to occur in the South China, and autumn drought and winter drought were more likely to appear in the Sichuan Basin; (3) the propagation time from meteorological to ecological drought was shorter in summer (2.67 months) and longer in winter (7 months), with average r values of 0.76 and 0.53, respectively; (4) the Trans Polar Index (TPI), Arctic Oscillation (AO) and El Niño-Southern Oscillation (ENSO) had important impacts on ecological drought, which can be used as input factors of drought early warning system to improve the accuracy of drought prediction.

Keywords: Atmospheric circulation factor; China; Ecological drought; Propagation time; Vegetation health index.