The negative-positive feedback transition thresholds of meteorological drought in response to agricultural drought and their dynamics

Xiaoting Wei; Shengzhi Huang; Jianfeng Li; Qiang Huang; Guoyong Leng; Dong Liu; Wenwen Guo; Xudong Zheng; Qingjun Bai

doi:10.1016/j.scitotenv.2023.167817

The negative-positive feedback transition thresholds of meteorological drought in response to agricultural drought and their dynamics

Sci Total Environ. 2024 Jan 1:906:167817. doi: 10.1016/j.scitotenv.2023.167817. Epub 2023 Oct 13.

Authors

Xiaoting Wei¹, Shengzhi Huang², Jianfeng Li³, Qiang Huang¹, Guoyong Leng⁴, Dong Liu¹, Wenwen Guo¹, Xudong Zheng¹, Qingjun Bai¹

Affiliations

¹ State Key Laboratory of Eco-Hydraulics in Northwest Arid Region of China, Xi'an University of Technology, Xi'an 710048, China.
² State Key Laboratory of Eco-Hydraulics in Northwest Arid Region of China, Xi'an University of Technology, Xi'an 710048, China. Electronic address: huangshengzhi7788@126.com.
³ Department of Geography, Hong Kong Baptist University, Baptist University Road, Kowloon Tong, Hong Kong, China.
⁴ Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China.

PMID: 37838043
DOI: 10.1016/j.scitotenv.2023.167817

Abstract

There are complex bidirectional feedback relationships among different types of droughts (e.g., meteorological and agricultural droughts). As agricultural drought intensifies, meteorological drought response to agricultural drought may be changed from negative to positive feedback. Nevertheless, the negative-positive feedback transition thresholds of meteorological drought in response to agricultural drought and their dynamics have remained unsolved. Herein, we proposed a new quantitative method to characterize the mutual feedback between meteorological drought and agricultural drought based on the vine copula function for the first time in this study. The negative-positive feedback transition threshold and the sensitivity of the feedback were quantified under certain drought conditions. In order to investigate the feedback relationship dynamics under a changing environment, the total study period was evenly divided into two stages: stage 1 (1982-1999) and stage 2 (2000-2018). Finally, the random forest method was used to explore the dominant factors on the transition threshold. Results indicate that: (1) the negative-positive feedback transition thresholds in August is generally lower than June and July in mainland China, the basin with large threshold is the Southwest River Basin; (2) the sensitivity of meteorological drought in response to agricultural drought was higher in positive feedback than in negative feedback; (3) the transition thresholds of stage 2 was mostly reduced, while the feedback sensitivity of positive feedback was mostly increased; and (4) compared with the single factor, the land-meteorological coupling strength (the correlation between precipitation and soil moisture) dominants the negative-positive feedback transition threshold. This study sheds new insights into droughts feedback.

Keywords: Agricultural drought; Feedback relationship; Meteorological drought; Positive feedback; Transition threshold.