Assessing the regime-switching role of risk mitigation measures on agricultural vulnerability: A threshold analysis

Vulnerability to agrometeorological disasters threatens agricultural production and food security, which calls for urgent risk mitigation measures. Previous studies have widely focused on constructing composite indices of agricultural vulnerability and projecting agricultural losses under changing climate. Only a few authors have delved into the patterns of mitigation practices in reducing agricultural vulnerability and enhancing the functioning of agricultural systems. To fill this research gap, our study assesses the spatial-temporal characteristics of agricultural vulnerability with respect to meteorological disasters (including droughts, floods, hail, low temperatures, and frost) from 2000 to 2021 across 31 regions (including 22 provinces, 4 direct-administered municipalities, and 5 autonomous regions) in China. Identifying a dynamic trend of agricultural vulnerability and making use of a regime-switching framework, a Markov regime-switching model is employed to examine the changing regimes underlying the link between agricultural vulnerability and crop yields. More importantly, regime-switching roles of four different mitigation practices (i.e., irrigation, reservoir capacity, soil loss control, and drainage systems) in moderating agricultural vulnerability are evaluated using panel threshold regressions. Our results show that: 1) The link between agricultural vulnerability and crop yields differs across regions, and regime-switching phenomena behind this link can be detected. 2) Irrigation systems, water reservoirs, and soil loss control can be effective tools for mitigating agricultural vulnerability. 3) With the above three measures, detrimental impacts of agricultural vulnerability on agricultural production can be reduced significantly when certain thresholds are hit. 4) Non-linear relationships between mitigation measures and crop yields require authorities to pay considerable attention to determining the effective scales of mitigation measures. Overall, this paper shall contribute to understanding the moderating role of risk mitigation measures in alleviating agricultural vulnerability and increasing crop yields, thereby providing insights into designing strategies and policies for sustainable agricultural production.