Agricultural Land Management Extends the Duration of the Impacts of Extreme Climate Events on Vegetation in Double–cropping Systems in the Yangtze–Huai Plain China

Extreme climate events can have severe impacts on both vegetation and the carbon cycle. However, whether land management exacerbates or mitigates the effects of extreme climate events on vegetation remains unknown. We investigated the case of an extreme precipitation event that occurred in a region dominated by double–cropping (DC) systems located in the Yangtze–Huai plain in China. Waterlogging disasters were triggered by an extreme precipitation event in October 2016, which severely affected the sowing and seedling emergence of winter crops (mainly winter wheat). The lack of sowing and low seedling emergence rate subsequently led to months of low growth, as evidenced by negative enhanced vegetation index (EVI) anomalies, especially from March to May 2017. Local agricultural meteorological monthly reports, government announcements, and winter wheat data based on statistics and remote sensing confirmed the reduced yields. The influence on vegetation ended in June 2017, when summer crops were planted. Our results demonstrate that, in such a DC system, when extreme events occur during the key sowing period, the impacts will continue through the entire crop growth period, until the next sowing. More generally, agricultural land management could extend the duration and magnitude of the impacts of extreme climate events on vegetation.