Compound Impacts of Drought and Soil Salinity on Maize Productivity

Abstract

Intensifying soil drought poses a significant threat to maize yields in China. However, the compounding effects of soil drought and salinity remain poorly understood. Here, we analyze maize yield trends in China from 1982 to 2016 and show that an increase in the total number of drought days is associated with significant yield declines. We find that the co‐occurrence of drought and soil salinity (CODS) amplifies maize yield‐loss risk, with the probability of yield loss exceeding 20% and remaining higher than under drought alone. Compared with drought‐only conditions, CODS increases the additional yield‐loss risk by approximately five percentage points. These findings are further supported by analyses in the North China Plain and the Songnen Plain, where irrigated areas exhibit more negative yield anomalies than rain‐fed areas under comparable drought conditions, suggesting that irrigation practices may be associated with increased soil salinity and thereby reduce the effectiveness of drought mitigation. This study underscores the urgent need for integrated soil and water management strategies that simultaneously address drought resilience and salinity control to safeguard China's maize production.