Drought risk assessment for citrus and its mitigation resistance under climate change and crop specialization: A case study of southern Jiangxi, China

Abstract

Crop specialization has become an important way to promote agricultural efficiency and increase incomes for farmers in China. Under extreme weather conditions, this is likely to increase resistance to drought risk mitigation and lead to greater drought damage. In order to make more sophisticated mitigation policy decisions, it requires efforts to assess crop drought risk variability and its risk mitigation resistance in detail. This study focuses on citrus as a cash crop, using a case of southern Jiangxi. We first constructed a drought risk assessment system for citrus, and then geographic information technology was used to characterize the risk dynamics. The factor contribution model was applied to calculate the risk mitigation resistance. And the least square error (LSE) model was finally employed to classify risk mitigation resistance types. The results showed that citrus drought risk had fluctuated moderately over macro-regions in the past 30 years, but had varied dramatically at local scales. Citrus drought risk significantly increases during the bud bust to flowering, fruit expansion, and fruit maturation stages. Exposure contributed 33.23 % to drought risk fluctuations, specifically, mainly attributed to the amplification of drought exposure in the farmer and agricultural production sectors, while 14.95 % was derived from climate change. In large-scale citrus expansion areas, the improvement in drought mitigation capacity generally lags behind the increase rate of the exposure system. The LSE model showed that risk mitigation resistance type varied across regions at system level and indicator level. In addition, water scarcity has emerged as a widespread issue that limits drought risk mitigation. Generally, this study provides new insights into the measurement of drought risk mitigation resistance and its type identification, thus contributing to the safe supply of agricultural products and human well-being.