Risk assessment on agricultural drought in Southwest China

Abstract

TAgro-drought risk assessment is helpful for improving ability of regional disaster management and mitigating the drought-induced loss. We used historic precipitation, disaster loss and socio-economical data in Southwest China as the basic data. The assessment was performed on each of prefecture-level region. By using the consecutive rainless days to scale the drought severity, we developed different standards of indexes to judge drought severities. The standards were relying on seasons, crop types and crop growth stages. Moreover, we developed a model for each type of crop. This model could be used to calculate risk loss rate under different severities of drought. In the next step, we integrated risk loss of each type of crop to assess the regional drought-induced agriculture loss rate, by weighting average approach. Using the above method, we calculated the agro-drought risk loss rate of each prefecture-level region in the Southwest China. It is found that the moderate (loss rate: 3%∼6%) and high (loss rate: 6%∼9%) risk is dominant in the Southwest China. By ordering the area fraction with high risk and extreme risk, Yunnan Province and Chongqing Municipality are most severely affected by agro-drought and Sichuan Province and Guizhou Province are following.