基于网格脆弱性曲线的世界小麦旱灾风险评价

Drought Risk Assessment on World Wheat Based on Grid Vulnerability Curves

旱灾是世界上影响范围最广、造成农业损失最大的自然灾害之一,同时,在全球变化的背景下,旱灾风险呈现加重的趋势。评价农业旱灾风险并进行有效的防范是保障粮食安全的重要措施。借助EPIC模型,假定0.5°网格为均值单元,使用灌溉情景法模拟全球均值网格的小麦旱灾脆弱性曲线。结合历史气象数据评价全球小麦的干旱致灾因子,最后计算了全球小麦因旱灾导致的产量损失风险,并编绘了全球小麦旱灾风险图。结果显示:1中国、俄罗斯、美国/哈斯克斯坦为风险排名前三的国家,归一化后的风险指数分别为0.53、0.22和0.19;2春小麦的旱灾风险要高于冬小麦。在已有的作物旱灾风险评价研究基础上,同时兼顾了脆弱性评价的空间分辨率和表示精度,建立了与风险评价空间分辨率相一致的小麦旱灾脆弱性曲线,从而极大地提升了区域旱灾风险评价,特别是大尺度风险评价的准确度。

Drought is one of the world＇s natural disasters of the widest influence and greatest loss for agriculture.Under the background of global change,drought risk has shown an increasing trend.Assessment and effective prevention on agricultural drought risk is an important measure to ensure food safety.With the help of EPIC model,assuming that the 0.5 degree grid is the average unit,wheat drought vulnerability curve of global mean grid is simulated by irrigation scenario method.Combining with the historical meteorological data,drought disaster causing factors of the global wheat are evaluated.Finally,yield loss risk of the global wheat causes by drought is calculated and the drought risk map of the global wheat is drawn up.Results show that：① China,Russia and USA /Hasikesitan are the first three countries in the risk ranking,risk index normalized are respectively 0.53,0.22 and0.19; ② Spring wheat drought risk is higher than that of winter wheat.Based on the existing research on the evaluation of drought risk crops,taking into account the spatial resolution and accuracy of the vulnerability evaluation,wheat drought vulnerability curve consistent with spatial resolution of risk assessment is established,regional drought risk assessment is thus greatly enhanced,especially the accuracy of large scale.