基于EPIC模型的云南元谋水稻春季旱灾风险评估方法

摘要

Drought risk assessment is of great significance to reveal drought regularity and reduce drought losses. Taking Yuanmou county as the study area, the frequency of spring drought from 1961 to 2010 were calculated using copula function method. Similarly, the correlated drought losses under different irrigation level were calculated using EPIC model. Then it fitted the distribution curve of spring drought frequency and drought losses. The case study results indicate that there is the correlation of Logarithmic function be-tween drought frequency and drought losses, and the coefficient of determination is above 0.7. In addition, the effect of irrigation to reduce drought loss is significant. The distribution curve can quantitatively reflect the relation among drought frequency, irrigation level and drought loss, therefore, the method is applicable to the drought risk assessment in Yuanmou county,Yunnan province.%旱灾风险评估对于揭示旱灾发生规律，减少旱灾损失具有重要意义。以云南元谋县水稻1961-2010年的春季干旱为例，利用copula函数计算干旱发生频率，根据EPIC模型计算干旱在不同灌溉水平下的旱灾损失率，拟合干旱频率-旱灾损失率的分布曲线。云南元谋县实例研究表明，水稻春季干旱发生频率与其旱灾损失率之间基本符合对数函数的趋势关系，决定系数R2在0.7以上，灌溉水量对于减少旱灾损失的作用显著。建立的干旱频率-灌溉水平-旱灾损失率分布曲线，可作为研究区水稻春季旱灾风险的定量评估方法。