朝阳市玉米不同生育阶段干旱灾害风险预测

Prediction on Drought Risk for Maize in Different Growing Stages in Chaoyang City

利用辽宁省朝阳市1970-2006年逐旬降水量数据和玉米产量数据,采用多尺度SPI指数、判别式分析法、滑动直线平均法建立玉米干旱灾害风险预测模型,以探寻一种预测玉米不同生育阶段干旱灾害风险的新方法。结果显示,模型预测准确率随着生育阶段的推进不断提高,平均可达83.8%;模型对高风险、低风险、无风险组预测的准确率不同,其中高风险预测准确率最高,可达90.9%,无风险组最低,为78.9%;其中乳熟阶段准确率提高幅度最大,由前一阶段的67.6%提升到83.8%,表明乳熟阶段是否干旱对最终产量影响更明显,是玉米的关键生育期。研究表明,将多尺度SPI与判别式分析法相结合进行风险预测准确率较高,能够满足业务服务需求,尤其适合于干旱为主导灾害的地区。

The prediction model to drought risk for maize in different growing stages was established,by using multi-scale SPI,discriminant analysis and linear sliding average method,based on the data of precipitation during each ten days and maize yield in Chaoyang city,Liaoning province.The results showed that the accuracy of the model increased with the growing stages promoted and got to 83.8%.Accuracy of the model for high-risk group,low-risk group,and normal group were different,which was highest and could be 90.9% to high-risk group,and was lowest and could be 78.9% to normal group.It had highest accuracy at milky-ripening stage,which increased to 83.8%from 67.6% at former stage.It indicated that the milky-ripening stage was the key growing stage for maize,had more prominent influence on the final yields.The results indicated that the prediction model had high accuracy,could meet the demand of business service,especially for the regions where drought was the main disaster.