宁夏枸杞炭疽病害天气指数保险研究

Study on Weather Index Insurance of Colletotrichum Gloeosporioides Penz of China Wolfberry in Ningxia

利用宁夏枸杞主产区中宁1971-2016年地面气象站逐日观测资料和1975-2001年枸杞产量资料,分析中宁6-9月气候特征,构建枸杞炭疽病发生发展的气象条件指标,并以7月至9月上旬炭疽病气象条件等级累计值作为枸杞炭疽病天气指数,结合典型灾害年样本建立中宁枸杞炭疽病天气指数与减产率的关系模型,初步设计了天气指数产品赔付方案。结果表明:枸杞炭疽病的发生与平均气温、相对湿度和降水日数显著相关,适温、高湿且降水量较大的7月至9月上旬是宁夏中宁枸杞炭疽病的易发时段,故将逐日气象条件按照不同阈值划分为不适宜、基本适宜、较适宜、适宜和非常适宜5个等级。近46 a来,增暖趋势有利于增加中宁枸杞炭疽病的发生风险,而相对湿度下降和降水日数减少一定程度上不利于炭疽病的发生。利用聚类分析方法,将枸杞炭疽病天气指数由轻到重划分为5个等级,并以指数6作为触发值,确定等级赔付标准。在此基础上,基于历史灾害平均损失率厘定了中宁枸杞炭疽病天气指数不同触发条件下纯保险费率为3.2%~8.6%,保费为1440~3870元·hm^-2。

Based on the daily surface meteorological observation data from 1971 to 2016 and yield data of China wolfberry from 1975 to 2001 in Zhongning of Ningxia, the climatic characteristics from June to September were analyzed, and the meteorological condition indices of occurrence and development of Colletotrichum gloeosporioides Penz of China wolfberry were established. On this basis, the cumulative values of meteorological index grades from July to early September were defined as Colletotrichum gloeosporioides Penz weather index of China wolfberry, and the relationship model between weather index and yield reduction rate was established based on typical samples of disaster. The insurance claim schemes based on weather index were designed preliminarily. The results show that the occurrence of Colletotrichum gloeosporioides Penz of China wolfberry was significantly related to mean air temperature, relative humidity and rain days. The suitable temperature, high humidity and more precipitation was easily to occur Colletotrichum gloeosporioides Penz of China wolfberry from July to early September in Zhongning of Ningxia, so the daily meteorological conditions were divided into five grades including unsuitable, basically suitable, less suitable, suitable and very suitable levels according to different thresholds. The climate warming was beneficial to improve risk of Colletotrichum gloeosporioides Penz of China wolfberry, while the decline of relative humidity and rain days wasn’t conductive to cause Colletotrichum gloeosporioides Penz to some extent from 1971 to 2016. The weather index of Colletotrichum gloeosporioides Penz was divided into five grades by using cluster analysis, and the payment standard of weather index with different levels was determined by using weather index of 6 as payment trigger value. Considering the average loss rate of historical disasters, the premium rates based on the weather index of Colletotrichum gloeosporioides Penz under different trigger value conditions were defined as 3.2% to 8.6% in Zhongning, and the corresponding premiums were 1440 to 3870 Yuan per hectare.