基于水分亏缺指数的四川省水稻干旱灾害综合风险评价

Comprehensive Risk Assessment of Rice Drought Disaster in Sichuan Province Based on Crop Water Deficit Index

四川是我国水稻重要产区之一,水稻产量在全国居于前列.干旱是四川水稻最重要的农业气象灾害之一,研究干旱对水稻的综合风险,对保障四川水稻安全生产乃至全国粮食安全有重要意义.利用四川水稻产区26个观测站点的气象观测资料、农业气象观测资料、社会统计资料、基础地理信息数据,以水稻全生育期为研究时段,选取水分亏缺指数、产量变异程度、水稻生长暴露程度、有效灌溉率、人均GDP等影响因子,构建出四川水稻危险性、脆弱性、暴露性、防灾减灾能力评价模型,进而构建出四川水稻干旱灾害综合风险评价模型,对四川水稻产区进行区划.结果显示:干旱高风险区和次高风险区主要分布于盆东平行岭谷区大部、盆中丘陵区北部、盆北深丘低山区西部和东部;中等风险区主要分布于盆中丘陵区东北部和东南部、盆北深丘低山区中部、盆南丘陵低山区西南部、川西南山地大部;次低风险区和低风险区主要分布于成都平原区和盆中丘陵区的成德绵乐经济带及其辐射区域.四川水稻产区单季稻干旱灾害地区差异明显,各地应根据风险区划特点,结合本地实际进行选种和种植,并采取多种防灾减灾措施减轻干旱损失.

Sichuan is one of the important rice producing areas in China,and the rice yield ranks in the forefront of the country.Drought is one of the most important agrometeorological disasters of rice in Sichuan Province.It is important to study the comprehensive risk of drought on rice for ensuring the safety of rice production in Sichuan Province and even the national food security.In this study,the meteorological observation data,agricultural meteorological observation data,social statistical data and basic geographic information data from 26 observation stations in Sichuan rice-growing areas from 1980 to 2017 were used to establish the evaluation models of risk,vulnerability,exposure and disaster prevention and mitigation capacity for Sichuan rice by taking the whole growth period of rice as the research period,selecting crop water deficit index,yield variation degree,rice growth exposure degree,effective irrigation rate and per capita GDP as the influencing factors.Then,the Comprehensive Risk Assessment Model of rice drought disaster in Sichuan was constructed for zoning the rice production area in Sichuan.The results showed that the high-risk and medium-high-risk areas of drought were mainly distributed in most of the parallel ridge-valley areas in the east of the basin,the north of the hilly areas in the middle of the basin,and the west and east of the deep hilly and low mountainous areas in the north of the basin.The medium risk areas are mainly distributed in the northeast and southeast of the hilly area in the middle of the basin,the middle of the low hilly area in the north of the basin,the southwest of the low hilly area in the south of the basin,and most of the mountainous areas in the southwest of Sichuan.The sub-low risk area and low risk area of drought disaster risk are mainly distributed in the Chengdu Plain and the Cheng-De-Mian-Le Economic Belt and its radiation area in the hilly area of the basin.The regional difference of drought disaster of single cropping rice in Sichuan rice production area is significant.According to the characteristics of risk regionalization,selection and planting of rice should be carried out in consideration of the local conditions,and various disaster prevention and mitigation measures should be taken to reduce the drought loss.