气候变化背景下湖南油菜气象灾害风险评估

Meteorological Disaster Risk Assessment of Oilseed Rape under Climate Change Conditions

利用湖南省96个气象站1961-2010年气象资料,采用相关分析方法,筛选出苗床期干旱、大田苗期干旱、越冬苗期冻害、蕾薹期冻害、开花期低温连阴雨、结荚绿熟期连阴雨和成熟收获期连阴雨共7个制约湖南油菜高产的气象灾害因子,结合专家经验确定各因子的权重系数,建立油菜气象灾害综合风险指数,基于地理信息系统进行湖南油菜气象灾害风险评估。结果表明,湖南省油菜气象灾害的高风险区主要分布在湘东北和湘东南局部地区,微风险区分布在郴州西南部和张家界大部,湘中一带的娄底、邵阳中北部、湘潭、长沙及湘北的岳阳、益阳等地以较高风险为主,其它地区以中风险和低风险为主。对1961-1990、1971-2000、1981-2010年气候整30a的年代际油菜风险的变化分析表明,在气候变暖背景下,湖南油菜高风险和较高风险区域略有减小,低风险和微风险区域有所增加。研究结果可为冬季油菜生产布局提供科学依据。

With meteorology data of 96 stations during 1961 -2010, authors adopted correlation analysis method to choose seven meteorological disasters which restrict the yield of oilseed rape in Hunan and determined the weight coefficients of these factors with experts experience. Integrated risk index was established to assess meteorological disaster risk of oilseed rape in Hunan based on GIS. The seven disasters were drought at seedbed stage, drought at seedling stage in field, frost at seedling stage overwinter, frost at flower budding stage, continuous rain with low temperature at blooming stage, and continuous rain at pod setting and harvesting stages. The results showed that northeast and southeast of Hunan were the main local areas at the highest risk, and southeast of Chenzhou and most area of Zhangjiajie were at micro risk. Central Hunan including Loudi, north and center of Shaoyang, Xiangtan and Changsha, and north of Hunan including Yueyang, Yiyang were at higher risk. Other areas were at intermediate risk or low risk. The decadal change of oilseed rape risk during different periods of 1961 to 1990, 1971 to 2000, and 1981 to 2010 were also analyzed. The range of the highest risk and higher risk showed a little decrease and the range of the low risk and micro scientific evidence risk showed a little increase in the context of global warming. The research result could provide for production distribution of oilseed rape.