基于信息扩散理论的湖南省农业水旱灾害风险损失情景分析

Condition assessment on risk losses of agricultural flood and drought disasters in Hunan Province based on information diffusing principle

农业水旱灾害频发是制约湖南省粮食生产和社会经济发展的限制因子。选取1950—2009年湖南省农业水旱灾害成灾面积作为灾情资料,基于信息扩散理论风险评估模型,对不同情景下湖南省农业水旱灾害进行风险损失评估。结果表明:湖南省农业水旱灾害粮食最大经济损失频率从2年一遇至100年一遇,总体上呈递增趋势,且均经历了一个较大幅度递增、平缓递增和大幅度递增的过程;旱灾粮食最大经济损失值较水灾大,但水灾粮食最大经济损失值在20年一遇至50年一遇之间出现了激增趋势,当发生100年一遇的水灾时,粮食最大经济损失值出现了剧增趋势且超越了旱灾的相应粮食经济损失值。农业水旱灾害风险损失评估工作的开展,可为湖南省农业水旱灾害的防灾、减灾提供科学依据。

Agriculture flood and drought are important factors which drag down the economic and social development of the grainproducing areas in Hunan Province. Based on data of disaster area caused by agricultural flood and drought from 1950 to 2009 in Hunan Province, the paper assessed the risk losses of agricultural flood and drought disasters in Hunan Province by using information diffusing principle. The results showed that maximum grain economic losses caused by agricultural flood and drought disasters took on increasing trends all along, that is, obvious increasing, slow increasing, and great increasing trends from once-in-double-year to once-in-a-century. Generally, maximum grain economic losses caused by drought were more than that of flood, but maximum grain economic losses caused by flood increased greatly from once-in-twenty-year to once-in-a-fifty-year. When once-in-a-century flood occurred, maximum grain economic losses increased severely and exceeded that of drought. Researching on the vulnerability of agricultural flood and drought in Hunan Province has important meaning on resisting the agricultural disasters.