基于信息扩散理论的洞庭湖区农业旱灾风险评估

Risks Assessment of Agriculture Drought Disaster in Dongting Lake Area Based on the Information Diffusion Theory

以洞庭湖区2000～2009年的农业旱灾灾情统计数据为样本,运用基于信息扩散理论的模糊数学模型建立其在一定的论域上的模糊关系,然后据此得出旱灾指标的概率分布,继而得到旱灾指标的超越概率,最后分析洞庭湖区干旱的历史重现概率。结果表明：洞庭湖区几乎年年发生干旱;每5.2年就要发生1次受灾面积超过50%的中度干旱;约每20年就发生1次80%的严重干旱。

According to the date, i.e. the agricultural drought disaster statistics from 2000 to 2009 of Dongting Lake Area, the paper established its fuzzy relationship in a certain domain which used fuzzy mathematical model based on information diffusion theory, and then get the distribution of drought indicators as well as its exceedance probability. Finally, the probability of historical drought in Dongting Lake Area is analyzed and the results showed that the drought almost occurs in Dongting Lake Area every year and also the moderate drought which affected the area is more than 50 % happen every 5.2 a and the severe drought of affected area of 80 % occurs once about every 20 years and the extent of damage are mainly concentrated in 10 %～ 25 %. The drought situation of Dongting Lake Area is serious and agricultural drought can not be ignored there.