农业气象灾害灾情等级划分与年景评估

利用福建省1980—2004年农业成灾面积资料,计算主要气象灾害(干旱、洪涝、风雹和低温冻害)的成灾率及其变异值,在此基础上将4类气象灾害分为5个等级,并给予相应的分值,采用灰色关联分析方法,计算4类气象灾害与总灾害的关联度,得到其对农业生产的影响权重为旱灾>冻害>风、雹灾>水灾,建立农业气象灾情的综合评价模型并对25a的农业年景进行分级和综合评价。结果表明:福建农业气象灾害中灾及以下灾情的出现频率占到了总数的88%,灾情最重的年份为1999年,灾情最轻的年份为1984年;农业气象灾害对农业生产的危害随年代增大,而且波动加剧。

Grade classification and annual case assessment of agro-meteorological disasters in Fujian Province

Based on the statistic data of disaster-affected agricultural area in Fujian Province from 1985 to 2004, the affecting rates and variation values of the main agro-meteorological disasters including drought, flood, wind and hailstone damage, and cool and frost injury were calculated, and five grades were classified. Through grey correlation analysis, the correlation degree between the total disaster and each of the main disasters was worked out, and the weights of the affecting factors were obtained. An integrated assessment model was built to estimate the affecting degree of the disasters in the last 25 years, and the results showed that the appearance frequency of light and medium degree disasters was 88%. The most serious disasters happened in 1999, and the lightest ones were in 1984. The harmfulness of agro-meteorological disasters on agricultural production increased with time, and the fluctuation tended to be intensified.