中文摘要：

基于信息扩散理论,从福建省（1998—2014年）森林病虫害发生的面积、范围和程度3个方面建立风险概率模型。分别分析森林病害和虫害的发生情况、发展趋势,并选取年发生总面积和发生率2个指标对森林病虫害发生风险的范围和程度展开研究。结果表明：（1）福建省森林病害与虫害发生严重,其中森林虫害发生面积较大,发生程度较高;（2）轻度和中度森林病害年发生面积之和的平均值为3.1万hm~2,年发生面积在平均值以上的概率为50%左右,重度森林病害年发生面积1910~2300hm~2的周期为3~5a,重度森林虫害年发生面积超过1万hm~2的概率为72.508%;（3）森林病虫害的各指标波动与其发生总面积的波动趋势和频率不一定完全一致,其中重度森林病害年发生面积所占比例波动较大且具有上升趋势;（4）森林病虫害年发生总面积和发生率在各自平均值以上的概率均为50%左右。

英文摘要：

Based on the information diffusion theory,the probability model on risk of forest pests in Fujian Province was built from three aspects including the area,range and extent of the forest pests occurrence from 1998 to 2014. Then,analyzing the situation and development trends of forest diseases and insect pests,and two indexes（total occurrence areas of forest pests and forest occurrence rate） were selected to analyze the range and extent of occurrence. The results showed that：（1） The situation of forest diseases and forest insect pests are serious in Fujian province,which the occurrence area of forest insect pests is larger and it is a higher degree of occurrence;（2） The average annual occurrence area of mild and moderate forest diseases is about 31 000 hm~2,and the probability of exceeding the mean annual of occurrence area is about 50%. Moreover,the cycle of the severe forest diseases with occurrence area of 1 910 ~ 2 300 hm~2 is about 3 ~ 5 years. The probability of severe forest insect pests with the occurrence area over10 000 hm~2 is about 72.508%;（3） The fluctuation of each index of forest pests is not entirely consistent with fluctuation trend and frequency of its total occurrence area,in which the proportion of severe forest diseases occurrence area has an upward trend and fluctuates wildly;（4） Both of the probability of over mean annual total occurrence area and rate of forest pests are about 50%.