关键词: 信息量法, 层次分析法, 油松毛虫, 风险评估, 遥感

Abstract: [Objective]The pine caterpillar, Dendrolimus tabulaeformis (Lepidoptera:Lasiocampidae) is a serious defoliator in the stands of Pinus tabulaeformis in China. In this study, a multi-factor disaster risk assessment method is proposed for prevention and early warning before the pest disaster, which is based on climate, topography and other factors that affect disaster occurrence and disaster grade.[Method] The distribution range of P. tabulaeformis was extracted from Landsat data in Western Liaoning Province. The eight risk assessment factors, including elevation, aspect, slope, rainfall, accumulated temperature, sunshine hours, disaster degree in the previous year and the distance from the disaster area in the previous year, were collected, and then the weight of each factor was determined by analytic hierarchy process. Finally, a weighted information model was established. Combining with the spatial analysis method of GIS, the disaster risk of P. tabulaeformis was classified into five levels:extremely low-risk area, low-risk area, medium-risk area, high-risk area and extremely high-risk area. A hazard zone map was made with the above information and the accuracy is verified by comparing with the monitoring result of actual disaster degree.[Result] 1) According to the principle of information quantity method, the greater the amount of information, the greater the risk of disaster. The information values of each factor classification calculated in this paper coincided with the biological characteristics of D. tabulaeformis. 2) The mapping results showed that in 2017 high-risk area and the extremely high-area in the study area was mainly distributed in the northern part of Jianping county. Medium-risk areas were mainly located in the northern part of Jianping County and the interchange between Jianping and Lingyuan. The risk of the insect pest in other areas was low. The mapping results were consistent with the actual survey results. 3) The relationship between the finally classified middle-low risk areas and the actual defoliation rate of P. tabulaeformis is obvious. Around 90.32% of the actual infested P. tabulaeformis forests are classified into high risk areas and extremely high areas.[Conclusion]Based on the weighted information model, the risk assessment of pine caterpillar disaster comprehensively considers the difference of the impact of different evaluation factors on the disaster occurrence. The result of risk zoning is accurate and has certain application value. It can provide technical basis for the risk assessment of forest pests and diseases in large areas.

Key words: information quantity, analytic hierarchy process(AHP), Dendrolimus tabulaeformis, risk assessment, remote sensing