Forest Health Assessment Of Xinhua County Based On SOM Neural Network

As a new field of current forestry and ecological protection, Forest health assessment can provide the basis for the formulation of scientific forest protection measures and have important guidance function and a higher theoretical and practical significance of improving the level of sustainable forest management. Xinhua County is a key forest district and county in Hunan Province, a key forestry ecological engineering County construction, on the evaluation of forest health situation in Xinhua County, which is not only conducive to decision makers and research in a timely and accurate understanding and grasp the new County of forest health status, which provide references for the sustainable management of forests in the study area, but also enriches and supplement of forest health assessment in the field of research object, content and method.By making use of forest resource inventory data for management in Xinhua County in 2014, the study applied self organizing feature map (SOM) neural network to the forest health evaluation field, combined with the geographic information system (GIS) technology, based on forest management in small scale, to evaluate forest health in Xinhua County of quantitative classification, and based on the reason analysis and forest health management measures discussion, get results are as follows:(1) From four aspects of the complete structure, function stability, system energy and sustainability, to constructed a set of forest health evaluation index system based on the small scale for the arbor forest, the bamboo forest, the shrub forest by principal component analysis, a combination of quantitative and qualitative analysis method in the study area.(2)SOM neural classification network model was constructed based on the selection of index for evaluating health, Xinhua County forest health is divided into five classes:Ⅰ,Ⅱ,Ⅲ, Ⅳ,Ⅴ, respectively, on behalf of the unhealthy, sub-health, is health, health and good health. According to the evaluation results showed that the overall health of Xinhua County, the forest is not high, mainly in the relatively healthy state. Among them, high-quality health, health, healthy, sub healthy and unhealthy small number respectively 12378,18454,28339,14427,13422, respectively, accounted for the total class a number of 14.2%,21.2%,32.6%,16.6% and 15.4%; in good health, healthy, more healthy, sub healthy and unhealthy levels of sub compartment area were 26309.5hm2,43426.9hm2,67726.4hm2,31638.0hm2 and 34866.6hm2, respectively accounting for small total area of 12.9%,21.3%,33.2%, 15.5% and 17.1%.(3)The study on the origin, type, forest type, age group, and the dominant tree species health were analyzed to reach the conclusion that the cause of forest health status being not ideal is mainly due to the unreasonable structure of forest types, and forest structure is unreasonable, the age group structure is not reasonable.(4)Integrated forest health assessment results and analyzes the reasons, in view of the problems encountered by the forest of the study area in terms of sustainable development, puts forward strengthening forest tending, optimization of stand structure, increase closing hillsides to facilitate afforestation and food diversity protection; adjusting forest structure, realize the classification management, control of cutting quota, reduce felling yield; increase the intensity of forest production, full range management, adjusting the structure of age groups such as measures to improve forest health situation in study area, so as to build a sustainable development of green ecological Xinhua to provide strong support.