Studies On Health Assessment System Of Plantations At The Southloess Plateau

Due to the special conditions of climate、 geomorphology、 soil and highly fragileecosystem on the loess plateau, plantation ecosystem sustainable development is thefundamental aim of forest management in this region. Black locust (Robiniapseudoacacia)、 Chinese pine (Pinus tabulaeformis) and arborvitae (Platycladus orientalis)are the main afforestation species in south loess plateau, they play an important role inbuilding and maintenance of forest ecosystems in this region.In this research, acacia、pine and arborvitae plantation were selected for the study. Plotsdistributed in the Loess Plateau of Shaanxi Province Yongshou, Baishui, Fufeng County,Chunhua, Fu County and County of Gansu Province. Using Analytic Hierarchy and clusteranalysis applied to built the construction of the health assessment system of Weibei areaplantations. Establishment of evaluation index system of forest health and completed a studyon evaluation of locust、Pinus tabulaeformis and platycladus orientalis plantation health. Theresults were as follows:(1) Capacity to assess health status and sustainable development of plantation as thegoal, from the structure (O), stand vigor (v), stress-resistance (r) features such as filters in thetarget evaluation index for ease of measurement. By comparing the change in differentage-weighted indexes set up evaluation index system. Significance test results show thatscreening evaluation index of high sensitivity、 strong applicability.(2) According to the result of Cluster analysis and growth retardation factor analysisabout health index calculation, the health of the plantation study area is divided into threecategories: health, sub-health and unhealthy. Determined by forest age acacia, pine,arborvitae plantation division standard individual health levels. Stand in a healthy conditionwith good potential for sustainable development; Sub-health condition forest have obstaclesfactors, those forests could back to health status by tending; Unhealthy conditions in thepresence of a number of obstacles stand factor, even if it is difficult to recover by bringinghealth.(3) Acacia plantations in health, sub-health and unhealthy conditions accounted for45.2%,42.9%and11.9%in the Loess Plateau; Chinese pine plantations in health, sub-health and unhealthy distribution of the total number of24.5%,56.1%and19.4%;Orientalis plantations in health, sub-health and unhealthy distribution accounted for18.4%ofthe total,57.9%,23.7%. Plantations in the Loess Plateau region indicates the overall healthstatus is not optimistic, bringing much-needed health operations.