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q Sharptooth oak forest as one of the major forest types Huoditang forest, build and maintain the area of ??forest ecosystems play an important role also plays an important water conservation function, while in the South-to-North Water Diversion Project. Sharptooth oak forest structural damage due to the long-term nature, human disturbance, degradation of forest stands. Therefore, this study attempts to investigate the the sharptooth oak Lin Jiankang situation and influencing factors from the point of view of the health assessment through the building at different scales Sharptooth Oak in Health Assessment Indicator System, the linear fit of the two kinds of evaluation results and analysis of the Health Assessment Indicator System of Sharptooth Oak in different time periods sharptooth oak Lin Jiankang condition, its findings are as follows: (1) with a sensitivity analysis filter out 21 indicators to establish the level of plot, AHP method to determine the index weight, a comprehensive evaluation by comprehensive evaluation of the 30 samples measured, the results show that: 30 samples in 16 unhealthy samples, the average health index is 0.316; There are a total of 11 samples at the sub-health state, health Index mean 0.469; 4 samples in a healthy state, the health index is an average of 0.577. Overall, Huoditang Sharptooth oak forest in a healthy condition, its health index mean 0.407. (2) analysis of the different forest types of Sharptooth oak Linjian Kang situation and show that: pine and oak mixed forest is sharper tooth oak Chunlin, broadleaf mixed forest health, their health index an average of 0.475, followed by broadleaved mixed forest health index mean 0.442 and Oak pure Lin Jiankang index was the lowest, at 0.369. Divided by level of health, of sharp teeth oak Chunlin overall in an unhealthy state, pine and oak mixed forest and broad-leaved mixed forest in a healthy condition. (3) the impact of the sharptooth oak Lin Jiankang factors research: stock volume, the biomass of the herbaceous layer, tree richness, the tree layer Shannon-Wiener Index, trees mingling index, leaf area index, the amount of carbon sequestration and oxygen release in to some extent, promote the healthy growth of the sharptooth oak forest. The amount of existing litter will inhibit the growth of the sharp teeth oak Lin Jiankang. Analysis of the different forest types Sharptooth oak Lin Jiankang situation: Sharptooth oak forest type, age structure, and human interference, and also to some extent affected Lin Jiankang. (4) In this study, a representative, the operability of strong principle target method of a small class level of Sharptooth Oak Health Assessment Indicator System, the criteria layer vegetation characteristics and soil characteristics, the target layer, including stand volume, average DBH of dominant trees average dominant tree species, canopy density and species composition of, updated tree species height, soil thickness, soil texture and soil dry humidity. And small class level Sharptooth oak Health Assessment Indicator System to evaluate sample data, the results show that the level health index of small class level health index plots exist significant linear relationship, the regression equation was Y = 0.838 X-? 0.079 (F = 44.954, R = 0.785, P lt; 0.0001). Therefore, the health evaluation index system with small class level evaluation of community health. (5) has collected Huoditang forest region in 1958, 1987, 2004 Forest Resource Inventory Data, Sharptooth Oak in small classes in more than 5 percent as the object of study, evaluation of different periods Sharptooth oak forest health condition, results: 1958 sharptooth oak forest health, small class accounted for more than its sub-health overall proportion of 86.7%. Followed in 1987, accounted for 36.4% of its sub-health more small classes, small class proportion of more than 2004 sub-health at least 26.4%.
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