Study Of Forest Health Assessment In Beijing Area

Forest health study has been a focus issue in forestry nowadays, forest health assessment is very important to security of ecological environment in Beijing, but we do not have a complete and unified assessment system for operation. This paper proposed Community Structure-Diversity Index Model with normal Ecological indicators, assessed 39 plots from community structure and biodiversity scale in Badaling, Xishan, Xiaolongmen and Miaofengshan Forest Center. In order to verify the feasibility of CSDI model, this paper used factor analysis to assess the same plots more objectively with 16 indicators, such as average height, average diameter at breast height, biodiversity index. The results showed that the two methods came to the conclusion consistently, reflected the health of plots objectively:1.Nature forests are more healthy than planted forests, nature Juglans mandshurica forest, Betula dahurica forest, Tilia mandshurica forest in Badaling Forest Center and nature Quercus liaotungensis forest, deciduous broad-leaved mixed forest in Xiaolongmen Forest Center are have high health level, reflect the advantages of nature forests in species and community structure. But it is possible for planted forests to reach health, like Pinus tabulaeformis forest in Badaling.2. Nature forests are healthy in Badaling, but planted forests'health situation is not ideal except Pinus tabulaeformis forest, so transformation is needed. All of the plots in Xishan and Miaofengshan are planted forests, although have not reached the healthy degree, they are in gradually stable trend after 50 years of tending. Natural vegetation in Xiaolongmen and adjacent areas can be used as the reference standard of health assessment for they are preserved well, have rational structure and rich species.