The Study Of Endangered Mechanism About The Threatened Plants Of Pinus Sect.Strobus In China

The main purpose of this study was looking for endangered mechanism of threatened plants of Pinus Sect.Strobus in China from the climate and ecology and making meaningful recommendations for protecting endangered plants of Pinus Sect.Strobus.This thesis collected geographical distribution data and meteorological data of Pinus Sect.Strobus. ArcGIS and SPSS software were used to analyze the characteristics of geographical distribution and climate. Using the coefficient of variation compared, regression analysis and other data processing methods, endangered mechanism of climate about the threatened plants of Pinus Sect.Strobus in China was found from the analysis of climatic factors of Pinus Sect.Strobus plants’distribution areas.Three distribution areas can be divided in China, northeastern distribution area, south of the Qinling Huaihe distribution and Himalayan distribution area. The habitats in south of the Qinling Huaihe show high temperature, high humidity, short illumination time; Northeast and Himalayan habitat show low temperature, medium humidity, long illumination time. Annual temperature, mean temperature in January and minimum temperature are the mian climatic factors affecting geographical distribution of Pinus Sect.Strobus through the coefficient of variation compared. Regression analysis between altitude lower limit and climatic factors of Pinus Sect.Strobus in the south of Qinling Huaihe River region make the main climatic factors affecting geographical distribution of Pinus Sect.Strobus clear.Pinus aquamata and Pdabeshanensis which are extremely endangered plants were surveyed in the field and were analysed with ecological approaches. There are four main results. The first, there are no seedings and young trees in the population of P.aquamata and there are a lot of seedings and very high death rate of seeding in the population of Pdabeshanensis. The second, arborous layer in the community of P.aquamata is broken and has a few kinds of plants; and arborous and shrub layer in the community of P.dabeshanensis have a lot of species. The third, the positive and indistinctive correlativity is showed between P.aquamata and the other plants of the community; the prominent and positive correlativity is showed between P.dabeshanensis and P. taiwanensis、Quercus serrata, meanwhile the prominent and negative correlativity is showed between P.dabeshanensis and Stewartia sinensis. The forth, there is most drastic competitiveness from P.aquamata and P.yunnanensis for P.aquamata; and there is most drastic competitiveness from P. taiwanensis, Quercus serrata and Fagus engleriana.