| Areas of this study are located in 3 Forestry Farms (Xixia, Erlonghe, Wanghanan) of Forestry Bureau, Liupan Mountain region of Ningxia province in the Northwest China. The Liupan Mountain is a typical representative area of water-limited forest ecosystem sited and is very important conservation forests for water resources in the Northwest China.The purposes of this study is to seek the characteristics of stand structure and dynamics of typical forests and the growing rules of main tree species in this area. The data of this study composed by 4 types: self sampling data gained by field plots survey, collected data of permenam sampling plots of the national monitoring system between 2004 and 2005. Data of stem analysis get from the dominant trees in self sampling plots, The monthly meteorological data continually from 1971 to 2005. Three typical forests with four main species are selected for this study, they are Larix prinncipis-rupprechtii plantation, the natural mixed forest of Tilia spp. and Quercus liaotungensis, mixed forest of and natural mixed forest with dominant species of Betula platyphylla.The main contents of this study are as follows:1. The stand spacial structure of horizontal and vertical, the biodiversity in three typical forests;2. Growth of four main species;3. The effect of climate factors on tree growth by methods of cross corr(?)lation and response surface function;4. Diameter increment and stem number dynamic analysis in three typical forest;5. Simulation experiments for natural secondary forest.The main results are as follows:1. The study in stand structure show that Larix prinncipis-rupprechtii plantation forest stand tree speceis diversity and natural regeneration rate are lower conpare to the secondary forests, spatial distribution of trees are uniform and distinct normal stem number-diameter distribution, and stand vertical structure is simple with one canopy layer. The study in stand structure show...
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