| Based upon the Korf growth equation, stand growth and yield models for Larch (Larix olgensis Henry) Plantations were developed by using data set from16 permanent plots, 16 temporary plots and stem analysis in Mudanjiang area of Heilongjiang province.Self-thinning procedure was found be related to site and initial density by analyzing ultimate self-thinning line of larch plantations. The trend of stand density (SDI-t curve) is sigmoid. The better the site condition are, the higher the mortality rate is. The faster the SDI increasing as age increases and the stand early develops into competition state.In addition, using re-parameterization method, site index and SDI were introduced into Korf growth equation in order to develop stand basal area growth model. In the model, the asymptotic parameter is mainly affected by site conditions, while curve shape parameter and growth rate parameter are related to stand density and site conditions. The whole stand model system was set up for Larch plantation, which was composed of 5 models mentioned as follow and models were compatible each other: 1) stand ultimate self-thinning line and definition of SDI; 1) prediction model for trend of stand density index (SDI); 3) predicting model of height-diameter curve; 4) stand basal area growth model; 5) Schumacher's stand yield model. Using this model system, development of quadratic mean diameter (DBH), mean height (H), the number of surviving trees per hectare (N), stand basal area (G), and stand volume (M) can be simulated for various levels of initial density and site. The stand growth and yield models developed in this paper may be used to simulate stand dynamic development procedure. It provides better base for further developing stand management model and rational management of Larch plantation.
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