A Analysis Of Spatial Distribution Pattern Of Larix Gmelinii Natural Forest In Da Hinggan Mountains

L. gmelinii is dominant species in Da Hinggan Mountains, whether L. gmelinii stand to be health or not has a significant effect on forest ecological system. Because of reasonable spatial distribution of stand is the prerequisite and basis of forest health, so formulating near natural management modes by research spatial distribution of natural L.gmelinii forest to conduct forest management is expecially important.This study looks mainly at gaps in natural L. gmelinii forest and is based on data from records collected at the Pangu Farm, Tahe Forest Bureau, Da Hinggan Mountains in July2011. Our research looked at the spatial distribution patterns of natural L. gmelinii forests by analyzing gaps in plots. We selected suitable class parameters at a landscape scale and combined with the state of tree spatial distribution pattern along with the competition index and mingling of stand, the result show that:The mingling index of stand renders the first increase and then decrease trend and achieved maximizing in half-mature forest. The competition index represents decreasing trend during the process of forest develop from young growth to half-mature forest. During forest develop from Nearmature forest to over mature forest the competition index begin increase. During the development process L. gmelinii represent aggregative distribution; The class area index achieved maximizing in half-mature forest. On the effect of the state of forest distribution and lateral growth of forest the AWMSI index and MNN index render first decrease and then increase trend.The competition index declined with the level of fire disturbance declined in stands which suffered varied intensity fire disturbed, Mild disturbance of forest fires had significantly improved mingling of stand. The results show stands which suffered moderate fire disturbance retain only a small amount of medium and large diameter live trees of L. gmelinii. the distance between the patches was the shortest of the patches themselves are very complicated since moderately intense fire leaves a significant and irregular accumulation of gaps within any particular plot; The research plot, in a stand that was burned with low intensity fire, retained most of its L. gmelinii, The low intensity burn area had the smallest gap patches. The shape of these small gap patches was the most uniform and the separation between the gap patches was the largest of the three phases; The unburned plot with no known history of fire disturbance included a complex patchwork or network of gaps of different sizes. Because fires burn with different levels of intensity, the undergrowth was transformed into gap patches. The spatial distribution pattern had changed with fire distribution.This study comprehensive response spatial distribution of natural L. gmelinii stand by research gaps that once not taken seriously in stand and according to different spatial distribution pattern this study designed a primary project to manage forest. This paper has an important significance for adjustment of forest spatial structure and promoting the healthy development of forest.