| In this paper, we do some research about indicators of individual tree competition, based on analysis of space-related. to study the competitiveness of the two types of indicators of the buffer zone, they are basal area of the buffer zone rating BBR and basal area of the buffer zone distance rating BBDR, and its correlation with the diameter at breast height have reached a significant level. thus, it can achieve better modeling results by using Basal area of the buffer zone rating BBR and Basal area of the buffer zone distance rating BBDR as the competitiveness of individual tree growth indicators.Based on the research of Competition indicators, taking the average forest area of Thiessen Polygon as stand density indexes, and separately taking basal area of the buffer zone rating BBR and basal area of the buffer zone distance rating BBDR as Indicators of individual tree competition, established tow models of the 5:3:1 by artificial neural network, Single tree growth model of basal area of the buffer zone rating BBRnet and Single tree growth model of basal area of the buffer zone distance rating BDBRnet . Tested the Accuracy of these two models .The results showed that the length of the interval tree BBR model and single tree growth model BDBR significantly affect the accuracy of the model forecasts the longer interval, the lower the accuracy of the model. In the 6-year interval period, the two fitting models have higher accuracy.Proposed Buffer-type competition indicators, making individual tree growth models focused only on the time related research previously, and now have begun to enter the space and time and space-related research, so that simulation of forest growth forecast to taking time and space factors into account ,make forest management more scientific and rational decision-making. At the same time, it has great significance and application value combining stand growth model with GIS, GPS technology, bio-geographical statistical.
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