Reaserch On Simulation Technology Of The Forest Growth Management Models In North Hebei Mountain Area

The rapid development of artificial forest to some extent can alleviate and meet the needs of human, and it has slowed down the damage speed of natural forest, and has played an important role in the protection of the ecological environment. But due to the lack of scientific theoretical guidance and practical sustainable management technology for a long time, too much attention, and the pursuit of short-term productivity and economic benefits, despise species, site conditions, deviated from the inherent law of the survival and development of the forest, resulting in artificial forest area expansion and quality was significantly decreased the contradiction. Domestic and foreign research and practice prove that, near-natural forest management is the first choice to solve the low quality of artificial forest, the bad ecological benefit, and is the inevitable trend of modern forestry development.Ji Bei is the key point for the formation of land ecological environment security system with forest and vegetation cover as a main body such as Beijing-Tianjin desertification governance, returning farmland to forest land, establishing the “Three North” shelterbelt, and Taihang Mountain greening, and the study on Ji Bei informatization is the key step of the forestry informatization construction in our country. In this paper, through analysis of the forest stand data by means of related computer technology and data analysis function, appropriate man-made forest operation technology system for Ji Bei has established, improves the simplicity and operability of plantation tending, accelerates shift from man-made forest towards near-natural forest, speeds up near-natural idea promotion in Ji Bei, and strengthens plantation ecological, economic and social benefits.The main work is as follows:1.With near-nature management theory as instruction, put forward the model of forest competitive advantage analysis based on k-means clustering. Calculate Hegyi competition index, and classify forest stand, find out the optimal competitive potential range, and analyze the accumulation growing dominance degree of forest trees and then find the competitive pressure index range which is the most beneficial to improve total forest accumulation, to provide data and technical system supports for intermediate cutting choice and update.2. Self-thinning model suitable for Hebei North mountainous area was established by means of BP neural network; based on competition analysis and classification, conduct thinning simulation to sample area in three different ways as per competition pressure index, aggregation index, the anticompetitive pressure index; find out the effect on forest stand of different thinning programs with different thinning intensity and different thinning modes simulated and calculated by computer software, and determine the most suitable formulation method of thinning program.3. DBH growth equation model was set up with improved genetic algorithm. According to the initial tree DBH, age and initial density and so on, appropriate man-made forest growth model for Northern Hebei mountainous area has Established, after competition analysis and classification, and thinning choice, simulate the calculation of DBH n years later with growth equation DBH, and simulate forest stand accumulated harvest in application of accumulation calculation model.4. On the basis of competitive analysis and classification, choice of thinning, and simulated harvest of forest stand accumulation, forest management system was designed and realized.