Study Of Forest Stand Spatial Structure And Competition Based On Three-Dimensional Simulation Techniquee

In this paper, use topographic maps, aerial photo, forest form map of Jiufeng National Forest Park, built the 3D models of the whole study area by ArcGIS and Google Sketchup sofrwares. Choose two typical stands of the area—Platycladus orientalis stand and Quercus variabilis Blume stand to do fields investigation. Use the investigation data to do the 3D stands model, simulate terrain stand the internal structure and external environment. Analysis stands spatial structure by calculating four indexes: mingling, neighborhood comparison, competition and angle, and research optimization and adjustment program. Use the 3D stand models to simulate optimization program.Simulate 3D terrain by building TIN, use the Sketchup to build the modle of four species: Platycladus orientalis,Quercus variabilis Blume, Piuns tabulaeformis and Acer elegantulum. The model of the whole study area was built by point factor and the model could check the vegetation, terrain and species. The 3D stand model were built by using Multipatch geometry type. Every tree of the stand model included its own attributes and spatial location.Calculate the spatial structure of Platycladus orientalis stand and Quercus variabilis Blume stand and showed the result that isolation was low, angle index was large and competition was intense in both two stands. Interspecific competition was more conspicuous in Platycladus orientalis stand and intraspecific competition was more conspicuous in Quercus variabilis Blume stand. Both stands were not well indicated by angle index which was not equal on both sides when it valued in 0.5. After a 10% scale distribution, the value were equal on bosh side of 0.5, mingling value were grown and completion were decreased. Made 3D models for four species of two stands, and used Geodatabase to built models of stands. Simulate the optimization programs result to provide advises for forestry management.