The Introduction Of WWPB Model And Application Research To Pinus Tabulaeformis Damaged By Dendroctonus Valens In Shanxi

Forest Vegetation System(FVS)has been introduced from the United States.Our study focused on WWPB component as the extension of FVS.FVS forecast the stand growth based on actual conditions and a set of the growth equation.WWPB model can simulate the beetle behavior,dispersal,and reproduction in stands.Pinus tabulaeformis was the site tree in Lingkongshan forest farm.The paper showed the diffusion behavior of Dendroctonus valen in stands.The main contents of this paper, including:1.Study on FVS:FVS is composed of preprocessor,data transition,SUPPOSE,growth and yield models,postprocessor,Stand Visualization System,Keywords and extension,etc.and growth and yield model is most important part.Growth and yield model included diameter increment model, height growth model,mortality model,tree crown model and volume model.2.Study on WWPB model:The West wide Pine Beetle Model(WWPB model)is a multi-stand beetle impact model designed as an extension to the USDA Forest Service's Forest Vegetation Simulator (FVS).This simulation contained 25 stands P.tabulaeformis.The conclusion is:Suffer heavier in the area next to the road;suffer heavier in the near stand to the origin stand;suffer heavier in the base of the mountain;human activities also affect the dispersal of Dendroctonus valens.3.Study on SVS:The Stand Visualization System(SVS)generates images depicting stand conditions represented by a list of individual stand components,e.g.,trees,shrubs,and down material.The images produced by SVS,while somewhat abstract,provide a readily understood representation of stand conditions and help communicate silvicultural treatments and forest management.4.GIS applied in the FVS system:FVS provides a powerful data output function.FVS simulation results can be directly stored in a common format database,which provided the conversion interface with the other system,sharing the information expediently.FVS-generated database file can be read directly from the ArcGIS software,and the simulation results are reflected in the form of visual graphics in GIS,so achieving the combination with geographic information systems.5.Supplementary research of FVS:A new data conversion tool developed which named DFFC(Data for FVS in China).This tool can change data format from Raw Data to the FVS-Readable format. The Conversion included:1.The tree information of each stand transformed separately.2.All the transformed data input into a single file.The data files can be very easily imported to the database for FVS...