Visualization Simulation And Analysis Of Afforestation Design Scheme

Forest ecosystem is a complex giant system and has a long growth cycle,which makes the design results of afforestation schemes to be showed about ten years or decades and takes lots of complexities and challenges to forestry research and forest management.With the development of computer,artificial intelligence,visualization and other technologies,and with the integration of multi-disciplinaries,some new research directions such as virtual forest environment are generated in the forestry field.With years of development,virtual forest environment has gradually been recognized as a potentially auxiliary tool for forest growth analysis,forest resource management and decision support.Based on the principle of reforestation shemes design and the theories of near-natural forest management,combined with three dimensional visualization technology,geographic information system,decision support system and virtual plant technology,a three dimensional assisted reforestation schemes design and analysis system to be developed.The system achieved intelligent recommendation and interactive design of reforestation schemes,and showed the effects of afforestation in a virtual geographic environment in an intuitive way.In this paper,using the spatial structure index and canopy density analysed the stand structure built according to afforestation schemes,which provides decision support for afforestation shemes adjustment and forest near-natural transformation.The main contents and results were as follows:(1)Afforestation rules set and cases set bulit.The suitable site conditions(such as geomorphology,altitude,slope,aspect)and afforestation pattern for main afforestation tree species of the Fujian province was collected and summarizd,the 110 rules of foremost afforestation tree species were finally built.And according to the forest resource inventory data of the state-owned forest of Zhangping City,Fujian province in 2008 year,the 2117 afforestation cases were finally built.(2)Formal representation and reasoning of afforestation knowledge.Based on produciton representation method,the inference mechanism was designed and implemented based on rule knowledge or case knowledge,which achieved intelligent recommendation of the reforestation schemes.(3)Three dimensional visualization of afforestation schemes.According to the designed reforestation schemes,the visualization technology and vitual plant technology were used to build virtual forest scene in a virtual geographic environment,which achieved 3D visualization of reforestation schemes.(4)The uniform angle index analysis method of spatial distribution pattern based on voronoi diagram.Based on spatial structure theories and by simulating different distributed types of stand spatial structure,the confidence interval of uniform angle index for randomly distributed was determined,which provides technical support for analysis of spatial structure rationality of reforestation schemes and near-natural transformation of the forest.(5)Estimation method of the canopy density.Based on the shadow graph theory in three dimensional visualization technology,the estimation method of canopy density was proposed under the virtual three dimensional environment,which provides decision support for the selective intensity reasonable control.(6)Comparison and analysis between afforestation schemes.To promote the near-nature transformation of forest,the more appropriate reforestation schemes to be drawed through comparative and analysis of spatial structure and canopy density change of the mixed forest of Fir and Pine under different reforestation schemes and selective cutting intensities conditions.