The Study Of Simulation And Visualization Of Self-adapting Chinese Fir Stand Structure

With the fast development of information technology and the perfection of computer technology, Visualization technology is widely used in every field. It becomes increasingly hot in forestry by reason of breakthrough the limitation of time and space in forestry research and forestry production. The establishment of Virtual Forest Environments makes forestry research and forestry management more convenient, more directviewing, and more efficient. But visualization requires very detailed data source, many factors need to be collected in stand visualization, this makes researches more difficult. To build self-adapting model that can fit various data source, make the way of data procurement more flexible, is also a hot topic in stand visualization studies.This study deeply discusses present theory of stand visualization, summarizes its trait., stand structure adaptive approach has been proposed to find out a mechanism that suit every conventional stand structure data. On the basis of existing theoretical research, factors required in stand visualization have been extracted, they are stand terrain, tree coordinate, tree diameter, tree height and canopy breadth. According to the degree of detail of these factors, conventional data were classified into four class, simulation model were established for every class. On the base of stand structure regulation, calculate tree coordinate depend upon directional distribution of trees, calculate tree diameter depend upon distillation function of diameter, calculate tree height and canopy breadth depend upon correlativity function between diameter and other factors. According to APA(Area Potentially Available), the factors were allocated into every single tree by a non-weighted way, to achieve the process produce detailed stand structure data by conventional data source such as stock map and subplot cruising data. Virtual Forest Environments was established at stand scale, tree terrain was established by hypsogram exported from DEM data, Chinese fir 3D model were established by Create Tree System. Using C# programming language and MOGRE open source engines, author accomplishes the programming of Stand Structure Visualization Module of Quick Stand System, and this provides a good foundation for Stand Growth Module and Forest Management Module.Take the Chinese fir artificial stand in Huangfengqiao Forest Farm, Hunan, as the study area, the practice of Chinese fir stand structure visualization has been carried out. The results showed that the simulated stand had the same distribution characteristics as reality stand. This study is a new try of stand structure visualization approach, provides a new train of thought for further research.Paper was supported by forestry research & special public service sectors "stand structure and growth simulation studies (201104028)" and the central level, scientific research institutes for basic R & D special fund business "Chinese Fir stand structure and growth simulation and visualization studies(IFRIT200904)".