Three-dimensional Visualization Simulation Interaction With Light Environment For Mongolian Scots Pine In Plantation

This study was performed in Mongolian scots pine (Pinus sylvestris L. var. mongolica Litvin) plantations in Maoershan experiment forest centre of Northeast forestry university. Based on stem and branch analysis, data were collected from53sample trees in15plots with different age, site condition and density in2002(7) and2003(8). This study developed the crown static models and dynamic growth models of Mongolian scots pine plantations. The three-dimensional visualization simulation system of Mongolian scots pine was established on the developing platform of VC++6.0language and OpenGL. The three-dimensional visualization simulation of Mongolian scots pine morphological structure based on actual measurement data and growth model was realized in this paper.The contents of this paper were as follows:1In this paper, the canopy photosynthetic characteristics of Mongolian scots pine was studied. Results show that needles at different positions of the crown have different light response for their net photosynthetic rate as a single peak curve whose peak appear in around noon and the upper layer greater than middle greater than the lower. It suggests that different light dynamic responses of needles at different positions be related to micro-light environment to which needles acclimated in a long time. Diurnal variation of Pn showed a single peak. It had significantly positive correlation with stomatal conduction (Cond), transpiration rate (Tr)(at0.01level) and photosynthetically active radiation (PAR)(at0.05level), and significantly negative correlation with the intercellular CO2concentration (Ci)(at0.05level). Photosynthetic rate model of Mongolian scots pine at leaf-level was built considering the impact of photosynthetically active radiation,temperature and CO2concentration.2Morphological structure model and the canopy model of Mongolian scots pine were established in this paper. The results showed that the models only with branch angle model and each round of the branches of trees model was not ideal.3Through definition related variable factors mongolica plantations structures, class, function and variables, loading the measured data files and reading the related field to trees structures, and then after initialization and render to complete the drawing of trees morphological structure, realized the mongolica plantations in the three dimensional simulation.