Study On Structure-Function Model Of Based On Cumminghamia Lanceolatam Greenlab

The size and structure of the crown determines the growth vitality and productivity of trees.It is also the main part of a series of physiological activities such as photosynthesis,respiration and transpiration,which makes the crown plays a crucial role in various benefits of trees(such as social benefits and ecological effects).On the basis of Greenlab structure-function model,the relevant morphological structure model is established,which provides the basis for realizing the visualization of trees,understanding the configuration of tree canopy,and selecting appropriate forest management measures.This paper takes Fujian Jiangle national Cumminghamia Lanceolatam forest(artificial forest)as research object.Based on collection and observation of early stage parse tree,leaf and branch factor data I establish Cumminghamia Lanceolatam area model.I analyze vertical distribution of primary and secondary branches and build quantity distribution model of Cumminghamia Lanceolatam primary and secondary branches,and also build dynamic model based on diameter and length of Cumminghamia Lanceolatam primary branches by coupling Cumminghamia Lanceolatam primary branches length and basal diameter model with tree height and DBH sub-model.The results show that:(1)By comparing the regression models of leaf area-leaf shape attributes and leaf area-leaf dry weight of Cumminghamia Lanceolatam,the optimal model of leaf area of Cumminghamia Lanceolatam is leaf area-leaf dry weight regression model,that is,leaf area is proportional to leaf dry weight..The comparison of three methods for calculating the specific leaf area shows that the optimal method for calculating the specific leaf area is the ratio estimation method,and the specific leaf area of Cumminghamia Lanceolatam is 28.3648 cm2/g.(2)In this study,the general linear regression model,Poisson regression model and negative binomial regression model were used to establish the forecasting model of the number of first and second branches of Cumminghamia Lanceolatam by using the method of total sub-regression.Finally,it was concluded that the model based on the negative binomial regression model was the best one.According to the optimal model,the correlation of the number of first branches was the greatest.The first branch diameter was proportional to the factor.The number of secondary branches and the percentage of crown length were inversely proportional to the ratio of height to diameter,and directly proportional to crown width and tree height.(3)Based on the DBH sub-model,the height sub-model,the first branch length and the base diameter sub-model of Cumminghamia Lanceolatam,the dynamic model of the first branch length and base diameter varying with age was obtained by coupling simultaneous equations.After verification,the dynamic model has high accuracy in mature Cumminghamia Lanceolatam,and poor predictability in the growth and development stage of Cumminghamia Lanceolatam.