Research Stand Structure And On Growth Of Cyclobalanopsis Glauca Secondary Forest

Cyclobalanopsis glauca is an important species of broad-leaved evergreen forests which belongs to Fagaceae.It is widespread and have a high ecological status and comprehensive value.AS a precious native species,we focus on the natural secondary Cyclobalanopsis glauca forest to research the characteristics of it’s structure and growth.we can provide theoretical basis and reference for how to scientifically manage the forest and accurately promote the quality of the natural secondary Cyclobalanopsis glauca forestThis article comes from the project of "research and demonstration on key techniques of improving and increasing the quality in the Phoebe bournei and Cyclobalanopsis Glauca forest(201504301)".Taking experiment station of Lutou forest farm as base,we use the plot and the data of the parse tree to figure out the basic structure and the characteristics of Cyclobalanopsis glauca forest stand and also analyze its growth process of each factor of tree measuring.Meanwhile,a growth model of the single wood and the basal area of Cyclobalanopsis glauca forest stand has been built based on the data of the parse tree.The main research and results are as follows:(1)The important value of each wood in plot were calculated,in order to figure out the composition of tree species.The I layer dominant species is Cyclobalanopsis,Glauca,The Ⅱ layer dominant species is Rhododendron simsii Planch.Use the histogram to get the forest’s age,the result show that I layer is the young or middle-aged Cyclobalanopsis Glauca forest,the II layer is the middle-aged Rhododendron simsii Planch forest.We partition layer of forest and use the histogram to count and analyze the age distribution of secondary Cyclobalanopsis glauca forest The diameter and height structure of each layer would be researched,and use multiple equation and function to match the DBH and height data.It shows that the DBH model follow Weibull distribution and the optimal model of diameter-height curve is H=3.0499×D0’45332.Based on four different structure units of forest to analyze the experimental form factor and breast height form factor of Cyclobalanopsis glauca.It turned out that,the form of Cyclobalanopsis glauca objective tree which have two or three neighboring Cyclobalanopsis glauca trees was better than other two cases.(2)The research for growth process of natural secondary Cyclobalanopsis glauca forest,including the tree diameter,height and volume.The diameter grew slowly during the first 5 years,and then grew faster.The growth rate reached the maximum at the year 15,then it came down,the maximum growth rate is 6.7%.The average and current annual increment reached the maximum at the year 35 and 52.The growth rhythm of height was consistent with the diameter,The growth rate reached the maximum at the year 5,and it was 8.5%.The average and current annual increment reached the maximum at the year 35 and 51.It’s growth rate reached the maximum at the 5 year.The volume grew slowly during the first 20 years,and the growth rate reached the maximum at the 35 years,and it was 8.6%.The current annual increment reached the maximum at the year 46.The annual and mean volume growth has intersect at the age of 68.At this point,the Cyclobalanopsis glauca attained the quantity mature.(3)Research in growth model of single wood and standing forest of Cyclobalanopsis glauca.Five different theoretical equation were used to describe the growth process of diameter,tree height and volume,and built the single wood model of Cyclobalanopsis glauca.The highest accuracy of simulation on diameter,tree height was Richards theoretical equation,the model is D=48.7276(1-e-0.0312t)1.7754 and H=17.8577(1-e-0.0308t)1.0582.The Gompertz theoretical equation which is V=0.3826e-6.1267e-0.0689t worked best on volume.we chose the age and stand density index as argument,based on the equation of Richards theory,to build the growth model of Cyclobalanopsis glauca standing forest.The model which had a better result,and it’s simulation precision was 0.727.So this model met the growth of Cyclobalanopsis glauca standing forest.The model is:...