Study On Constructing Of Yield Table For Pinus Massoniana Plantation In Anhui Province

Site index and yield tables which are basic files for forest management and estimating stand growth,volume yield etc.has always been a hot point in research by scholars.Pinus massoniana is one of important timber species with fast-growing in Anhui province.This study based on 318 plots of Pinus massoniana plantations in ten cities including Lu'an,An'qing,Huangshan,Xuancheng,etc.By principles of forest measuration and SPSS 18.0,many forest factors regression models have been construced to compile yield table of Pinus massoniana in Anhui for adapting new situations of forestry management.The main conclusions are as follows:(1)With eleven growth equations,which dominant trees as dependent variables and ages as independent variables,a guide curve has been found by comparing coefficients of determination and residual sum of squares.The guide curve equation is Ht=34.4053·e-5.5454·A-0.5820The stand age is determined to be 30 years old,and the class interval is 2 metres.The site index of Pinus massoniana plantations in Anhui is constructed.(2)With Korf equation,Mitscherlich equation,Gompertz equation,Richards equation as height and DBH growth equations,H = 3.3431 · SI0.6657 · e-1.7825e-0.0649·Dg?13.7945 ·SI0.8180·e-3.1105·e-0.0148·A have been found by comparing coefficients of determination and residual sum of squares.And the equation of plant population per hectare is N = 18103.0973 · Dg-1.2553 · H0.3800The equation of volume per hectare is M = 0.00171 · Dg1.47076 · H0.92457· N 0.71905With these equations,the empitical yield table of Pinus massoniana plantations in Anhui is constructed.(3)With three parameter Weibull distribution as plots' diameter distribution models,parameter a,parameter b and parameter c have been found to estimate the number of trees of every diameter in every plot.a = 0.0207 · Dg2-0.1724 · Dg + 4.5404 b =-1.0439 · a + 1.0677 · Dg-0.4651 c = 1.0919 · cvx-1.0282(4)Through the x2 test,the real plot agreement rate is 92.5%,and the simulated plot agreement rate is 87.5%,which represents three parameter Weibull distribution fitted well forPinus massoniana plantation in Anhui.