The Research Of Outturn Percentage Of Timber Species In Fuzhou State-owned Forest Farm Fir Forest

According to stand average diameter at breast height,average tree height,plantation age,stand density,site quality and distribution of water-holding capacity among different factors such as area,national forest farm from fuzhou in the cutting area of nearly 15 years to select the typical Chinese fir forest,based on survey data of cutting area,according to the principle of three standard deviations to the stand average diameter at breast height,average tree height were screened,collected 501 pieces of correlative production related data.Using SPSS software analysis stand each planted out material rate and stand factors,the correlation coefficient between the results show that the average diameter at breast height,average tree height and forest specification material,economic,waste and commodity rate of the material was highly correlated between stand density and fuelwood material rate is highly positive correlation between Chinese fir stand in different distribution regions and the influence of the site quality of planted out material rate are very significant.For forest planted out material rate the influence of the size of the stand average diameter at breast height,average tree height and stand density,overall,with the increase of stand average diameter at breast height,average tree height,specifications material,economic and commodity rate of the material gradually rise,the specification of material,fuelwood and waste the material rate is gradually decreased;With the increase of stand density,economic material and body material of the material rate gradually decreased,fuelwood and waste material yield increase gradually,the specification of material and product material material yield basically maintain steady state.In this paper,through analyzing the stand between each planted out material rate and stand factors,based on the stand average diameter at breast height of forest stand one-dimensional timber-produced rate model,based on the average tree height of forest stand average diameter at breast height and two-dimensional timber-produced rate model,based on a lot of forest stand factors of forest multiple planted out material rate model,to the sum of squared residuals RSS and adjustment coefficient R2 to judge the fitting precision of regression model,to meet the requirements of the regression model fitting precision further according to the total relative error(RS),average relative error(E),average relative error of the absolute value(RMA)the forecast precision P and F test suitability test indexes such as size,select the most optimal planted out material rate model After the model through the applicability test,in order to ensure the material yield of each material in the stand is equal to the sum of the theoretical value of 100%,according to the chosen one yuan,binary,diverse planted out material rate equation calculation rate of the planted a material modification,make it meet the requirements of the theory,which planted the material rate multivariate regression equation calculation of the specifications of the material,economic,fuelwood and commodity rate of the material can be don't have to be revised,can be directly compiled into a table.