Abstract:

In order to establish the biomass forecast equation and solve cutting age of pulpwood stand for Masson pine (Pinus massoniana Lamb.)plantation,forecast equations of various stem economic biomass with and without bark were established with 265 diameter grade biomass sample tree in this paper,forecast problems of various stem economic biomass of pulpwood stand were resolved.According to the differnces in site index and cultivation measures,15 silviculture patterns of pulpwood stand were given for each site index.The stand quantitative,technical and economic mature ages of various silviculture patterns were calculated,then optimum cutting age of various site index were determined,it was 12～15 years shorter than cutting age being used,and it's IRR was raised 4.22%～9.47%.The relations between cutting age and site,silvicultural condition(planting density,thinning),economic condition were studied.The results showed that quantitative and economic mature ages reduce with the raising of site index,the quantitative mature ages reduce with planting density increase,the quantitative and economic mature ages postpone with thinning times increase.The economic mature age reduce with discount rate increase,while discount rate was raised 3% the economic mature age reduce about 2 years,otherwise,the economic mature age put off about 1～2 years.

Key words: Masson pine, Pulpwood, Cutting age, Mature age