Abstract: Logarithmic regression equations of leaf biomass (W_L), branch biomass (W_B), trunk biomass (W_T) and root biomass (W_R) to the product of breast diameter (D) and hight (H) D²H, have been worked out respectively for the artificial ecosystem of Michelia macclurei var. sublanea. The biomass is 264.22ton.ha^-1 and the net production is 26.06 ton穐a^-1穣r?^-1 for the stand of 46 years in transition zone between southern subtropics and northern tropics. Owing the net production is still higher than the mean productivity, it should be a productive ecosystem. Michellia macclurei var. sublanea is a good spceies for afforestation in Southern Guangxi, which has a great productive potentiality.

Key words: West of northeast China, Sandy desertification region, Vegetation, Classification