Abstract:Based on the investigation in 7 research regions of 3 zones in Shaanxi Province, the biomass and productivity of P. tabulaeformis plantations were studied, The research materials of 295 felled trees in 55 sample plots became the basis of the establishment of the estimation equations for the biomass of each organ of P. tabulaeformis. The correlation coefficients of most equations were more than 0.90, and the precision was more than 90% (95% reliable level). The standing crops, average net primary production. current net primary production and dry-matter production efficiency of leaves in different climatic zones were studied and compared. The results show that the stands studied in to Qinling Mountains are superior to those in Northern Shaanxi, the main production indices of stands in the subtropical zone differ insignificantly with those in the south temperate zone, but were higher than those in the temperate zone. There is a decreasing trend in the proportion of stem (with bark) biomass from south to north, and a reverse trend in the biomass of the tree crown. The kinds of plant species under the studied stands were found not rich, their biomass accounting for approximately 1% of whole biomass of the community. The litter biomass differs very much among the studied areas and the proportion of duff biomass decreases from south to north. By comparing P. tabulaeformis plantations in Shaanxi Province with those in other provinces, we could see that the productivity level was higher in former.