陕西省不同气候区域油松人工林生物量和生产力的比较研究

COMPARARIVE STUDIES ON BIOMASS AND PRODUCTIVITY OF PINUS TABULAEFORMIS PLANTATIONS IN DIFFERENT CLIMATIC ZONES IN SHAANXI PROVINCE

本文初步研究了陕西省3个气候区域内7个地区的油松人工林生物量和生产力。根据55块标准地的295株伐倒木资料,建立了油松各器官生物量的估计方程。经研究比较不同区域油松人工林的生物量、年平均净初级生产量、现实生产量和叶片的干物质生产效率,结果表明,秦岭山地的油松林一般优于陕西北部的油松林,北亚热带和暖温带的汕松林各项指标相差不大。但明显高于温带油松林。树干(带皮)生物量比例从南向北逐渐降低,树冠生物量比例从南向北逐渐增大。各调查区油松林分的林下植物种类不多,生物量约占群落总生物量的1%。林地凋落物重量在各地区之间差异很大,未分解层比例从南向北逐渐减小。经比较发现,陕西省大部分地区的油松人工林具有较高的生产力水平。

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 biota ass 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 pro vinces, we could see that the productivity level was higher in former.