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对株行距分别为2m×4m、3m×4m、4m×4m、5m×4m、6m×4m的5种林分密度银中杨人工林的生物量及营养元素吸收积累量进行了测定,同时分析探讨了不同林分密度银中杨的叶面积．光能利用率。研究结果表明,8年生银中杨人工林生物量为45．8～89．1t／hm2；林分生物量与林分密度正相关,林分密度不同则生物量在各器官的分布比例不同,林分密度大的林分干材所占的比例较林分密度小的高。平均净生长量为6．6～13．1t／（hm2·a），干材的生产力最高,叶次之。叶面积指数均在2．4以上,高达4．2,与林分密度呈正相关。银中杨每生产1t生物量需从土壤中吸收22．6kg营养元素；叶片中营养元素积累的速率明显高于其它器官,枝次之,枯枝落叶在林分养分循环中起重要作用。
The biomass and nutrient absorption and accumulation of five kinds of plantation density-provenance plantations of 2m × 4m, 3m × 4m, 4m × 4m, 5m × 4m and 6m × 4m were measured at the same time The leaf area of Populus euphratica with different stand density was discussed. Light energy utilization. The results showed that the biomass of the 8-year-old Populus simonii plantation was 45.8-89.1 t / hm2. The stand biomass was positively correlated with the stand density. The biomass distribution in different organs was different with different stand densities, Stands of forest stand density proportion of forest stand density than high. The average net growth of 6.6 ~ 13.1t / (hm2 · a), the highest productivity of dried wood, leaf times. Leaf area index were above 2.4, up to 4.2, and the stand density was positively correlated. Populus euphratica requires 22.6kg nutrients to be absorbed from the soil for every 1t of biomass produced. The rate of nutrient accumulation in leaves is significantly higher than that of other organs, and the litter plays an important role in nutrient cycling.