中文摘要：

在缺苞箭竹-紫果云杉原始林下选取5个密度的缺苞箭竹，研究密度对缺苞箭竹生物量、C及养分贮量分配的影响。结果表明：在一个生长季中，缺苞箭竹生物量、净生产量、平均单株生物量、植物及土壤的C、养分贮量在（80±5～260±9）株·m^-2密度范围内随密度的增大而增大，在高密度（310±15）株·m^-2时有所降低，210～260株·m^-2。是缺苞箭竹最适密度范围。各密度缺苞箭竹养分元素贮量排序总体上均为K〉N〉Ca〉P〉Mg。在密度较低时，地下部分C及养分贮量分配比例相对较高，有利于其占据土壤空间资源，而随密度的增高，地上部分比例增高，有利于其占据地上空间资源，反映了缺苞箭竹随密度变化的克隆生长生态适应对策。在缺苞箭竹-土壤系统中，植物与土壤C库贮量比率随密度的增大逐渐升高，在高密度时有所降低。土壤5种主要全量养分库贮量较丰富。土壤速效N、K养分库在各密度之间差异不显著，而速效P库则随密度的增大而逐渐降低。表明土壤速效P库的不足是缺苞箭竹生长的主要限制因子。

英文摘要：

The effects of the density on the storage of biomass,carbon and nutrient elements were investigated under five kinds of Fargesia denudata communities with different density in the primitive F. denudata-Picea purpurea forest in May and October, 2005. At the end of growing season, the total biomass, net production, average stem biomass, carbon and nutrient storage of plant and soil all increased from （80 ± 5） trees·m^-2 to （260±9） trees·m^-2 but decreased at （310 ± 15） trees·m^-2 ,showing that the suitable stem density range was from 210 to 260 trees· m^-2 for the bamboo to grow. The order of nutrient storages was K 〉 N 〉 Ca 〉 P 〉 Mg for all bamboo communities. As a whole, for the lower density communities, carbon and nutrient were allocated more to below-ground for occupying below-ground spatial and nutrient resource, but more to above-ground for those with higher density to occupy above-ground spatial resource, implying that the ecological adaptive strategy of F. denudata was primarily determined by the density. Furthermore, in the system of plant and soil, the carbon storage ratio of plant to soil increased with density increasing but decreased at the highest density. Though the nutrient storages of N, P, K and Mg were abundant in soil, and the storage of available N and K had no more difference, among all densities, the storage of available P decreased with density increasing, implying that the lack of available P regulated the growth of F. denudata community.