秦岭南坡松栎混交林乔木层生物量沿海拔梯度的变化

采用样地调查与异速生长方程相结合的方法，分析了研究区内森林结构和生物量沿海拔梯度的变化规律及其原因。结果表明:乔木层地上生物量随海拔梯度的上升逐渐下降，松科树种生物量比重随海拔梯度的上升有增加的趋势，但差异不明显。各海拔梯度均受到不同程度的人为或自然干扰，生物量与干扰因子呈显著负相关（r=－0.698, P0.01），其中海拔1 100 m以下受到的人为干扰最严重。与相邻地区相比，研究区地上生物量偏低，建议经营者制定适当的经营措施，以实现松栎混交林的科学经营。 

Changes of arbor layer aboveground biomass of Pinus spp. and Quercus spp. mixed forests along altitudinal gradient on the southern slope of Qinling Mountains, northwestern China.

In this research,the data from field survey and allometric models summarized by other experts were combined to analyze the changing rules of forest structure and biomass along altitudinal gradient. The results revealed that aboveground biomass showed a decreasing trend with the increase of altitude gradient. Simultaneously,the biomass proportion of Pinaceae increased with no significant difference. Forests at each altitude were destroyed in different degrees by natural or anthropogenic disturbance, especially under the elevation of 1 100 m. In general,biomass was negatively related to interference factors ( r = - 0. 698,P < 0. 01) . Compared with other neighboring regions,the biomass of Pinus spp. and Quercus spp. forest was relatively lower in this region. So this research suggests that reasonable management strategy should be made to meet the optimal development.