卧龙自然保护区油竹子形态学特征及地上部生物量对海拔梯度的响应

Responses of the Morphological Peculiarities and Above-ground Biomass of Fargesia angustissima to the altitudinal Gradients in Wolong Nature Reserve

海拔梯度由于包含了温度、湿度等诸多环境因子的剧烈变化而成为了研究植物的环境适应性及其对全球气候变化响应的理想区域。在卧龙自然保护区沿海拔梯度研究了油竹子(Fargesia angustissima(Mitford)T.P.Yi)分株的比叶面积(Specific Leaf Area,SLA)、基径(Basal Diameter,D)、株高(Height,H)、分株节数及节间长、单株地上部分各器官生物量及生物量分配。除分株节数随海拔升高近似线性增加,和分株枝生物量随海拔升高线性降低外,其他各调查因子对海拔的响应均是非线性的,反映了环境因子随海拔的非线性变化。分析认为,油竹子的生长受降水的影响较大,可能会对因为全球气候变化导致的降水模式变化更为敏感。

The altitudinal gradients leading to radical variations in environmental conditions in mountain regions provide unique and sometimes the best opportunities to study plant responses and adaptation to global climate changes.In this paper,investigatedions were conducted on the morphological characteristics（Specific Leaf Area,basal diameter,height,and internode number）,aboveground biomass and its allocation of Fargesia angustissima（Mitford） in 4 plots along the altitudinal gradients ranging from 1 200 m（the lowest distribution boundary of F.angustissima） to 1 810 m（the uppermost distribution limit） in the Wolong Nature Reserve,southwestern China.Except for a nearly linear increase in internode number and a linear decrease in shoot biomass with the increasing of the elevation,other parameters displayed non-linear changes with the increasing of the elevation.These results may imply that the local-environmental conditions do not exhibit linearly changes with the altitude.The growth of F.angustissima,as a low-altitude species,may be impacted by precipitation rather than by temperature.Hence,this dwarf bamboo species may be more sensitive to changes in the amount and patterns of precipitation caused by global climate changes.