摩天岭北坡植物功能性状对环境因子的动态响应

Plant functional traits,defined as morpho-physio-phenological traits which impact fitness indirectly via their effects on growth, reproduction and survival,the three components of individual performance, link environmental factors,individual plants and ecosystem structures,processes and functions.With the application of the plant functional traits'concept and the improvement of plant traits measurement system,Plant functional traits studies play an important role to reveal the regulations of plant physiology and ecosystem processes,and to analyse the trade-offs of the functional traits from species to community,the classification of the plant functional types based on the plant functional diversity,and to analyse the vegetation dynamic which response to the environmental factors..The project focuses on the present vegetation types and their functional traits at the north slope of Motianling mountain in Baishuijiang National Nature Reserve. According to the field investigation,plant traits(vegetative traits,whole-plant traits,leaf traits,stem traits,regenerative traits etc.) and environmental factors(based ecological factors and geographical space factors),the database of vegetation plot,plant functional traits and environmental factors will be analysed..Statistical methods, such as correlational analysis,ANOVA,regression analysis,classification and ordination analysis will be applied to process data obtained,two key questions of study objectives will be resolved:.1)The dynamic relationship between plant functional traits of species-level and community-level in different environment gradient, and 2)the main determinant of the environmental factors which affect plant functional traits variability in the research area.The trade-offs or differentiation of different traits from species to community levels at different environment gradient. However, due to the differences in phylogenic background, different species may take different strategies in the face of the same climatic gradient,the similarities and differentiations of plant functional traits dynamic based on plant functional types level or phylogenetic level in different environmental gradient will be dissected..The current research will deeply reveals the combine features, spatial patten and adaptive strategy to environmental change of plants functional traits in the northeast edge of Qinghai-Tibet plateau's typical mountain vegetation.and provide a basis for future studies on climate-vegetation interactions and for developing regional dynamic vegetation models for China.

植物性状动态与环境因子关系是近年来全球变化研究中一项十分重要的内容。而从植物功能性状到植物功能多样性以及植物功能型概念的应用和发展，全球范围植物功能性状测度列表和测度方法的逐渐积累和日臻完善，使得进一步定量分析植物性状对区域环境因子的动态响应成为可能，进而更深入地进行植物功能性状与生态系统功能关系的研究。本研究拟通过岷山山系摩天岭北坡自然植物群落样方调查、植物功能性状测度以及环境因子（基础生态因子和地理空间因子）的分析和测定，探讨不同环境梯度下物种水平植物功能性状间的平衡关系，群落和功能群水平基于植物功能性状的植物功能多样性变化，剖析区域尺度影响山地植被植物功能性状的主要环境驱动因子以及功能群水平和系统发育背景植物功能性状的趋同或分异及其对环境因子的响应。研究成果将有助于深刻揭示青藏高原东北缘生态过渡带植物功能性状组合特征、空间格局及其对环境变化的响应和适应规律。

摩天岭北坡森林生态系统植物群落组成复杂，项目组成员在摩天岭北坡区域野外采集植物标本1800余号。经初步统计该地区有高等植物197科，2160种；19亚种；239变种；12变型。由水热条件及其组合特征影响的植被垂直分异明显，表现为植物功能性状对植被群落动态的强烈响应与指示，这种植被格局对森林植被演替恢复过程有重要的影响。研究了植物功能性状对环境因子的动态响应，结果表明：摩天岭北坡海拔500-3500m地段，有着完整的山地植被垂直带。（1）不同海拔梯度下的植物群落各类多样性指数均呈现出连续的“~”型变化趋势，灌木层和草本层的变化趋势趋同；（2）研究区植物比叶面积(SLA)、叶干物质含量（LDMC）、叶氮含量(LNC)、叶磷含量(LPC)以及叶碳含量(LCC)等相关植物叶性状变化趋势复杂，通过系统聚类法可将所有调查的木本植物分为8大功能群。（3）植物群落水平叶片化学计量学指标呈现不同的变化趋势：C含量随着海拔梯度增加而显著升高( P =0.17)， N含量随海拔的升高而显著增加( P =0.26)， P含量变化趋势不显著( P =0.69)。（4）木本植物的叶片N/P呈正态分布。各植物间叶片的N/P差异很大；（5）土壤的全C、全N随海拔梯度逐渐降低；土壤全 P随海拔得升高而显著降低；土壤速效养分指标随海拔的升高呈现逐渐增加的（P=0.43)变化趋势；（6）植物群落调查发现甘肃新记录属2个，新记录种3个。