Variations in Functional Traits of Anthoxanthum glabrum(Tvin.)Veldkamp in Different Habitats of Dawutan High-altitude Wetland in the Sanjiangyuan Avea and Its Response to Soil Factors
The Sanjiangyuan area is located in the Qinghai-Tibet Plateau.The study area has diverse ecosystems,including alpine meadows,lakes and wetlands,and it is a hot area for studying species diversity.The expression of plant functional traits is influenced by both genetic characteristics and external environmental conditions,and its functional traits can reflect the adaptation strategy of species to the environment.By means of large sample sampling survey and statistical analysis,the ramets and leaf functional characters of Anthoxanthum glabrum(Trin.)Veldkamp in five habitats of Dawutan alpine wetland(wet habitat A1,semi-wet habitat A2,mesophyte habitat A3,shady dry habitat A4 and sunny dry habitat A5)were comparatively studied,and the differentiation law of functional characters of Anthoxanthum glabrum(Trin.)Veldkamp in different habitats and its response to soil factors were analyzed.The results showed that the coefficient of variation of ramet traits and leaf traits in different habitats were between 2%-13%and 1%-21%,respectively.Among them,the coefficient of variation of ramet traits and leaf traits of Anthoxanthum glabrum(Trin.)Veldkamp is larger in dry habitat on sunny slope,but smaller in wet habitat.The correlation between functional characters of Anthoxanthum glabrum(Trin.)Veldkamp with different habitats.The leaf width in wet habitat was significantly correlated with the length of reproductive branches(0.970),the leaf number in semi-wet habitat was negatively correlated with the leaf thickness(-0.973)and the leaf length was negatively correlated with the crown width(-0.959),and the leaf length in dry habitat on shady slopes was significantly correlated with the fresh quality of reproductive branches.In situ soil factors in different habitats showed heterogeneous characteristics,and the variation of functional characteristics of Anthoxanthum glabrum(Trin.)Veldkamp was the result of the comprehensive action of soil factors such as water content,pH value,organic matter,conductivity,total nitrogen,total phosphorus,alkali-hydrolyzable nitrogen and available phosphorus,among which conductivity was a negative driving factor,and the other soil factors were positive driving factors.Therefore,it is better to adapt to different living environments through self-regulation of functional traits.On the local scale,soil factors in different habitats are the main factors leading to the differentiation of functional traits.