LAUSR

The functional traits of plant leaves are considered to have significant effects on the survival, growth, and reproduction of plants. These traits are thus widely used to explain complex ecological processes at different levels. In this study, measurements of leaf morphological traits and photosynthesis taken from plants growing along typical slope aspect gradients in a subalpine meadow of Gannan were utilized to characterize the soil factors of each aspect, differences in plant species(Kobresia humilis, Gueldenstaedtia verna, Taraxacum lugubre, and Potentilla fruticosa), and correlations between the photosynthetic and morphological characteristics and soil factors. The following results were obtained (1) Soil factors were distinctly different on different slopes. Soil water content ( SWC), soil total phosphorus (STP), soil total nitrogen (STN), and soil organic carbon (SOC) were generally higher on the northern slope (N) than on the southern slope (S), whereas soil temperature (ST) and light intensity (LI)were apparently greater on S than on N. (2) The specific leaf area (SLA), net photosynthetic rate (Pn), and leaf d C value were significantly different among the different plant species. SLA and leaf water content (LWC) were higher on N, where as Pn, SPAD, leaf dry matter content (LDMC),and d C were higher on S. (3) Redundancy analysis showed a high correlation between leaf traits and soil factors. In particular, SWC showed the most sensitive response to change. This study revealed that the significant differences in plant leaf functional traits at different slope gradients in a subalpine meadow enables species to coexist in the same grassland htt p:/ /w ww .ec olo gic a.c n http: / / www.ecologica.cn community.