Community Assembly On The Habitat Gradient Of Slope Aspects In Sub-alpine Meadow Based On Functional Traits

In ecology, the research of community ecology is one of the important part, and to clarify the mechanism of community assembly is awalys a hot spot in community ecology. Community assembly, which means the mechanism of the coexistence of species and maintain of biodiversity. Niche theory and neutral theory are two basic theories which aim at studying this mechanism. The study of community assembly helps us clear the nature of communities’ development, and forecast the directions of community succession in the future, also, it has significance to protect and use properly the ecological environment around us. Our text bases on niche theory, focuses on the plants’ functional traits in sub alpine meadow. We analyze the important roles of habitat filtering and limiting similarity in community assembly, explore community assembly in the gradient of different slope aspects of hills. The results are:1)In the environment of sub alpine meadow, height of plants, specific leaf area, leaf total phosphorus content and the ratio of nitrogen and phosphorus, gathering in sunny slope, while diverge in shady slope. The correlation between the average trait(height, specific leaf area, leaf total phosphorus content) and some environmental factors, from sunny slope to shady slope showed a downward trend. Therefore, In the sunny slope, due to convergence of functional traits and the tight correlation between functional traits and the environmental factors, habitat filtering process is dominant in community assembly, while in the shady slope, due to the divergence of functional traits and weak correlation between traits and the environmental factors, limiting similarity is dominant in community assembly; 2)N:P of soil decreases significantly, while soil water content increases significantly from sunny slope to shady slope; 3)The average height and SLA of plants in shady slope are significantly higher than sunny slope, while TN content of plants in shady slope are significantly lower than sunny slope; 4) As two trade-off traits related to light competition, the plant height and specific leaf area are significant positive correlation; 5)Species abundance increases significantly from sunny slope to shady slope, and there is no significant correlation between richness and functional diversity of plants.We use the functional traits of plants as tools, and make a conclusion that community assembly mode of different slope aspects is different in subalpine meadow. Further, indicate that slope aspects have great impact on plants diversity and functional traits, even the formation and development of community.