| The research object was YueWu highway slope in the Wanxi Dabie mountain areas. We used the method of the positioning research and community investigation to do research on the artificial vegetation planting the community characteristics and soil properties of highway slope. The research analyzed the community characteristics of different cultivation years (2a,5a,7a and 9a) highway slopes which located in this region. Combined with field investigation, the study built the vegetation recovery evaluation system through three aspects including slope mechanics quality, base material quality and community quality. We also combined the AHP with fuzzy comprehensive method to evaluate the vegetation recovery quality of Yue Wu highway slope. The main results are as following:(1) The community characteristics of slopes were quite different in the early planting vegetation, which took different vegetation recovery measures. After the first year, the species quantity, vegetation cover and community height had clearly dominant in the hydro seeding plot, but they began to deteriorate in the second year. At the same time, the species quantity, vegetation coverage and community height improved obviously in the fiber blanket and lawn nursery strip plots, indicating that they had better stability and sustainability of the community. The improvement of diversity indexes, which suggested that the community structure was evolving from the simple to complex level.(2) The soil characteristics of slope were quite different which took different vegetation restoration measures. After the two-year, in the fiber blanket and lawn nursery strip plots, the soil density declined, and the soil porosity and soil water infiltration capacity increased obviously. The increase content of total N, available P, rapidly available K, OM were largest in the fiber blanket, shear strength of base material increased largest in the fiber blanket and lawn nursery strip plots. This means that the growth and community structure of slope vegetation directly affects the physical properties of soil, soil nutrient content and slope stability, which indicating that the correlation between community characteristics, soil nutrient factors and shear strength of base material was obvious.(3) The highway slope artificial vegetation community characteristics of different restoration years were obvious. In the slopes vegetation recovery early period, the dominant species focused on artificial seeding species, the diversity of community was low. With the restoration of advancing age, the kinds of species were enriched by native species, thereby increasing the species diversity index. With the succession, the dominant species concentrated on a single population, resulting in relatively lower diversity index.(4) With slope vegetation-soil system improving, a lot of Gramineae, Leguminosae, and Asteraceae native plant changed the structure of artificial vegetation community and occupied larger community space. In a further succession, the woody plants began to occupy a larger space community. In the Wanxi Dabie mountain slope areas, the artificial vegetation planting naturalized succession processes were:planting artificial grass and shrub community stage (1～2a), artificial plants and natural plants coexistence stage (2～7a) and tree, shrub and grass community stage (7～9a).(5) The soil seed banks of the highway slope in Wanxi Dabie mountain areas had rich plant seeds. It was a certain degree similarity in species composition between soil seed bank and aboveground vegetation with the different recovery years of slopes.(6) Through the vegetation recovery quality evaluation of YueWu highway slope, the results showed that the vegetation recovery quality level were differences by using the different ecological slope protection mode. The vegetation recovery quality was best in the blanket and lawn nursery strip mode of ecological slope protection. It was most suitable for highway slope vegetation restoration in the Wanxi Dabie mountain areas. |
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