The Research Of Water Ecology For Some Main Vegetation With Soil And Water Conservation Effect In Loess Hilly And Gully Region

Soil and water erosion and the ecosystem degeneration are the most serious ecological environment question in the Loess Plateau, China, the massive unreasonable land utilization causes the vegetation destruction is the primary cause which the aggravating loess plateau soil erosion and the environment worsen. Therefore, the vegetation construction is the important method which this area conservation of soil and water and the ecological environment worsen, studies the ecological adaptability of different vegetation types and suitable species collocation were the scientific basis for vegetation restoration in semi-arid zone.This study through to the Small watershed typical vegetation type under the soil hydrology physical property, the soil moisture and the photosynthesis physiology characteristic on the spot observation, and discussed different vegetation type earth soil hydrology physical property change, the soil moisture validity and Water deficit and their ecological adaptability under different vegetation type; Meanwhile has conducted the research to the indigenous main tree species being suitable soil moisture and PAR, proposed the different tree species reasonable site layout option. The main result are as follows:(1) Vegetation construction has the improvement function to the soil hydrology physical property. On the shady slope, the change for soil hydrology physical properties under different Vegetation types, it showed Robinia pseudoacacis forest land>Caragana microphylia Lam. Forest land>the mixed forest land of Robinia pseudoacacis and Pinus tabulaeformis>natural shrub grassland> Hippophae rhamnoides L.forest land. On the suuny slope, it showed Rose Malus forest land> Robinia pseudoacacis forest land>shrub and grass terrace>Juglans regia L. forest land>natural shrub grassland>Prunus armeniaca linn.var.anus Maxim. forest land.(2) The soil permeability curve may divide into three stages approximately: Penetration coefficient transient stage, gradation stage and steady stage. On the shady side of a slope various vegetations type the 0~40cm soil layer, the stable infiltratio rate under differents vegetation restoration types was: natural shrub grassland > Robinia pseudoacacis forest land > Caragana microphylia Lam. forest land> the mixed forest land of Robinia pseudoacacis and Pinus tabulaeformis> Hippophae rhamnoides L. forest land; On the sunny slope various vegetations type the 0~40cm soil layer, the stable infiltratio rate under differents vegetation...