| Yanchi County of Ningxia Hui Autonomous Region is a typical Ecotone of Agriculture-animal Husbandry in northern part of china. For the past few years, the extensive vegetation restoration played an important role in preventing land degradation and improving the ecological environment. The process of vegetation restoration had a greater impact on landscape and ecosystems in Yanchi County. To study the regularity of its changes has important ecological significance. This paper, basing on remote sensing image and ground survey, used the modern "3S" technology and landscape ecology principles, analyzed 10 years of land use/cover changes and landscape dynamics of Yanchi County from the macroscale; and basing on Restoration Ecology, Plant Ecology, Soil Science, Hydrology and other related theories, used the method of field tests and laboratory experiment, researched the ecological effects of different vegetation restoration from the regional scale of vegetation types of ecosystems, community structure, soil quality, water hydrological effects, wind erosion control effects; and established the ecological effect evaluation index system, evaluated the ecological effect of the different vegetation restoration process. The major research results were as follows:(1) The land use/cover was changed greatly during the process of vegetation restoration in Yanchi County. From 1999 to 2009, in different periods, the agricultural land been showing decreased by the county total area of 21.78% to 18.49% reduction, reducing 22180.19 hm2;forestland had been showing increasing trend from the county total area of 9.79% to 13.08%, increasing 22179.6 hm2, the source of its growth was mainly grassland, followed by agricultural land; residential and industrial land had been showing increasing trend from the county total area of 1.28% to 4.20%, increasing 19708.12 hm2; unused land had been reducing significantly since 1999, mainly the floating sandy land reduction, which reduced some of the major converted to forestland and grassland.(2) The landscape dynamics was changed greatly during the process of vegetation restoration in Yanchi County. Type level, in different periods, the sequencing by the mean patch space (MPS) of the first level land use classification, was grassland> farmland> forestland> unused> waters> residential and industrial land, and the second level land use classification, the MPS of the high and low cover degree cover grassland changed obviously with the time, but the other types did not; the patch size coefficient of variation (PSCV) changes showed a decreasing trend in generally, degree of dispersion decreased; various types of grassland in the largest patch index (LPI) were significantly higher than other types, reflecting the matrix interaction of grassland; the LPI of Wood land was rising, while the LPI of dry land and sparse woodlot were reducing, which showed that ecological construction attained good results. Landscape level, the landscape fragmentation and heterogeneity increased from 1999 to 2003, while decreased from 2003 to 2009 in Yanchi County; largest patch index (LPI) and the patch size coefficient of variation (PSCV) showed a smaller range of fluctuation; the area weighted mean shape index (AWMSI) and area weighted mean fractal dimension (AWMPFD) had small differences among different periods, explaining the rules of patch shape and complexity of patch edge changed little. Landscape Diversity (SHDI) and evenness (SHEI) showed minor fluctuations, but overall steady growth, which showed that nearly 10 years in different types of landscape area were between the relatively uniform distribution, landscape heterogeneity increased. The contagion index (CONTAG) decreasing and Interspersion and Juxtaposition Index (IJI) increasing year by year changed in contrast, showed that various types of landscape patches appeared in the spatial distribution of equalization.(3) The ecological effects of the process of vegetation restoration were significant in Yanchi County. By the restoration process, number of species increased, species richness gradually increased, the community dominance index, diversity index had increased more than the agricultural land, community ecology effect was obvious. The plant communities with interspersed roots improved the soil physical properties, soil bulk density decreased, porosity increased, the permeability of the soil increased with infiltration performance enhancement; soil particle composition also occurred in some of the changes in soil aggregate content, water stable aggregates gradually increased the corrosion resistance of the soil gradually. Different vegetation restoration on soil nutrients had significantly improved, soil organic matter, total N, total K and available N, P and K contented significantly. Depth and density of root distribution among different vegetation types made the different soil evaporation and plant transpiration, therefore the soil water content existed significant differences. The role of interception to rainfall by Canopy of vegetation decreased and weakened splash on soil erosion, and different vegetation restoration displayed differently. Litter was an important part of interception to rainfall, because of the selected site type of herb to shrub, water capacity with the litter layer was relatively small. The different vegetation restoration process had influence on changing surface and wind speed, and played an important role in wind erosion controlling. Vegetation species, vegetation community characteristics, soil physical and chemical properties, soil moisture, hydrological and other ecological factors were interrelated and interactive, and between different ecological factors related to different degrees.(4) In Yanchi County, the ecological effects index of vegetation recovery was in (0.4-0.6), with evaluation of an intermediate. Different types of ecological effects index (EEI) with the size of the order: natural grassland> grain for green land> manually fencing grassland> abandoned land> fixed sand land> agricultural land. The vegetation restoration had a positive effect in the community, soil physical effects, soil chemistry effects, water effects wind erosion control and so on, promoted the ecological environment improvement and reversal of desertification in Yanchi County. Therefore, in Yanchi County combining with physical geography and socio-economic conditions to promote ecological construction is important protection for sustainable development of ecological environment.
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