| With hilly and mountainous degraded land conditions in the middle and lower basin ofYangtze River and the ecological projects construction at the present in China. The ecologicalcharacteristics of community structure, species diversity, its ecological effects on soil health,and eco-system functions of soil water holding capacities, water and soil conservation effectswere studied symmatically in Nverzhai watershed, which was the key experiment anddemonstration spot of the Yangtze River Proctction Forests (YRPF) project and Conversion ofFarmland to Forests (CFF) project.1. By means of community survey methods, in even typical vegetation patterns, whichincluded P. massoniana natural forest (C1), C. lanceolata plantation (C2), E. ulmoidesplantation (C3), V.fordii plantation (C4), M. pingii secondary forest (C5), P. edulis-C. lanceolatamixed forest (C6), wasteland-shrub community (C7), plant species were belong to 89 families,175 generas and 221 species which included 83.15 percentage families and 82.29 percentagegeneras that were composed of one or two species. Aggregated distribution was the main typesof dominant populations' distribution patterns that could to promote the ecological restorationprocess.2. Through bio-diversity analyzing, C5 had abundant species, the highest Shannon-Weinerindex and evenness in the tree layer. In the shrub layer, there were the biggest speciesabundance in C6, the highest Shannon-Weiner index and evenness and the smallest ecologicaldominance in C4. And C7 had the lowest species abundance, Shannon-Weiner index andevenness, and the highest ecological dominance. In the herbaceous layer, C4 and C1 had thehighest and lowest species abundance respectively. Shannon-Weiner index and evenness wasbiggest in C2 and the highest ecological dominance in C5. On the community level, speciesabundance, Shannon-Weiner index (evenness) and ecological dominance were the highest in C4,C5 and C3 respectively, and the lowest species diversity in C7. The regressive relationshipbetween species abundance, Shannon-Weiner index, evenness and community biomass werefounded. There existed a nonlinear relationship between eclogical dominance and communitybiomass.3. Effects of vegetation restoration on soil health had been studied based on severalquantative methods. The improving effects of vegetation restoration on the soil structure werebetter in forest types than in wasteland-shrub type. Gray incidence analysis result of soilstructure health evaluation demonstrated that C7 had the worst soil structure, and the best in C4. According to soil nutrients, C5 had the highest contents of organic matter, total N, total P,available P and available K, and the lowest contents of organic matter and available N in C7,the lower micro-element in C6. There were the largest bacterial number (72.83％～92.77％) insoil microorganisms, followed by actinomycial number (6.44％～25.61％) and fungous number(0.79％～1.99％). The highest value of microbial biomass C and N occurred in C5, and lowestvalue in C7. C7 had the lowest enzyme activity than six forestry pattern.4. Soil saturated water storage in forest communities were higher about 25.34％～75.04％than in C7 which proved that forests had relatively obvious functions of meliorating soilproperties and enhancing soil water holding capacity. The common experienced infiltrationmodel was the most suitable for simulating the infiltrating processes in different vegetationcommunities. Based on principal component analysis, the closely relative factors of soil waterinfiltration properties were picked out, which included soil water holding capacity, porosity,forestry structure, vegetation biomass, elevation, slope degree and slope position, and slopedirection, herbaceous layer coverage ratio and soil bulk density had little bearings on theinfiltration. Through double sieving stepwise regression analysis, the driven factor equations ofinitial infiltration rate, stable infiltration rate and mean infiltration rate had been formatted.5. The runoff and sediment in C4 were highest in a 100m2 plot, which were 6.6977m3 and0.5283kg, and the lowest in C5, C7, the value only 0.8095～1.7454m3, 0.0834～0.1229kg.There existed a extraordinary linear relationship between runoffs and sediments. And theinfluence of rainoffs on runoffs and sediments could be described well by linear, quadratic andcubic equations. Through double sieving stepwise regression analysis, Contrary to elevationand slope degree, soil structure factors, soil water holding storage and vegetation coverageratio had much beating on runoffs and sediments. The key factors of runoffs were Waterstorage in capillary porosity and total porosity, and the key factors of sediments were minimumwater holding storage and water storage in capillary porosity.6. Soil health evaluation system had been found which contained 60 indexes that belongedto vegetation subsystem, soil subsystem and topographical factors. The comprehensive effectsof vegetation patterns was C5＞C2＞C6＞C1＞C4＞C3＞C7 by gray incidence analysis.Through the gray incidence arrangement of evaluation indexes, Shannon-Weiner index,capillary porosity, organic matter, sucrase activity had the closest relationship with soil healthrespectively in vegetation characteristics, soil physical, chemical and biological properties.There existed the regularity of slope position＞elevation＞slope degree＞slope direction onwhich topographical factors affected vegetation restoration effects. 7. By ecological restoring, the control of water and soil loss and the prevention of landdegradation had been improved well. The value of ecological restoration suitability index was0.9239. Forestry was the watershed matrix for that forestry had the biggest area (284.50hm2)and the most patch number porpotition (73.49%). Patches had relatively simple shape, a biggersimilarity among them, and a lower effective landscape area. Contrary to the lower evennessand bigger deviation, the diversity (2.4164) was higher relatively. Fragmentation of watershedwhole landscape was not very high (0.5415), however, the landscape type of residential areahad the most highest fragmentation (2.1739) which was harmful for landscape eco-systemsteadiness. The countermeasure of vegetation restoration in the watershed should be closinghillsides to facilitate afforestation, and adopting manual measures at the time.
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