| Evergreen-deciduous mixed broad-leaved forest is the dominant vegetation typein northern or higher region of subtropical mountains, it plays an irreplaceable role in ecological functions. Mulinzi Nature Reserve have the typical native and the secondary evergreen-deciduous mixed broad-leaved forest. This paper discusses the community restorative characteristics of environment, composition, structure and the response mechanism between environment and vegetation by using the basic methodology of restoration ecology, in order to provide scientific basis for forestry and ecological construction. The results are as follows:(1) Different restoration stage communities had the same taxonomic composition characteristics that monotypic families and genera were in the majority. Rosaceae contained the largest number of genera and species. 20-year-old secondary forest(SF20) contained 39 families, 82 genera and 149 species, 35-year-old secondary forest(SF35) contained 48 families, 100 genera and 176 species, old-growth forest(OG) contained 51 families, 94 genera and 151 species. Species composition between different restoration stage communities showed significant variation. During the process of restoration, species composition of secondary forest had a trend toward OG and became more predictable. Except for Pielou’s evenness did not show significant variation during the process of restoration, the other indexes of diversity showed significant variation that increases at first and then decreases.(2) The top 3 dominant species of SF20 were Carpinus fargesiana, Weigela japonica and Cyclobalanopsis glauca; The top 3 of SF35 were Carpinus fargesiana,Symplocos sumuntia and Cyclobalanopsis glauca; The top 3 of OG were Cyclobalanopsis glauca, Eurya alata and Camellia cuspidata. Schima superba,Castanea henryi, Camellia cuspidata, Eurya alata and Cyclobalanopsis glauca populations develop and strengthen their dominance, while Dendrobenthamia japonica, Betula luminifera, Weigela japonica and Carpinus fargesiana populations transferred from prosperity to descent.(3) Different restoration stage communities had the same inverse “J” distribution of diameter structure which has a trend toward to more ecological heterogeneity and stability during the process of restoration. The vertical structure showed similar trend to diameter structure during that process, and difference between communities for thecanopy of OG and SF35 could be divided into 3 layers, while that of SF20 could be divided into 2 layers.(4) During the process of restoration, soil moisture content showed a significant increase especially in the period after 35 years of restoration, soil organic matter and total N showed significant variation that decreased first and then increased, bulk density, total porosity, p H, available K, available N, total P and available P did not show significant variation, canopy openness showed a significant decrease especially in the period between 20-35 years of restoration.(5) During the process of restoration, the significant correlation between soil factors and its universality showed a constantly increase, the major soil formation mechanism changed. Except for the significant correlation between soil nutrient factors and between physical properties, both SF20 and SF35 showed that the supply relationship of SOM to nutrient element, SF35 also showed the correlation between SOM and soil physical properties, OG showed the correlation between p H and nutrient. Both principle component analysis and ANOSIM test showed that the overall variations of environment(soil and canopy openness) between communities were not significant. OG had a stronger environmental heterogeneity than SF20 and SF35.(6) Different restoration stage communities and the overall study area species composition varied significantly and showed different response to environmental factors. The species abundance, richness and basal area pattern of study area showed significant spatial autocorrelation in a few lag distances. Simultaneous autoregression could bring spatial autocorrelation into account to reveal the real vegetation-environment relation of study area: Species richness correlated to soil moisture,abundance and basal area correlated to soil nutrient. Redundancy analysis showed that the correlation(between community species composition and soil nutrient) improved during the process of restoration. Variation partition showed that the importance of environmental selection to community assembly increased during the process of restoration, more variations of community species composition could be explained by environmental factors. |
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