Dynamics of Species Diversity and Achievement of Restoration Vegetation in Xinfeng Typical National Demonstration Zone, SE China

摘要

Xinfeng, is the typical region of the vegetation restoration of serious soil and water loss zone in Jiangxi Province, in which dynamics of species diversity and achievement of 6 restoration communities were analyzed using three diversity indices, Detrended correspondence analysis (DCA) and Detrended canonical correspondence analysis (DCCA). Investigations were carried out in 2004yr and 2008yr. The results were as follows: (1) In comparison with 2004yr, flora and dominant families (with much genus and species) of this region increased in 2008yr, especially for Compositae. (2) Total richness and all diversity indices of shrub layer in 6 communities in 2008yr were higher than those in 2004yr. All diversity indices of tree and herb layer in communities IV, V and VI in 2008yr were higher than those in 2004yr. All diversity indices of tree, shrub and herb layer in types of closing hill for afforestation (II, IV and V) and types of mixed tree species (II, V and VI) were higher than those in pure forest without afforestation conservation (I and III), and type of closing hill for afforestation-mixed tree species (V) and type of mixed tree species (VI) showed highest species diversity. (3) The second DCA axis showed gradients of restoration modes and species construction. The first DCCA axis showed gradients of soil status, communities of restoration vegetation; the second DCCA axis showed gradients of surface runoff and community coverage. To summarize, variation in species richness and species diversity is related to without afforestation conservation and mono-tree species, and the need for conservation in the process of vegetation restoration is emphasized. High diverse mixed species in restoration and closing hill for afforestation (avoiding disturbance) in this region can maintain high species richness and diversity.