Natural restoration process and diversity change of vegetation on abandoned cropland of Bashan Mountain region
WEI Zhen-Rong-；Xiao-Yun-Li-；Li-Dui
1.Institute of Soil And Water Conservation,Chinese Academy of Sciences and Ministry of Water Resources;2.Northwest Agriculture and Foresty
University:712100,Yangling,Shaanxi;3.Graduate School of the Chinese Academy of Sciences,100049,Beijing:China
Abstract：Bashan Mountains,a transition region of North and South China,is an important area of water resources retention in China.The researches on change characteristics of species diversity index and succession process of vegetation restoration on abandoned cropland are very important for artificial vegetation construction.We studied the changes of species diversity on abandoned cropland during natural restoration process of vegetation by using the methods of substituting space series for time series.Results show: 1) The vegetation succession order on abandoned cropland of Bashan Mountains is annual herb community,perennial herb community,miscellaneous shrub and herb community and broadleaf forest community dominated by Quercus variabilis or Quercus variabilis and Quercus baronii,and it generally takes 40-50 years to form this community.2) Species diversity changes with the site environment.All species diversity indexes on shady slope are obviously higher than sunny slope,but nearly with the same change law.In early succession stage,species number,Shannon-wiener index,Simpson index and Pielou index are lower comparatively.With the increase of succession time,all community diversity indexes increase wavily.In the twenty-fifth year of the succession stage,species number,Shannon-wiener index,Simpson index and Pielou index reach to maximum,which are 23,2.5,0.89 and 0.8.When vegetation develops to zonal plant community,all species diversity indexes decrease a little bit,and tend to stablility.This result is very meaningful for ecological improvement by natural vegetation restoration and manual management of vegetation accoding vegetation succession process.
2010, Vol. 8 
