[Changes of species diversity and productivity in relation to soil properties in sandy grassland in Horqin Sand Land].
This study provided the analysis of changes of species diversity and productivity in relation to soil properties in six typical habitats (wet meadow, dry grassland, fixed dune, semi-fixed dune, semi- shifted dune, and shifted dune) in Horqin Sand Land. The changes of vegetation and soil properties, following the degraded process of sandy grassland, show the following trends: (1) productivity decreases gradually, (2) species diversity changes in a pattern of near-formal distribution, firstly increases from wet meadow, dry grassland, to fixed dune (at the peak), and then decreases from semi-fixed dune, semi-shifted dune, to shifted dune, while (3) contents of soil fine sand, silt, soil organic carbon, total nitrogen, and electrical conductivity, decrease consistently. Ordination technique of canonical correspondence analysis (CCA) was used to examine the relationship between the vegetation pattern and soil parameters. Results show that soil organic carbon, total nitrogen, available nitrogen, available potassium, soil water content, pH and electrical conductivity are main factors of vegetation pattern in this area. These factors are closely related to the first two canonical axes, accounting for 40% of the species-soil properties relationship, and soil nutrient is the key factor for determining the distributions of the major vegetation type and pattern. Furthermore, the correlation between species diversity or ecological dominance of the communities and gradient of soil factors is significant, shows that changes of species diversity and productivity are affected by soil nutrients, soil water content, pH and electrical conductivity. The regression model of productivity and soil property reveals that soil nutrient is the key factor to community productivity, accounting for 86.73% of the relationship between productivity-soil properties.
Zuo
Xiao-an
XA
Naiman Desertification Research Station, Cold and Arid Regions of Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China. xazuo@126.com
Zhao
Xue-yong
XY
Zhao
Ha-lin
HL
Li
Yu-qiang
YQ
Guo
Yi-rui
YR
Zhao
Yu-ping
YP
D044822:Biodiversity; D018533:Biomass; D002681:China; D006109:Poaceae / Q000145:classification / Q000254:growth & development*; D012822:Silicon Dioxide / Q000032:analysis*; D012987:Soil / Q000032:analysis*; D014197:Trees / Q000145:classification / Q000254:growth & development*
D012987:Soil; D012822:Silicon Dioxide