Zuo Xiao-an, Zhao Xue-yong, Zhao Ha-lin, Li Yu-qiang, Guo Yi-rui, Zhao Yu-ping
Naiman Desertification Research Station, Cold and Arid Regions of Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China.
Huan Jing Ke Xue. 2007 May;28(5):945-51.
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.
本研究分析了科尔沁沙地六种典型生境（湿草甸、干草原、固定沙丘、半固定沙丘、半流动沙丘和流动沙丘）中物种多样性和生产力与土壤性质的关系。随着沙地草原退化过程中植被和土壤性质的变化呈现出以下趋势：（1）生产力逐渐降低；（2）物种多样性呈近似正态分布变化，首先从湿草甸、干草原到固定沙丘增加（达到峰值），然后从半固定沙丘、半流动沙丘到流动沙丘降低，而（3）土壤细沙、粉沙、土壤有机碳、全氮和电导率含量持续下降。采用典范对应分析（CCA）排序技术研究植被格局与土壤参数之间的关系。结果表明，土壤有机碳、全氮、有效氮、有效钾、土壤含水量、pH值和电导率是该地区植被格局的主要影响因素。这些因素与前两个典范轴密切相关，占物种 - 土壤性质关系的40%，土壤养分是决定主要植被类型和格局分布的关键因素。此外，群落物种多样性或生态优势度与土壤因子梯度之间的相关性显著，表明物种多样性和生产力的变化受土壤养分、土壤含水量、pH值和电导率的影响。生产力与土壤性质的回归模型表明，土壤养分是群落生产力的关键因素，占生产力 - 土壤性质关系的86.73%。
