呼伦贝尔沙地北部沙带植物群落分布格局与土壤特性的关系

研究呼伦贝尔沙地植物群落与土壤特征相互关系有助于促进中国北方的生态恢复与重建工作。分析了呼伦贝尔沙地北部沙带58个样地174个样方的植物和土壤的调查数据，调查到94种植物，分属于26科64属，其中菊科（Compositae）、禾本科（Gramineae）、豆科（Leguminosae）和蔷薇科（Rosaceae）为前四大科，占总物种数55.33%。采用Ward系统分类法，将所调查植被分为4类。寸草薹-二裂委陵菜群落（Carex duriuscula-Potentilla bifurca） Tsallis多样性最高，冰草-星毛委陵菜-糙隐子草群落（Agropyron cristatum-Potentilla acaulis-Cleistogenes squarrosa） Tsallis多样性最低。不同植物群落间土壤物理特性有显著差异，化学特征差异不显著。随着土层深度的增加，各群落土壤全氮、全磷、有机质含量逐渐降低，表聚现象明显，脚薹草-贝加尔针茅群落（Carex pediformis-Stipa baicalensis）和冰草-星毛委陵菜-糙隐子草群落养分层次特征显著，羊草群落（Leymus chinensis）和寸草薹-二裂委陵菜群落养分层次特征不明显。CCA排序结果表明影响植被群落物种分布的土壤因子有全氮、全磷、有机质、pH和土壤水分，其中深层土壤全氮、全磷、有机质（20~40 cm土层）的作用最显著。呼伦贝尔沙地北部沙带植物群落分布存在较显著差异，呈现出斑块状分布规律，而土壤养分对植被群落格局具有重要影响。

Relationship between plant community distribution pattern and soil characteristics in northern sand belt of Hulunbuir Sandland

The study on the relationship between plant communities and soil characteristics in Hulunbuir sandyland is helpful to promote the ecological restoration and reconstruction in northern China. Based on the analysis of the survey data of 174 plots in 58 sample sites in the northern sand belt of Hulunbuir sandyland, it is found that 94 species of plants belong to 26 families and 64 genera. Among them,Compositae, Gramineae, Leguminosae and Rosaceae are the first four families, accounting for 55.33% of the total species.The investigated vegetation was divided into four types by Ward system classification. The Tsallis diversity of Carex duriuscula-Potentilla bifurca community was the highest, and the Agropyron cristatum-Potentilla acaulis-Cleistogenes squarrosa community was the lowest. There were significant difference in soil physical properties among different plant communities, but no significant difference in chemical characteristics. With the increase of soil depth, total nitrogen, total phosphorus and organic matter in each community decreased gradually, and the phenomenon of surface aggregation was obvious.The nutrient level characteristics of Carex pediformis-Stipa baicalensis, and Agropyron cristatum-Potentilla acaulis-Cleistogenes squarrosa community were significant, but the characteristics of Leymus chinensis, and Carex duriuscula-Potentilla bifurca community was not obvious. The results of CCA ordination showed that the soil factors affecting the species distribution of vegetation community were total nitrogen, total phosphorus, organic matter, pH and soil moisture, among which the effect of deep soil total nitrogen, total phosphorus and organic matter (20-40 cm)were the most significant. There are significant differences in the distribution of plant communities in the northern sand belt of Hulunbuir sandyland, showing a patch distribution, and soil nutrients have an important impact on the vegetation community pattern.