中文摘要：

研究了玛曲高寒沙化草地3种灌木山生柳（Salixoritrepha）、紫穗槐（Amorpha fruticosa）和沙棘（Hippophae rhamnoides）根际与非根际土壤各种磷组分。结果表明，除沙棘外，其余2种灌木根际OlsenP（有效磷包括H2O-P和NaHCO3-Pi）含量高于非根际土壤；3种灌木的根际全磷含量均大于非根际全磷含量。除沙棘以外，其余2种灌木Hz（）一P（水溶性磷）含量根际均高于非根际。3种灌木NaOH—Pi（0．1mol·L^-1 NaOH提取无机磷）和NaOH—Po（0．1mol·L^1NaOH提取有机磷）根际含量均高于非根际含量。DHCl—Pi（1mol·L^-1 HCl提取无机磷）含量除沙棘外其余2种灌木根际均大于非根际。HHCl-Pi（浓HCl提取无机磷）除紫穗槐外根际含量均小于非根际，HHClPo（浓HCl提取有机磷）含量除山生柳外，其余表现为根际大于非根际。对根际、非根际土壤全磷、有效磷含量和pH值进行相关性分析，根际、非根际土壤有效磷和全磷含量相关性不显著，除沙棘外，根际和非根际土壤有效磷和pH值呈负相关关系。

英文摘要：

Three native shrubs inhabiting in Maqu county, including Salix oritrepha, Amorpha fruticosa and Hippophae rhamnoides, were used as materials to investigate the differences of total P content, available P content and P fractions between rhizosphere and non-rhizosphere soils. It was found that there was a higher available P concentration in the rhizosphere soil comparing to that in the non-rhizosphere soils of A. fruticosa and S. oritrepha. The total P content in the rhizosphere soil was higher than that in the non rhizosphere soil of the three shrubs. The concentrations of total P and H20-P were lower in the non rhizo- sphere soil than that in the rhizosphere soil except H. rhamnoides. The contents of NaOH-Pi and NaOH- Po were higher in the rhizosphere soil than that in the non-rhizosphere soil of the three shrubs. The con- centration of HHCl Pi in the rhizosphere soil was lower than that in the non-rhizosphere soil except A. fruticosa. The concentration of HHCl-Po in the rhizosphere soil was higher than that in non-rhizosphere soil except S. oritrepha. Regression analysis indicated that there was a negative significant relationship be- tween available P concentration and pH in both soils of S. oritrepha and A. fruticosa, but no relationship was found between total P and available P concent in both of the rhizosphere and non-rhizosphere soils.