中文摘要：

高寒地区沙化草地草本植物多样性恢复是沙化治理过程中的重要环节。迄今为止,较为全面分析高寒沙化草地土壤因子与草本群落物种多样性的研究较少。为明确高寒草原沙化草地土壤因子与地上草本群落物种多样性的关系,于2014年7月,在川西北高寒地区通过调查和采样分析来研究不同草本群落物种多样性和不同土层土壤因子之间的关系。结果表明：随着沙化,草地草本群落由湿生型向旱生型转变;沙化草地草本群落物种多样性降低;沙化草地土壤水分和土壤碳、氮、磷含量降低;5～15cm土壤水分、0～15cm土壤铵态氮含量、0～15cm土壤全磷含量和地上草本群落物种多样性显著（P〈0.05）相关。在高寒草地沙化治理过程中,恢复地上草本群落物种多样性应该充分考虑不同土层土壤水分含量、铵态氮含量和全磷含量的影响。

英文摘要：

Increasing species diversity of plant community in the alpine region is an important part in the process of desertification control.As yet,few complete studies have been given to the relationships between soil factors and species diversity of herbaceous community in Alpine sandy grassland.To explore the relationships between soil factors and plant species diversity in the north-west of Sichuan province,we surveyed the plant species diversity in varying degrees of desertified grassland and soil factors in different layers in July,2014.Results showed：along with the process of desertification,herbaceous communities transfered from hygromorphism to xeromorphy and the species diversity decreased significantly;soil moisture,soil carbon,soil nitrogen and soil phosphor also decreased with grassland degradation process.The soil moisture of 5～15cm,ammonium nitrogen and total phosphor content of 0～15cm layer had significant influence on species diversity of community.In the process of controlling the desertification and recovering the plant communities in alpine area,we should consider more about the factors of soil system,especially the content of soil moisture,soil ammonium nitrogen and soil phosphor.