Abstract: The soil properties of natural alpine grassland (NG),degraded "black-soil mountain" alpine grassland (BG) and artificial alpine grassland (AG) were measured to investigate the soil carbon,nitrogen,phosphorus contents and other ecological stoichiometry characteristics of degraded and artificial grasslands in the Three Rivers Source Region. The results showed that the soil total nitrogen (TN) and potassium (TK) contents of the BG and NG communities were significantly higher in the sunny slope than on those counterparts in the shady slope;the total phosphorus (TP) content of the AG community was significantly higher in the shady slope than that in the sunny slope;the ratios of carbon to nitrogen,nitrogen to phosphorus and carbon to phosphorus of the soils in both shady slope and sunny slopes were in a trend of NG>BG>AG. A three-way ANOVA showed that slope orientation significantly influenced all soil indicators except for available nitrogen (AN) and soil organic carbon (SOC),and grassland community significantly influenced all soil indicators except for available potassium (AK) content and pH value. Furthermore,the soil layer significantly influenced soil fast-acting nutrients and soil organic carbon.

Key words: Black-soil Mountain degraded grassland, Soil layer, Slope aspect, Grassland community, Ecological stoichiometry

摘要： 本研究以三江源区阴阳坡天然(NG)、退化“黑土山”(BG)、人工(AG)高寒草地为研究对象，通过土壤性质的测定，探讨三江源区退化草地与人工草地土壤碳氮磷及生态化学计量特征。结果表明，阳坡BG样地全氮(Total Nitrogen，TN)含量、NG样地全钾(Total potassium，TK)含量显著高于阴坡；AG样地全磷(Total phosphorus，TP)含量阴坡显著高于阳坡；阴坡和阳坡土壤碳氮比(C∶N)、氮磷比(N∶P)和碳磷比(C∶P)均呈现NG>BG>AG的趋势。全氮含量整体呈NG

关键词: “黑土山”退化草地, 土层, 坡向, 草地群落, 生态化学计量比