中文摘要：

以青藏高原东缘4种不同类型草地（高寒草甸、高寒灌丛、沼泽化草甸、山地草原）为研究对象,分析了不同类型草地土壤理化性质、土壤酶活性的变化特征及其相互关系。结果表明,4种类型草地土壤表层（0～15cm）的酶活性均高于其下层土壤（15～30cm）,而且随草地类型变化的趋势基本一致;土壤β-葡萄糖苷酶活性在4种类型草地中的变化趋势为沼泽化草甸〉高寒灌丛〉高寒草甸〉山地草原,酸性磷酸酶活性为沼泽化草甸〉高寒草甸〉高寒灌丛〉山地草原,脲酶活性在表层为沼泽化草甸〉高寒灌丛〉山地草原〉高寒草甸,下层为山地草原〉沼泽化草甸〉高寒灌丛〉高寒草甸。相关性分析结果表明,土壤β-葡萄糖苷酶活性、酸性磷酸酶活性与土壤有机碳、全氮含量呈极显著正相关,可作为衡量土壤肥力的指标。

英文摘要：

Four different types of grasslands（alpine meadow,alpine shrub,swamp meadow,mountain steppe） on the eastern Tibetan Plateau were analyzed for variation of soil physicochemical characteristics（soil moisture,pH,organic carbon,total nitrogen）,soil enzyme activity（β-glucosidase,acid phosphatase,urease） and the inter-relationship among them.Soil enzyme activities in the upper soil layer（0-15 cm） were higher than those in the lower layer（15-30 cm）,and the trend was consistent with the four types of grasslands,which indicated that soil biochemical reactions in the upper soil layer were stronger than those in the lower layer.Activities in the four different types of grasslands were in the order： Soil β-glucosidase-swamp meadowalpine shrubalpine meadowmountain steppe;acid phosphatase activities-swamp meadowalpine meadowalpine shrubmountain steppe;urease activities in the upper soil layer-swamp meadowalpine shrubmountain steppealpine meadow,and in the lower soil layer-mountain steppeswap meadowalpine shrubalpine meadow.Soil enzyme activities in swamp meadow were generally higher than in the other three types of grasslands,which indicated that higher primary production in swamp meadow provides more carbon and nitrogen sources for the growth of microorganisms.Correlation analysis indicated that soil urease activity had a significant positive correlation with total nitrogen;soil β-glucosidase activity and acid phosphatase activity had a significant positive correlation with soil organic carbon and total nitrogen.They can therefore be used as indicators of soil fertility.