【摘要】 以内蒙古短花针茅荒漠草原为对象,对不同载畜率下（轻度放牧、中度放牧、重度放牧）三种土壤酶（脱氢酶、脲酶、碱性磷酸酶）活性进行分析,并探讨植物群落生物量以及土壤pH值、有机质、全氮、全磷含量等环境因子与土壤酶的相互作用。结果表明,三种土壤酶活性随载畜率增加呈降低趋势,脱氢酶活性在禁牧区（197.51μgTPF/g·h）最高,脲酶活性在轻度放牧区（40.64mgNH⁺₄-N/g·h）和重度放牧区（40.78mgNH⁺₄-N/g·h）最高,磷酸酶活性在轻度放牧区（53.93μgphenol/g·h）最高;脱氢酶和脲酶活性在中度和重度放牧区不同土层内有显著差异（P<0.05）,0～10cm土层酶活性高于10～20cm土层;不同载畜率下磷酸酶活性0～10cm土层高于10～20cm;三种酶之间相关性较低,但三种酶皆与环境因子有着密切联系。更多还原

【Abstract】 In order to reveal the changes of soil enzyme activities in desert steppe under different stocking rates, the Stipa breviflora desert steppe in Inner Mongolia was the subject of this experiment. The activities of three soil enzymes（Dehydrogenase, urease and alkaline phosphatase） were analyzed under three different stocking rates（Light grazing, moderate grazing, heavy grazing）, and the interaction between plant communities’ aboveground and underground biomass, soil pH, soil organic matter（SOM）, total nitrogen（TN）, total phosphorus（TP） and other environmental factors and soil enzymes were investigated. The results showed that the activity of three soil enzymes decreased with the increase of stocking rate. The dehydrogenase activity was the highest in CK（197.51μgTPF/g·h）, the urease activity was the highest both in LG（40.64 mgNH⁺₄-N/g·h） and HG（40.78 mgNH⁺₄-N/g·h）, the phosphatase activity was the highest in LG（53.93μgphenol/g·h）. The activities of dehydrogenase and urease were significant difference in different soil layers in MG and HG（P<0.05）, and the enzyme activities in 0～10 cm soil layer was higher than those in 10～20 cm soil layer. The activity of phosphatase in 0～10 cm was higher than that in 10～20 cm soil layer under different stocking rates. There was a low correlation between the three enzymes, but the three enzymes were closely related to environmental factors. Appropriate grazing can not only improve the enzymatic ability of various soil enzymes, but also curb the grassland decline.更多还原