放牧强度对克氏针茅草原的土壤酶活性和养分影响

以内蒙古呼伦贝尔的克氏针茅(Stipa krylovii)典型草原作为研究对象,研究轻、中、重三种放牧强度对草地土壤养分和土壤酶活性的影响和相互作用, 旨在为克氏针茅草原生态系统的保护、恢复及重建提供科学依据。结果表明: 土壤养分含量显著降低(P<0.01); 随着放牧强度的增加,过氧化氢酶和蔗糖酶均显著降低(P<0.05),而对脱氢酶和磷酸酶无显著差异(P>0.05)。相关分析表明, 土壤酶活性与土壤养分含量密切相关, 放牧干扰条件下土壤中有效磷与土壤脲酶、过氧化氢酶、蔗糖酶和磷酸酶粒脲酶活性呈显著相关(P<0.05)。

Effects of Grazing Intensities on Soil Enzyme Activities and Nutrient in Stipa Krylovii Steppe

Taking Stipa krylovii typical steppe in Hulunbuir of Inner Mongolia as test objects, the effects of different grazing intensities on soil enzyme activities and chemical properties were studied, aiming to provide scientific basis for protection, restoration and reconstruction of Stipa krylovii. The results showed the soil nutrients reduced significantly (P<0.01) along with the increasing of grazing intensity. The activities of soil catalase and sucrase enzymes all reduced significantly (P<0.05)with the increasing of grazing intensity, but there was no significant difference between soil phosphatase and dehydrogenase enzyme activities (P>0. 05). The results of correlation analysis showed that soil enzyme activities was closely related to soil nutrient contents, and soil available phosphorus content and soil urease, catalase, sucrase and phosphatase activities in grazing disturbance conditions were significantly correlated (P <0.05).