典型草原恢复演替过程中土壤微生物及酶活性动态变化研究

Dynamics of Soil Microorganism and Enzyme Activity in Typical Steppe of Restoration Succession Process

选取不同围封年限的生长季围封恢复草地为研究对象,开展典型草原恢复演替过程中土壤微生物及酶活性动态变化的研究,探讨土壤微生物及酶活性与草地植被及土壤养分的相关性。结果表明:与自由放牧草地相比,围封7年、10年、13年和20年的草地,其土壤0～30cm土层细菌、放线菌和真菌数量显著增加,土壤转化酶、脲酶、蛋白酶和过氧化氢酶活性增强,土壤微生物量碳、氮含量显著增加(P<0.05),且随围封年限的延长呈增加的变化趋势。典型草原恢复演替过程中土壤微生物及酶活性与草地植被及土壤养分呈基本一致的变化规律,三者成密切的正相关关系。

Natural grasslands were enclosed during growing seasons for selected years as research objects.Dynamics of soil microorganisms and enzyme activities in typical steppe during restoration processes were studied for discussing correlations among soil microorganisms,enzyme activities,vegetation characteristics and soil nutrients.Results showed that the number of soil bacteria,actinomycetes and fungi increased,soil enzyme activity enhanced,and soil microbial biomass C,N increased significantly(P<0.05) in 0~30 cm soil layer after 7,10,13 and 20 years enclosure compared with continuous grazing and increased gradually with enclosure period increasing.The change of soil microorganism and enzyme activity in typical steppe during restoring processes was basically identical with the change of vegetation characteristics and soil nutrient which showed a positive correlation.