封育和放牧对高寒草甸植被群落特征和土壤特性的影响

为探究封育和放牧对高寒草甸植被群落和土壤特性的影响，本研究以封育13年和连续放牧高寒草甸为研究对象，采用野外群落调查和室内土壤分析相结合的方法，探究封育和放牧对植被群落状况和土壤特性的影响。结果表明：封育显著提高了群落的盖度和地上生物量（P<0.01）；封育显著提高了0~30 cm土壤总氮（Total nitrogen，TN）、速效氮（Available nitrogen，AN）、速效磷（Available phosphorus，AP）和速效钾（Available potassium，AK）（P<0.01）；封育显著降低了群落密度、物种丰富度指数、香农-维纳多样性指数和均匀度指数（P<0.01）。总之，封育虽增加了高寒草甸植物群落生物量和土壤养分，但在一定程度上导致草地植物群落多样性的下降，研究建议针对封育13年的高寒草甸进行适当的放牧以增加群落物种多样性和丰富度。

Effects of Fencing and Grazing on Vegetation Community Characteristics and Soil Properties in An Alpine Meadow

In order to explore the effects of fencing and grazing on the vegetation community and soil characteristics of alpine meadow, this study took 13 years of fenced and continuously grazed alpine meadow as the research objects, and used the methods of field community investigation and indoor soil analysis. The results showed that:Fencing significantly increased community coverage and aboveground biomass (P<0.01);Fencing significantly increased total nitrogen (TN), available nitrogen (AN), available phosphorus (AP) and available potassium (AK) in 0~30 cm soil (P<0.01) when compared to grazing;Fencing significantly reduced community density, species richness index, Shannon-Wiener diversity index and evenness index (P<0.01) in comparison with grazing. In a word, although fencing increased the biomass and soil nutrients of alpine meadow plant community, it caused the decline of grassland plant community diversity to a certain extent. The study suggested that appropriate grazing should be carried out for the alpine meadow that has been fenced for 13 years to increase the species diversity and richness of the community.