毛乌素沙地放牧和封育对草地植物群落特征的影响

Effects of Grazing and Enclosure on Grassland Plant Community Characteristics in Mu Us Desert

为探究封育和放牧对荒漠草原植被群落特征的影响,以毛乌素沙地南缘宁夏盐池的封育草地和连续放牧草地为研究对象,通过样方调查法进行野外植被调查,探究了封育和放牧对物种多样性、群落特征、地上初级生产力以及对降水和温度的响应。根据2010年、2015年、2020年、2022年的数据可知:封育地内植物丰富度、均匀度、植物种类、群落高度优于放牧地,但放牧地的优势度指数要高于封育区,同时,长期封育不利于植物地上生物量的提高。总之,封育虽增加了荒漠草原植物群落丰富度和均匀度,但在一定程度上导致草地植物生物量和优势度的下降,为此,建议针对封育21年的草地进行适当的利用以增加群落物种优势度和生物量。

In order to investigate the effects of enclosure and grazing on the characteristics of desert grassland vegetation communities,this study took the closed grassland and continuously grazed grassland in Yanchi,Ningxia,at the southern edge of the Mu Us desert as the research object,and conducted field vegetation surveys through the sample survey method to investigate the responses of enclosure and grazing on species diversity,community characteristics,aboveground primary productivity,precipitation and temperature.According to the data of 2010,2015,2020 and 2022,it can be seen that the plant richness,evenness,plant species,and community height in the closed area are better than that in the grazed area,but the dominance index of the grazed area is higher than that of the closed area.At the same time,the long-term enclosure is not conducive to the increase of the aboveground biomass of plants.In conclusion,although sealing increased the richness and evenness of desert grassland plant communities,it led to a certain extent to the decline of grassland plant biomass and dominance,and the study recommended that the grassland that had been sealed for 21 years should be appropriately utilized in order to increase the dominance and biomass of the community species.