生态恢复模式对若尔盖高寒沙化草地土壤微生物群落功能多样性的影响

Effects of ecological restoration patterns on soil microbial community functional diversity in Zoige alpine desertification grassland

若尔盖高原生态战略地位突出,在维持地区生物多样性、生态系统稳定等方面起到重要作用。研究不同生态恢复模式下土壤微生物群落功能多样性,有助于为在高寒草地以及全国其他类似地区实施退牧还草、退耕还林还草等生态环境重建工作提供科学依据。以若尔盖草地不同恢复模式下的土壤微生物群落为研究对象,采用Biolog微平板法对比研究了生态治理措施对沙化草地生态系统及其土壤微生物功能多样性的影响。结果表明:人工生态恢复模式提高了沙化草地土壤微生物的活性,其中灌草间作模式下的恢复样地与自然恢复样地在稳定时二者的平均颜色变化率差值达到0.761;灌草间作模式下草地土壤微生物群落的Shannon指数、Simpson指数及McIntosh指数分别为3.290、0.960和10.408,均比草地建植模式下高,该模式能为土壤微生物群落提供更多的生态位;灌草间作恢复模式下草地土壤微生物群落利用各类碳源能力较其他恢复模式高,碳水化合物和氨基酸类是若尔盖草地土壤微生物群落利用最多的碳源;采用灌草间作模式的人工治理方式,同时结合增加草地土壤中碳水化合物、氨基酸类等碳源含量的生物措施,可以高效地治理若尔盖高寒沙化草地。

The prominent ecological strategic position of Zoige Plateau plays an important role in maintaining regional biodiversity and ecosystem stability.The study on the functional diversity of soil microbial community under different ecological restoration models is helpful to provide a scientific basis for the ecological environment reconstruction of alpine grassland and other similar regions in China,such as returning grazing to grassland,returning farmland to forest and grassland.The soil microbial community under different restoration modes in Zoige grassland was taken as the research object,and Biolog microplate method was used to compare the effects of ecological management measures on the ecosystem of sandy grassland and the diversity of soil microbial function.The results showed that the artificial ecological restoration model improved the activity of soil microorganisms in the sandy grassland,and the average well color development(AWCD)value of the restoration sample plot under the shrub-grass intercropping mode and the natural restoration sample plot reached 0.761 at stable state.Shannon index,Simpson index and McIntosh index of soil microbial community in the shrub-grass intercropping mode were higher than those in the grassland planting mode,and the index values were 3.290,0.960 and 10.408,respectively.This mode could provide more niches for soil microbial communities.The carbon source capacity of grassland soil microbial community under shrub-grass intercropping restoration mode was higher than that under other restoration modes.Carbohydrates and amino acids were the most used carbon sources in Zoige grassland soil microbial community.The artificial management mode of shrub-grass intercropping combined with the biological measures to increase the carbon sources such as carbohydrates and amino acids in the grassland soil could be used to control the alpine sandy grassland in Zoige more efficiently.