放牧改变了藏北高原高寒草甸土壤微生物群落

发布时间：2019-07-04 08:12

【摘要】：本研究基于2008年7月布设的3个围栏与自由放牧样地(一个高寒草原化草甸,冬季牧场;一个高寒草原化草甸,夏季牧场;一个典型高寒草甸,夏季牧场),开展了藏北高原高寒草甸土壤微生物群落组成对放牧的响应研究。土壤微生物群落组成采用磷脂脂肪酸方法(phospholipid fatty-acid,PLFA)测定。结果表明,冬季放牧显著降低了高寒草原化草甸的土壤真菌、革兰氏阴性细菌、放线菌和原生动物。夏季放牧显著降低了典型高寒草甸的土壤总PLFA、真菌、细菌、革兰氏阳性细菌、革兰氏阴性细菌、放线菌、丛枝菌根真菌和原生动物。基于冗余度分析,3个放牧与围栏条件下的土壤微生物群落组成都存在显著差异。土壤无机氮和水溶性有机氮显著影响着高寒草原化草甸冬季牧场的土壤微生物群落组成,而硝态氮和水溶性有机碳显著影响着高寒草原化草甸夏季牧场和典型高寒草甸夏季牧场的土壤微生物群落组成。因此,放牧对高寒草甸土壤微生物群落的影响与放牧季节和草地类型有关。
[Abstract]:Based on three fences and free grazing plots (one alpine meadow, winter meadow, one alpine meadow, summer rangeland, one typical alpine meadow, summer rangeland) in July 2008, the response of soil microbial community composition to grazing in alpine meadow in northern Tibet was studied. The composition of soil microbial community was determined by phospholipid fatty acid method (phospholipid fatty-acid,PLFA). The results showed that winter grazing significantly reduced soil fungi, Gram-negative bacteria, actinomycetes and protozoa in alpine meadow. Summer grazing significantly reduced total PLFA, fungi, bacteria, Gram-positive bacteria, Gram-negative bacteria, actinomycetes, arbuscular mycorrhizal fungi and protozoa in typical alpine meadows. Based on redundancy analysis, there were significant differences in soil microbial community composition between the three grazing and fenced conditions. Soil inorganic nitrogen and water-soluble organic nitrogen significantly affected the soil microbial community composition of alpine meadow in winter, while nitrate nitrogen and water-soluble organic carbon significantly affected the soil microbial community composition of alpine meadow summer meadow and typical alpine meadow summer meadow. Therefore, the effect of grazing on soil microbial community in alpine meadow is related to grazing season and grassland type.
【作者单位】：中国科学院地理科学与资源研究所生态系统网络观测与模拟重点实验室拉萨高原生态系统研究站;
【基金】：国家自然基金项目(31600432,41171084) 国家重点研发计划(2016YFC0502005,2016YFC0502006)资助
【分类号】：S812.2

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