藏北高寒草地土壤磷脂脂肪酸指纹特征及其与土壤化学性质的关系

发布时间：2018-02-21 18:39

本文关键词： 土壤微生物磷脂脂肪酸高寒草地土壤有机碳硝态氮铵态氮　出处：《生态环境学报》2017年09期 　论文类型：期刊论文

【摘要】：微生物是土壤的重要组成部分,反映了土壤的生物活性,同时也是土壤有机质和养分转化与循环的动力。高寒草地是藏北高原分布面积最大的生态系统类型,不仅是亚洲中部高寒环境中最为典型的自然生态系统之一,而且在世界高寒地区亦具有代表性。为了解藏北不同类型高寒草地土壤微生物群落结构特征,比较了藏北5种高寒草地(高寒草甸、高寒草原、高寒草甸草原、高寒荒漠草原和高寒荒漠)的土壤磷脂脂肪酸(PLFA)指纹特征,并进一步分析其与土壤有机碳、总氮等土壤化学性质的关系。藏北5种高寒草地土壤PLFA中16:0和18:1w9c含量高,土壤PLFA主要包括直链饱和脂肪酸、直链单不饱和脂肪酸、支链饱和脂肪酸和环丙烷脂肪酸,其中直链单不饱和脂肪酸(27.77%~36.66%)和支链饱和脂肪酸(30.15%~36.61%)占比较高,环丙烷脂肪酸(3.48%~10.16%)仅占较少部分。高寒草甸土壤总PLFA含量、细菌、真菌、放线菌、革兰氏阴性菌和革兰氏阳性菌PLFA含量最高,其含量分别是其他4种草地类型土壤的2.00~6.45,2.01~8.88,1.82~3.52,1.61~5.37,2.01~9.17和2.06~10.94倍。大部分PLFA分子集中于高寒草甸、高寒草原和高寒草甸草原土壤中,另外两种高寒草地土壤仅含少量微生物;土壤微生物在5种类型草地中的样点基本分散,而在每种类型草地样点中基本集中,表明微生物群落结构在不同草地类型土壤中存在明显差异,而在同一类型草地土壤中相近。土壤总PLFA,细菌、真菌、放线菌、革兰氏阴性细菌和革兰氏阳性细菌PLFA含量与土壤有机碳、总氮、铵态氮和硝态氮之间存在极显著相关性(P0.01),表明土壤碳、氮含量与土壤微生物间存在极为显著的相互刺激关系。该研究通过量化藏北不同类型高寒草地土壤的PLFA指纹特征,并分析其与土壤化学性质的关系,为进一步研究高寒草地生态系统土壤微生物群落结构特征提供理论依据。
[Abstract]:Microorganism is an important part of soil, which reflects the biological activity of soil, and is also the motive force of soil organic matter and nutrient transformation and circulation. Alpine grassland is the largest ecosystem type in the northern Tibetan Plateau. Not only is it one of the most typical natural ecosystems in the alpine environment of central Asia, but also it is representative in the cold regions of the world. In order to understand the soil microbial community structure of different types of alpine grassland in northern Tibet, The fingerprint characteristics of phospholipid fatty acids (PLFAs) in five alpine grasslands (alpine meadow, alpine steppe, alpine meadow, alpine desert steppe and alpine desert) in northern Tibet were compared. The relationship between total nitrogen and other soil chemical properties. The contents of PLFA in five kinds of alpine grassland in northern Tibet were 16: 0 and 18: 1w9c. Soil PLFA mainly included straight chain saturated fatty acid, straight chain monounsaturated fatty acid, branched chain saturated fatty acid and cyclopropane fatty acid. The percentage of straight chain monounsaturated fatty acids 27.77 and branched chain saturated fatty acids 30.15 and 36.61) is relatively high, while that of cyclopropane fatty acids is 3.48 and 10.16). The total PLFA content, bacteria, fungi, actinomycetes in alpine meadow soils, The PLFA content of Gram-negative bacteria and Gram-positive bacteria was the highest in the other four grassland types, and the content of PLFA was 2.006.45.2.01, 8.882, 1.82, 3.52, 1.61, 5.37, 2.01 and 10.94 times, respectively. Most of PLFA molecules were concentrated in alpine meadow, alpine steppe and alpine meadow grassland, and most of the PLFA molecules were found in alpine meadow, alpine steppe and alpine meadow steppe, respectively, and most of PLFA molecules were found in alpine meadow, alpine steppe and alpine meadow steppe. The other two alpine grassland soils contain only a small amount of microbes, and the soil microbes are basically dispersed in the five types of grasslands, while they are basically concentrated in the samples of each type of grassland. The results showed that there were significant differences in the structure of microbial community in different grassland types, but similar in the same type of grassland soil, the total PLFA, bacteria, fungi, actinomycetes, fungi, actinomycetes, bacteria, fungi, actinomycetes, The PLFA content of Gram-negative bacteria and Gram-positive bacteria was significantly correlated with soil organic carbon, total nitrogen, ammonium nitrogen and nitrate nitrogen, indicating that soil carbon. The relationship between nitrogen content and soil microbes was highly significant. This study analyzed the relationship between nitrogen content and soil chemical properties by quantifying the PLFA fingerprint characteristics of different types of alpine grassland soils in northern Tibet. It provides theoretical basis for further study of soil microbial community structure in alpine grassland ecosystem.
【作者单位】：中国科学院水利部成都山地灾害与环境研究所山地表生过程与生态调控重点实验室;中国科学院大学;陕西省灾害监测与机理模拟重点实验室//宝鸡文理学院地理与环境学院;
【基金】：国家自然科学基金项目(41671262;41371267)
【分类号】：S812.2

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