Abundances and potential activities of nitrogen cycling microbial communities along a chronosequence of a glacier forefield
Abundances and potential activities of nitrogen cycling microbial communities along a chronosequence of a glacier forefield
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DOI：
10.1038/ismej.2010.184
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发表时间：
2011-06-01
期刊：
影响因子：
11
通讯作者：
Zeyer, Josef
中科院分区：
文献类型：
--
作者：
Brankatschk, Robert;Toewe, Stefanie;Zeyer, Josef
冰川前田是研究土壤养分循环和单次周转过程的理想生态系统。在这项研究中，我们研究了生态学的微生物氮（N）循环散装土壤样品从瑞士达玛冰川的年代序列。氮循环的主要过程进行了重建的遗传以及潜在的酶活性水平在网站的时间序列，已无冰10，50，70，120和2000年。在我们的研究中，我们集中在固氮，矿化（几丁质酶和蛋白酶），硝化和反硝化。我们的研究结果表明，矿化，主要是沉积的有机物质的分解，是在初始土壤中，也就是说，无冰10年的氮周转的主要驱动力。瞬态土壤是无冰的50和70年的特点是高丰度的固氮微生物。在发达的土壤中，无冰120年和2000年，显着的硝化和反硝化速率进行了测量。令人惊讶的是，在土壤发育的初始阶段，编码相应酶的相应功能基因的拷贝数已经很高。这清楚地表明，在土壤形成的初始阶段，遗传潜力不是某些功能性状的驱动因素，而是编码选定功能的相应基因的良好平衡表达。The ISME Journal（2011）5，1025-1037; doi：10.1038/ismej.2010.184; 2010年12月2日在线发表
Glacier forefields are ideal ecosystems to study the development of nutrient cycles as well as single turnover processes during soil development. In this study, we examined the ecology of the microbial nitrogen (N) cycle in bulk soil samples from a chronosequence of the Damma glacier, Switzerland. Major processes of the N cycle were reconstructed on the genetic as well as the potential enzyme activity level at sites of the chronosequence that have been ice-free for 10, 50, 70, 120 and 2000 years. In our study, we focused on N fixation, mineralization (chitinolysis and proteolysis), nitrification and denitrification. Our results suggest that mineralization, mainly the decomposition of deposited organic material, was the main driver for N turnover in initial soils, that is, ice-free for 10 years. Transient soils being ice-free for 50 and 70 years were characterized by a high abundance of N fixing microorganisms. In developed soils, ice-free for 120 and 2000 years, significant rates of nitrification and denitrification were measured. Surprisingly, copy numbers of the respective functional genes encoding the corresponding enzymes were already high in the initial phase of soil development. This clearly indicates that the genetic potential is not the driver for certain functional traits in the initial phase of soil formation but rather a well-balanced expression of the respective genes coding for selected functions. The ISME Journal (2011) 5, 1025-1037; doi:10.1038/ismej.2010.184; published online 2 December 2010 Subject Category: geomicrobiology and microbial contributions to geochemical cycles