Max Planck Institute for Terrestrial Microbiology, Marburg, Germany.
FEMS Microbiol Ecol. 2009 Dec;70(3):377-87. doi: 10.1111/j.1574-6941.2009.00732.x. Epub 2009 Jul 23.
To explore potential links between plant communities, soil denitrifiers and denitrifier function, the impact of presence, diversity (i.e. species richness) and plant combination on nirK-type denitrifier community composition and on denitrifier activity was studied in artificial grassland plant assemblages over two consecutive years. Mesocosms containing zero, four and eight species and different combinations of two species were set up. Differences in denitrifier community composition were analysed by canonical correspondence analyses following terminal restriction fragment length polymorphism analysis of PCR-amplified nirK gene fragments coding for the copper-containing nitrite reductase. As a measure of denitrifier function, denitrifier enzyme activity (DEA) was determined in the soil samples. The presence as well as the combination of plants and sampling time, but not plant diversity, affected the composition of the nirK-type denitrifier community and DEA. Denitrifier activity significantly increased in the presence of plants, especially when they were growing during summer and autumn. Overall, we found a strong and direct linkage of denitrifier community composition and functioning, but also that plants had additional effects on denitrifier function that could not be solely explained by their effects on nirK-type denitrifier community composition.
为了探索植物群落、土壤反硝化菌和反硝化功能之间的潜在联系，本研究在连续两年的人工草地植物组合中，研究了存在、多样性（即物种丰富度）和植物组合对 nirK 型反硝化菌群落组成和反硝化菌活性的影响。在含有零、四和八种物种以及两种不同组合的微宇宙中设置了实验。通过对 PCR 扩增的铜结合亚硝酸盐还原酶编码 nirK 基因片段的末端限制性片段长度多态性分析，采用典范对应分析对反硝化菌群落组成的差异进行了分析。作为反硝化功能的衡量指标，在土壤样品中测定了反硝化酶活性（DEA）。植物的存在及其组合以及采样时间，但不是植物多样性，影响了 nirK 型反硝化菌群落和 DEA 的组成。反硝化菌活性在植物存在的情况下显著增加，特别是在夏季和秋季生长时。总的来说，我们发现反硝化菌群落组成和功能之间存在着强烈而直接的联系，但植物对反硝化菌功能的影响不能仅仅用它们对 nirK 型反硝化菌群落组成的影响来解释。
