Azarbad Hamed, Niklińska Maria, Laskowski Ryszard, van Straalen Nico M, van Gestel Cornelis A M, Zhou Jizhong, He Zhili, Wen Chongqing, Röling Wilfred F M
Institute of Environmental Sciences, Jagiellonian University, Gronostajowa 7, 30-387 Krakow, Poland
Institute of Environmental Sciences, Jagiellonian University, Gronostajowa 7, 30-387 Krakow, Poland.
FEMS Microbiol Ecol. 2015 Jan;91(1):1-11. doi: 10.1093/femsec/fiu003. Epub 2014 Dec 5.
Despite the global importance of forests, it is virtually unknown how their soil microbial communities adapt at the phylogenetic and functional level to long-term metal pollution. Studying 12 sites located along two distinct gradients of metal pollution in Southern Poland revealed that functional potential and diversity (assessed using GeoChip 4.2) were highly similar across the gradients despite drastically diverging metal contamination levels. Metal pollution level did, however, significantly impact bacterial community structure (as shown by MiSeq Illumina sequencing of 16S rRNA genes), but not bacterial taxon richness and community composition. Metal pollution caused changes in the relative abundance of specific bacterial taxa, including Acidobacteria, Actinobacteria, Bacteroidetes, Chloroflexi, Firmicutes, Planctomycetes and Proteobacteria. Also, a group of metal-resistance genes showed significant correlations with metal concentrations in soil. Our study showed that microbial communities are resilient to metal pollution; despite differences in community structure, no clear impact of metal pollution levels on overall functional diversity was observed. While screens of phylogenetic marker genes, such as 16S rRNA genes, provide only limited insight into resilience mechanisms, analysis of specific functional genes, e.g. involved in metal resistance, appears to be a more promising strategy.
尽管森林具有全球重要性，但实际上人们对其土壤微生物群落在系统发育和功能水平上如何适应长期金属污染却知之甚少。对波兰南部沿两个不同金属污染梯度分布的12个地点进行研究发现，尽管金属污染水平差异巨大，但各梯度间的功能潜力和多样性（使用GeoChip 4.2评估）高度相似。然而，金属污染水平确实对细菌群落结构有显著影响（如通过对16S rRNA基因进行Illumina MiSeq测序所示），但对细菌分类单元丰富度和群落组成没有影响。金属污染导致特定细菌分类群的相对丰度发生变化，包括酸杆菌门、放线菌门、拟杆菌门、绿弯菌门、厚壁菌门、浮霉菌门和变形菌门。此外，一组金属抗性基因与土壤中的金属浓度呈现显著相关性。我们的研究表明，微生物群落对金属污染具有恢复力；尽管群落结构存在差异，但未观察到金属污染水平对整体功能多样性有明显影响。虽然对系统发育标记基因（如16S rRNA基因）的筛选仅能有限地洞察恢复力机制，但对特定功能基因（如参与金属抗性的基因）的分析似乎是一种更有前景的策略。
