Abstract
Considering their key role for ecosystem processes, it is important to understand the response of microbial communities in unpolluted soils to pollution with polycyclic aromatic hydrocarbons (PAH). Phenanthrene, a model compound for PAH, was spiked to a Cambisol and a Luvisol soil. Total community DNA from phenanthrene-spiked and control soils collected on days 0, 21, and 63 were analyzed based on PCR-amplified 16S rRNA gene fragments. Denaturing gradient gel electrophoresis (DGGE) fingerprints of bacterial communities increasingly deviated with time between spiked and control soils. In taxon specific DGGE, significant responses of Alphaproteobacteria and Actinobacteria became only detectable after 63 days, while significant effects on Betaproteobacteria were detectable in both soils after 21 days. Comparison of the taxonomic distribution of bacteria in spiked and control soils on day 63 as revealed by pyrosequencing indicated soil type specific negative effects of phenanthrene on several taxa, many of them belonging to the Gamma-, Beta-, or Deltaproteobacteria. Bacterial richness and evenness decreased in spiked soils. Despite the significant differences in the bacterial community structure between both soils on day 0, similar genera increased in relative abundance after PAH spiking, especially Sphingomonas and Polaromonas. However, this did not result in an increased overall similarity of the bacterial communities in both soils.
Highlights
Anthropogenic activities such as combustion of wood, coal, and petroleum or mining accidents frequently result in the pollution of soils with polycyclic aromatic hydrocarbons (PAH) which have several potential adverse effects on environments and human health due to their toxicity, persistence, and carcinogenicity (Johnsen et al, 2005; Pumphrey and Madsen, 2007; Schafer et al, 2009)
RESPONSES OF SOIL BACTERIAL COMMUNITIES TO PHENANTHRENE DEPENDING ON SOIL TYPE, EXPOSURE TIME, AND TAXONOMIC GROUP AS REVEALED BY PCR-Denaturing gradient gel electrophoresis (DGGE) Community fingerprints of Bacteria, Pseudomonas, Actinobacteria, Beta, and Alphaproteobacteria were clustered by UPGMA based on Pearson correlation indices
The response to phenanthrene spiking of bacterial communities in two previously unpolluted soils was explored by DGGE and pyrosequencing analysis of 16S rRNA gene fragments amplified from total community (TC) DNA
Summary
Anthropogenic activities such as combustion of wood, coal, and petroleum or mining accidents frequently result in the pollution of soils with polycyclic aromatic hydrocarbons (PAH) which have several potential adverse effects on environments and human health due to their toxicity, persistence, and carcinogenicity (Johnsen et al, 2005; Pumphrey and Madsen, 2007; Schafer et al, 2009). Microbial populations in polluted soils or sediments are very well studied (Gomes et al, 2005, 2007; Leys et al, 2005; Singleton et al, 2005; Ni Chadhain et al, 2006; Zhou et al, 2006; Flocco et al, 2009; Liang et al, 2009). The type of PAH substrates (Singleton et al, 2005; Ni Chadhain et al, 2006; Gray et al, 2011) together with several biotic and abiotic factors, e.g., plant exudates (Sipila et al, 2008; Cebron et al, 2011) or particle sizes of soil minerals (Uyttebroek et al, 2006), were shown to influence the composition and abundance of total or degradative bacterial populations in polluted soils. The dynamics of microbial communities in unpolluted soils which are under the threat of PAH pollutions were only rarely explored
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
