title: Metagenomic and functional analyses of the consequences of reduction of bacterial diversity on soil functions and bioremediation in diesel-contaminated microcosms.
abstract: The relationship between microbial biodiversity and soil function is an important issue in ecology, yet most studies have been performed in pristine ecosystems. Here, we assess the role of microbial diversity in ecological function and remediation strategies in diesel-contaminated soils. Soil microbial diversity was manipulated using a removal by dilution approach and microbial functions were determined using both metagenomic analyses and enzymatic assays. A shift from Proteobacteria- to Actinobacteria-dominant communities was observed when species diversity was reduced. Metagenomic analysis showed that a large proportion of functional gene categories were significantly altered by the reduction in biodiversity. The abundance of genes related to the nitrogen cycle was significantly reduced in the low-diversity community, impairing denitrification. In contrast, the efficiency of diesel biodegradation was increased in the low-diversity community and was further enhanced by addition of red clay as a stimulating agent. Our results suggest that the relationship between microbial diversity and ecological function involves trade-offs among ecological processes, and should not be generalized as a positive, neutral, or negative relationship.
authors.affiliation: Laboratory of Molecular Environmental Microbiology, Department of Environmental Science and Ecological Engineering, Korea University, Seoul, 02841, Republic of Korea.
authors.forename: Jaejoon
authors.initials: J
authors.lastname: Jung
authors.affiliation: INRA Dijon, UMR 1347 Agroecologie, Dijon, France.
authors.forename: Laurent
authors.initials: L
authors.lastname: Philippot
authors.affiliation: Laboratory of Molecular Environmental Microbiology, Department of Environmental Science and Ecological Engineering, Korea University, Seoul, 02841, Republic of Korea.
authors.forename: Woojun
authors.initials: W
authors.lastname: Park
mesh_terms: D000473:Alkanes / Q000378:metabolism; D001419:Bacteria / Q000145:classification / Q000235:genetics* / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D001673:Biodegradation, Environmental; D044822:Biodiversity; D058440:Denitrification; D017753:Ecosystem; D052918:Environmental Restoration and Remediation / Q000379:methods; D005742:Gasoline; D014644:Genetic Variation; D056186:Metagenomics / Q000379:methods*; D058458:Nitrogen Cycle; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012987:Soil / Q000737:chemistry*; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000378:metabolism
chemical_list: D000473:Alkanes; D001426:Bacterial Proteins; D005742:Gasoline; D012336:RNA, Ribosomal, 16S; D012987:Soil; D012989:Soil Pollutants