title: Function-specific response to depletion of microbial diversity.
abstract: Recent meta-analyses suggest that ecosystem functioning increases with biodiversity, but contradictory results have been presented for some microbial functions. Moreover, observations of only one function underestimate the functional role of diversity because of species-specific trade-offs in the ability to carry out different functions. We examined multiple functions in batch cultures of natural freshwater bacterial communities with different richness, achieved by a dilution-to-extinction approach. Community composition was assessed by molecular fingerprinting of 16S rRNA and chitinase genes, representing the total community and a trait characteristic for a functional group, respectively. Richness was positively related to abundance and biomass, negatively correlated to cell volumes and unrelated to maximum intrinsic growth rate. The response of chitin and cellulose degradation rates depended on the presence of a single phylotype. We suggest that species identity and community composition rather than richness matters for specific microbial processes.
authors.affiliation: Department of Limnology, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden. hannes.peter@ebc.uu.se
authors.forename: Hannes
authors.initials: H
authors.lastname: Peter
authors.forename: Sara
authors.initials: S
authors.lastname: Beier
authors.forename: Stefan
authors.initials: S
authors.lastname: Bertilsson
authors.forename: Eva S
authors.initials: ES
authors.lastname: Lindström
authors.forename: Silke
authors.initials: S
authors.lastname: Langenheder
authors.forename: Lars J
authors.initials: LJ
authors.lastname: Tranvik
mesh_terms: D001419:Bacteria / Q000201:enzymology* / Q000235:genetics* / Q000254:growth & development; D044822:Biodiversity; D018533:Biomass; D002482:Cellulose / Q000378:metabolism; D002686:Chitin / Q000378:metabolism; D002688:Chitinases / Q000235:genetics; D016172:DNA Fingerprinting; D005618:Fresh Water / Q000382:microbiology*; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D014871:Water Microbiology
chemical_list: D012336:RNA, Ribosomal, 16S; D002686:Chitin; D002482:Cellulose; D002688:Chitinases