title: Soil functional operating range linked to microbial biodiversity and community composition using denitrifiers as model guild.
abstract: Soil microorganisms are key players in biogeochemical cycles. Yet, there is no consistent view on the significance of microbial biodiversity for soil ecosystem functioning. According to the insurance hypothesis, declines in ecosystem functioning due to reduced biodiversity are more likely to occur under fluctuating, extreme or rapidly changing environmental conditions. Here, we compare the functional operating range, a new concept defined as the complete range of environmental conditions under which soil microbial communities are able to maintain their functions, between four naturally assembled soil communities from a long-term fertilization experiment. A functional trait approach was adopted with denitrifiers involved in nitrogen cycling as our model soil community. Using short-term temperature and salt gradients, we show that the functional operating range was broader and process rates were higher when the soil community was phylogenetically more diverse. However, key bacterial genotypes played an important role for maintaining denitrification as an ecosystem functioning under certain conditions.
authors.affiliation: Swedish University of Agricultural Sciences, Department of Microbiology, Uppsala, Sweden. Sara.Hallin@slu.se
authors.forename: Sara
authors.initials: S
authors.lastname: Hallin
authors.forename: Allana
authors.initials: A
authors.lastname: Welsh
authors.forename: John
authors.initials: J
authors.lastname: Stenström
authors.forename: Stephanie
authors.initials: S
authors.lastname: Hallet
authors.forename: Karin
authors.initials: K
authors.lastname: Enwall
authors.forename: David
authors.initials: D
authors.lastname: Bru
authors.forename: Laurent
authors.initials: L
authors.lastname: Philippot
mesh_terms: D001419:Bacteria / Q000145:classification / Q000235:genetics; D044822:Biodiversity; D017753:Ecosystem; D004777:Environment; D005838:Genotype; D054892:Metagenome / Q000235:genetics; D008962:Models, Theoretical; D010802:Phylogeny; D012492:Salts / Q000737:chemistry; D012987:Soil / Q000737:chemistry; D012988:Soil Microbiology; D013548:Sweden; D013696:Temperature
chemical_list: D012492:Salts; D012987:Soil