title: Environmental and plant community determinants of species loss following nitrogen enrichment.
abstract: Global energy use and food production have increased nitrogen inputs to ecosystems worldwide, impacting plant community diversity, composition, and function. Previous studies show considerable variation across terrestrial herbaceous ecosystems in the magnitude of species loss following nitrogen (N) enrichment. What controls this variation remains unknown. We present results from 23 N-addition experiments across North America, representing a range of climatic, soil and plant community properties, to determine conditions that lead to greater diversity decline. Species loss in these communities ranged from 0 to 65% of control richness. Using hierarchical structural equation modelling, we found greater species loss in communities with a lower soil cation exchange capacity, colder regional temperature, and larger production increase following N addition, independent of initial species richness, plant productivity, and the relative abundance of most plant functional groups. Our results indicate sensitivity to N addition is co-determined by environmental conditions and production responsiveness, which overwhelm the effects of initial community structure and composition.
authors.affiliation: Department of Ecology, Evolution and Behavior, University of Minnesota, St Paul, MN 55108, USA. clark134@umn.edu
authors.forename: Chris M
authors.initials: CM
authors.lastname: Clark
authors.forename: Elsa E
authors.initials: EE
authors.lastname: Cleland
authors.forename: Scott L
authors.initials: SL
authors.lastname: Collins
authors.forename: Joseph E
authors.initials: JE
authors.lastname: Fargione
authors.forename: Laura
authors.initials: L
authors.lastname: Gough
authors.forename: Katherine L
authors.initials: KL
authors.lastname: Gross
authors.forename: Steven C
authors.initials: SC
authors.lastname: Pennings
authors.forename: Katherine N
authors.initials: KN
authors.lastname: Suding
authors.forename: James B
authors.initials: JB
authors.lastname: Grace
mesh_terms: D044822:Biodiversity; D005308:Fertilizers; D008954:Models, Biological; D009584:Nitrogen; D009656:North America; D063245:Plant Development; D012987:Soil / Q000032:analysis*; D013045:Species Specificity; D013696:Temperature
chemical_list: D005308:Fertilizers; D012987:Soil; D009584:Nitrogen