Species traits and environmental conditions govern the relationship between biodiversity effects across trophic levels.
Oecologia
; 168(2): 533-48, 2012 Feb.
Article
em En
| MEDLINE
| ID: mdl-21901360
ABSTRACT
Changing environments can have divergent effects on biodiversity-ecosystem function relationships at alternating trophic levels. Freshwater mussels fertilize stream foodwebs through nutrient excretion, and mussel species-specific excretion rates depend on environmental conditions. We asked how differences in mussel diversity in varying environments influence the dynamics between primary producers and consumers. We conducted field experiments manipulating mussel richness under summer (low flow, high temperature) and fall (moderate flow and temperature) conditions, measured nutrient limitation, algal biomass and grazing chironomid abundance, and analyzed the data with non-transgressive overyielding and tripartite biodiversity partitioning analyses. Algal biomass and chironomid abundance were best explained by trait-independent complementarity among mussel species, but the relationship between biodiversity effects across trophic levels (algae and grazers) depended on seasonal differences in mussel species' trait expression (nutrient excretion and activity level). Both species identity and overall diversity effects were related to the magnitude of nutrient limitation. Our results demonstrate that biodiversity of a resource-provisioning (nutrients and habitat) group of species influences foodweb dynamics and that understanding species traits and environmental context are important for interpreting biodiversity experiments.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Bivalves
/
Cadeia Alimentar
/
Biodiversidade
Limite:
Animals
Idioma:
En
Revista:
Oecologia
Ano de publicação:
2012
Tipo de documento:
Article
País de afiliação:
Estados Unidos