title: Emergence of nutrient co-limitation through movement in stoichiometric meta-ecosystems.
abstract: Evidence that ecosystems and primary producers are limited in their productivity by multiple nutrients has caused the traditional nutrient limitation framework to include multiple limiting nutrients. The models built to mimic these responses have invoked local mechanisms at the level of the primary producers. In this paper, we explore an alternative explanation for the emergence of co-limitation by developing a simple, stoichiometrically explicit meta-ecosystem model with two limiting nutrients, autotrophs and herbivores. Our results show that differences in movement rates for the nutrients, autotrophs and herbivores can allow for nutrient co-limitation in biomass response to emerge despite no local mechanisms of nutrient co-limitation. Furthermore, our results provide an explanation to why autotrophs show positive growth responses to nutrients despite 'nominal' top-down control by herbivores. These results suggest that spatial processes can be mechanisms for nutrient co-limitation at local and regional scales, and can help explain anomalous results in the co-limitation literature.
authors: Department of Biology, McGill University, Montreal, Quebec, Canada.
authors: Justin N
authors: JN
authors: Marleau
authors: Department of Biology, McGill University, Montreal, Quebec, Canada.
authors: Frédéric
authors: F
authors: Guichard
authors: Centre for Biodiversity Theory and Modelling, Experimental Ecology, Centre National de la Recherche Scientifique, 09200, Moulis, France.
authors: Michel
authors: M
authors: Loreau
keywords: Meta-ecosystem; modelling; nutrient co-limitation; spatial ecology; stoichiometry; top-down control