A keystone mutualism underpins resilience of a coastal ecosystem to drought.

Published

Journal Article

Droughts are increasing in severity and frequency, yet the mechanisms that strengthen ecosystem resilience to this stress remain poorly understood. Here, we test whether positive interactions in the form of a mutualism between mussels and dominant cordgrass in salt marshes enhance ecosystem resistance to and recovery from drought. Surveys spanning 250 km of southeastern US coastline reveal spatially dispersed mussel mounds increased cordgrass survival during severe drought by 5- to 25-times. Surveys and mussel addition experiments indicate this positive effect of mussels on cordgrass was due to mounds enhancing water storage and reducing soil salinity stress. Observations and models then demonstrate that surviving cordgrass patches associated with mussels function as nuclei for vegetative re-growth and, despite covering only 0.1-12% of die-offs, markedly shorten marsh recovery periods. These results indicate that mutualisms, in supporting stress-resistant patches, can play a disproportionately large, keystone role in enhancing ecosystem resilience to climatic extremes.

Full Text

Duke Authors

Cited Authors

  • Angelini, C; Griffin, JN; van de Koppel, J; Lamers, LPM; Smolders, AJP; Derksen-Hooijberg, M; van der Heide, T; Silliman, BR

Published Date

  • August 18, 2016

Published In

Volume / Issue

  • 7 /

Start / End Page

  • 12473 -

PubMed ID

  • 27534803

Pubmed Central ID

  • 27534803

Electronic International Standard Serial Number (EISSN)

  • 2041-1723

International Standard Serial Number (ISSN)

  • 2041-1723

Digital Object Identifier (DOI)

  • 10.1038/ncomms12473

Language

  • eng