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Abstract Climate‐driven ecosystem shifts occur through turnover in the foundation species which structure the landscape. Therefore, to predict the fate of areas undergoing climate‐driven ecosystem shifts, one approach is to characterize ecological and evolutionary responses of foundation species along dynamic environmental gradients. One such gradient is the ecotone between tidal marshes and maritime forests in coastal areas of the US Mid‐Atlantic region where accelerated sea‐level rise and coastal storms of increased frequency and intensity are driving forest dieback and inland marsh migration. Mid‐Atlantic tidal marshes are structured by marsh grasses which act as foundation species, and these grasses exhibit trait variation across their distribution from established marsh interior to their inland migration front. We conducted a reciprocal transplant experiment withSpartina patens, a dominant high marsh grass and foundation species, between established populations in the high marsh and range edge populations in the forest understory at three Mid‐Atlantic sites. We monitored environmental conditions in marsh and forest understory habitats, measured plant traits (above‐ and belowground biomass, specific leaf area, leaf N and C concentrations) in transplanted and reference non‐transplanted individuals, and used microsatellite markers to determine the genetic identity of transplants to quantify clonality between habitats and sites. Individuals transplanted into the forest understory exhibited a plastic shift in resource allocation to aboveground structures associated with light acquisition, with shifts in transplants making them more morphologically similar to reference individuals sampled from the forest habitat. Clonal diversity and genetic distance among transplants were relatively high at two of three sites, but individuals at all sites exhibited trans‐habitat plasticity regardless of clonal diversity or a lack thereof. Individuals grown in the forest understory showed lower vegetative and reproductive fitness. Nevertheless, the trait plasticity exhibited by this species allowed individuals from the forest that were transplanted into the marsh to recoup significant biomass in only a single growing season. We predict high plasticity will facilitate the persistence of colonizingS. patensindividuals under suboptimal forest shade conditions until forest dieback increases light availability, ultimately promoting continued inland migration of this foundation species under sea‐level rise.
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Mimicry of emergent traits amplifies coastal restoration success
Abstract Restoration is becoming a vital tool to counteract coastal ecosystem degradation. Modifying transplant designs of habitat-forming organisms from dispersed to clumped can amplify coastal restoration yields as it generates self-facilitation from emergent traits, i.e. traits not expressed by individuals or small clones, but that emerge in clumped individuals or large clones. Here, we advance restoration science by mimicking key emergent traits that locally suppress physical stress using biodegradable establishment structures. Experiments across (sub)tropical and temperate seagrass and salt marsh systems demonstrate greatly enhanced yields when individuals are transplanted within structures mimicking emergent traits that suppress waves or sediment mobility. Specifically, belowground mimics of dense root mats most facilitate seagrasses via sediment stabilization, while mimics of aboveground plant structures most facilitate marsh grasses by reducing stem movement. Mimicking key emergent traits may allow upscaling of restoration in many ecosystems that depend on self-facilitation for persistence, by constraining biological material requirements and implementation costs.
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- Award ID(s):
- 1832178
- PAR ID:
- 10312750
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 11
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1038/s41467-020-17438-4
