Dataset Information

Seeds of change: characterizing the soil seed bank of a migrating salt marsh.

ABSTRACT:

Background and aims

The capacity for dispersal to promote or hinder species' responses to global change remains a major question in ecology. One ecosystem experiencing rapid change is the tidal marsh, which is migrating inland in response to accelerated sea level rise. Few studies to date have investigated the ecological dynamics that impact this large-scale migration. Seed dispersal and persistence in the soil seed bank is a component that can be strongly indicative of community trajectories. With this in mind, the aim of our study was to characterize the germinable seed bank across a marsh-forest ecotone in the Chesapeake Bay.

Methods

Soil samples were collected across transects that ran from the high marsh to the coastal loblolly pine forest in a brackish marsh in Blackwater National Wildlife Refuge, MD, USA. Samples were grown in a greenhouse and watered with either freshwater or 3 ppt seawater solution. We compared community composition across transects and between salinity treatments. Additionally, we compared the seed bank with standing vegetation and used seed trait data from the TRY Database to investigate changes in functional traits along this ecotone.

Key results

We found halophytic species dispersing up to 15 m into the forest and a general lack of obligate upland species, including near absence of Pinus taeda, the dominant species in the forest canopy. A majority of species detected in the seed bank were wetland species of various types, with species with wide salinity tolerance arising most frequently. Salinity addition had a significant negative influence on seed bank diversity.

Conclusion

Overall, our seed bank results suggest that dispersal and germination under the conditions of saltwater intrusion will limit forest regeneration and favour marsh plant dispersal. This indicates that the ecological processes that determine the soil seed bank community will support continued migration of marsh species into uplands.

SUBMITTER: Kottler EJ

PROVIDER: S-EPMC7442344 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

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Publications

Seeds of change: characterizing the soil seed bank of a migrating salt marsh.

Kottler Emily J EJ Gedan Keryn K

Annals of botany 20200201 2

<h4>Background and aims</h4>The capacity for dispersal to promote or hinder species' responses to global change remains a major question in ecology. One ecosystem experiencing rapid change is the tidal marsh, which is migrating inland in response to accelerated sea level rise. Few studies to date have investigated the ecological dynamics that impact this large-scale migration. Seed dispersal and persistence in the soil seed bank is a component that can be strongly indicative of community traject ...[more]

PMID: 31408516

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Dataset Information

Seeds of change: characterizing the soil seed bank of a migrating salt marsh.

Background and aims

Methods

Key results

Conclusion

Publications

Seeds of change: characterizing the soil seed bank of a migrating salt marsh.

Similar Datasets

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