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Marsh sediment in translation: A review of sediment transport across a natural tidal salt marsh in northern San Francisco Bay

Madeline R. Foster-Martinez·Matthew C. Ferner·John C. Callaway·Brenda Goeden·Jessica R. Lacy
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Abstract

Deposition of inorganic sediment is essential for the sustainability of tidal salt marshes. Understanding variability in sediment sources and the processes of sediment delivery to salt marshes are high priorities for decision-makers responsible for managing sediment and conserving and restoring marshes. Research on sediment transport to marshes is published in technical journals, but these scientific findings must be translated and communicated to inform critical decisions related to managing sediment in estuaries. We convened a diverse group of collaborators—including natural-resource managers, regulators, scientists, and restoration planners and practitioners—to review and interpret the results of previously published field investigations on and around the salt marsh at China Camp State Park in Marin County, California. We discussed and translated key results of those studies using new graphics and more accessible language. Here, we present a general introduction to the topic of sediment delivery to salt marshes, background descriptions of the China Camp marsh and the physical processes that we characterized there, key scientific conclusions, and proposed management implications. Key conclusions include (1) bay shallows are an important but variable source of marsh sediment, (2) flood tides and waves move sediment across the bay–marsh edge, (3) tidal creeks may not always import sediment to the marsh platform, and (4) protective effects of marsh vegetation depend on species and season. China Camp marsh is one of the last remaining pre-colonial salt marshes in the San Francisco Estuary and is unique in being relatively unmodified by humans and in retaining an unimpeded transition into natural uplands. Additional studies in a variety of marshes with different attributes and sediment regimes will broaden understanding of how best to conserve, manage, and restore tidal marshes that provide numerous ecosystem services to for humans and wildlife.

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San Francisco Estuary and Watershed ScienceArticle
90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 38.002353016236555° to 38.0271888837386° latitude; -122.50282971340158° to -122.41897404654148° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Madeline R. Foster-Martinez, Matthew C. Ferner, John C. Callaway, Brenda Goeden, Jessica R. Lacy. 2025-06-16. Marsh sediment in translation: A review of sediment transport across a natural tidal salt marsh in northern San Francisco Bay. https://doi.org/10.15447/sfews.2025v23iss2art6

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