TITLE:
Tidal Marsh Plant Community Development within Four Restored Lowland Estuaries in the Western Peninsulas of Washington State, USA
AUTHORS:
Shannon M. Call, Jenise M. Bauman
KEYWORDS:
Estuary Restoration, Habitat Recovery, Culvert Removal, Bridge Replacement
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.12 No.10,
October
22,
2021
ABSTRACT: Vegetation and soil within estuarine ecosystems play
an integral role in ecological processes within pocket estuaries. However,
physical barriers, caused by culverts diminish hydrological inputs, sediment exchange,
and habitat connectivity. The restoration of estuaries by bridge replacement
reconnects the aquatic corridor, however,
the recovery of plant communities and soil substrate is not well
understood. This observational study monitored four estuary restoration sites
of variable ages (0 - 12 years) in Western Washington, USA. Plant community
composition, soil organic carbon, organic matter, and soil nutrients were
assessed. Percent soil carbon was different among the pre-restoration and
youngest (3-year) post-restoration site (P = 0.03), suggesting an initial decrease in carbon and organic matter during
restoration. Both N and P were deficient at the newest, lower restoration site,
presumably linked to the lack of organic matter required for adequate cation
exchange capacity and nutrient/plant exchange (P P = 0.02). Vegetation composition was
primarily native species with few invasive plants present. The results of this
study illustrate that tidal marsh plant communities are influenced by the
development of salinity and vertical gradients with older sites having an
increase in species diversity. Future surveys are ongoing to better understand how these sites recover organic
matter and tidal marsh communities to form adequate estuarine habitat
over time.