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This content will become publicly available on May 4, 2024

Title: Recovery of salt marsh vegetation after ice-rafting
Sediment transport on salt marsh platforms is usually brought about through storm events and high tides. At high latitudes, ice-rafting is a secondary mechanism for sediment transport, redistributing sediment from tidal flats, channels, and ponds to marshland. In January 2018, winter storm Grayson hit the North Atlantic coast, producing a large storm surge and a significant decrease in temperature. The Great Marsh in Plum Island Sound, Massachusetts, USA, experienced an unprecedented sediment deposition due to ice-rafting, burying marsh vegetation. Plant vegetation recovery was investigated in 17 sediment patches, dominated by Spartina patens , Distichlis spicata, Juncus gerardi , and S. alterniflora . The analysis was carried out considering the number of stems and stem height for each vegetation species. D. spicata firstly occupied bare patches, while S. patens , once smothered by sediment, regrew slowly. The number of stems of S. patens inside the sediment patches recovered, on average, after 2 growing seasons. The number of J. gerardi stems was not significantly affected by ice-rafted sediment deposition. S. alterniflora dynamics were different depending on physical and edaphic conditions. At some locations, S. alterniflora did not recover after sediment deposition. The deposition of the sediment layer had a positive effect on vegetation vigor, increasing stem height and maintaining high stem density. The results suggest a beneficial effect of sediment deposition not only for marsh accretion, but also for marsh vegetation growth, both of which are fundamental for marsh restoration.  more » « less
Award ID(s):
2224608 1832221
NSF-PAR ID:
10423563
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Marine Ecology Progress Series
Volume:
710
ISSN:
0171-8630
Page Range / eLocation ID:
57 to 70
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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