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Title: Watershed sediment cannot offset sea level rise in most US tidal wetlands
Watershed sediment can increase elevation of tidal wetlands struggling against rising seas, but where and how much watershed sediment helps is unknown. By combining contiguous US datasets on sediment loads and tidal wetland areas for 4972 rivers and their estuaries, we calculated that river sediment accretion will be insufficient to match sea level rise in 72% of cases because most watersheds are too small (median 21 square kilometers) to generate adequate sediment. Nearly half the tidal wetlands would require 10 times more river sediment to match sea level, a magnitude not generally achievable by dam removal in some regions. The realization that watershed sediment has little effect on most tidal wetland elevations shifts research priorities toward biological processes and coastal sediment dynamics that most influence elevation change.  more » « less
Award ID(s):
2049073
PAR ID:
10503869
Author(s) / Creator(s):
; ;
Publisher / Repository:
Science
Date Published:
Journal Name:
Science
Volume:
382
Issue:
6675
ISSN:
0036-8075
Page Range / eLocation ID:
1191 to 1195
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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