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  • Small, Coastal Temperate Rainforest Watersheds Dominate Dissolved Organic Carbon Transport to the Northeast Pacific Ocean
Title: Small, Coastal Temperate Rainforest Watersheds Dominate Dissolved Organic Carbon Transport to the Northeast Pacific Ocean
Abstract The northeast Pacific Coastal Temperate Rainforest (NPCTR) extending from southeast Alaska to northern California is characterized by high precipitation and large stores of recently fixed biological carbon. We show that 3.5 Tg‐C yr−1as dissolved organic carbon (DOC) is exported from the NPCTR drainage basin to the coastal ocean. More than 56% of this riverine DOC flux originates from thousands of small (mean = 118 km2), coastal watersheds comprising 22% of the NPCTR drainage basin. The average DOC yield from NPCTR coastal watersheds (6.20 g‐C m−2 yr−1) exceeds that from Earth's tropical regions by roughly a factor of three. The highest yields occur in small, coastal watersheds in the central NPCTR due to the balance of moderate temperature, high precipitation, and high soil organic carbon stocks. These findings indicate DOC export from NPCTR watersheds may play an important role in regional‐scale heterotrophy within near‐shore marine ecosystems in the northeast Pacific.  more » « less
Award ID(s):
1757348
PAR ID:
10432566
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
DOI PREFIX: 10.1029
Date Published:
Journal Name:
Geophysical Research Letters
Volume:
50
Issue:
12
ISSN:
0094-8276
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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