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Title: Coastal marine megaripple fields are metabolic hotspots with highly dynamic oxygen exchange
Abstract Megaripples are current‐generated seafloor bedforms of well‐sorted sand or gravel and wavelengths over 1 m. In this aquatic eddy covariance study, we measured large rates of benthic primary production and respiration for a shallow‐water sandy megaripple field exposed to strong tidally driven currents and intense sunlight. Current and light were the main short‐term drivers of a highly dynamic oxygen exchange. Daytime oxygen release as high as 300 mmol m−2 d−1and nighttime oxygen uptake up to −100 mmol m−2 d−1were likely sustained by current‐driven transport of oxygen, nutrients, and organic matter (fuel) into and out of the sand and superimposed by rapid internal cycling. Seasonal differences in temperature (45%) and light (69%) between April and September were the main long‐term drivers of substantially greater rates of gross primary production and respiration in September. The megaripples functioned as an intense metabolic hotspot with carbon cycling rates larger than those of most near‐shore sediments.  more » « less
Award ID(s):
1851290 1851424
PAR ID:
10495818
Author(s) / Creator(s):
;
Publisher / Repository:
Wiley Periodicals LLC
Date Published:
Journal Name:
Limnology and Oceanography Letters
Volume:
8
Issue:
6
ISSN:
2378-2242
Page Range / eLocation ID:
867 to 875
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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