Publication Date:
2022-05-25
Description:
Author Posting. © The Author(s), 2016. This is the author's version of the work. It is posted here by permission of Coastal and Estuarine Research Federation for personal use, not for redistribution. The definitive version was published in Estuaries and Coasts 39 (2016): 1746–1761, doi: 10.1007/s12237-016-0106-0.
Description:
Increased interest in using bivalve cultivation to mitigate eutrophication requires a
comprehensive understanding of the net carbon (C) and nitrogen (N) budgets associated with
cultivation on an ecosystem scale. This study quantified C and N processes related to clam
(Mercenaria mercenaria) aquaculture in a shallow coastal environment (Cherrystone Inlet, VA)
where the industry has rapidly increased. Clam physiological rates were compared with basin-wide ecosystem fluxes including primary production, benthic nutrient regeneration, and
respiration. Although clam beds occupy only 3% of the ecosystem’s surface area, clams filtered
7-44% of the system’s volume daily, consumed an annual average of 103% of the phytoplankton
production, creating a large flux of particulate C and N to the sediments. Annually, N
regenerated and C respired by clam and microbial metabolism in clam beds were ~3-fold and
~1.5-fold higher, respectively, than N and C removed through harvest. Due to the short water
residence time, the low watershed load, and the close vicinity of clam beds to the mouth of
Cherrystone Inlet, cultivated clams are likely subsidized by phytoplankton from the Chesapeake
Bay. Consequently, much of the N released by mineralization associated with clam cultivation is
‘new’ N as it would not be present in the system without bivalve facilitation. Macroalgae that are
fueled by the enhanced N regeneration from clams represents a eutrophying process resulting
from aquaculture. This synthesis demonstrates the importance of considering impacts of bivalve
aquaculture in an ecosystem context especially relative to the potential of bivalves to remove
nutrients and enhance C sinks.
Description:
This work was supported by Virginia Sea Grant (NA10OAR4170085, #R/71515W, #R/715168), the NSF GK12 Fellowship (DGE-0840804), the Strategic Environmental Research and
Development Program – Defense Coastal/Estuarine Research Program Project SI-1413, and NSF
Virginia Coast Reserve LTER Project (DEB 0080381, DEB 0621014).
Description:
2017-05-19
Keywords:
Clam
;
Aquaculture
;
Nitrogen
;
Carbon
;
Bivalve
;
Ecosystem budget
Repository Name:
Woods Hole Open Access Server
Type:
Preprint
Permalink
