Resilience of dynamic coastal benthic ecosystems in response to large-scale finfish farming

Autor: Skye H. Woodcock, Marianne Holmer, Vivian Husa, Thomas Bruun Valdemarsen, Raymond Bannister, Nigel Keeley
Jazyk: angličtina
Rok vydání: 2019
Předmět:
Zdroj: Aquaculture Environment Interactions, Vol 11, Pp 161-179 (2019)
Aquaculture Environment Interactions
Keeley, N, Valdemarsen, T B, Woodcock, S, Holmer, M, Husa, V & Bannister, R J 2019, ' Resilience of dynamic coastal benthic ecosystems in response to large-scale finfish farming ', Aquaculture Environment Interactions, vol. 11, pp. 161-179 . https://doi.org/10.3354/aei00301
ISSN: 1869-7534
Popis: Global expansion of salmon aquaculture is contingent upon finding new, large-capacity farming locations that are, increasingly, situated in dispersive environments with atypical ecological characteristics. The capacity of such sites to assimilate organic waste and the type and spatial extent of effects remain poorly understood. This study couples intensive spatial and temporal measurements of waste outputs with measurements of benthic ecological diversity and sediment biogeochemistry at a shallow dispersive site on the central west coast of Norway. Despite minimal visual changes to the seabed, pronounced biological effects were evident out to 600-1000 m away from the farm. Greatly enhanced faunal and microbial activity was tightly coupled with strong sediment respiratory responses in the form of oxygen uptake and ammonia efflux. The benthic response was highly dynamic, with rapid and prolific colonization by opportunistic fauna, followed by substantive recovery during the subsequent 7 mo fallowing period. The fate and pathways of farm waste through the environment was compartmentalized by converting measured parameters into equivalent carbon fluxes. During early production, approximately 30-40% of the waste was accounted for by the measured benthic processes, attributed to faunal respiratory activity and the physical properties including sediment type. Later in the production cycle, a sediment burial event was observed down-current from the farm. The remaining 60-70% of organic waste was assumed to be either assimilated in the water column, consumed by large, unquantified benthic fauna, or exported and dispersed. Shallow, dispersive sites therefore appear relatively resilient to acute near-field enrichment, but are also more likely to result in accumulative, far-field effects.
Databáze: OpenAIRE