Use of stable isotopes to investigate dispersal of waste from fish farms as a function of hydrodynamics

Abstract

Stable isotopes were used to examine differential effects of fish farm waste on the water column and sediments. To achieve this objective, we chose 3 marine fish farms located along the coast of Sicily (Mediterranean Sea) as point-source disturbances, and a control area. The hypothesis that carbon and nitrogen isotope composition of particulate (POM) and sedimentary (SOM) organic matter varied with increasing distance (from cages to 1000 m) was tested at 3 levels of hydrodynamics: low (mean velocity of current [MVC] ~12 cm s

Exchange of nutrients and oxygen across the sediment–water interface below a Sparus aurata marine fish farm in the north-western Mediterranean Sea

“…This indicates that there is a high amount of dilution in the zone as a consequence of the high hydrodynamic behaviour of open seawater, making it impossible to detect differences in the phytoplankton biomass. This corroborates the observations made for similar fish farms in the Mediterranean by Pitta et al (1999) and Sarà et al (2006).…”

Integrated Multitrophic Aquaculture: Filter Feeders Bivalves as Efficient Reducers of Wastes Derived from Coastal Aquaculture Assessed with Stable Isotope Analyses

“…Another explanation could be a larger filtering capacity and high waste assimilation by filter feeders therefore less organic matter will be available for incorporation at SOM. Other studies (Sarà et al, 2004(Sarà et al, , 2006 have addressed effects of farming wastes to POM and SOM, but no inclusion of all organic sources and consumers have been considered. Our study improves knowledge on fish farms effects by integrating filter feeders bivalves.…”

“…The effects of the organic enrichment are widely studied in the Atlantic and the Pacific Ocean, especially in relation to the salmon industry (Brown et al, 1987;Cheshuk et al, 2003;Weston, 1991), however, knowledge of fish farming impacts in the Mediterranean Sea is scarce (Sarà et al, 2004(Sarà et al, , 2006Vizzini & Mazzola, 2004), which have different hydrographic characteristics, such as shallow waters and low current velocity areas, and are characterized by oligotrophic waters.…”

Hydrodynamic effects on the origin and quality of organic matter for bivalves: an integrated isotopic, biochemical and transplant study

“…Hydrodynamic processes remove, distribute, canalise and transfer the available organic matter pool through the biota (Emerson 1990, Sarà et al 2006, redistributing it for biological consumption (Lenihan et al 1996, Wildish & Kristmanson 1997. In shallow aquatic habitats, organic matter fluxes are driven by hydrodynamic processes that determine the magnitude of food supply to consumers, depending on its origin and quality.…”