title: Characterising organic matter in recirculating aquaculture systems with fluorescence EEM spectroscopy.
abstract: The potential of recirculating aquaculture systems (RAS) in the aquaculture industry is increasingly being acknowledged. Along with intensified application, the need to better characterise and understand the accumulated dissolved organic matter (DOM) within these systems increases. Mature RASs, stocked with rainbow trout and operated at steady state at four feed loadings, were analysed by dissolved organic carbon (DOC) analysis and fluorescence excitation-emission matrix (EEM) spectroscopy. The fluorescence dataset was then decomposed by PARAFAC analysis using the drEEM toolbox. This revealed that the fluorescence character of the RAS water could be represented by five components, of which four have previously been identified in fresh water, coastal marine water, wetlands and drinking water. The fluorescence components as well as the DOC showed positive correlations with feed loading, however there was considerable variation between the five fluorescence components with respect to the degree of accumulation with feed loading. The five components were found to originate from three sources: the feed; the influent tap water (groundwater); and processes related to the fish and the water treatment system. This paper details the first application of fluorescence EEM spectroscopy to assess DOM in RAS, and highlights the potential applications of this technique within future RAS management strategies.
authors.affiliation: National Institute for Aquatic Resources, Technical University of Denmark, Kavalergården 6, DK-2920 Charlottenlund, Denmark. Electronic address: adaha@aqua.dtu.dk.
authors.forename: A C
authors.initials: AC
authors.lastname: Hambly
authors.affiliation: Technical University of Denmark, Department of Environmental Engineering, DTU Environment, Miljoevej, Building 113, DK-2800 Kgs. Lyngby, Denmark.
authors.forename: E
authors.initials: E
authors.lastname: Arvin
authors.affiliation: Technical University of Denmark, DTU Aqua, Section for Aquaculture, The North Sea Research Centre, P.O. Box 101, DK-9850 Hirtshals, Denmark.
authors.forename: L-F
authors.initials: LF
authors.lastname: Pedersen
authors.affiliation: Technical University of Denmark, DTU Aqua, Section for Aquaculture, The North Sea Research Centre, P.O. Box 101, DK-9850 Hirtshals, Denmark.
authors.forename: P B
authors.initials: PB
authors.lastname: Pedersen
authors.affiliation: Technical University of Denmark, Department of Environmental Engineering, DTU Environment, Miljoevej, Building 113, DK-2800 Kgs. Lyngby, Denmark.
authors.forename: B
authors.initials: B
authors.lastname: Seredyńska-Sobecka
authors.affiliation: National Institute for Aquatic Resources, Technical University of Denmark, Kavalergården 6, DK-2920 Charlottenlund, Denmark.
authors.forename: C A
authors.initials: CA
authors.lastname: Stedmon
mesh_terms: D017756:Aquaculture; D004784:Environmental Monitoring / Q000379:methods*; D005163:Factor Analysis, Statistical; D006812:Humic Substances / Q000032:analysis*; D013050:Spectrometry, Fluorescence; D014874:Water Pollutants, Chemical / Q000032:analysis*; D018508:Water Purification
chemical_list: D006812:Humic Substances; D014874:Water Pollutants, Chemical
keywords: Dissolved organic matter (DOM); Fluorescence excitation-emission matrix (EEM) spectroscopy; PARAFAC analysis; Recirculating aquaculture systems (RAS)