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Fishery and Sea Resources100%Decembera100%Aprilb90%90%80%80%70%70%60%60%50%50%40%Impact 1 Impact 2 Control 1 Control 2Nematoda Oligochaeta Polychaeta Copepoda KinorhynchaNemertini Gastrotricha Turbellaria Ostracoda others100%90%80%70%60%50%40%JulyImpact 1 Impact 2 Control 1 Control 2Nematoda Oligochaeta Polychaeta Copepoda KinorhynchaNemertini Gastrotricha Turbellaria Ostracoda othersc40%Impact 1 Impact 2 Control 1 Control 2Nematoda Oligochaeta Polychaeta Copepoda KinorhynchaNemertini Gastrotricha Turbellaria Ostracoda others100%90%80%70%60%50%40%OctoberImpact 1 Impact 2 Control 1 Control 2Nematoda Oligochaeta Polychaeta Copepoda KinorhynchaNemertini Gastrotricha Turbellaria Ostracoda othersdFigure 2: Meiofaunal community structures in the four sampling periods: (a) December,(b) April, (c) July and (d) October.all of the other remaining taxa was lowerthan 1%.In the control stations, the meiofaunal communitystructure was dominated by nematodes(accounting for 51.4 to 86.8% of totalmeiofaunal abundance at Control 2 station,in July and October, respectively), followedby copepods (range: 4.0 to 25.4%),polychaetes (range 0.6 to 9.4%, at Impact 2station, in October and July, respectively),gastrotrichs (range: 1.3 to 7.4%, in Decemberand April, respectively), kynorhinchs(range: 1.7 to 2.1%, in April and December,respectively) and oligochaetes (range:0.2 to 2.5%, at Impact 1 station, in Decemberand October, respectively). The contributionof all of the other remaining taxawas lower than 1%.4 DiscussionThe potential spatial impact of fish-farm industriesFish farms generally release largeamounts of soluble and particulate organicmatter (POM) into the surroundings [18]and may thereby exert bottom-up pressureon the benthic community [19]. We foundconsiderably higher organic matter concentrationsunder the cages compared tocontrol sites, during the entire study.Downward fluxes derived from fishfarmingactivities contribute to the accumulationof organic matter in fish-farmsediments and have the potential to changethe distribution patterns of benthic assemblages[20, 21].Fish farm sediments have been observed2168