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Ne/KyFishery and Sea ResourcesNematode/Kynorhinchs ratio200180160140120100806040200Dec Apr Jul OctImpact 1 Impact 2 Control 1 Control 2Figure 4: Temporal variations of Nematode/Kynorhinchs ratio at the Control and Impactedstations.4.1 Meiofaunal assemblagesMeiofauna are becoming good tool to reflectchanges of environmental disturbanceboth spatially and temporally [15, 25]. Thegeneral outcome is that anthropogenic disturbancealters meiofaunal abundance, diversity,biomass, and species composition.Meiofaunal abundance in this study wascomparable to values reported from otherfarm sediments, but we observed a strongreduction in density at the impacted stationswhen compared to the Control sites(for about 40%, Figure 1).In a similar study on fish-cage impact,Mirto et al. [26] pointed out a clear reductionof the meiofaunal abundance in systemssubjected to high organic load, andthe drastic reduction (50-70%) in meiofaunaabundances has been reported fromother fish farm areas in the Mediterranean[23, 13, 27, 28].Biodeposition influenced also the meiofaunalassemblages inhabiting farmsediments,in terms of organisms abundance,and each taxon showed a differentsensitivity to the presence of fish-farms(Figure 2).The sediment organic enrichment, determinedaltered conditions under the cages.This caused a modification of the meiobenthiccommunity structure in comparison tothe Control sites with increased significanceof copepods (from 11.3 to 23.4% ofthe total density), polychaetes (from 3.8 to10.5%), oligochaetes (from 1.2 to 3.7%),2170