Search results for "organic enrichment"
showing 4 items of 4 documents
Sediment features, macrozoobenthic assemblages and trophic relationships (δ13C and δ15N analysis) following a dystrophic event with anoxia and sulphi…
2007
Macrozoobenthic assemblages and stable carbon (delta C-13) and nitrogen (delta N-15) isotope values of various primary producers (macroalgae and angiosperms) and consumers (macroinvertebrate filter/suspension feeders, deposit feeders, detritivores/omnivores and carnivores and fishes) were studied in the Santa Giusta lagoon (Sardinia, Italy) before (spring) and after (autumn) a dystrophic event which occurred in the summer of 2004. A few days after the dystrophy, the physico-chemical characteristics of sediments and macrozoobenthic assemblages were also investigated. In the latter occasion, high total organic carbon (3.9%) and organic matter (15.9%) contents of surface sediments went togethe…
Meiofauna as indicator for assessing the impact of fish farming at exposed marine site
2012
This study aimed to detect the impact of organic loads due to biodeposition from a fish farm in an exposed area of the Strait of Sicily, Mediterranean Sea. Sediment chemistry and meiofaunal assemblages were investigated on a seasonal basis at four stations: two from the impacted area and two control stations. The presence of the cages induced a significant accumulation of proteins, lipids and biopolymeric carbon, resulting in a reduction in meiofaunal density at the impacted stations. Changes in community structure were also evident, as meiofauna under the cages were characterized by increased importance of polychaetes and copepods in comparison with a much lower importance of gastrotrichs …
Growth of Mytilus galloprovincialis (mollusca, bivalvia) close to fish farms: a case of integrated multi-trophic aquaculture within the Tyrrhenian Sea
2009
A current practice of marine aquaculture is to integrate fish with low-trophic-level organisms (e.g. molluscs and/or algae) during farming to minimise effects of cultivation on the surrounding environment and to potentially increase economic income. This hypothesis has been tested in the present article experimentally, by co-cultivating fish and mussels (Mytilus galloprovincialis) in the field. Integrated multi-trophic aquaculture (IMTA) experiments were started in July 2004 by transplanting mussel seed at two depths (-3 and -9 m) within 1,000 m downstream to fish cages and at 1,000 m upstream from cages. Mussels were cultured in nylon net bags for 12 months and the growth recorded biometri…
The fouling community as an indicator of fish farming impact in Mediterranean
2007
Fouling species richness, abundance and composition and biomass were chosen as the descriptors of effect of fish farm organic enrichment. The study was carried out in September 2004 in the Gulf of Castellammare (South Tyrrhenian, Mediterranean). The fouling species were sampled from plastic buoys spaced throughout the study area both up- [UP] and down-stream [DOWN]. The results showed that fouling community responded to the chronic input of allochthonous organic matter experiencing local changes more or less significantly with regard to abundance, species composition and general community diversity. Upper fouling would work as a first filter naturally opposed by environment resistance assim…