1,720,969 research outputs found
Structure and functioning of the Northern Adriatic coastal ecosystem, within the context of the Marine Strategy Framework implementation
No full textThe Northern Adriatic Sea summarizes all different critical elements of a ‘typical’ coastal area, such: important trawling activity in the inshore area, presence of aquaculture activities (mussels farms), widely distributed along the coast, presence of small scale fisheries activities, seaside touristic pressures, extended seaport activities. Among these pressures the project aims to investigate acquaculture and small scale fisheries activities within three miles from the coast. This would provide a better understanding of major impact sources and an identification of the processes that need to be preserved/enhanced to maintain or also increase the resilience of the system. Within this context, the main objectives of the project are: (1) to assess the role played by mussel culture farms, both in terms of negative impacts and positive feedbacks; (2) to focalize the attention on one of the main key factors presently affecting, but also structuring, the ecosystem in the NAS coastal area, in order to better understand the majors drivers also in terms of opportunities to be managed; (3) to define long term management objectives, indentifying the self-sustaining processes to be maintained or restored, in order to increase the system resilience and stimulate an adaptive management. To achieve these objectives, five issues were considered: benthic fauna; biogeochemical cycles; potential role as fish aggregating area; emergy analysis; artisanal fishery. The results of the present study show how a mussel farm located in a transitional environment near coast is a man made structure characterised by a sustainable use, with no direct impacts on bottom, acting as a fishing aggregating area also for some commercial species. Assimilating to an “extensive” acquaculture system, mussel farm is a structure characterised by the predominance of renewable inputs that, probably due to environmental factors such as currents and winds, doesn’t interfere both with benthic community and biogeochemical cycles of the area. Moreover the normal aggregating effects due to the confluence of great quantities of available food is increased by the presence, at the bottom, of some hard substrates, able to attract fishes species beyond for feeding, also for reproductive purpose. Nowadays, in a spatial planning management contest, the creation of further mussel farms even if may be encouraged by these results, at regional scale, it is not a firm economical sustainable, due to the low mussel selling price. Moving from this, modernize the production system by coupling mussel cultivations also with other incoming sources, may represent the right choice to maintain this type of sustainable acquacolture. Manage recreational fishing inside mussel farm may be among the feasible solutions.
In the end, as underlined by the investigation on potential role as fish aggregating area, the farm, being off-limits to commercial fishing, may act one-sidedly also as a fish maker, for the nearby areas, where artisanal fishery is allowed. By the present, this activity is a sustainable practice, but, due to the species dependence and to the catch composition in terms of thermal affinity groups show a high potential vulnerability. Small modifications both in fleet structures and in environmental conditions could drive the situation towards unsustainability. An increase in available fishes biomass may act as buffer effect towards vulnerability causes, by supporting possible new fishermen, fronting the problem of small modification in fleet structures. Moreover some of the fish species enhanced by mussel farm are temperate or warm species. Given the dependence of local artisanal fishery from cold or temperate species, a shift of catches toward temperate and warm ones’, without affecting incomings, might, at least partially, release this type of activity from the variations of the thermal regime as forecast by IPCC
Vulnerabilità della piccola pesca costiera del nord Adriatico ai cambiamenti climatici
No full textWithin the context of global warming, the western coast of the northern Adriatic Sea can be regarded as an extremely vulnerable area. By analysing the composition of landings from small-scale fisheries in terms of thermal affinity groups, we highlighted the potential vulnerability of these activities, being catches mainly composed by cold and temperate affinity species
Pesca artigianale e gestione della fascia costiera: due tipologie di habitat a confronto
No full textMonitoraggio acustico passivo di Sciaena umbra in un allevamento di mitili del Nord Adriatico
No full textA passive listening survey was conducted in a mussel farm, characterised by the presence of concrete structures on the bottom. The area was located adjacent to the mouth of Sile river (1 nautical mile from the coast) in the Venetian littoral zone. The monitoring proved to be successful in detecting Sciaena umbra drumming sounds. The distribution of the species was assessed on acoustic basis, suggesting that the concrete artificial structures of the area may work as reproductive FAD for breeding aggregations of Sciaena umbra
Analisi comparativa di indicatori di diversità applicati alla comunità macrobentonica della Laguna di Venezia
No full textBiodiversità della Laguna di Venezia e della costa nord adriatica veneta. – Atherina hepsetus ( Linneus, 1758): seconda segnalazione per la Laguna di Venezia.
No full textBiodiversità della laguna di Venezia della costa nord Adriatica veneta: segnalazione n. 221 - Eriocheir sinensis (H. Milne Edwars, 1853): seconda segnalazione per la laguna di Venezia.
No full textPresent and future status of artisanal fisheries in the Adriatic Sea (western Mediterranean Sea)
Full text linkArtisanal fisheries represents an important source of employment and income for many Mediterranean coastal communities, as well as an important cultural and traditional identity factor at a regional level. However, despite its importance, it is generally under-studied, in both ecological and socio-economic terms, so hampering the chance of developing sustainable and integrated management measures. At present, on the West coast of the Adriatic Sea, within the three-mile area, artisanal fisheries and hydraulic dredging are the only approved commercial fishing activities. This study confirmed the importance of the artisanal fisheries in this area, representing a multitarget and multigear activity. Despite the 39 exploited species, however, we found high vulnerability both for species (76% of total catches depend upon only three species-cuttlefish, mantis shrimp, and sole) and thermal affinity groups (cold and temperate species contributed to the entire catches). Furthermore, our data showed that fishing effort and CPUE values were greater than those reported at the regional level, and also indicated that the discard rate was lower than in other Adriatic areas. Regarding ecological effects, the two trophodynamic indicators that we applied showed a sustainable situation, but scenarios of possible changes in environmental or fishing effort conditions highlighted the proximity of the stock to the unsustainability threshold. Our findings suggest the need for an adequate management strategy to cope with possible future changes in population boundaries and conditions
Using passive acoustics to assess habitat selection by the brown meagre Sciaena umbra in a northern Adriatic Sea mussel farm.
No full textPassive acoustic monitoring (PAM) of the brown meagre Sciaena umbra was conducted in a northern
Adriatic Sea mussel farm. The level of acoustic activity was found to be constantly high from June to
August before declining sharply in September and there was significantly higher acoustic activity in
the structured habitats within the mussel farm than in the bare sandy bottom outside the farm. Results
are discussed in the context of the use of this species as an indicator species of artificial rocky habitats
along the Mediterranean coastal environments
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