Search results for "TACE"
showing 10 items of 739 documents
Growth and reproduction of the deep-water rose shrimp, Parapenaeus longirostris (Lucas, 1846) (Decapoda, Penaeidae), in the southern Tyrrhenian sea.
2014
From June 2006 to May 2007, monthly samples of Parapenaeus longirostris (Lucas, 1846) were collected on land from the landings of two different, although contiguous, fishing grounds exploited by the bottom trawl fisheries of the two fishing harbours of Terrasini and Porticello, located on the north-western coast of Sicily. Carapace length (CL) of the female and male deep-water rose shrimp in Terrasini ranged from 9 to 32 mm and 13 to 26 mm, respectively, whereas in Porticello the length ranged from 8 to 31 mm and 13 to 26 mm, respectively. The Von Bertalanffy Growth Function parameters for Terrasini females and males were CLoo = 38.5 mm, K = 0.65 year(-1) and CL infinity = 32.5 mm, K = 0.85…
Un network italiano di Anfipodologi
2018
Attività e potenzialità del Network Italiano di Anfipodologi
Effect of the presence of the shore crab, Carcinus maenas, on the burrowing behaviour and clearance rate of the common cockle, Cerastoderma edule
2011
Bivalves demonstrate various morphological and behavioural adaptations to reduce the risk of being attacked by predators. This paper examines how the presence of the crab Carcinus maenas (L.), a natural predator of the cockle Cerastoderma edule (L.), affects its burrowing depth and clearance or feeding rate. Cockles were placed in experimental tanks and treated with three levels of predatory disturbance: (1) unfed crab loose inside the tank, (2) unfed crab inside a cage suspended in the water column and (3) no crab present. Cockles’ burrowing depth was measured in two sediment types: mud and sand. Cockles burrowed more deeply in treatments with no crabs. Burrowing depth in sand was signific…
Cetacean presence and distribution in the central Mediterranean Sea and potential risks deriving from plastic pollution
2021
Abstract The Sardinian and Sicilian Channels are considered hotspots of biodiversity and key ecological passages between Mediterranean sub-basins, but with significant knowledge gaps about marine mammal presence and potential threats they face. Using data collected between 2013 and 2019 along fixed transects, inter and intra-annual cetacean index of abundance was assessed. Habitat suitability, seasonal hot spots, and risk exposure for plastic were performed using the Kernel analysis and the Biomod2 R-package. 661 sightings of 8 cetacean species were recorded, with bottlenose and striped dolphins as the most sighted species. The north-eastern pelagic sector, the coastal waters and areas near…
On the occurrence and distribution of Calanipeda aquaedulcis Kritschagin, 1873 (Copepoda, Calanoida, Pseudodiaptomidae) in Sicily, Italy, with some n…
2019
The only population of the pseudodiaptomid copepod Calanipeda aquaedulcis Kritschagin, 1873 to date reported to occur in Sicily disappeared at the beginning of the XXI century due to deep environmental changes which affected the single site (Lake Biviere di Gela) known for this species on the island. In that site C. aquaedulcis is now replaced by Copidodiaptomus numidicus (Gurney, 1909), a diaptomid copepod whose distribution has been greatly increasing since the second half of the last century. In the present note, the occurrence of C. aquaedulcis in 12 novel water bodies spread throughout Sicily is reported, and some environmental data on the sites where the species was collected are prov…
By-catch of cetaceans and other species of conservation concern during pair trawl fishing operations in the Adriatic Sea (Italy)
2010
By-catch is one of the main sources of anthropogenic mortality in marine species of conservation concern worldwide. Between 2006 and 2008, the Consorzio Nazionale Interuniversitario per le Scienze del Mare (CoNISMa) coordinated a monitoring programme of cetacean by-catch in Italian pelagic trawlers, funded in compliance with European Regulation 812/2004. Sixteen independent observers monitored a total of 3141 hauls. The observation coverage ranged between 0.9 and 6.3% of the regional fishing effort. Almost all by-catch events were recorded in the northern Adriatic Sea. By-catch rates of bottlenose dolphins (Tursiops truncatus) and loggerhead turtles (Caretta caretta) were 0.0006 and 0.0255 …
Aquaculture effects on some physical and chemical properties of the water column: A meta-analysis
2007
More than 30 peer-reviewed articles (1980–2005) were analysed using meta-analytical reviewing techniques, and about 340 study cases were used to test whether aquaculture facilities had any effects on physical and chemical variables. The analysis tested differences between experimental conditions vs. chosen-by-author controls. Across all study cases, cultivated organisms (fish, shrimps and bivalves) did not have any clear effects on the water temperature and salinity. Dissolved oxygen also was found to be unaffected by aquaculture practices. On the other hand, crowding led to significant pH variations, which was more accentuated in shrimp (d+ = 0.66;P 0.05).Water transparency and turbidity w…
Seagrass detritus as marine macroinvertebrates attractor
2022
Seagrasses colonise coastal areas worldwide. Despite their high primary production, a considerable proportion becomes detritus that can be used as food, physical habitat and occasional or permanent shelter by several benthic macroinvertebrates. In turn, macroinvertebrates can contribute to regulating seagrass decomposition, and represent an important trophic link between primary producers and higher consumers. Nonetheless, several factors could modify colonizer responses to this habitat. In this study, we tested if colonisation of the seagrass detritus of Zostera noltei Hornemann, 1832 was related to substrate availability rather than food and whether the colonising assemblages were similar…
Leaf-like Structure in the Photosynthetic, Succulent Stems of Cacti
1991
This research examined the hypothesis that as cacti evolve to the leafless condition, the stem epidermis and cortex become more leaflike and more compatible with a photosynthetic role. All cacti in the relict genus Pereskia have non-succulent stems and broad, thin leaves. All members of the derived subfamily Cactoideae are ‘leafless’, having an expanded cortex that is the plant's only photosynthetic tissue. In Pereskia, leaves have a high stomatal density (mean: 50.7 stomata mm−2 in the lower epidermis, 38.1 mm−2 in the upper epidermis), but stems have low stomatal densities (mean: 11.3 mm 2, three of the species have none). Stems of Cactoideae have a high stomatal density (mean: 31.1 mm−2,…
A century of research on micro-organisms from the inland waters of the largest mediterranean island
2022
The first studies on the micro-organisms inhabiting Sicilian inland waters date back to the middle of the XIX century. However, these were based on single samples and mainly addressed at compiling faunistic and floristic inventories. It was in the first decades of the XX century that the first methodical studies were performed, which focussed on assessing microbial diversity in saline and hypersaline inland waters. Studies on plankton dynamics in ponds and reservoirs of the island started at the beginning of the 1980s and, since the end of the 1990s, temporary waters have also been intensively sampled, especially as regards phytoplankton and micro-crustaceans. These intensified sampling eff…