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"Pilado add Value": valorisation of non-traditional marine resources

Avelelas, Francisco Pires
Fonte: Instituto Politécnico de Leiria Publicador: Instituto Politécnico de Leiria
Tipo: Dissertação de Mestrado
Publicado em //2013 POR
Relevância na Pesquisa
48.36%
Dissertação para obtenção do Grau de Mestre em Biotecnologia dos Recursos Marinhos apresentada à ESTM - Escola Superior de Turismo e Tecnologia do Mar do Instituto Politécnico de Leiria.; In recent years, the valorisation of by-products resulted from fisheries discards has received much attention due to the awareness of economic and environmental negative impacts. However, the crustacean shellfish by-products contain several compounds that can be processed to yield chitin which has a myriad of industrial and biotechnological applications. The swimming crab, Polybius henslowii, despite being an extremely abundant marine resource, it is not presently subject to commercial use. Given the negative impact on the fishing nets fisherman´s see this marine resource as a plague and not as a potential source of economic incomes. Thereby, this work aims to be a contribution for the economic valorisation of Polybius henslowii as a raw material for polymer extraction, aiming for biotechnological purposes. Chitin and chitosan were extracted and produced from segmented body parts of Polybius henslowii: pereopods and carapace. Chitosan served then as raw material for the production of water-soluble chitosans (WSC) and chitooligosaccharides (COS)...

Notes on some rare and little known marine invertebrates from the Azores, with a discussion of the zoogeography of the region

Wirtz, Peter; Martins, Helen R.
Fonte: Universidade dos Açores Publicador: Universidade dos Açores
Tipo: Artigo de Revista Científica
Publicado em //1993 ENG
Relevância na Pesquisa
27.6%
Descreve-se brevemente a ocorrência das seguintes espécies de invertebrados marinhos das águas açoreanas: os moluscos Pleurobranchus testudinarius, Aplysia fasciata, Diaphorodoris luteocincta, Discodoris atromaculata, Platydoris argo, Polycera elegans, Tambja ceutae, os crustáceos Lysmata nilita, Eualus occultus, Aristaeomorpha foliacea, Aristeus antennatus, Cycloes cristata, Pilumnus hirtellus, Polybius henslowii, o foronídeo Phoronis cf. hippocrepia, o equinoderme Brissus unicolor, sendo todos novos registos para a Região. Fizeram-se também algumas observações sobre: o bivalve Pteria hirundo, os crustáceos Plesiopenaeus edwardsianus, Liocarcinus marmoreus, Plagusia depressa, Inachus phalangium, Albunea carabus, o equinoderme Centrostephanus longispinis e o tunicado Clavelina lepadiformis. Os 16 novos registos confirmam o conceito bem estabelecido de a fauna e flora litoral dos Açores terem "características Mediterrâneas".; ABSTRACT: We briefly comment on the occurrence of the following marine invertebrate species in Azorean waters: the molluscs Pleurobranchus testudinarius, Aplysia fasciata, Diaphorodoris luteocincta, Discodoris atromaculata, Platydoris argo, Polycera elegans, Tambja ceutae, the crustaceans Lysmata nilita...

SURVIVAL ESTIMATES OF BYCATCH INDIVIDUALS DISCARDED FROM BIVALVE DREDGES

Leitão,Francisco; Range,Pedro; Gaspar,Miguel Baptista
Fonte: Universidade de São Paulo, Instituto Oceanográfico Publicador: Universidade de São Paulo, Instituto Oceanográfico
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2014 EN
Relevância na Pesquisa
27.45%
The fate of released bycatch is an issue of great interest for fisheries research and management. Survival experiments were carried out to assess the survival capacity of animals damaged and discarded during clam dredging operations. Three common bycatch species, two fish (Trachinus vipera; Dicologlossa cuneata) and one crab (Polybius henslowii), were collected during the sorting of catches from a commercial dredging boat. An arbitrary score scale was used to quantify the type and extent of damage to the organisms. Onboard, damaged individuals were placed in tanks containing seawater which were subsequently transferred to the laboratory. Survival experiments were conducted during the subsequent 48h. D. cuneata exhibited the lowest mortality after 48h (54%), followed by P. henslowii (65%) and T. vipera (81%). Despite the magnitude of the percentage mortalities determined, the average number of individuals estimated to die during a 15 minutes tow (standard commercial fishing time) was relatively small: 1.2, 3.24 and 11 for D. cuneata, T. vipera and P. henslowii, respectively. Nevertheless, when these figures are extrapolated to cover all the dredging fleet the impact of this practice on the populations of the species studied can be significant...

Warm-water decapods and the trophic amplification of climate in the North Sea

Lindley, J. A.; Beaugrand, G.; Luczak, C.; Dewarumez, J.-M.; Kirby, R. R.
Fonte: The Royal Society Publicador: The Royal Society
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
26.89%
A long-term time series of plankton and benthic records in the North Sea indicates an increase in decapods and a decline in their prey species that include bivalves and flatfish recruits. Here, we show that in the southern North Sea the proportion of decapods to bivalves doubled following a temperature-driven, abrupt ecosystem shift during the 1980s. Analysis of decapod larvae in the plankton reveals a greater presence and spatial extent of warm-water species where the increase in decapods is greatest. These changes paralleled the arrival of new species such as the warm-water swimming crab Polybius henslowii now found in the southern North Sea. We suggest that climate-induced changes among North Sea decapods have played an important role in the trophic amplification of a climate signal and in the development of the new North Sea dynamic regime.

Megabenthic decapod crustacean assemblages on the Galician continental shelf and upper slope (north-west Spain)

Fariña Pérez, Antonio Celso; Freire, Juan (1966-); González Gurriarán, Eduardo
Fonte: Springer-Verlag Publicador: Springer-Verlag
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
27.97%
The structure of megabenthic decapod crustacean assemblages on the Galician (north-west Spain) continental shelf (100 to 200 depth) and upper slope (200 to 500 m) was analyzed based on surveys carried out in autumn and spring, from 1980 to 1987. Forty species belonging to 19 families were caught. The portunid crab "Polybius henslowii", a species with pelagic phases, was the most abundant species, but displayed strong spatial and temporal fluctuations. Other dominant species were the Norway lobster "Nephrops norvegicus", the portunid "Liocarcinus depurator", the galatheids "Munida intermedia" and "M. sarsi", and the shrimps "Solenocera membranacea", "Plesionika heterocarpus", "Pasiphaea sivado" and "Dichelopandalus bonnieri". Total abundance and biomass (average values excluding Polybius henslowii = 255 individuals and 2.06 kg/30 min tow) and species richness and diversity, Ht (6.85 species and Ht = 1.45 per tow) displayed a significant positive correlation with depth, and strong interannual fluctuations. The factors determining community organization were depth and, to a lesser extent, spatial structure. There was clear evidence of bathymetric zonation, differentiating between species characteristic of the slope ("D. bonnieri" and "Pasiphaea sivado")...

Trophic ecology of the swimming crab Polybius henslowii Leach, 1820 in Galician and Cantabrian Seas: Influences of natural variability and the Prestige oil spill

Signa, G.; Cartes, Joan Enric; Solé, Montserrat; Serrano, Alberto; Sánchez, Francisco
Fonte: Elsevier Publicador: Elsevier
Tipo: Artículo Formato: 22195 bytes; application/pdf
ENG
Relevância na Pesquisa
47.91%
9 pages, 9 figures, 2 tables.-- Printed version published Nov 15, 2008.; Diet and feeding intensity of the portunid crab Polybius henslowii were studied during the spring of 2004 along Galician and Cantabrian continental shelves (NW Iberian Peninsula) between 78 and 287 m. The area had been affected by the Prestige oil spill in November 2002, with different sectors at different levels of pollution: highest in between Miño River and Cape Finisterre (MF) and from there to Estaca de Bares Point (FE) and lowest from Estaca to Cape Peñas (EP). From 37272 specimens collected in 59 bottom hauls, 342 were analysed for stomach fullness and diet composition. Stomach fullness was lower in FE, but with no significant differences among sectors. Diet was a mixture of pelagic and benthic prey: cephalopods (Ilex coindetti), brachyurans (P. henslowii) and polychaetes (Glycera sp.). Other prey were beloniform eggs and fish remains. Two stress markers were also studied in some specimens: Acetylcholinesterase (a neurotoxicity marker) varied among sampled areas, while lipid peroxidation (an oxidative stress marker) did not. Changes in trophic variables, distribution and density were analysed in relation to depth, surface and bottom T, surface Chl a from satellite imagery and tar aggregate concentration in sediments. Along Galician and Cantabrian coasts prey availability...

SURVIVAL ESTIMATES OF BYCATCH INDIVIDUALS DISCARDED FROM BIVALVE DREDGES

Leitão, Francisco; Range, Pedro; Gaspar, Miguel Baptista
Fonte: Universidade de São Paulo. Instituto Oceanográfico Publicador: Universidade de São Paulo. Instituto Oceanográfico
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; Formato: application/pdf
Publicado em 01/12/2014 ENG
Relevância na Pesquisa
27.71%
The fate of released bycatch is an issue of great interest for fisheries research and management. Survival experiments were carried out to assess the survival capacity of animals damaged and discarded during clam dredging operations. Three common bycatch species, two fish (Trachinus vipera; Dicologlossa cuneata) and one crab (Polybius henslowii), were collected during the sorting of catches from a commercial dredging boat. An arbitrary score scale was used to quantify the type and extent of damage to the organisms. Onboard, damaged individuals were placed in tanks containing seawater which were subsequently transferred to the laboratory. Survival experiments were conducted during the subsequent 48h. D. cuneata exhibited the lowest mortality after 48h (54%), followed by P. henslowii (65%) and T. vipera (81%). Despite the magnitude of the percentage mortalities determined, the average number of individuals estimated to die during a 15 minutes tow (standard commercial fishing time) was relatively small: 1.2, 3.24 and 11 for D. cuneata, T. vipera and P. henslowii, respectively. Nevertheless, when these figures are extrapolated to cover all the dredging fleet the impact of this practice on the populations of the species studied can be significant...