960 resultados para North East China Transect
Resumo:
A geophysical survey was conducted off Vancouver and Queen Charlotte Islands over a four-week period (July 12 to August 5, 1970) as part of HUDSON-70 expedition. The HUDSON-70 expedition was organized as part of the Canadian contribution to the International Decade of Oceanographic Exploration. The geophysical survey was conducted to study the subsurface structure across the continental margin off the British Columbia coast and in the deep ocean basins. The present report contains descriptions of the various measurements made during this cruise and the data collected.
Resumo:
The Early Miocene Napak XV locality (ca 20.5 Ma), Uganda, has yielded an interesting assemblage of fossils, including the very well represented amphicyonid Hecubides euryodon. The remarkable find of a nearly complete mandible, unfortunately with poorly preserved dentition, together with new dental remains allow us to obtain a better idea about the morphology and variability of this species. Additionally, we describe a newly discovered mandible of Hecubides euryodon from the Grillental-VI locality (Sperrgebiet, Namibia), which is the most complete and diagnostic Amphicyonidae material found in this area. Comparisons with Cynelos lemanensis from Saint Gérand le Pouy (France), the type locality, and with an updated sample of the species of amphicyonids described in Africa leads us to validate the genus Hecubides. Hecubides would be phylogenetically related to the medium and large size species of Amphicyonidae from Africa, most of them now grouped into the genera Afrocyon and Myacyon, both endemic to this continent.
Resumo:
In the context of demands by the European feminist movement at the beginning of the 20th century, in Spain women’s sport flagged up aspirations to what were considered to be male practices. The first experiences of women in football stand out because of their use of the media to appear as a symbol of social transformation to modernity in the 20th century. It was not in vain that women’s football highlighted the demands of the feminist movements, although it did come up against male disapproval from an opposing group. The research sets out from a bibliographical and media review of specialist press and sports news of the time. Other current studies have also been considered in order to place it in a social and historical focus on sport. This has enabled us to highlight that football in Spain was established as an unequivocal space for (re) producing male hegemony where women were relegated to the representation of a symbolic ritual in a scenario of accessory and condescension.
Resumo:
The ocean sunfish (Mola mola) is the world’s heaviest bony fish reaching a body mass of up to 2.3 tonnes. However, the prey M. mola consumes to fuel this prodigious growth remains poorly known. Sunfish were thought to be obligate gelatinous plankton feeders, but recent studies suggest a more generalist diet. In this study, through molecular barcoding and for the first time, the diet of sunfish in the north-east Atlantic Ocean was characterised. Overall, DNA from the diet content of 57 individuals was successfully amplified, identifying 41 different prey items. Sunfish fed mainly on crustaceans and teleosts, with cnidarians comprising only 16% of the consumed prey. Although no adult fishes were sampled, we found evidence for an ontogenetic shift in the diet, with smaller individuals feeding mainly on small crustaceans and teleost fish, whereas the diet of larger fish included more cnidarian species. Our results confirm that smaller sunfish feed predominantly on benthic and on coastal pelagic species, whereas larger fish depend on pelagic prey. Therefore, sunfish is a generalist predator with a greater diversity of links in coastal food webs than previously realised. Its removal as fisheries’ bycatch may have wider reaching ecological consequences, potentially disrupting coastal trophic interactions.
Resumo:
The ocean sunfish (Mola mola) is the world’s heaviest bony fish reaching a body mass of up to 2.3 tonnes. However, the prey M. mola consumes to fuel this prodigious growth remains poorly known. Sunfish were thought to be obligate gelatinous plankton feeders, but recent studies suggest a more generalist diet. In this study, through molecular barcoding and for the first time, the diet of sunfish in the north-east Atlantic Ocean was characterised. Overall, DNA from the diet content of 57 individuals was successfully amplified, identifying 41 different prey items. Sunfish fed mainly on crustaceans and teleosts, with cnidarians comprising only 16% of the consumed prey. Although no adult fishes were sampled, we found evidence for an ontogenetic shift in the diet, with smaller individuals feeding mainly on small crustaceans and teleost fish, whereas the diet of larger fish included more cnidarian species. Our results confirm that smaller sunfish feed predominantly on benthic and on coastal pelagic species, whereas larger fish depend on pelagic prey. Therefore, sunfish is a generalist predator with a greater diversity of links in coastal food webs than previously realised. Its removal as fisheries’ bycatch may have wider reaching ecological consequences, potentially disrupting coastal trophic interactions.
Resumo:
Cuttlefish are currently the highest yielding cephalopod group harvested in the north-east Atlantic. English Channel cuttlefish show seasonal migrations to and from deep offshore wintering grounds, which results in a large number of smaller cuttlefish within the offshore stocks, some of which are caught by trawlers. Discarding small cuttlefish from trawls may give them the opportunity to migrate inshore and spawn, but only if they survive. This study examined survival rates of small (<15-cm dorsal mantle length) cuttlefish caught on board a commercial beam trawler. Overall, 31% of the small cuttlefish caught remained alive by the time they reached the sorting table (immediate survival rate). This survival rate dropped to 16% after specimens were subsequently held in an on-board aquarium system for up to 72 h (short-term survival rate). Measures that reduce the capture of small cuttlefish in the first place and/or increase their survival could potentially benefit the stocks.
Resumo:
Cuttlefish are currently the highest yielding cephalopod group harvested in the north-east Atlantic. English Channel cuttlefish show seasonal migrations to and from deep offshore wintering grounds, which results in a large number of smaller cuttlefish within the offshore stocks, some of which are caught by trawlers. Discarding small cuttlefish from trawls may give them the opportunity to migrate inshore and spawn, but only if they survive. This study examined survival rates of small (<15-cm dorsal mantle length) cuttlefish caught on board a commercial beam trawler. Overall, 31% of the small cuttlefish caught remained alive by the time they reached the sorting table (immediate survival rate). This survival rate dropped to 16% after specimens were subsequently held in an on-board aquarium system for up to 72 h (short-term survival rate). Measures that reduce the capture of small cuttlefish in the first place and/or increase their survival could potentially benefit the stocks.
Resumo:
Growing evidence has shown a profound modification of plankton communities of the North East Atlantic and adjacent seas over the past decades. This drastic change has been attributed to a modification of the environmental conditions that regulate the dynamics and the spatial distribution of ectothermic species in the ocean. Recently, several studies have highlighted modifications of the regional climate station L4 (50° 15.00′N, 4° 13.02′W) in the Western English Channel. We here focus on the modification of the plankton community by studying the long-term, annual and seasonal changes of five zooplankton groups and eight copepod genera. We detail the main composition and the phenology of the plankton communities during four climatic periods identified at the L4 station: 1988–1994, 1995–2000, 2001–2007 and 2008–2012. Our results show that long-term environmental changes underlined by Molinero et al. (2013) drive a profound restructuration of the plankton community modifying the phenology and the dominance of key planktonic groups including fish larvae. Consequently, the slow but deep modifications detected in the plankton community highlight a climate driven ecosystem shift in the Western English Channel.
Resumo:
Growing evidence has shown a profound modification of plankton communities of the North East Atlantic and adjacent seas over the past decades. This drastic change has been attributed to a modification of the environmental conditions that regulate the dynamics and the spatial distribution of ectothermic species in the ocean. Recently, several studies have highlighted modifications of the regional climate station L4 (50° 15.00′N, 4° 13.02′W) in the Western English Channel. We here focus on the modification of the plankton community by studying the long-term, annual and seasonal changes of five zooplankton groups and eight copepod genera. We detail the main composition and the phenology of the plankton communities during four climatic periods identified at the L4 station: 1988–1994, 1995–2000, 2001–2007 and 2008–2012. Our results show that long-term environmental changes underlined by Molinero et al. (2013) drive a profound restructuration of the plankton community modifying the phenology and the dominance of key planktonic groups including fish larvae. Consequently, the slow but deep modifications detected in the plankton community highlight a climate driven ecosystem shift in the Western English Channel.