Biogeography of the deep-sea galatheid squat lobsters of the Pacific Ocean     

Enrique Macpherson  Bertrand Richer de Forges  Kareen Schnabel  Sarah Samadi  Marie-Catherine Boisselier  Antoni Garcia-Rubies 《Deep Sea Research Part I: Oceanographic Research Papers》2010,57(2):228-238

We analyzed the distribution patterns of the galatheid squat lobsters (Crustacea, Decapoda, Galatheidae) of the Pacific Ocean. We used the presence/absence data of 402 species along the continental slope and continental rise (200–2000 m) obtained from 54 cruises carried out in areas around the Philippines, Indonesia, Solomon, Vanuatu, New Caledonia, Fiji, Tonga, Wallis and Futuna and French Polynesia. The total number of stations was ca. 3200. We also used published data from other expeditions carried out in the Pacific waters, and from an exhaustive search of ca. 600 papers on the taxonomy and biogeography of Pacific species. We studied the existence of biogeographic provinces using multivariate analyses, and present data on latitudinal and longitudinal patterns of species richness, rate of endemism and the relationship between body sizes with the size of the geographic ranges. Latitudinal species richness along the Western and Eastern Pacific exhibited an increase from higher latitudes towards the Equator. Longitudinal species richness decreased considerably from the Western to the Central Pacific. Size frequency distribution for body size was strongly shifted toward small sizes and endemic species were significantly smaller than non-endemics. This study concludes that a clear separation exists between the moderately poor galatheid fauna of the Eastern Pacific and the rich Western and Central Pacific faunas. Our results also show that the highest numbers of squat lobsters are found in the Coral Sea (Solomon-Vanuatu-New Caledonia islands) and Indo-Malay-Philippines archipelago (IMPA). The distribution of endemism along the Pacific Ocean indicates that there are several major centres of diversity, e.g. Coral Sea, IMPA, New Zealand and French Polynesia. The high proportion of endemism in these areas suggests that they have evolved independently.  相似文献   

Climatic bisection of the last interglacial warm period in the Polar North Atlantic     

Henning A. Bauch  Evguenia S. Kandiano  Jan Helmke  Nils Andersen  Antoni Rosell-Mele  Helmut Erlenkeuser 《Quaternary Science Reviews》2011,30(15-16):1813-1818

New multiproxy marine data of the Eemian interglacial (MIS5e) from the Norwegian Sea manifest a cold event with near-glacial surface ocean summer temperatures (3–4 °C). This mid-Eemian cooling divided the otherwise relatively warm interglacial climate and was associated with widespread expansions of winter sea-ice and polar water masses due to changes in atmospheric circulation and ocean stability. While the data also verify a late rather than early last interglacial warm peak, which is in general disharmony with northern hemisphere insolation maximum and the regional climatic progression of the early Holocene, the cold event itself was likely instrumental for delaying the last interglacial climate development in the Polar North when compared with regions farther south. Such a ‘climatic decoupling’ of the Polar region may bear profound implications for the employment of Eemian conditions to help evaluate the present and future state of the Arctic cryosphere during a warming interglacial.  相似文献   

Episodic Biogeochemical Variability in a Low-Flow Mediterranean Estuary     

Gotzon Basterretxea  Antoni Jordi  Marly Carolina Martínez-Soto  Antonio Tovar-Sánchez 《Estuaries and Coasts》2017,40(5):1247-1262

To investigate to what extent episodic physical processes regulate nutrient availability and phytoplankton assemblages of the Mahon estuary (Minorca Island), we carried out an intensive field study during 2010–2011. During the study period, environmental conditions spanned from intense stratification to a continuous mixing and from lack of riverine inflow to intense runoff. Our data reveals a sequence of biogeochemical states of the estuary that result from the interplay between runoff, other non-periodic forcings (winds, sea level oscillations), and variations in water renewal. Seasonal runoff was revealed as a major driver of winter circulation and of the influx of inorganic nutrients, in particular nitrate. However, because of the combination between runoff and flushing time, the effects of floodwater events on phytoplankton are short-lived (days). Conversely, during summer, when freshwater influx declines, water renewal relies on pulsed atmospheric forcing that may be of local or remote origin. As depicted from the low nitrate concentrations (<1 μM) and enhanced ammonium (>1 μM), this change in circulation and external loads carries nutrient assimilation within the estuary head and forces the use of remnant nutrients through regenerating pathways to sustain an enhanced phytoplankton biomass at the lower estuary. Episodic variability represented between 52 and 65% of the annual chlorophyll variance. Despite the fact that episodic pulses represented intense departures from base biogeochemical state of the estuary, at time scale larger than weeks, the phytoplankton community composition and dynamics was largely regulated by the integrated effect of these episodes and other environmental drivers associated with seasonality rather than by individual storm events only. Our results suggest that even though the system presents good recovery capacity to individual storm episodes, it may be more vulnerable to increased nutrient fluxes during summer, as well as to changes in episode timing and frequency.  相似文献   

Life history of the bathyal octopus Pteroctopus tetracirrhus (Mollusca,Cephalopoda) in the Mediterranean Sea     

Antoni Quetglas  Francesc Ordines  María González  Ignacio Franco 《Deep Sea Research Part I: Oceanographic Research Papers》2009,56(8):1379-1390

The life cycle of the deep-sea octopus Pteroctopus tetracirrhus was studied from monthly samples obtained throughout the year in different areas of the western Mediterranean (mainly around the Balearic Islands and along the coast of the Iberian Peninsula). A total of 373 individuals (205 females, 168 males) were analyzed; females ranged from 4.5 to 14.0 cm mantle length (ML) and males from 4.5 to 11.5 cm ML. There were few small-sized octopuses (<7 cm ML) in the samples, which might indicate that these individuals inhabit rocky grounds that are not accessible to trawlers or waters deeper than the maximum depth sampled (800 m). The species occurred more frequently around the Balearic Islands than along the Iberian Peninsula as they appeared in 20% and 7%, respectively, of the hauls in these areas. The octopus inhabits the lower continental shelf and upper slope in both areas, primarily between 200 and 500 m depth. Modal lengths were followed from autumn, when recruits were caught by trawlers, to summer, when reproduction took place. Females grew from 8 to 10 cm ML from winter to spring, but this modal size did not increase further in summer; males grew from 7 to 9 cm ML from winter to spring. The total disappearance of large individuals after summer suggests a life cycle lasting a single year. The evolution of the monthly mean sizes showed that the growth was best described by log-linear functions in both sexes. The length at first maturity was clearly higher in females (12 cm ML) than in males (8 cm ML). A total of 30 different prey items, belonging to four major taxonomic groups (crustaceans, osteichthyes, cephalopods and gastropods), were identified in the stomach contents. The diet of the octopus was based on crustaceans and teleosts, which accounted for 75% and 23% of the prey items, respectively. Cephalopods and gastropods were accessory prey as they only represented 1.6% and 0.7%, respectively, of the total. The octopus showed a marked preference for the benthic fish Symphurus nigrescens and the endobenthic crustacean Alpheus glaber. The bathymetric distribution of P. tetracirrhus coincides with those of these two main prey, which suggests that the distribution of the octopus might be strongly linked to its trophic resources.  相似文献   

Parametric rolling behaviour of azimuthing propulsion-driven ships     

Osman Turan  Zafer Ayaz  Seref Aksu  Jan Kanar  Antoni Bednarek 《Ocean Engineering》2008,35(13):1339-1356

The study investigates the experimental and numerical analysis of the occurrence of auto-parametric rolling for large, high-speed pod-driven ships in waves. Considering unique design and performance targets, the aim here is to exploit susceptibility to auto-parametric rolling behaviour and to identify probable design and operational precautions. In order to achieve this aim, an existing non-linear time-domain software to simulate capsizing and other critical manoeuvring behaviours of slow- to medium-speed conventional and podded ships in waves is being enhanced for fast pod-driven vessels and then compared against the dedicated model test conducted in long-crested regular and random waves for a large, pod-driven containership model. This paper includes the presentation of current numerical modifications for pod-driven ships and the verification analysis.  相似文献   

Regional dynamics of socio-economic change —The experiences and prospects in sparsely populated areas     

Antoni Kukliński Prof. Dr. 《GeoJournal》1986,12(1):107-110

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The Holocene Evolution of the Ebre Delta Catalonia, Spain   总被引：2，自引：0，他引：2  

Antoni Canicio  Carles Iban～ez 《地理学报》1999,54(5)

１　ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｅｆｉｒｓｔｒｅｌｅｖａｎｔｉｎｆｏｒｍａｔｉｏｎａｂｏｕｔｔｈｅｇｅｏｌｏｇｙａｎｄｅｖｏｌｕｔｉｏｎａｒｙｔｒｅｎｄｓｏｆｔｈｅＥｂｒｅｄｅｌｔａｃａｍｅａｓｐａｒｔｏｆａｓｔｒａｔｉｇｒａｐｈｉｃｓｔｕｄｙｂｙＭａｌｄｏｎａｄｏＡ［１］．Ｈｅｍｅｎｔｉｏｎｅｄｔｈａｔｄｕｒｉｎｇｔｈｅｌａｓｔｔｒａｎｓｇｒｅｓｓｉｖｅｅｖｅｎｔ,ｔｈａｔｉｓｂｅｆｏｒｅｓｅａｌｅｖｅｌｒｅａｃｈｅｄｉｔｓｐｒｅｓｅｎｔｌｅｖｅｌ,ｄｅｌｔａｉｃｐｒｏｇｒａｄａｔｉｏｎｏｎｌ…  相似文献   

The recreational fishery off Majorca Island (western Mediterranean): some implications for coastal resource management   总被引：3，自引：0，他引：3  

Morales-Nin  Beatriz; Moranta  Joan; Garcia  Cristina; Tugores  Maria Pilar; Grau  Antoni Maria; Riera  Francisco; Cerda  Margalida 《ICES Journal of Marine Science》2005,62(4):727-739

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Book reviews     

Roy  B. K.  Stanley  William R.  Bronger  Dirk  Dlin  Norman  Kukliński  Antoni  Cori  Berardo  Babikir  A. A. A.  Kunkel  G.  César  N.  Martin  Kähler 《GeoJournal》1989,18(2):255-260

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Regional stratigraphy and distribution of epigenetic stratabound celestine, fluorite, barite and Pb–Zn deposits in the MVT province of northeastern Mexico     

Francisco González-Sánchez  Antoni Camprubí  Eduardo González-Partida  Rafael Puente-Solís  Carles Canet  Elena Centeno-García  Viorel Atudorei 《Mineralium Deposita》2009,44(3):343-361

Northeastern Mexico hosts numerous epigenetic stratabound carbonate-hosted low-temperature hydrothermal deposits of celestine, fluorite, barite and zinc-lead, which formed by replacement of Mesozoic evaporites or carbonate rocks. Such deposits can be permissively catalogued as Mississippi Valley-type (MVT) deposits. The deposits studied in the state of Coahuila are associated with granitic and metasedimentary basement highs (horsts) marginal or central to the Mesozoic Sabinas Basin. These horsts controlled the stratigraphy of the Mesozoic basins and subsequently influenced the Laramide structural pattern. The Sabinas Basin consists of ~6,000-m-thick Jurassic to Cretaceous siliciclastic, carbonate and evaporitic series. The MVT deposits are mostly in Barremian and in Aptian-Albian to Cenomanian formations and likely formed from basinal brines that were mobilized during the Laramide orogeny, although earlier diagenetic replacement of evaporite layers (barite and celestine deposits) and lining of paleokarstic cavities in reef carbonates (Zn–Pb deposits) is observed. Fluid inclusion microthermometry and isotopic studies suggest ore formation due to mixing of basinal brines and meteoric water. Homogenization temperatures of fluid inclusions range from 45°C to 210°C; salinities range from 0 to 26 wt.% NaCl equiv., and some inclusions contain hydrocarbons or bitumen. Sulfur isotope data suggest that most of the sulfur in barite and celestine is derived from Barremian to Cenomanian evaporites. Regional geology and a compilation of metallogenic features define the new MVT province of northeastern Mexico, which comprises most of the state of Coahuila and portions of the neighboring states of Nuevo León, Durango and, perhaps extends into Zacatecas and southern Texas. This province exhibits a regional metal zonation, with celestine deposits to the south, fluorite deposits to the north and barite and Zn–Pb deposits mostly in the central part.  相似文献