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1.
Sensors (Basel) ; 20(9)2020 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-32384795

RESUMO

Since 2014, the global land and sea surface temperature has scaled 0.23 °C above the decadal average (2009-2018). Reports indicate that Mediterranean Sea temperatures have been rising at faster rates than in the global ocean. Oceanographic time series of physical and biogeochemical data collected from an onboard and a multisensor mooring array in the northwestern Mediterranean Sea (Blanes submarine canyon, Balearic Sea) during 2009-2018 revealed an abrupt temperature rising since 2014, in line with regional and global warming. Since 2014, the oligotrophic conditions of the water column have intensified, with temperature increasing 0.61 °C on the surface and 0.47 °C in the whole water column in continental shelf waters. Water transparency has increased due to a decrease in turbidity anomaly of -0.1 FTU. Since 2013, inshore chlorophyll a concentration remained below the average (-0.15 mg·l-1) and silicates showed a declining trend. The mixed layer depth showed deepening in winter and remained steady in summer. The net surface heat fluxes did not show any trend linked to the local warming, probably due to the influence of incoming offshore waters produced by the interaction between the Northern Current and the submarine canyon. Present regional and global water heating pattern is increasing the stress of highly diverse coastal ecosystems at unprecedented levels, as reported by the literature. The strengthening of the oligotrophic conditions in the study area may also apply as a cautionary warning to similar coastal ecosystems around the world following the global warming trend.

2.
PLoS One ; 13(8): e0202995, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30157276

RESUMO

There are many marine protected areas (MPAs) containing coral reef aggregations in the eastern Pacific region. However, the connectivity of corals between MPAs is still poorly known, especially in the Marine Conservation Corridor of the Eastern Tropical Pacific (MCCETP). Here, we assess the potential connectivity of corals across equatorial eastern Pacific MPAs through a Lagrangian particle-tracking algorithm coupled offline with an ocean-circulation numerical model. Connectivity metrics and graph theory were used to analyze the networks and highlight those MPAs that are critical for maintaining the connectivity of corals across the region. Our results show that the equatorial eastern Pacific MPAs form a relatively well-connected network, at least 40% of coral larvae released per year end up within the boundaries of an MPA. MPAs like Malpelo and Gorgona islands included in the MCCETP were found to be critical for connectivity of corals because of their high betweenness centrality and potential role as stepping-stones between coastal MPAs and offshore MPAs such as the Galapagos Islands. Two pelagic larval duration (PLD) scenarios (40 and 130 days) indicate a quasi-unidirectional larval flow from coastal MPAs toward oceanic MPAs, where the only resilient MPAs (Coiba and Malpelo islands) depend mostly on subsidiary recruitment from MPAs located along the coast of Costa Rica, Panama and Colombia. In the two PLD scenarios, Cocos Island maintains a very low resilience potential. Our results indicate the imperative need to include coastal MPAs in the MCCETP network initiative, since connectivity and resilience of coral reefs in the equatorial eastern Pacific region rely heavily on coastal MPAs.


Assuntos
Antozoários/fisiologia , Fenômenos Biofísicos , Conservação dos Recursos Naturais , Modelos Estatísticos , Distribuição Animal , Animais , Hidrodinâmica , Larva/fisiologia , Oceano Pacífico
3.
Sensors (Basel) ; 11(12): 11251-72, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22247664

RESUMO

The new pelagic Operational Observatory of the Catalan Sea (OOCS) for the coordinated multisensor measurement of atmospheric and oceanographic conditions has been recently installed (2009) in the Catalan Sea (41°39'N, 2°54'E; Western Mediterranean) and continuously operated (with minor maintenance gaps) until today. This multiparametric platform is moored at 192 m depth, 9.3 km off Blanes harbour (Girona, Spain). It is composed of a buoy holding atmospheric sensors and a set of oceanographic sensors measuring the water conditions over the upper 100 m depth. The station is located close to the head of the Blanes submarine canyon where an important multispecies pelagic and demersal fishery gives the station ecological and economic relevance. The OOCS provides important records on atmospheric and oceanographic conditions, the latter through the measurement of hydrological and biogeochemical parameters, at depths with a time resolution never attained before for this area of the Mediterranean. Twenty four moored sensors and probes operating in a coordinated fashion provide important data on Essential Ocean Variables (EOVs; UNESCO) such as temperature, salinity, pressure, dissolved oxygen, chlorophyll fluorescence, and turbidity. In comparison with other pelagic observatories presently operating in other world areas, OOCS also measures photosynthetic available radiation (PAR) from above the sea surface and at different depths in the upper 50 m. Data are recorded each 30 min and transmitted in real-time to a ground station via GPRS. This time series is published and automatically updated at the frequency of data collection on the official OOCS website (http://www.ceab.csic.es/~oceans). Under development are embedded automated routines for the in situ data treatment and assimilation into numerical models, in order to provide a reliable local marine processing forecast. In this work, our goal is to detail the OOCS multisensor architecture in relation to the coordinated capability for the remote, continuous and prolonged monitoring of atmospheric and oceanographic conditions, including data communication and storage. Accordingly, time series of measurements for a number of biological parameters will be presented for the summer months of 2011. Marine hindcast outputs from the numerical models implemented for simulating the conditions over the study area are shown. The strong changes of atmospheric conditions recorded in the last years over the area have altered the marine conditions of living organisms, but the dimension of the impact remains unclear. The OOCS multisensor coordinated monitoring has been specifically designed to address this issue, thus contributing to better understand the present environmental fluctuations and to provide a sound basis for a more accurate marine forecast system.


Assuntos
Atmosfera , Oceanografia , Espanha
4.
Rev. biol. trop ; 55(3/4): 839-852, Sep.-Dec. 2007. ilus, graf
Artigo em Espanhol | LILACS | ID: lil-637631

RESUMO

Reproductive cycle of the mollusk Atrina maura (Pterioidea: Pinnidae) in a coastal lagoon system of the Mexican South Pacific. From February 1997 to February 1998, random samples of the mollusk Atrina maura were collected on a monthly basis from the Corralero-Alotengo lagoon system, Oaxaca, Mexico. The soft parts were separated from the valve, washed in situ, and placed in a Davison solution. The gonadosomatic index (GSI) and the muscle yield index (MYI) were measured, and the reproductive cycle was characterized by histological cuts. A. maura has two important reproductive periods, one from April to July and another from October to November; there is a resting period from August to September. The reproductive cycle has a direct relationship with the GSI and a reverse relationship with the MYI. There was evidence of a close relationship of the spawning and post-spawning periods with the water temperature (R = 0.991, p = 0.002). Females dominate numerically throughout the year, but the difference is significant (X²: p= 0.05) only in November. Rev. Biol. Trop. 55 (3-4): 839-852. Epub 2007 December, 28.


De febrero de 1997 a febrero de 1998, se recolectaron mensualmente muestras aleatorias del molusco Atrina maura en el sistema lagunar Corralero-Alotengo, Oaxaca, México. Se extrajeron las partes blandas para lavarlas in situ y fijarlas en solución Davison. En el laboratorio se pesaron para obtener los índices gonadosomático (IGS) y de rendimiento muscular (IRM), y mediante cortes histológico de las gónadas se caracterizó el ciclo reproductivo. Esta población se reproduce casi todo el año, con dos periodos reproductivos importantes: uno de abril a julio y otro de octubre a noviembre, y una sola época de reposo, en agosto y septiembre. El ciclo reproductivo tiene una relación directa con el IGS e inversa con el IRM. Hay evidencias de una relación estrecha de las época de desove y postdesove con la temperatura del agua (R = 0.991, p 0.002). Las hembras predominaron casi todo el año, aunque esta proporción solo tuvo diferencias estadísticamente significativas en noviembre (X²: p= 0.05).


Assuntos
Animais , Feminino , Masculino , Bivalves/fisiologia , Gônadas/crescimento & desenvolvimento , Maturidade Sexual/fisiologia , México , Reprodução/fisiologia , Estações do Ano
5.
Rev Biol Trop ; 55(3-4): 839-52, 2007.
Artigo em Espanhol | MEDLINE | ID: mdl-19086389

RESUMO

From February 1997 to February 1998, random samples of the mollusk Atrina maura were collected on a monthly basis from the Corralero-Alotengo lagoon system, Oaxaca, Mexico. The soft parts were separated from the valve, washed in situ, and placed in a Davison solution. The gonadosomatic index (GSI) and the muscle yield index (MYI) were measured, and the reproductive cycle was characterized by histological cuts. A. maura has two important reproductive periods, one from April to July and another from October to November; there is a resting period from August to September. The reproductive cycle has a direct relationship with the GSI and a reverse relationship with the MYI. There was evidence of a close relationship of the spawning and post-spawning periods with the water temperature (R = 0.991, p > 0.002). Females dominate numerically throughout the year, but the difference is significant (chi2: p > or = 0.05) only in November.


Assuntos
Bivalves/fisiologia , Gônadas/crescimento & desenvolvimento , Maturidade Sexual/fisiologia , Animais , Feminino , Masculino , México , Reprodução/fisiologia , Estações do Ano
6.
Rev. biol. trop ; 50(3/4): 1091-1100, sept.-dic. 2002. ilus, tab, graf
Artigo em Espanhol | LILACS | ID: lil-350091

RESUMO

The abundance, population structure, and growth of the Pen-shell Atrina maura in the Corralero-Alotengo tropical lagoon system in Oaxaca, Mexico, were studied from February to September of 1997. An abundance analysis showed significant temporal and spatial differences (Kruskal-Wallis, p < 0.001). Two spatial groups of abundance were found in the area, one from the mouth of the lagoon system to the middle of the Pen-shell bank, and the other between the middle of the Pen-shell bank and the head of the system. Three temporal periods of abundance were found (February-April-May; July-August; March-June-September). The distribution of population size showed that benthic recruitment of A. maura occurred from February to July. Length frequency of A. maura is commonly wide-ranging; nevertheless, in this study Pen-shell organisms with a valve length of 15 cm were frequently found. The growth rate length was 3.7 cm/month during the dry season (February to May), and 3.5 cm/month during the rainy season (June to September). Sex ratio was maintained at 1:1 from February to May, but males were dominant from June to August, and the minimum length for reproduction was registered at 10 cm valve length


Assuntos
Animais , Masculino , Feminino , Moluscos , Água Doce , Moluscos , Densidade Demográfica , Estações do Ano , Maturidade Sexual
7.
Rev Biol Trop ; 50(3-4): 1091-100, 2002.
Artigo em Espanhol | MEDLINE | ID: mdl-12947592

RESUMO

The abundance, population structure, and growth of the Pen-shell Atrina maura in the Corralero-Alotengo tropical lagoon system in Oaxaca, Mexico, were studied from February to September of 1997. An abundance analysis showed significant temporal and spatial differences (Kruskal-Wallis, p < 0.001). Two spatial groups of abundance were found in the area, one from the mouth of the lagoon system to the middle of the Pen-shell bank, and the other between the middle of the Pen-shell bank and the head of the system. Three temporal periods of abundance were found (February-April-May; July-August; March-June-September). The distribution of population size showed that benthic recruitment of A. maura occurred from February to July. Length frequency of A. maura is commonly wide-ranging; nevertheless, in this study Pen-shell organisms with a valve length of 15 cm were frequently found. The growth rate length was 3.7 cm/month during the dry season (February to May), and 3.5 cm/month during the rainy season (June to September). Sex ratio was maintained at 1:1 from February to May, but males were dominant from June to August, and the minimum length for reproduction was registered at 10 cm valve length.


Assuntos
Bivalves/fisiologia , Animais , Bivalves/crescimento & desenvolvimento , Feminino , Água Doce , Masculino , México , Densidade Demográfica , Estações do Ano , Maturidade Sexual
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