143 research outputs found
PRESENCIA DE MILLERIGOBIUS MACROCEPHALIJS (KOLOMBATOVIC, 1891) (TELEOSTEI: GOBIIDAE) EN EL MEDITERRÁNEO OCCIDENTAL, CON NOTAS SOBRE SU BIOLOGIA
M. Macrocephalus has been viously indicated in the Adriatic Sea (Jugoslavia) and the Mediterranean Eastern basin (Rhodes lsland and Israel) on infratlittoral rocky bottoms.
A relative high number of individuals of this specie has been sampled in the Mar Menor (SE coast, lberian Peninsula), a hyperhaline coastal lagoon, on the Cymodocea Caulerpa beds. The size range and the sexual maturity degree, suggest a stable population of the specie in this lagoon. This allows us to expand the limited knowledge on the biology, ecology and geographical distribution of this gobiid.M. macrocephalus ha sido señalado con anterioridad en el Adriático (Yugoslavia) y en el Mediterráneo oriental (isla de Rodas e Israel), sobre fondos rocosos infralitorsles.
Un número relativamente elevado de ejemplares de dicha especie ha sido muestreado en el Mar Menor (costa SE. península ibérica), una laguna costera hipersalina, sobre pradera de Cimodocea-caulerpa. La variedad de tallas y grado de madurez sexual sugieren una población estable en dicha laguna. Ello permite ampliar el limitado conocimiento sobre la biología, ecología y distribución geográfica que actualmente se posee de este góbido
Are Taxonomic Distinctness measures compliant to other ecological indicators in assessing ecological status?
Assessing the ecological status, a concept implemented in the European Water Framework Directive [EC, 2000. Directive of the European Parliament and of the Council 2000/60/EC establishing a framework for community action in the field of water policy PE-CONS 3639/1/00, p. 72], requires the application of methods capable of distinguishing different levels of ecological quality. The Average Taxonomic Distinctness has been used as tool in this context, and we tested the robustness of Taxonomic Distinctness measures applying it in different scenarios (estuarine eutrophication, organic pollution, and re-colonisation after physical disturbance), analysing simultaneously its compliance to other types of ecological indicators. Results show that, in most of the case studies, only Total Taxonomic Distinctness was relatively satisfactory in discriminating between disturbed situations. Other Taxonomic Distinctness measures have not proved to be more sensitive than other ecological indicators (Shannon-Wiener, Margalef, and Eco-Exergy indices). Therefore, this approach does not seem to be particularly helpful in assessing systems' ecological status with regard to the WFD implementation.http://www.sciencedirect.com/science/article/B6V6N-4KHK1M9-3/1/e54484859b25163a57c5780ac3bf46c
Bathymetry time series using high spatial resolution satellite images
The use of the new generation of remote sensors, such as echo sounders and Global Navigation Satellite System (GNSS) receivers with di erential correction installed in a drone, allows the acquisition of high-precision data in areas of shallow water, as in the case of the channel of the Encañizadas in the Mar Menor lagoon. This high precision information is the first step to develop the methodology to monitor the bathymetry of the Mar Menor channels. The use of high spatial resolution satellite images is the solution for monitoring many hydrological changes and it is the basis of the three-dimensional (3D) numerical models used to study transport over time, environmental variability, and water ecosystem complexity
Density dependence in marine protected populations: a review
The cessation or reduction of fishing in marine protected areas (MPAs) should promote an increase in abundance and mean size and age of previously exploited populations. Thus density-dependent changes in life-history characteristics should occur when populations are allowed to recover in MPAs. In this review, we synthesize the existing information on resource limitation in marine ecosystems, density-dependent changes in life-history traits of exploited populations and evidence for biomass export from MPAs. Most evidence for compensatory changes in biological variables has been derived from observations on populations depleted by high fishing mortality or on strong year classes, but these changes are more evident in juveniles than in adults and in freshwater rather than in marine systems. It is unclear if adults of exploited marine populations are resource limited. This may suggest that exploited populations are controlled mainly by density-independent processes, which could be a consequence of the depleted state of most exploited populations. MPAs could be a useful tool for testing these hypotheses. If we assume that resources become limiting inside MPAs, it is plausible that, if suitable habitats exist, mobile species will search for resources outside of the MPAs, leading to export of biomass to areas which are fished. However, it is not possible to establish from the available data whether this export will be a response to resource limitation inside the MPAs, the result of random movements across MPA boundaries or both. We discuss the implications of this process for the use of MPAs as fisheries management tools.Financial support was provided by the EU CEC DGXII – MAST III contract number: MAS3-ct97-0155
Microstructure and secondary phases in coevaporated CuInS2 films: Dependence on growth temperature and chemical composition
The microstructure of CuInS2-(CIS2) polycrystalline films deposited onto Mo-coated glass has been analyzed by Raman scattering, Auger electron spectroscopy (AES), transmission electron microscopy, and x-ray diffraction techniques. Samples were obtained by a coevaporation procedure that allows different Cu-to-In composition ratios (from Cu-rich to Cu-poor films). Films were grown at different temperatures between 370 and 520-°C. The combination of micro-Raman and AES techniques onto Ar+-sputtered samples has allowed us to identify the main secondary phases from Cu-poor films such as CuIn5S8 (at the central region of the layer) and MoS2 (at the CIS2/Mo interface). For Cu-rich films, secondary phases are CuS at the surface of as-grown layers and MoS2 at the CIS2/Mo interface. The lower intensity of the MoS2 modes from the Raman spectra measured at these samples suggests excess Cu to inhibit MoS2 interface formation. Decreasing the temperature of deposition to 420-°C leads to an inhibition in observing these secondary phases. This inhibition is also accompanied by a significant broadening and blueshift of the main A1 Raman mode from CIS2, as well as by an increase in the contribution of an additional mode at about 305 cm-1. The experimental data suggest that these effects are related to a decrease in structural quality of the CIS2 films obtained under low-temperature deposition conditions, which are likely connected to the inhibition in the measured spectra of secondary-phase vibrational modes
Assessment of biomass export from marine protected areas and its impacts on fisheries in the Western Mediterranean Sea
Occurrence of priority pollutants in WWTP effluents and Mediterranean coastal waters of Spain
A comprehensive study aimed at evaluating the occurrence, significance of concentrations and spatial distribution of priority pollutants (PPs) along the Comunidad Valenciana coastal waters (Spain) was carried out in order to fulfil the European Water Framework Directive (WFD). Additionally, PP concentrations were also analysed in the effluent of 28 WWTPs distributed along the studied area. In coastal waters 36 organic pollutants of the 71 analysed, including 26 PPs were detected although many of them with low frequency of occurrence. Only 13 compounds, which belong to four different classes (VOCs, organochlorinated pesticides, phthalates and tributyltin compounds (TBT)) showed a frequency of occurrence above 20% in coastal waters. In the results obtained until now, octylphenol, pentachlorobenzene, DEHP and TBT exceeded the annual average concentration (EQS-AAC), and only TBT surpassed the maximum allowable concentration (EQS-MAC). The most frequent contaminants determined in coastal waters were also present in WWTP effluents. (C) 2011 Elsevier Ltd. All rights reserved.Financial support from Conselleria de Medio Ambiente, Agua, Urbanismo y Vivienda de la Generalitat Valenciana (Application of Water Framework Directive 2000/60/EC on endocrine disruptors and priority substances in coastal areas in the Comunidad Valenciana) is gratefully acknowledged.Martí Ortega, N.; Aguado García, D.; Segovia Martínez, L.; Bouzas Blanco, A.; Seco Torrecillas, A. (2011). Occurrence of priority pollutants in WWTP effluents and Mediterranean coastal waters of Spain. Marine Pollution Bulletin. 62(3):615-625. doi:10.1016/j.marpolbul.2011.01.010S61562562
First records, rediscovery and compilation of deep-sea echinoderms in the middle and lower continental slope of the Mediterranean Sea
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