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Marine Areas (marine + area)
Selected AbstractsPotential multidrug resistance gene POHL: An ecologically relevant indicator in marine spongesENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 1 2001Anatoli Krasko Abstract Sponges are sessile filter feeders found in all aquatic habitats from the tropics to the arctic. Against potential environmental hazards, they are provided with efficient defense systems, e.g., protecting chaperones and/or the P-170/multidrug resistance pump system. Here we report on a further multidrug resistance pathway that is related to the pad one homologue (POH1) mechanism recently identified in humans. It is suggested that proteolysis is involved in the inactivation of xenobiotics by the POH1 system. Two cDNAs were cloned, one from the demosponge Geodia cydoniumand a second from the hexactinellid sponge Aphrocallistes vastus. The cDNA from G. cydonium, termed GCPOHL, encodes a deduced polypeptide with a size of 34,591 Da and that from A. vastus, AVPOHL, a protein of a calculated Mr of 34,282. The two sponge cDNAs are highly similar to each other as well as to the known sequences from fungi (Schizosaccharomyces pombe and Saccharomyces cerevisiae) and other Metazoa (from Schistosoma mansoni to humans). Under controlled laboratory conditions, the expression of the potential multidrug resistance gene POHL is, in G. cydonium, strongly upregulated in response to the toxins staurosporin (20 ,M) or taxol (50 ,M); the first detectable transcripts appear after 1 d and reach a maximum after 3 to 5 d of incubation. The relevance of the expression pattern of the G. cydonium gene POHL for the assessment of pollution in the field was determined at differently polluted sites in the area around Rovinj (Croatia; Mediterranean Sea, Adriatic Sea). The load of the selected sites was assessed by measuring the potency of XAD-7 concentrates of water samples taken from those places to induce the level of benzo[a]pyrene monooxygenase (BaPMO) in fish and to impair the multidrug resistance (MDR)/P-170 extrusion pump in clams. These field experiments revealed that the levels of inducible BaPMO activity in fish and of the MDR potential by the water concentrates are highly correlated with the level of expression of the potential multidrug resistance gene POHL in G. cydonium. This report demonstrates that the detoxification POH pathway, here mediated by the G. cydonium GCPOHL gene, is an additional marker for the assessment of the environmental load in a given marine area. [source] Zoning Marine Protected Areas through Spatial Multiple-Criteria Analysis: the Case of the Asinara Island National Marine Reserve of ItalyCONSERVATION BIOLOGY, Issue 2 2002Ferdinando Villa Systematic, objective approaches to site selection and design can help reconcile conflicting interests, represent stakeholders' viewpoints fairly and evenly, and extend the scope of planning studies from single reserves to networks. We illustrate the use of spatial multiple-criteria analysis for determining the suitability of marine areas for different uses and levels of protection. This technique couples geographic information systems (GIS) for land assessment and evaluation with a formal statement of the design priorities as seen from the different viewpoints of all involved stakeholders. The planning process, while staying focused on the main purposes of conservation and feasibility, involves all the main interest groups in the definition of priorities so that conflicts and tensions are kept under control. We used multiple-criteria analysis to integrate objective data with the contrasting priorities of different stakeholders in the planning of a marine protected area. The results of the analysis can be used to define an optimal spatial arrangement of different protection levels. As a case study, we developed a zoning plan for one of the first marine protected areas in Italy, the Asinara Island National Marine Reserve. Resumen: Puesto que el papel de las áreas marinas protegidas está siendo mejor entendido y se está volviendo más sofisticado, la planeación para abordar eficientemente estas áreas se está volviendo más complicada para las personas que toman decisiones. Las metodologías sistemáticas y objetivas para la selección de sitios y el diseño de reservas pueden ayudar a reconciliar los conflictos de intereses, representar los puntos de vista de los usuarios de manera equitativa y balanceada y extender la dimensión de los estudios de planeación para reservas individuales o en redes. Ilustramos el uso de un análisis de criterios espaciales múltiples para determinar la viabilidad de áreas marinas para diferentes usos y niveles de protección. Esta técnica une sistemas de información geográfica (GIS) para estimación y evaluación de suelos con una declaración de prioridades de diseño tal y como es percibida por los diferentes usuarios involucrados. El proceso de planeación, al mismo tiempo que se enfoca en los propósitos principales de la conservación y en su viabilidad, involucra a los principales grupos interesados en la definición de prioridades de tal manera que los conflictos y tensiones pueden ser manejadas. Utilizamos el análisis de criterios espaciales múltiples para integrar datos objetivos con las prioridades contrastantes de los diferentes usuarios en la planeación de un área marina protegida. Los resultados del análisis pueden ser usados como una guía para definir arreglos espaciales óptimos con diferentes niveles de protección. Como caso de estudio desarrollamos un plan de desarrollo de zonificación para una de las áreas marinas protegidas de Italia, la Reserva Nacional Marina de la Isla Asinara. [source] Reproduction of Micropogonias funieri in a shallow temperate coastal lagoon in the southern AtlanticJOURNAL OF FISH BIOLOGY, Issue 2002D. Vizziano The white croaker Micropogonias furnieri, in the coastal Rocha Lagoon, spawned during 5 months, in late spring and summer. It was eurythermic (gonad growth at 12·5 to 25·5° C, spawning at 20 to 27° C) and mesoxic (living at 5·2 to 9·1 mg l -1). The spawning occurred in brackish (8,18 salinity), basic (c. 8 pH) and oxygenated (c. 8·0 mg l -1) waters. The temperature appeared to be an important environmental factor affecting the timing of reproduction. The size at first maturity (19,20 cm) was 11,12 cm lower than the reported for the Río de la Plata spawning area (Uruguay). Juveniles were observed throughout most of the year suggesting that the lagoon is also a nursery area. In Brazil, M. furnieri spawns in marine areas while in Uruguay it spawns in estuaries. This is the first time that a coastal lagoon of the subtropical and temperate western coast of the South Atlantic Ocean has been shown to be a spawning area of a marine species. [source] Monitoring a Marine Coastal Area: Use of Mytilus galloprovincialis and Mullus barbatus as BioindicatorsMARINE ECOLOGY, Issue 2002Ilaria Corsi Abstract. Samples of Mytilus galloprovincialis and Mullus barbatus were collected in eight coastal sites along the South Adriatic and Ionic coasts of Italy in spring 2000 for a survey of coastal pollution in the Mediterranean basin. Specimens were analysed using an integrated approach based on residue analysis of common aquatic pollutants like organochlorines such as hexachlorobenzene (HCB), DDTs and polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), heavy metals and nonylphenols (NPnE) and biomarker responses such as acetylcholinesterase (AChE) activity, and the two specific P450 activities benzo(a)pyrene monooxygenase (BPMO) and 7-ethoxyre-sorufin-(9-deethylase (EROD). Biological and morphological parameters like somatic liver index (SLI), gonadosomatic index (GSI) and gonadal and gamete histology (eggs and sperms) were also evaluated in red mullet samples. A contamination gradient in which several hot spots occur were revealed in this study. The hot spots account for high levels of organochlorines in both species near incinerators and of PAHs in harbour areas. Levels of both NPnE and AChE activity were highest in two protected marine areas and were within detectable limits in others. This finding was confirmed by P450 activities, in which maximum levels were detected in harbours and protected marine areas. No morphological alterations of male and female gonads were observed on the histological level. [source] Reef shark declines in remote atolls highlight the need for multi-faceted conservation actionAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 5 2010Nicholas A. J. Graham Abstract 1.The decline of large-bodied predatory species in the oceans is a concern both from a sustainability perspective and because such species can have important ecological roles. Sharks are particularly vulnerable to fishing as their life histories are characterized by late age at maturity, large body size, and low fecundity. 2.Substantial shark population declines have been documented for a number of coastal and pelagic systems, with high population abundance limited to a few remote locations. The relative abundance and composition of reef shark populations are assessed from 1975 to 2006 at a remote, largely uninhabited, group of atolls in the central Indian Ocean; the Chagos Archipelago. 3.Number of sharks observed per scientific dive declined from a mean of 4.2 in the 1970s to 0.4 in 2006, representing a decline of over 90%. Silvertip sharks displayed an increase in abundance from 1996, whereas blacktip and whitetip reef sharks were rarely encountered in 2006. 4.Poaching in the archipelago, is the most likely cause of these declines, highlighted by a number of illegal vessels containing large numbers of sharks arrested since 1996. The data highlight that shark populations, even in remote, otherwise pristine, marine areas, are vulnerable to distant fishing fleets, and a range of strategies will need to be used in concert for their conservation. Copyright © 2010 John Wiley & Sons, Ltd. [source] Offshore spatial segregation in giant petrels Macronectes spp.: differences between species, sexes and seasonsAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue S1 2007J. González-Solís Abstract 1.Investigations were made to determine whether the two giant petrel species segregate by gender and species in relation to the stage of the annual cycle. The individual foraging behaviour of 14 male and 11 female northern giant petrels (Macronectes halli) and 13 male and 15 female southern giant petrels (M. giganteus) breeding at South Georgia were tracked over 1 year using geolocators (global location sensing loggers). 2.Males of both species showed a flexible foraging strategy, switching from coastal to pelagic habits, probably governed by spatio-temporal changes in carrion availability. In contrast, marine areas exploited by females were more consistent over the year and similar for the two species, with most foraging locations concentrated over the same pelagic waters. 3.This study provides support for the differences in foraging between sexes as the main mechanism reducing intraspecific competition. Although the two species are morphologically similar and can easily access each other's foraging habitat, they differ in the foraging areas exploited. Thus, interspecific competition seems mainly relaxed by spatial segregation, particularly between males in winter, probably mediated by different competitive abilities and physical tolerances to temperature and winds. Foraging southern giant petrels from South Georgia were not restricted to the areas within the line of equidistance to other colonies, but their foraging range overlapped with feeding grounds of conspecifics breeding in the Falkland Islands and the Antarctic Continent. 4.Taken together, these findings suggest that foraging selection on marine habitat heterogeneity reduces interspecific competition, whereas carrion availability reduces intersexual competition, in giant petrels. Copyright © 2008 John Wiley & Sons, Ltd. [source] Space,time patterns of co-variation of biodiversity and primary production in phytoplankton guilds of coastal marine environmentsAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 6 2003Maria Rosaria Vadrucci Abstract 1.The relevance of biodiversity to ecosystem processes is a major topic in ecology. Here, we analyse the relationship between biodiversity and productivity of the nano- and micro-phytoplankton guilds in coastal marine ecosystems. 2.The patterns of variation of species richness, diversity and primary productivity (as 14C assimilation) were studied in two marine areas: a eutrophic,mesotrophic area beside the River Po delta (northern Adriatic) and an oligotrophic area around the Salento peninsula (southern Adriatic,Ionian). The study was carried out at 23 sites in the northern area and at 45 sites in the southern area. Sites were arranged on expected spatial and temporal gradients of primary productivity variation, according to distance from the coast, optical depths and seasonal period. 3.167 taxa were identified in the northern area and 153 taxa in the southern area. In both areas, the taxonomic composition of the nano- and micro-phytoplankton guilds exhibited greater temporal than spatial variation. The latter was much higher in the southern area than in the northern area (average dissimilarity between stations being 70.7±0.8% and 44.7±4.2% respectively). 4.Primary productivity varied in space and time on the gradients considered. Phytoplankton species richness and diversity exhibited significant patterns of variation in space and time; overall, these were inversely related to the primary productivity patterns in the northern area, whereas they were directly related in the southern area. 5.The small individual size and the high turnover rate of phytoplankton are likely to underlie the observed relationships, which emphasized a threshold response to nutrient enrichment in agreement with the ,paradox of enrichment'. Under resource enrichment conditions, the high turnover of producers leads to hierarchical partitioning of the available resources with an increasing dominance of a few species. Therefore, the relationship observed here seems likely to be explained by the complementarity hypothesis. Copyright © 2003 John Wiley & Sons, Ltd. [source] | ||||||||||