4,819 research outputs found
The spatial and temporal structure of hydrographic and phytoplankton biomass heterogeneity along the Catalan coast (NW Mediterranean)
The horizontal and temporal distribution of hydrographic properties and phytoplankton biomass along the Catalan coast were analyzed to determine their variance structure (i.e., variance partition between temporal, alongshore, and across-shore components), and the relationship between hydrographic heterogeneity and variability in phytoplankton biomass. Temporal chlorophyll variability was highly seasonal, but horizontal biomass variability was related to hydrographic variability, as evidenced by significant correlations to temperature and salinity. The strength of chlorophyll-salinity correlations changed according to the extent of riverine influences within the area, but significant correlations were always negative, indicating enhanced phytoplantkon growth due to river runoff. Temperature-chlorophyll correlations changed seasonally, from highly positive in early summer to negative by late summer. In addition, horizontal biomass patterns were dominated by an onshore-offshore decrease, which were altered by modifications of water circulation associated to topographic features such as canyons and shelf concavities
Corrigendum: Resolving the abundance and air-sea fluxes of airborne microorganisms in the North Atlantic Ocean
We found an implementation error in the calculation of the deposition velocity (vd) which, in turn, affected all the estimated vd-depending parameters (deposition flux, residence time, and traveled distance by microorganisms). Deposition fluxes are now somewhat lower than previously estimated, resulting in residence times and traveled distances longer than those previously estimated. In addition, the spray fluxes were calculated using a spray generation function (dF/dr0) valid for droplets of radii between 0.5 and 12 μm proposed by Blanchard (1963) and Gathman (1982) as corrected by Andreas et al. (1995). However, in the calculation of dF/dr0, we exceeded this valid range of radii given that we included droplets with radii from 0.2 μm according to the small size of some microbial cells. Thus, a different formulation of dF/dr0, developed by Gong (2003), is now used for the estimation of spray fluxes of microbes, which is valid even for small droplets from a radius of 0.07 μm.
Below, we offer a new corrected version of the paragraphs affected by corrections along the text. In addition, we show corrected versions of Figure 1 (forward trajectories according residence times), Figure 3 (deposition velocity values), Figure 5 (spray and deposition fluxes), Figure 6 (Net fluxes), and Table 1. The authors apologize for the errors in the estimates reported in the original manuscript. These corrections only affect the magnitude of some of the reported variables and even though they do not change the scientific conclusions of the article they are reported here for accuracy and reproducibility.En prens
Does the energy label (EL) matter in the residential market?: a stated preference analysis in Barcelona
Energy performance in buildings has become a milestone in EU environmental policy in the last 15 years. Nonetheless, in some countries such as Spain the full acceptance of the Energy Performance of Buildings Directive is still relatively rare and novel, with little evidence as to how relevant it is in the real estate market. There are different reasons for this phenomenon: on the one hand, the real estate crisis has paralyzed the completion of most of the works in new/refurbished efficient buildings (which renders it impossible to use revealed preference methods); on the other hand, information is not complete and the consumer's perception of the relevant cost/benefits could be incorrect. For this reason, assessing the trade-off between the energy label and other specific attributes of the housing market has become important. To that end, a choice experiment following an RPL (Random Parameter Logit) model was employed. This form is suitable to accommodate various empirical situations where the assumptions of the Conditional Logit model have to be relaxed. Results suggest that the Energy Label (EL) does matter in the real estate market in relation to other residential attributes. Marginal willingness to pay for anPostprint (published version
Is global ocean sprawl a cause of jellyfish blooms?
Jellyfish (Cnidaria, Scyphozoa) blooms appear to be increasing in both intensity and frequency in many coastal areas worldwide, due to multiple hypothesized anthropogenic stressors. Here, we propose that the proliferation of artificial structures – associated with (1) the exponential growth in shipping, aquaculture, and other coastal industries, and (2) coastal protection (collectively, “ocean sprawl”) – provides habitat for jellyfish polyps and may be an important driver of the global increase in jellyfish blooms. However, the habitat of the benthic polyps that commonly result in coastal jellyfish blooms has remained elusive, limiting our understanding of the drivers of these blooms. Support for the hypothesized role of ocean sprawl in promoting jellyfish blooms is provided by observations and experimental evidence demonstrating that jellyfish larvae settle in large numbers on artificial structures in coastal waters and develop into dense concentrations of jellyfish-producing polyps
El cambio climático y sus consecuencias para los ecosistemas costeros de las Islas Baleares
El cambio climático es el problema medioambiental más importante del siglo XXI, afectando a todas las actividades humanas, incluídas la provisión de agua y alimento para la humanidad. Este cambio afectará de manera particularmente importante a las áreas insulares, ya que tienen una mayor dependencia de las zonas costeras, las cuales se veran fuertemente afectadas por el cambio climático. Esta dependencia se materializa, en el caso de las Islas Baleares, en una dependencia económica, derivada del papel clave de la industria turística. Esta industria es especialmente sensible al cambio climático, por 10 que las consecuencias para los ecosistemas costeros que se discuten en este capítulo tendran también importantes repercusiones sobre la economia y sociedad baleares. En este capítulo examinamos primero los conceptos de cambio climático y cambio global, revisamos las consecuencias de los cambios que se han producido durante el siglo XX para los ecosistemas costeros y finalmente evaluamos los cambios adicionales que se esperan sobre la base de las predicciones de escenarios posibles para el siglo XXI, y las actuaciones que debieran emprenderse para minimizar las consecuencias negativas del cambio climático. Todo este ejercicio se lleva a cabo bajo una notable carència de datos específicos para las Islas Baleares, 10 que revela de inmediato la necesidad de contar con una base observacional, sujeta a un control de calidad riguroso, capaz de permitir, a traves de su integración en un sistema interdisciplinar de analisis, la deteccion de cambios en los ecosistemas costeros de las Islas Baleares.El canvi climàtic és el problema mediambiental més important del segle XXI, afectant a totes les activitats humanes, incloses la provisió d'aigua i aliment per a la humanitat. Aquest canvi afectarà de forma particularment important a les àees insulars, ja que tenen una major dependència de les zones costeres, que es veuran intensament afectades pel canvi climàtic. Aquesta dependència es materialitza, en el cas de les Illes Balears, en una dependència econòmica, derivada del paper clau de la industria turística. Aquesta industria es especialment sensible al canvi climàtic, pel que les conseqüències per als ecosistemes costaners que se discuteixen en aquest capítol tendran també importants repercusions sobre l'economia i la societat de les Balears. En aquest capítol s'examinen primer els conceptes de canvi climátic i canvi global, revisam les conseqüències dels canvis que s'han produït durant el segle XX per als ecosistemes costaners i finalment avaluam els canvis addicionals que s'esperen sobre la base de les prediccions d'escenaris possibles per al segle XXI, i les actuacions que es tendrien que emprendre per a minimitzar les conseqüències negatives del canvi climàtic. Tot aquest exercici es du a terme sota una notable carència de dades especifiques per a les Illes Balears, el que revela la necessitat de comptar amb una base observacional, subjecta a un control de qualitat rigurós, capaç de permetre, a través de la seva integració en un sistema interdisciplinar d'anàlisi, la detecció de canvis en els ecosistemes costaners de les Illes Balears.The climatic change is the most relevant environmental problem of the XXI century, affecting all human activities, including water and food supplies to mankind. This change will dramatically affect insular areas, since they have a greater dependence on coastal areas that will be strongly affected by the climatic change. In the case of the Balearic Islands, this dependence will be mainly economical, derived from its key role on the tourist industry. This industry is specially sensitive to the climatic change, and therefore aftermath for coastal ecosystems discussed in this chapter will also have important effects on the Balearic economy and society. In this chapter the concepts of climatic and global change will be examined first, consequences of changes suffered by coastal ecosystems through the XX century will be revised, and finally we will evaluate the added changes that can be expected based on the different scenarios predicted for the XXI century, and the actions to undertake to minimize the negative consequences of the climatic change. All this exercise is done under a remarkable lack of specific data for the Balearic Islands, thereby revealing the need to count with an observational basis, subject to a thorough quality control, able to permit, through its integration in an interdisciplinary analysis system, the detection of changes in the coastal ecosystems of the Balearic Islands
Endophytic bacterial community of a Mediterranean marine angiosperm (Posidonia oceanica)
Bacterial endophytes are crucial for the survival of many terrestrial plants, but little is known about the presence and importance of bacterial endophytes of marine plants. We conducted a survey of the endophytic bacterial community of the long-living Mediterranean marine angiosperm Posidonia oceanica in surface-sterilized tissues (roots, rhizomes, and leaves) by Denaturing Gradient Gel Electrophoresis (DGGE). A total of 26 Posidonia oceanica meadows around the Balearic Islands were sampled, and the band patterns obtained for each meadow were compared for the three sampled tissues. Endophytic bacterial sequences were detected in most of the samples analyzed. A total of 34 OTUs (Operational Taxonomic Units) were detected. The main OTUs of endophytic bacteria present in P. oceanica tissues belonged primarily to Proteobacteria (α, γ, and δ subclasses) and Bacteroidetes. The OTUs found in roots significantly differed from those of rhizomes and leaves. Moreover, some OTUs were found to be associated to each type of tissue. Bipartite network analysis revealed differences in the bacterial endophyte communities present on different islands. The results of this study provide a pioneering step toward the characterization of the endophytic bacterial community associated with tissues of a marine angiosperm and reveal the presence of bacterial endophytes that differed among locations and tissue types
Educação e literacia sexual: representações de professores (estudo de caso)
A Lei n.º 60/2009 generalizou a Educação Sexual (ES) nas escolas do ensino básico e secundário. Os modelos de ES caracterizam diferentes posições perante a sexualidade, sejam socioeconómicas, profissionais ou religiosas. Hoje, a ES tem como desafio a promoção de competências, baseadas na responsabilidade e na autonomia, para usar o conhecimento e estimular o desenvolvimento pessoal. A capacidade de aplicar o conhecimento e as aptidões, para analisar, raciocinar e comunicar eficazmente, interpretar e resolver problemas em situações variadas é hoje indispensável. A ES deve seguir uma orientação baseada na literacia sexual ou ser um receituário de prevenção e saúde pública?
Num estudo de caso, verificou-se que para os professores inquiridos a educação da sexualidade de crianças até aos 11/12 anos deve valorizar conhecimentos (gerais básicos) sob supervisão dos pais, complementada pela escola, em contexto estruturado, o que corresponde ao previsto no nível 1 do QEQ (EU, 2008). A partir dos 12 anos os professores inquiridos continuam a valorizar o papel educativo dos pais em relação à sexualidade, considerando, no entanto, que deve haver um certo grau de autonomia e responsabilidade por parte dos alunos, o que corresponde ao previsto no nível 2 do QEQ. Globalmente os professores inquiridos apontam para uma educação sexual baseada no modelo de formação pessoal e social, reforçando-se progressivamente a autonomia e a responsabilidade dos alunos para a literacia sexual
Anomalies in the carbonate system of Red Sea coastal habitats
© The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Baldry, K., Saderne, V., McCorkle, D. C., Churchill, J. H., Agust, S., & Duarte, C. M. Anomalies in the carbonate system of Red Sea coastal habitats. Biogeosciences, 17(2), (2020): 423-439, doi:10.5194/bg-17-423-2020.We use observations of dissolved inorganic carbon (DIC) and total alkalinity (TA) to assess the impact of ecosystem metabolic processes on coastal waters of the eastern Red Sea. A simple, single-end-member mixing model is used to account for the influence of mixing with offshore waters and evaporation–precipitation and to model ecosystem-driven perturbations on the carbonate system chemistry of coral reefs, seagrass meadows and mangrove forests. We find that (1) along-shelf changes in TA and DIC exhibit strong linear relationships that are consistent with basin-scale net calcium carbonate precipitation; (2) ecosystem-driven changes in TA and DIC are larger than offshore variations in >70 % of sampled seagrass meadows and mangrove forests, changes which are influenced by a combination of longer water residence times and community metabolic rates; and (3) the sampled mangrove forests show strong and consistent contributions from both organic respiration and other sedimentary processes (carbonate dissolution and secondary redox processes), while seagrass meadows display more variability in the relative contributions of photosynthesis and other sedimentary processes (carbonate precipitation and oxidative processes). The results of this study highlight the importance of resolving the influences of water residence times, mixing and upstream habitats on mediating the carbonate system and coastal air–sea carbon dioxide fluxes over coastal habitats in the Red Sea.This research has been supported by the King Abdullah University of Science and Technology (KAUST) (grant nos. BAS/1/1071-01-01 and BAS/1/1072-01-01) and the Investment in Science fund at WHOI
Fairy circle landscapes under the sea
Short-scale interactions yield large-scale vegetation patterns that, in turn,
shape ecosystem function across landscapes. Fairy circles, which are circular
patches bare of vegetation within otherwise continuous landscapes, are
characteristic features of semiarid grasslands. We report the occurrence of
submarine fairy circle seascapes in seagrass meadows and propose a simple model
that reproduces the diversity of seascapes observed in these ecosystems as
emerging from plant interactions within the meadow. These seascapes include two
extreme cases, a continuous meadow and a bare landscape, along with
intermediate states that range from the occurrence of persistent but isolated
fairy circles, or solitons, to seascapes with multiple fairy circles, banded
vegetation, and "leopard skin" patterns consisting of bare seascapes patterns
consisting of bare seascapes dotted with plant patches. The model predicts that
these intermediate seascapes extending across kilometers emerge as a
consequence of local demographic imbalances along with facilitative and
competitive interactions among the plants with a characteristic spatial scale
of 20 to 30 m, consistent with known drivers of seagrass performance. The
model, which can be extended to clonal growth plants in other landscapes
showing fairy rings, reveals that the different seascapes observed hold
diagnostic power as to the proximity of seagrass meadows to extinction points
that can be used to identify ecosystems at risks
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