As part of a biodiversity study on intertidal invertebrates, several sea anemones from the west coast of the Baja California Peninsula were collected in June 2016. The taxonomic features of four ...specimens agree well with those of the species Anthopleura radians, a recently described sea anemone from northern Chile. This study is the first published report on this species outside the range of distribution documented in the original description, including new images of A. radians' external and internal features and complete characterization of their cnidae. Differences between A. radians from other species of the genus reported from the eastern Pacific are also discussed.
Increasing anthropogenic pressures urge enhanced knowledge and understanding of the current state of marine biodiversity. This baseline information is pivotal to explore present trends, detect future ...modifications and propose adequate management actions for marine ecosystems. Coralligenous outcrops are a highly diverse and structurally complex deep-water habitat faced with major threats in the Mediterranean Sea. Despite its ecological, aesthetic and economic value, coralligenous biodiversity patterns are still poorly understood. There is currently no single sampling method that has been demonstrated to be sufficiently representative to ensure adequate community assessment and monitoring in this habitat. Therefore, we propose a rapid non-destructive protocol for biodiversity assessment and monitoring of coralligenous outcrops providing good estimates of its structure and species composition, based on photographic sampling and the determination of presence/absence of macrobenthic species. We used an extensive photographic survey, covering several spatial scales (100s of m to 100s of km) within the NW Mediterranean and including 2 different coralligenous assemblages: Paramuricea clavata (PCA) and Corallium rubrum assemblage (CRA). This approach allowed us to determine the minimal sampling area for each assemblage (5000 cm(2) for PCA and 2500 cm(2) for CRA). In addition, we conclude that 3 replicates provide an optimal sampling effort in order to maximize the species number and to assess the main biodiversity patterns of studied assemblages in variability studies requiring replicates. We contend that the proposed sampling approach provides a valuable tool for management and conservation planning, monitoring and research programs focused on coralligenous outcrops, potentially also applicable in other benthic ecosystems.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Primary production in the eutrophic Baltic Sea is limited by nitrogen availability; hence denitrification (natural transformation of nitrate to gaseous N₂ ) in the sediments is crucial in mitigating ...the effects of eutrophication. This study shows that dissimilatory nitrate reduction to ammonium (DNRA) process, where nitrogen is not removed but instead recycled in the system, dominates nitrate reduction in low oxygen conditions (O₂ <110 μM), which have been persistent in the central Gulf of Finland during the past decade. The nitrogen removal rates measured in this study show that nitrogen removal has decreased in the Gulf of Finland compared to rates measured in mid-1990s and the decrease is most likely caused by the increased bottom water hypoxia.
O objetivo deste trabalho foi proporcionar aos alunos do ensino médio a compreensão das principais comunidades de macroinvertebrados que habitam as macrófitas e o sedimento de um igarapé no sul do ...estado do Amazonas. Foram selecionados 10 alunos que se destacaram na disciplina de Biologia, os quais acompanharam todo o processo de estudo dos macroinvertebrados em passos como coleta, triagem e identificação. As macrófitas foram coletadas como auxílio de um quadrado vazado de 0,09 m2 e uma draga tipo Van Veen com área de pegada de 0,025 m2. Ao todo foram identificados nas macrófitas e no sedimento cinco taxa: Chironomidae, Coleoptera, Hemiptera, Odonata e Oligochaeta. Concluímos que o projeto possibilitou aos alunos um maior conhecimento da fauna de macroinvertebrados que vivem no igarapé localizado bem próximo à escola participante do projeto, assim como um maior entendimento dos conceitos sobre Limnologia. Este projeto poderá estimular os alunos em atividades de pesquisa, assim como demonstrar a importância da fauna local para a preservação dos ecossistemas aquáticos.
The over-all aim of the book is to collect and add to the information published already on the larger benthic foraminifera and in cases their associated algae. Many decades of research in the Far ...East, to some extent in the Middle East and Americas has lead to numerous articles with confused systematics. Therefore, with the aid of new and precise age dates, from calcareous nannofossils and Sr isotopes, the current schemes of the larger foraminifera in a relatively precise chronostratigraphic and sequence stratigraphic framework are revised. This is achieved by: 1) establishing the systematic and occurrences of larger foraminifera from carbonate rocks in successions covering the Carboniferous to Miocene, with careful taxonomic comparison with the known records in the different bioprovinces; 2) illustration fossils of different families and groups at generic levels. 3) illustrations of important species and comparing distributions of different taxa.The inventory of larger benthic foraminifera focuses on the main important groups and the illustration of their genera. Reviews of the global state of the art of each group are complemented with the new data, and the direct palaeobiogeographic relevance of the new data is analyzed.
* A unique, comprehensive reference work on the larger foraminifera.* A documentation of the biostratigraphic ranges and palaeoecological significance of larger foraminifera which is essential for understanding many major oil-bearing sedimentary basins.*The palaeogeographic interpretations of the shallow marine late Palaeozoic to Cenozoic world.
When sudden catastrophic events occur, it becomes critical for coastal communities to detect and respond to environmental transformations because failure to do so may undermine overall ecosystem ...resilience and threaten people's livelihoods. We therefore asked how capable of detecting rapid ecological change following massive environmental disruptions local, indigenous people are. We assessed the direction and periodicity of experimental learning of people in the Western Solomon Islands after a tsunami in 2007. We compared the results of marine science surveys with local ecological knowledge of the benthos across 3 affected villages and 3 periods before and after the tsunami. We sought to determine how people recognize biophysical changes in the environment before and after catastrophic events such as earthquakes and tsunamis and whether people have the ability to detect ecological changes over short time scales or need longer time scales to recognize changes. Indigenous people were able to detect changes in the benthos over time. Detection levels differed between marine science surveys and local ecological knowledge sources over time, but overall patterns of statistically significant detection of change were evident for various habitats. Our findings have implications for marine conservation, coastal management policies, and disaster‐relief efforts because when people are able to detect ecological changes, this, in turn, affects how they exploit and manage their marine resources. Detección del Cambio Ecológico Rápido por la Población Indígena
Benthic foraminiferal assemblages of a drill core from the lower Guadalquivir Basin (northern Gulf of Cádiz, SW Spain) have been analyzed in order to reconstruct the paleoenvironmental evolution in ...the vicinity of the Betic seaways during the Messinian. The core consists of marine sediments ranging from the latest Tortonian to the early Pliocene. Changes in the abundance of certain marker species, planktonic/benthic ratio (P/B ratio), paleodepth estimated with a transfer function, content of sand grains and presence of glauconitic layers indicate a complete transgressive–regressive sea-level cycle from the bottom to the top of the section. An abrupt sea-level rise, from inner-middle shelf to middle slope, is recorded at the lowermost part of the core (latest Tortonian–earliest Messinian), followed by a relatively rapid shallowing from middle slope to outer shelf. Magnetobiostratigraphic data show that this sea-level fall postdates the onset of the Messinian salinity crisis (MSC) in the Mediterranean. Finally, the early Pliocene deposits are interpreted as inner-middle shelf.
Changes in the benthic foraminiferal assemblages through the core are mainly controlled by the trophic conditions, specifically by the quantity and quality of the organic matter reaching the sea floor. The upper slope and part of the outer shelf assemblages are highly diverse and dominated by shallow infaunal species, indicating a generally mesotrophic environment with moderate oxygenation. These environments have likely been affected by repeated upwelling events, documented by increased abundance of Uvigerina peregrina s.l., an opportunistic species thriving in environments with enhanced labile organic matter supply. The assemblages of the transitional interval between upper slope to outer shelf, and of the outer shelf are generally characterized by a relatively low diversity and epifaunal-shallow infaunal taxa, indicating oligotrophic and well-oxygenated conditions. The inner-middle shelf assemblages are characterized by very low diversity and dominance of intermediate to deep infaunal taxa, suggesting an eutrophic environment with low oxygen content. These assemblages are dominated by Nonion fabum and Bulimina elongata, two taxa that are able to feed from continental low-quality organic matter, most likely derived from river run-off. The paleoenviromental evolution on the Atlantic side of Betic and Rifian seaways is similar during the Messinian, with a Messinian continuous sea-level lowering driven by regional tectonic uplift and upwelling-related waters reaching the upper slope. This study will further contribute to understand the role of tectonics on the sea-level changes as well as on the closure of the Atlantic–Mediterranean gateways that led to the MSC, and on the paleoceanography on the Atlantic sides of these corridors.
► We study Messinian benthic foraminifera from the lower Guadalquivir Basin. ► Paleodepth analyses show a transgressive–regressive cycle from the bottom to the top. ► Trophic conditions and bottom oxygenation controlled the assemblages. ► Similar paleoenvironmental evolution is observed in NW Morocco. ► Tectonic and sea-level evolution that led the Messinian salinity crisis is analyzed.
El río Chico, ubicado en el centro de Santa Cruz, recorre 600 km desde sus nacientes hasta sudesembocadura. En su tramo medio, se encuentra la localidad de Gobernador Gregores(48°45'3"S, 70°14'54"O), ...que ejerce su influencia sobre el río a través de las actividadesagropecuarias y el vertido de efluentes urbanos. Con el objetivo de conocer el grado deimpacto sobre la calidad del agua del río, se realizó un análisis de la comunidad demacroinvertebrados bentónicos y se calculó el índice Biotic Monitoring Patagonian Streams(BMPS). En marzo de 2017, se efectuó un primer relevamiento en seis estaciones de muestreodispuestas en un diseño de gradiente de impacto, con dos estaciones control aguas arriba de lalocalidad y cuatro estaciones aguas abajo. En cada estación se tomaron muestras de agua paraanálisis fisicoquímicos, se registraron datos ambientales mediante sonda multiparamétrica yse recolectaron cuatro muestras de macrobentos utilizando una red Surber con malla de 0,5mm de abertura. Los organismos recolectados fueron identificados y contabilizados bajomicroscopios estereoscópico y óptico. Para cada muestra se calculó el número de taxones (S),la abundancia total (N), la diversidad (H’) y la equitatividad (J); los datos de abundancia seanalizaron utilizando estadística multivariada. Se identificaron 25 taxones, siendo los mejorrepresentados los oligoquetos Naididae, los hirudíneos, los moluscos Chilinidae yLymnaeidae, y los insectos Chironomidae, Baetidae y Glossosomatidae. En las estacionesubicadas aguas abajo más cercanas a la localidad, la comunidad se encontró dominadaampliamente por oligoquetos y quironómidos, y presentó los valores más bajos de S, H’ y J.Los valores de BMPS en esas estaciones indicaron la existencia de aguas contaminadas afuertemente contaminadas. En las estaciones control y las más alejadas aguas abajo, losvalores de S, H’ y J aumentaron significativamente y el índice BMPS indicó mejorescondiciones en la calidad ambiental del río.
Here we compare the applicability, the information provided and the cost-benefit of three sampling methods usually used in the study of rocky benthic assemblages. For comparative purposes, sampling ...was performed seasonally and along a depth gradient (0-50 m) in the Cabrera Archipelago (western Mediterranean). The destructive scraping (collection) method was the least cost-effective but provided the best qualitative and quantitative information. The in situ visual method was the most time-effective but provided low levels of taxonomic resolution and its accuracy decreased with depth due to the increasing difficulty of recognizing species in situ due to nitrogen narcosis, reduced light and cold. The photoquadrat method showed intermediate values of cost-effectiveness and information but was not suitable for multilayered assemblages, as it only accounted for the overstory. A canonical correspondence analysis showed that depth was highlighted as the main environmental gradient (16.0% of variance) by the three methods. However, differences due to the sampling method (7.9% of variance) were greater than differences due to temporal variability (5.8% of variance), suggesting that the three methods are valid but their selection has to be carefully assessed in relation to the targeted assemblages and the specific goals of each study.
El cometido de esta publicación es presentar los resultados parciales del proyecto «La ciudad inteligente; un palimpsesto digital», actualmente en etapa de desarrollo. Dicho proyecto ahonda en el ...incipiente paradigma de las Smart cities desde una perspectiva territorial, trascende la noción atemporal y dicotómica ciudad–campo para hacer foco en el territorio como paisaje cultural integral. La reflexión, pero sobre todo la experimentación en instrumentos tecnológicos concretos de base social aplicados al territorio constituyen una herramienta indispensable a la hora de construir la realidad de la ciudad inteligente. A partir del diseño y puesta en marcha de un plan estratégico de acción pensado para ser completado en cuatro años, esta publicación aborda los objetivos, el sustrato teórico, los instrumentos utilizados y los resultados parciales de la experiencia llevada a cabo en el Paisaje Industrial Fray Bentos, recientemente declarado «Patrimonio de la Humanidad» por UNESCO.
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