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Macroinvertebrados como bioindicadores em riacho tropical: uma avaliação de impactos por sedimentação, rompimento de barragem e de recuperação após medidas de restauração / Macroinvertebrates as bioindicators in tropical stream: an evaluation of impacts by sedimentation, dam rupture, and recuperation after restoration project applicationThandy Junio da Silva Pinto 07 February 2018 (has links)
Alterações antrópicas em ecossistemas aquáticos exigem medidas de recuperação dos ambientes degradados, destacando-se projetos de restauração ecológica. Uma das etapas cruciais nesses projetos é a fase de monitoramento, sendo que o uso de macroinvertebrados como bioindicadores apresenta-se como uma importante ferramenta, por eles oferecerem vantagens sobre outros métodos de avaliação. Assim, o objetivo foi verificar os efeitos do assoreamento, antes e depois do rompimento da barragem de um pequeno reservatório em um riacho tropical, sobre a assembleia de macroinvertebrados aquáticos e avaliar a resposta da estrutura da comunidade após a implementação de um projeto de restauração ecológica. A pesquisa foi conduzida no riacho da Campininha, que passou por diversas alterações antrópicas, destacando-se aqui o rompimento de uma barragem e posteriormente a todos esses distúrbios pela implementação de um projeto de restauração ecológica. Foi realizada revisões da literatura para verificação da aplicabilidade da comunidade de macroinvertebrados como bioindicadores de sedimentação e na avaliação de projetos de restauração ecológica. Foram coletados dados pré-existentes antes e após o acidente e realizadas campanhas amostrais dois anos após o início da implantação do projeto de restauração. A comunidade de macroinvertebrados foi avaliada pela aplicação de índices ecológicos estruturais e funcionais alimentares e os resultados analisados por meio de ferramentas de estatística uni e multivariada. A análise da literatura mostrou que a aplicação de índices ecológicos tradicionais, tais como riqueza e diversidade, podem não ser sensíveis o suficiente para indicar impactos relacionados à sedimentação e implementação de projetos de restauração ecológica. Sendo, assim, necessária a utilização de índices que considerem a composição da comunidade, a sensibilidade dos organismos e a utilização de grupos funcionais alimentares e suas relações. Antes do rompimento da barragem a comunidade de macroinvertebrados já apresentava-se empobrecida pelo assoreamento do trecho represado e do canal fluvial. O rompimento da estrutura implicou na perda de importantes grupos e na mudança da composição da comunidade, além da perda de grupos funcionais alimentares, com consequente perda de funções ambientais. Após a implementação do projeto de restauração houve o aparecimento de 20 famílias, no entanto, os índices ecológicos tradicionais não foram capazes de identificar mudanças na comunidade. Métricas de composição e de grupos alimentares apontaram para um processo de recuperação da área. As características do sedimento tiveram um alto poder explicativo da comunidade, mostrando que a recuperação do habitat bentônico é um dos fatores que leva à uma melhor resposta da comunidade, mesmo esse não tendo sido o foco da aplicação do projeto de restauração avaliado. O relativo curto período transcorrido após a implementação do projeto já foi suficiente para indicar melhorias na qualidade ambiental. Tais resultados contrapõe a maioria dos estudos verificados na revisão da literatura. No entanto destaca-se que os mesmos foram conduzidos principalmente em ambientes temperados, indicando que em ambientes tropicais a dinâmica de recuperação é diferente. Assim aponta-se a necessidade da intensificação da implantação de projetos e monitoramento dos mesmos para a criação de um arcabouço teórico para auxiliar gestores e projetistas na sua elaboração. / Anthropic alterations in aquatic ecosystems demand the implementation of recuperation actions, highlighting ecological restoration projects. The monitoring is an important step to these projects, and the macroinvertebrates application as bioindicators is an important tool, because they are advantageous in comparison to another assessment methods. Thus, the goal was verify the effects of silting, and dam rupture in macroinvertebrate community, in a tropical stream, and assess the answer to an ecological restoration project implementation. The research was conducted in the Campininha stream, that was impacted by anthropic alterations, featured a dam rupture and after all this disturbances was implemented an ecological restoration project. A literature review was conducted to verification of the applicability of macroinvertebrates as bioindicators of silting and in ecological restoration projects assessment. Data was collected before and after the dam rupture, and samplings were done two years after the project implementation began. The macroinvertebrates community was assessed by application of structural and functional feeding indexes and the results analyzed by univariate and multivariate statistic. The literature review showed that the traditional indexes application may be not sensible to indicate impacts related to silting and ecological restoration projects implementation, and it is necessary the utilization of indexes that consider the community composition, organisms sensibility and functional feeding groups and your relations. Before the dam rupture, the macroinvertebrate community was already poor by the silting of the lake and fluvial channel. The dam rupture leaded to the loss of important groups and in the change of the macroinvertebrate community composition, also loss of functional feeding groups and consequently environmental functions. After the ecological restoration project implementation were found another 20 families, however, the traditional indexes were not sensible to indicate changes in macroinvertebrates community. Composition and functional feeding groups indexes showed the stream recuperation process. The sediment characteristics had a community high explanative power showing that the benthic habitat recovery is a factor that guide to a better community answer, even this was not the goal of the restoration project application. The relative short time after the project implementation was enough to point a environmental quality recovery, in contrast with the literature review. However the most studies analyzed was conducted in temperate environments, showing that in tropical environments the recovery dynamics is different. Thus, is necessary a intensification of restoration projects implementation and monitoring to a creation of data bases to guide managers and professionals responsible by the projects elaboration in decision make.
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Várzeas urbanas: uma abordagem ecológica aplicada para o seu manejo / Urban wetlands: an applied ecological approach for their managementSilva, Fabio Leandro da 07 February 2018 (has links)
As áreas de várzea estão entre os ecossistemas mais ameaçados, porém no Brasil essa situação agrava-se devido à falta de uma abordagem ecológica robusta na Lei de Proteção da Vegetação Nativa, o que torna necessário a atuação do poder público municipal para salvaguardar esses sistemas. A presente pesquisa empregou uma abordagem ecológica aplicada (limnologia, macroinvertebrados, macrófitas aquáticas) para avaliar a relação do rio Sorocaba com suas várzeas no município de Sorocaba, o uso e ocupação da terra e a sua influência sobre às variáveis limnológicas, além das demandas dos serviços ambientais fornecidos pelas várzeas ao município. Duas amostragens foram realizadas durante o ano de 2017, sendo uma no período de cheia (fevereiro) e outra na estiagem (junho). Métodos padronizados foram empregados para o desenvolvimento do presente trabalho. Evidenciou-se que a poluição orgânica e o predomino de áreas antropizadas são os principais fatores responsáveis pela alteração das variáveis limnológicas analisadas. Alguns serviços ambientais (i.e. provisão de água, controle do fluxo, regulação dos processos erosivos, regulação de nutrientes, ciclagem da água, pesca voltada ao lazer e valor intrínseco da biodiversidade) prestados pelos ecossistemas de várzea do Município de Sorocaba apresentam um balanço negativo (i.e. demanda superior à oferta). As espécies de macrófitas e famílias de macroinvertebrados encontradas são espécies indicadoras de poluição orgânica. Por fim, destaca-se a contribuição da ação estratégica e o papel da gestão municipal para o manejo dos ecossistemas de várzea. / The wetlands are among the most threatened ecosystems, although in the Brazil that situation is worse because of an ecological approach lack in the Law of Native Vegetation Protection, what makes necessary the public power action to safeguard those systems. The present research employed an applied ecological approach (limnology, macroinvertebrates, aquatic macrophytes) for Sorocaba River and its wetlands assessment in Sorocaba-SP municipality, the land cover and its influence on limnological variables, as well as the environmental services demand supplied by the municipality wetlands. Two samples were performed during 2017, one during the rainy (February) season and other on the dry season (June). Patronized methods were employed in the present research. The organic pollution and the anthropic areas predominance are the mainly factors responsible for limnological variables alteration. Some environmental services (i.e. water provision, water flow control, erosive process control, nutrient control, water cycling, recreation fishing and biodiversity intrinsic value) provided by the studied wetlands showed a negative balance (i.e. demand superior to the provision capacity). The macrophyte species and macroinvertebrate families found are organic pollution indicators. Finally, stand out the strategic action contribution and the municipality governance role for wetlands ecosystem management.
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Analyse der Erosionsdynamik im Einzugsgebiet des Landwassers (Oberlausitz) – Einfluss auf Gewässergüte und MakrozoobenthosdriftKändler, Matthias 09 January 2012 (has links)
In der vorliegenden Arbeit werden für ein stark anthropogen beeinflusstes Einzugsgebiet die komplexen Zusammenhänge zwischen Witterung, Landnutzung, Erosion, Gerinneabfluss, Stofffrachten und Makrozoobenthos analysiert. Dafür wurde eine Messstation eingerichtet, an der Fließgeschwindigkeit, Trübung, pH Wert und Leitfähigkeit kontinuierlich gemessen wurden. Mit Hilfe eines durchflussgesteuerten Probennehmers wurden Wasserproben entnommen und im Labor auf verschiedene Inhaltsstoffe (Nährstoffe, Schwermetalle) analysiert sowie die Konzentration von Feinsediment bestimmt. Es konnte eine Beziehung zwischen Trübung und Sedimentkonzentration abgeleitet werden.
Die chemischen Analysen zeigten einen komplexen Zusammenhang zwischen der Erosion von landwirtschaftlichen Flächen, dem Stoffeintrag von versiegelten Arealen (Verkehrsflächen, Dächer) aber auch witterungs- und vegetationsbedingte saisonale Effekte. Ein Vergleich der Eigenschaften der Schwebstoffe/Feinsediment im Landwasser mit denen von Ackerboden (Maisfelder) zeigte, dass diese die „chemische Handschrift“ der Ackerböden trugen.
Mit Hilfe der Modelle EROSION 3D und ICECREAM wurden die abgetragenen Bodenmengen für das Einzugsgebiet bzw. für ausgewählte Hänge quantifiziert. EROSION 3D überschätzt den Bodenaustrag aus dem Untersuchungsgebiet deutlich. Das Modell ist ungeeignet, um für das Einzugsgebiet reale Abtragswerte mit den zur Verfügung stehenden flächenhaften Eingangsdaten zu berechnen. Bereits für Einzelhänge werden zu große Bodenabträge berechnet. Verstärkend kommt hinzu, dass auf Grund der Modellannahme jeder Partikel, der das Gewässer erreicht auch aus dem Einzugsgebiet heraustransportiert wird. Das Modell kann empfohlen werden, um erosionsgefährdete Flächen auszuweisen.
In der Untersuchungsperiode von 2009 bis Juli 2011 wurde an Hand von 57 Driftfängen mit unterschiedlichen hydrologischen Randbedingungen die Wirkung der Fließgeschwindigkeit auf den Übergang benthischer Invertebraten in die freie Welle identifiziert. Aus Uferbereichen gelangen zufällig terrestrische Invertebraten in das Gewässer, deren Anteil sich durch gewässernahen Oberflächenabfluss in Folge von Niederschlagsereignissen erhöht. Die Driftdichte nimmt ab Fließgeschwindigkeiten von 0,3 m/s deutlich zu. Oligochaeta, Cyclopoida und Dipolstraca driften verstärkt bei Fließgeschwindigkeiten >0,6 m/s.
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Effects of Global Warming on Phytoplankton and its Biocontrol in Large Rivers: Insights from a Model AnalysisRuiz Albizuri, José Ricardo 03 July 2018 (has links)
Benthic filter feeders (BFF) can reduce phytoplankton concentration (abundance) thereby controlling eutrophication in several ecosystems, including rivers. However, experiments suggest warming can alter the relationship between BFF grazing rate and the growth rate of (heterotrophic) planktonic prey. To investigate how eutrophication control by grazers is altered with temperature under the influence of other important abiotic (water depth, and speed, light, and turbidity) and biotic factors (initial phytoplankton concentration [hereafter: Pin value], BFF density and spatial BFF distribution), we developed a spatially-explicit computer simulation model. This model simulates the dynamics of a phytoplankton population traveling through a simplified river channel while being grazed by BFF. Our model includes the thermal responses of BFF grazing and phytoplankton growth. The results show that BFF grazing can qualitatively alter and, in some circumstances, even reverse the response of phytoplankton to warming. Moreover, the response of grazer-controlled phytoplankton to warming, water depth and Pin value is non-linear and phytoplankton can increase steeply with slight changes within some ranges of these variables. In addition, these variables can interact causing their combined effects on eutrophication to differ from what is expected considering their isolated effects. Generally, the effect of most variables, including temperature, Pin value and BFF density and spatial distribution, is larger at shallow waters. Moreover, our study shows that phytoplankton control can be substantially improved by heterogeneous BFF distributions where the BFF are located at the extremes of the river either upstream or downstream instead of homogenously distributed along the whole river. However, warming can cause a switch between these two optimal distributions or even can cause differences among the spatial distributions to disappear. In general, the homogeneous BFF distribution can be used as conservative estimate of eutrophication control. In conclusion, this work shows that trophic control can qualitatively alter the response of eutrophication to warming, supporting previous studies suggesting that the prediction of global warming effects requires considering not only the thermal responses of organisms but also their trophic interactions. In addition to these biotic variables, this thesis reveals that considering the interactions between abiotic and biotic variables and including their spatial distribution are important for eutrophication control. Especially, the detection of thresholds in the response of grazer-controlled phytoplankton to temperature, water depth, Pin value, and spatial BFF distribution indicates that one should be careful with predictions because of potential abrupt changes. Although further studies are needed to make specific recommendations for water quality management, our work provides preliminary suggestions on the conditions where grazers or Pin reductions can be more efficient to control eutrophication.
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Shallow- water hardbottom communities support the separation of biogeographic provinces on the west- central Florida Gulf CoastEagan, Shelby 24 July 2019 (has links)
Several studies have found separation of biogeographic provinces on the West Florida Shelf (WFS), but the location of this separation differs depending on different organisms with faunal boundaries proposed at Apalachicola, Cedar Key, Anclote Key. Tampa Bay, Charlotte Harbor, Cape Romano, or Cape Sable. Biogeographic boundaries can be gradual over a given space and are often species-specific. Analyses of marine benthic mapping and community characterization of Florida’s West-central coast shallow water (depth) hardbottom habitats indicate a major shift in the benthos across Tampa Bay. Quantitative benthic surveys of 29 sites yielded a total of 4,079 individuals of nine stony coral species and 1,918 soft coral colonies. Populations were dominated by four species of corals: Siderastrea radians, Oculina robusta, Solenastrea hyades, and Cladacora arbuscula. Most corals were less than 10 cm in diameter. Cluster analyses of coral density and major functional group percent cover showed distinct differences in hard and soft coral densities and species demographics from south to north with clear spatial patterns between regions. These benthic hardbottom coral communities change over a relatively small spatial scale (10’s of km), indicating a biogeographical province or ecosystem region boundary in marine benthic communities at, or very near, the mouth of Tampa Bay. Broader studies are needed to identify the shifts in benthic community biogeography along the West Florida Shelf.
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Automated mapping of oblique imagery collected with unmanned vehicles in coastal and marine environmentsFreeman, Jacob B. 12 May 2023 (has links) (PDF)
Recent technological advances in unmanned observational platforms, including remotely operated vehicles (ROVs) and small unmanned aerial systems (sUAS), have made them highly effective tools for research and monitoring within marine and coastal environments. One of the primary types of data collected by these systems is video imagery, which is often captured at an angle oblique to the Earth’s surface, rather than normal to it (e.g., downward looking). This thesis presents a newly developed suite of tools designed to digitally map oblique imagery data collected with ROV and sUAS in coastal and marine environments and quantitatively evaluates the accuracy of the resultant maps. Results indicate that maps generated from oblique imagery collected with unmanned vehicles have highly variable accuracy relative to maps generated with imagery data collected with conventional mapping platforms. These results suggest that resultant maps have the potential to match or even surpass the accuracy of maps generated with imagery data collected with conventional mapping platforms but realizing that potential is largely dependent upon careful survey design.
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FACTORS CONTROLLING NICKEL BIOAVAILABILITY AND EFFECTS ON BENTHIC INVERTEBRATES IN HARDWATER FRESHWATER STREAMSCuster, Kevin Wayne January 2012 (has links)
No description available.
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Long-Term Surface Uplift History of the Active Banda Arc-Continent Collision: Depth and Age Analysis of Foraminifera from Rote and Savu Islands, IndonesiaRoosmawati, Nova 06 July 2005 (has links) (PDF)
Analysis of foraminifera for synorogenic pelagic units of Rote and Savu Islands, Indonesia, reveals high rates of surface uplift in the past 1.5 Ma of the incipient Banda arc-continent collision. Paleodepth estimates are derived from benthonic forams and ages from planktonic forams. But estimates are complicated, however, by abundant reworking; yet several distinctive species have been found. Synorogenic deposits in western Rote yield forams of biozone Neogene (N) 18 and depths from 5000-5700 meters at the base of the section, and 3600 meters at the top of the section. Eastern Rote yields forams of N 19/20 - N 22 and depths from 5400-5700 meters. Central Rote yields N 21 and depths from 5000-5700 meters. Because all of the sections are presently about the same elevation (~200 m), long-term surface uplift rates are slightly higher (1.84-3.29 m/yr) in eastern and central Rote than those in western Rote. Forams from Savu yield ages of N19/20 - N 22. Across Savu depth estimates range from 3200-5700 meters, which yields a range of uplift rates from 1.86 mm/yr in SE Savu to 3.25 mm/yr in Central Savu. These results indicate the Banda arc-continent collision caused uplift of Rote and Savu at rates of 1-2 mm/yr over the past 3 Ma.
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The implications of co-locating marine protected areas around offshore wind farmsAshley, Matthew January 2014 (has links)
Offshore wind farm (OWF) construction in the UK is progressing rapidly alongside increasing spatial pressures on marine ecosystems and social and economic activities. A need for increased protection of habitats, species and ecological processes that support environmental and economic benefits is being met by designation of marine protected areas (MPAs). Mitigation and spatial planning solutions are required to enable protection of vital ecological habitats, features and processes and support sustainable economic development. A potential solution is to co-locate OWFs and MPAs. This study uses a multi-disciplinary approach to examine if evidence on the environmental effects of existing OWFs and associated effects on fishing activity (as an existing resource use) benefits MPA goals. Through a systematic review and meta-analyses of existing data, knowledge of OWF effects on species abundance and economic effects on fishing were identified as key evidence gaps. The ecological evidence need was approached through a case study of ecological effects of North Hoyle OWF, North Wales, UK, using existing pre and post-construction monitoring data, as well as primary baited remote underwater video data, collected 5 years later (8 years post-construction). Results suggested habitat and species recovered to a stable state that showed some community differences to pre-construction conditions. The presence of OWF monopiles is likely to have increased existing heterogeneity of substratum and increased opportunities for scavenging species. Species benefitting and disadvantaged by habitat provided within the OWF reflected meta-analyses trends. Extended baseline monitoring to provide confident identification of natural levels of variation in sediment and fauna was lacking. Analysis of fishing activity and landings before and after OWF construction in three UK case study regions approached effects on resource users. Fishing activity in the three case study areas showed broad scale similarity to national trends. Small-scale activity patterns indicated greater reductions in mobile (towed) fishing gear effort near to operating OWFs than in static gear activity (using pots or static nets). Semi-structured interviews conducted with fishermen in each region revealed loss of ground and disruption as negative effects from OWFs, in addition to existing pressures. Benefits including habitat creation and species augmentation, as well as reduction of cumulative lost ground, were identified by fishermen from co-location of MPAs and OWFs. Ecological effects of OWFs suggested benefits from habitat creation, species augmentation and potential for protection of sandbank habitats between monopiles. Mitigation requirements were identified to maximise these potential benefits to an MPA network.
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The Relationship between Near Shore Hardbottom Exposure and Benthic Community Composition and Distribution in Palm Beach County, FLCumming, Kristen A 07 March 2017 (has links)
Anthropogenic changes to the landscape, storm events and sea level rise are contributing to the erosion of beaches leading to an increase of the sediment load in near shore marine environments. Palm Beach, Florida is host to unique near shore hardbottom habitats. These areas are distinct from the vast expanses of surrounding sediments and play and important role of habitat and shelter for many different species. In this study, remotely sensed images from 2000-2015 were used to look at the movement of sediment and how it contributes to exposure rates of near shore hardbottom habitats in Palm Beach, Florida and how these factors affect the benthic community.
GIS was used to determine areas of hardbottom with high exposure (exposed in >60% of aerial images), medium exposure (40-60%), and low exposure (
I strived to determine if one can detect a successional relationship of benthic communities in a dynamic environment with annual mapping. I also examined if areas with higher exposure rates have more complex successive communities than those with lower exposure rates, and what implications this has on near shore benthic communities. In situ surveys conducted at 117 sites determined the community structure (corals, octocorals, macroalgae, and hydroids).
This study confirmed that periodic mapping was successful in identifying hardbottom burial and exposure, which fluctuate both spatially and temporally. This periodic mapping along with manual delineation did identify hardbottom burials and exposures that fluctuate between years and relate to benthic community differences. The near shore hardbottom coral reef communities aligned with the observed exposure categories with the greater coral species richness and octocoral morphologies found at sites classified as highly exposed. Statistical analyses showed differences in communities shallower and deeper than three meters’ depth. Increasing the frequency of imagery captures and in situ observation would further increase our comprehension of the metrics of hardbottom exposures in reference to community structure.
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