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1.
Ann Neurol ; 93(3): 427-430, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36546649

RESUMO

The subspecialty of experimental neurotherapeutics trains neurologists in discovering and developing new treatments for neurologic diseases. Based on development of exciting new treatments for genetic and inflammatory diseases, we predict that there will be many other breakthroughs. The job market has expanded rapidly in academia, the pharmaceutical industry, government, and not-for-profit sectors; many new opportunities can be anticipated. The burgeoning opportunities in the field mandate that training address the challenges of overcoming obstacles in therapeutic discovery, implementation science, and development of affordable and equitably available treatments. ANN NEUROL 2023;93:427-430.


Assuntos
Indústria Farmacêutica , Ondas de Maré , Humanos
2.
Harmful Algae ; 119: 102324, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36344196

RESUMO

Green tides, which are widespread problems, are harmful issues that affect the protection of ocean ecosystems and natural resources. Scientific assessment and prevention of the green tides are essential for sustainable planning and the utilization of maritime traffic, tourism, and industry. However, the suitable or risk habitats and their dominant factors of green tides from global perspective are unknown. Here, this study proposed a novel framework to show the habitat suitability and risk of ocean green tides by considering marine environmental factors (i.e., sea surface temperature, sea surface salinity, solar irradiance, chlorophyll-a concentration, and sea surface wind). Through global remote sensing images and marine environmental factor data, this study found that (1) suitable and at-risk green tides areas are located in the north and south temperate zones; (2) marine physical factors are expected to weaken the green tide risk globally and enhance the green tide risk in coastal areas; (3) the green tides in the North Atlantic Ocean and the West Pacific Ocean are dominated by environmental factors and physical factors, respectively; and (4) when reducing carbon to promote sustainability, more potentially suitable green tide areas may appear at high latitudes. The results demonstrate the at-risk location and future trend of green tides, which are helpful for sustainable planning of ocean ecosystems.


Assuntos
Ecossistema , Ondas de Maré , Oceano Atlântico , Oceano Pacífico , Vento
3.
PLoS One ; 17(2): e0263416, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35202425

RESUMO

The Above Ground Biomass (AGB) of seaweeds is the most fundamental ecological parameter as the material and energy basis of intertidal ecosystems. Therefore, there is a need to develop an efficient survey method that has less impact on the environment. With the advent of technology and the availability of popular filming devices such as smartphones and cameras, intertidal seaweed wet biomass can be surveyed by remote sensing using popular RGB imaging sensors. In this paper, 143 in situ sites of seaweed in the intertidal zone of GouQi Island, ShengSi County, Zhejiang Province, were sampled and biomass inversions were performed. The hyperspectral data of seaweed at different growth stages were analyzed, and it was found that the variation range was small (visible light range < 0.1). Through Principal Component Analysis (PCA), Most of the variance is explained in the first principal component, and the load allocated to the three kinds of seaweed is more than 90%. Through Pearson correlation analysis, 24 parameters of spectral features, 9 parameters of texture features (27 in total for the three RGB bands) and parameters of combined spectral and texture features of the images were selected for screening, and regression prediction was performed using two methods: Random Forest (RF), and Gradient Boosted Decision Tree (GBDT), combined with Pearson correlation coefficients. Compared with the other two models, GBDT has better fitting accuracy in the inversion of seaweed biomass, and the highest R2 was obtained when the top 17, 17 and 11 parameters with strong correlation were selected for the regression prediction by Pearson's correlation coefficient for Ulva australis, Sargassum thunbergii, and Sargassum fusiforme, and the R2 for Ulva australis was 0.784, RMSE 156.129, MAE 50.691 and MAPE 28.201, the R2 for Sargassum thunbergii was 0.854, RMSE 790.487, MAE 327.108 and MAPE 19.039, and the R2 for Sargassum fusiforme was 0.808, RMSE 445.067 and MAPE 28.822. MAE was 180.172 and MAPE was 28.822. The study combines in situ survey with machine learning methods, which has the advantages of being popular, efficient and environmentally friendly, and can provide technical support for intertidal seaweed surveys.


Assuntos
Biomassa , Ecossistema , Tecnologia de Sensoriamento Remoto , Alga Marinha/crescimento & desenvolvimento , Humanos , Aprendizado de Máquina , Análise de Componente Principal , Ondas de Maré
4.
Artigo em Inglês | MEDLINE | ID: mdl-33207680

RESUMO

Seaports' energy strategy should rely on the use of renewable energy. Presently, the share of renewable energy used by many of the ports worldwide is negligible. Some initiatives are in the process of implementation to produce some of the energy used by the Port of Valencia, one the largest ports in the Mediterranean Basin. Among these initiatives, a photovoltaic plant with an installed capacity of 5.5 MW is under a tendering process and the assessment studies for the deployment of three to five windmills are close to being finished. However, this is not enough to make it a "zero emissions port" as some of the energy demand would still be covered by fossil fuels. Therefore, we should consider clean alternative energy sources. This article analyses the wave energy resources in the surroundings of the Port of Valencia using a 7-year series of data obtained from numerical modelling (forecast). The spatial distribution of wave power is analysed using data from 3 SIMAR points at Valencia Bay and is compared to the data obtained by the Valencia Buoy I (removed in 2005). The obtained results are used to estimate the power matrices and the average energy output of two wave energy converters suitable to be integrated into the port's infrastructure. Finally, the wave energy converters' production is compared to the average amount of energy that is forecast to be obtained from other renewable sources such as solar and wind. Due to the nature of the Gulf's wave climate (mostly low waves), the main conclusion is that the energy obtainable from the waves in the Valencia Gulf will be in correlation with such climate. However, when dealing with great energy consumers every source of production is worthwhile and further research is needed to optimize the production of energy from renewable sources and its use in an industrial environment such as ports.


Assuntos
Fontes Geradoras de Energia , Energia Renovável , Ondas de Maré , Eletricidade , Fontes Geradoras de Energia/normas , Oceanos e Mares
5.
Microb Ecol ; 77(4): 852-865, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30852639

RESUMO

Irradiance and temperature variations during tidal cycles modulate microphytobenthic primary production potentially by changing the radiative energy balance of photosynthetic mats between immersion and emersion and thus sediment daily net metabolism. To test the effect of tidal stages on the radiative energy budget, we used microsensor measurements of oxygen, temperature, and scalar irradiance to estimate the radiative energy budget in a coastal photosynthetic microbial mat during immersion (constant water column of 2 cm) and emersion under increasing irradiance. Total absorbed light energy was higher in immersion than emersion, due to a lower reflectance of the microbial mat, while most (> 97%) of the absorbed light energy was dissipated as heat irrespective of tidal conditions. During immersion, the upward heat flux was higher than the downward one, whereas the opposite occurred during emersion. At highest photon irradiance (800 µmol photon m-2 s-1), the sediment temperature increased ~ 2.5 °C after changing the conditions from immersion to emersion. The radiative energy balance showed that less than 1% of the incident light energy (PAR, 400-700 nm) was conserved by photosynthesis under both tidal conditions. At low to moderate incident irradiances, the light use efficiency was similar during the tidal stages. In contrast, we found an ~ 30% reduction in the light use efficiency during emersion as compared to immersion under the highest irradiance likely due to the rapid warming of the sediment during emersion and increased non-photochemical quenching. These changes in the photosynthetic efficiency and radiative energy budget could affect both primary producers and temperature-dependent bacterial activity and consequently daily net metabolism rates having important ecological consequences.


Assuntos
Fenômenos Fisiológicos Bacterianos , Sedimentos Geológicos/microbiologia , Água do Mar/microbiologia , Luz Solar , Ondas de Maré , Dinamarca
6.
PLoS One ; 13(8): e0200368, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30110331

RESUMO

Prioritization of marsh-management strategies is a difficult task as it requires a manager to evaluate the relative benefits of each strategy given uncertainty in future sea-level rise and in dynamic marsh response. A modeling framework to evaluate the costs and benefits of management strategies while accounting for both of these uncertainties has been developed. The base data for the tool are high-resolution uncertainty-analysis results from the SLAMM (Sea-Level Affecting Marshes Model) under different adaptive-management strategies. These results are combined with an ecosystem-valuation assessment from stakeholders. The SLAMM results and stakeholder values are linked together using "utility functions" that characterize the relationship between stakeholder values and geometric metrics such as "marsh area," marsh edge," or "marsh width." The expected-value of each site's ecosystem benefits can then be calculated and compared using estimated costs for each strategy. Estimates of optimal marsh-management strategies may then be produced, maximizing the "ecosystem benefits per estimated costs" ratio.


Assuntos
Conservação dos Recursos Naturais/economia , Análise Custo-Benefício , Ecossistema , Água do Mar/análise , Ondas de Maré , Áreas Alagadas , Incerteza
7.
Artigo em Inglês | MEDLINE | ID: mdl-29966359

RESUMO

Public health risks from urban floods are a global concern. A typhoon is a devastating natural hazard that is often accompanied by heavy rainfall and high storm surges and causes serious floods in coastal cities. Affected by the same meteorological systems, typhoons, rainfall, and storm surges are three variables with significant correlations. In the study, the joint risk of rainfall and storm surges during typhoons was investigated based on principal component analysis, copula-based probability analysis, urban flood inundation model, and flood risk model methods. First, a typhoon was characterized by principal component analysis, integrating the maximum sustained wind (MSW), center pressure, and distance between the typhoon center and the study area. Following this, the Gumbel copula was selected as the best-fit copula function for the joint probability distribution of typhoons, rainfall, and storm surges. Finally, the impact of typhoons on the joint risk of rainfall and storm surges was investigated. The results indicate the following: (1) Typhoons can be well quantified by the principal component analysis method. (2) Ignoring the dependence between these flood drivers can inappropriately underestimate the flood risk in coastal regions. (3) The co-occurrence probability of rainfall and storm surges increases by at least 200% during typhoons. Therefore, coastal urban flood management should pay more attention to the joint impact of rainfall and storm surges on flood risk when a typhoon has occurred. (4) The expected annual damage is 0.82 million dollars when there is no typhoon, and it rises to 3.27 million dollars when typhoons have occurred. This indicates that typhoons greatly increase the flood risk in coastal zones. The obtained results may provide a scientific basis for urban flood risk assessment and management in the study area.


Assuntos
Tempestades Ciclônicas/estatística & dados numéricos , Planejamento em Desastres/métodos , Chuva , Ondas de Maré/estatística & dados numéricos , China , Cidades , Inundações/economia , Modelos Teóricos , Análise Multivariada , Medição de Risco
8.
PLoS One ; 13(5): e0197170, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29771961

RESUMO

Recent studies in coastal wetlands have indicated that consumers may play an important role in regulating large-scale ecosystem processes. Predator removal experiments have shown significant differences in above-ground biomass production in the presence of higher level consumers, or predators. These results indicate that predators play an important role in regulating biomass production, but the extent to which this regulation impacts additional ecosystem functions, such as nutrient cycling and organic matter accumulation, is unclear. This study evaluated the impact that consumers have on large-scale ecosystem processes within southern New England tidal wetlands and contributes to the general understanding of trophic control in these systems. I established enclosure cages within three coastal wetlands and manipulated the presence of green crab predators to assess how trophic interactions affect ecosystem functions. Findings suggest that although these consumers may exert some top-down effects, other environmental factors, such as other consumers not studied here or bottom-up interactions, may variably play a larger role in the maintenance of ecosystem processes within the region. These results indicate that the loss of top-down control as an important mechanism influencing ecosystem functions may not hold for all wetlands along the full extent of the New England coastline.


Assuntos
Biomassa , Participação da Comunidade , Ondas de Maré , Áreas Alagadas , Animais , Humanos , New England
9.
J Hum Evol ; 92: 101-115, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26989020

RESUMO

The south coast of South Africa provides the earliest evidence for Middle Stone Age (MSA) coastal resource exploitation by early Homo sapiens. In coastal archaeology worldwide, there has been a debate over the general productivity of intertidal foraging, leading to studies that directly measure productivity in some regions, but there have been no such studies in South Africa. Here we present energetic return rate estimates for intertidal foraging along the southern coast of South Africa from Blombos Cave to Pinnacle Point. Foraging experiments were conducted with Khoi-San descendants of the region, and hourly caloric return rates for experienced foragers were measured on 41 days near low tide and through three seasons over two study years. On-site return rates varied as a function of sex, tidal level, marine habitat type and weather conditions. The overall energetic return rate from the entire sample (1492 kcal h(-1)) equals or exceeds intertidal returns reported from other hunter-gatherer studies, as well as measured return rates for activities as diverse as hunting mammals and plant collecting. Returns are projected to be exceptionally high (∼ 3400 kcal h(-1) for men, ∼ 1900 kcal h(-1) for women) under the best combination of conditions. However, because of the monthly tidal cycle, high return foraging is only possible for about 10 days per month and for only 2-3 h on those days. These experiments suggest that while intertidal resources are attractive, women and children could not have subsisted independently, nor met all their protein-lipid needs from marine resources alone, and would have required substantial additional energy and nutrients from plant gathering and/or from males contributing game.


Assuntos
Comportamento Apetitivo , Metabolismo Energético , Adolescente , Adulto , Idoso , Arqueologia , Criança , Pré-Escolar , Feminino , Humanos , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Frutos do Mar , África do Sul , Ondas de Maré , Adulto Jovem
10.
PLoS One ; 10(2): e0117030, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25710497

RESUMO

Conventionally flood mapping typically includes only a static water level (e.g. peak of a storm tide) in coastal flood inundation events. Additional factors become increasingly important when increased water-level thresholds are met during the combination of a storm tide and increased mean sea level. This research incorporates factors such as wave overtopping and river flow in a range of flood inundation scenarios of future sea-level projections for a UK case study of Fleetwood, northwest England. With increasing mean sea level it is shown that wave overtopping and river forcing have an important bearing on the cost of coastal flood events. The method presented converts inundation maps into monetary cost. This research demonstrates that under scenarios of joint extreme surge-wave-river events the cost of flooding can be increased by up to a factor of 8 compared with an increase in extent of up to a factor of 3 relative to "surge alone" event. This is due to different areas being exposed to different flood hazards and areas with common hazard where flood waters combine non-linearly. This shows that relying simply on flood extent and volume can under-predict the actual economic impact felt by a coastal community. Additionally, the scenario inundation depths have been presented as "brick course" maps, which represent a new way of interpreting flood maps. This is primarily aimed at stakeholders to increase levels of engagement within the coastal community.


Assuntos
Desastres/economia , Inundações/economia , Inglaterra , Modelos Teóricos , Medição de Risco , Ondas de Maré
11.
ScientificWorldJournal ; 2013: 906180, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23476152

RESUMO

Concern over global climate change as a result of fossil fuel use has resulted in energy production from renewable sources. Marine renewable energy devices provide clean electricity but can also cause physical disturbance to the local environment. There is a considerable paucity of ecological data at potential marine renewable energy sites that is needed to assess potential future impacts and allow optimal siting of devices. Here, we provide a baseline benthic survey for the Big Russel in Guernsey, UK, a potential site for tidal energy development. To assess the suitability of proposed sites for marine renewable energy in the Big Russel and to identify potential control sites, we compared species assemblages and habitat types. This baseline survey can be used to select control habitats to compare and monitor the benthic communities after installation of the device and contribute towards the optimal siting of any future installation.


Assuntos
Biota , Conservação de Recursos Energéticos/métodos , Ecossistema , Monitoramento Ambiental/métodos , Animais , Organismos Aquáticos/fisiologia , Peixes/fisiologia , Biologia Marinha/métodos , Análise Multivariada , Oceanos e Mares , Energia Renovável , Ondas de Maré , Gravação em Vídeo/métodos
12.
Med Sport Sci ; 58: 80-97, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22824840

RESUMO

The objective of this review was to summarize the epidemiological literature for surfboard riding (surfing), kite surfing and personal watercraft (PWC) riding injuries and describe the incidence and nature of these injuries, common risk factors, and strategies for prevention. The databases searched for relevant publications included Medline, ScienceDirect, ProQuest International, PubMed, Academic Search Premier as well as Google Scholar to identify additional, non-indexed studies. Overall, there was a lack of good quality descriptive studies for these three sports and many of the studies reviewed involved the use of administrative datasets or case-series designs. Among the few studies to provide incidence estimates, there were inconsistencies in how injury was defined, the inclusion criteria, and the reporting of incidence rates, making comparisons within and between the sports difficult. While the reported incidence rates were generally low, head and lower extremity injuries were common across all three sports. Only two studies reported evidence for postulated risk factors. Bigger waves and surfing over rock or reef sea floor increased the risk of injury among competitive surfers, while older age and having more experience increased the risk of significant injuries among recreational surfers. No evaluations of preventative measures were identified. This review demonstrates the need for well-designed epidemiological research, especially studies that focus on the accurate measurement and description of incidence, nature, severity and circumstances of injuries. Once this has occurred, interventions targeted at reducing the incidence of injuries among these sports can be designed, implemented and evaluated.


Assuntos
Traumatismos em Atletas/epidemiologia , Ondas de Maré , Vento , Traumatismos em Atletas/economia , Traumatismos Craniocerebrais/economia , Traumatismos Craniocerebrais/epidemiologia , Humanos , Incidência , Escala de Gravidade do Ferimento , Extremidade Inferior/lesões , Oceanos e Mares , Fatores de Risco
13.
Ecotoxicology ; 21(7): 1998-2003, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22661316

RESUMO

The Comet assay is finding increasing application as a biomarker assay for the genotoxic potential of contaminants in field transplantation experiments involving mussels. Especially in estuaries, habitats that are of particular concern, environmental variables, such as salinity, can vary significantly. Although hinted at in the literature, there is a lack of clarification as to whether changes in salinity or emersion-induced hypoxia have the potential to alter background DNA damage in mussels, thus masking the extent of potential genotoxic effects following exposure to environmental contaminants. The present study exposed Mytilus edulis in the laboratory to static salinities (25, 50, 75, and 100 %) for 72 h. Mussels were also subjected to simulated tidal cycles, including periods of emersion, for 72 h. None of these treatments resulted in a significant change in the level of DNA damage expressed as % tail DNA. These experiments demonstrate that salinity, within the limits of the concentrations tested, and temporary emersion are not confounding factors for Comet assay data derived from M. edulis.


Assuntos
Ensaio Cometa/normas , Dano ao DNA , Mytilus edulis/genética , Salinidade , Ondas de Maré , Animais , Monitoramento Ambiental/métodos , Estuários , Concentração Osmolar
14.
Accid Anal Prev ; 46: 45-51, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22310042

RESUMO

The objective of this research was to evaluate a campaign to improve beachgoer recognition of calm-looking rip currents, known to contribute to surf drowning. Posters, postcards, and brochures conveying the message "Don't get sucked in by the rip" were distributed in an intervention area. Beachgoers were interviewed in this and a similar control area one year before and immediately after the intervention (respective response rates: 69.9% and 82.3%), Consenting respondents were sent follow-up questionnaires after approximately 6 months and 55% responded. In the intervention area, 28.8% of post-intervention, and 57.2% of follow-up respondents, had seen our campaign. At post-intervention, intervention respondents demonstrated improvement (relative to baseline) in intentions to swim away from a calm-looking rip, ability and confidence in identifying a rip, intention never to swim at unpatrolled beaches, and responses to being caught in a rip, compared to the control respondents. Similar improvements were observed post-intervention for respondents in the intervention area who had seen our campaign (relative to those who had not), and at 6 month follow-up for intervention respondents (relative to control respondents). The relatively brief print-based campaign was effective in warning beachgoers about calm-looking rips.


Assuntos
Prevenção de Acidentes/métodos , Acidentes/estatística & dados numéricos , Afogamento/prevenção & controle , Prevenção Primária/métodos , Desenvolvimento de Programas , Avaliação de Programas e Projetos de Saúde , Adolescente , Adulto , Coleta de Dados , Afogamento/epidemiologia , Feminino , Educação em Saúde , Conhecimentos, Atitudes e Prática em Saúde , Promoção da Saúde , Humanos , Masculino , Pessoa de Meia-Idade , New South Wales/epidemiologia , Oceanos e Mares , Segurança/estatística & dados numéricos , Marketing Social , Estatística como Assunto , Inquéritos e Questionários , Ondas de Maré , Fatores de Tempo , Adulto Jovem
15.
Water Sci Technol ; 62(9): 2037-43, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21045329

RESUMO

The aim of the study was to carry out water quality assessment and to identify sources responsible for deterioration of quality in the Malad creek, Mumbai, India. Creek receives sewage and wastewater from various drains and partially treated effluent from Malad and Versova treatment facilities. To assess the water quality, sampling locations were identified in the creek based on discharges of wastewater and sewage. Identified locations were traced in physical space by a global positioning system. Samples were collected during low and high tides and analyzed for physical, chemical and bacteriological parameters such as pH, Turbidity, DO, BOD, NH(3)-N, PO(4) and FC and compared with SW-II Standards. Parameters were also analyzed statistically and correlated to determine the relationship amongst the parameters using SPSS software. The idea was to determine the probable causes contributing to the pollution in the creek. Various options were suggested for improvement in the creek quality based on water quality assessment.


Assuntos
Rios/química , Água do Mar , Esgotos , Ondas de Maré , Abastecimento de Água/normas , Monitoramento Ambiental/métodos , Concentração de Íons de Hidrogênio , Índia , Microbiologia da Água , Poluentes Químicos da Água
16.
Environ Toxicol Chem ; 29(5): 1172-81, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20821555

RESUMO

Groundwater contaminated with volatile chlorinated hydrocarbons (VCHs) was identified as discharging to Penrhyn Estuary, an intertidal embayment of Botany Bay, New South Wales, Australia. A screening-level hazard assessment of surface water in Penrhyn Estuary identified an unacceptable hazard to marine organisms posed by VCHs. Given the limitations of hazard assessments, the present study conducted a higher-tier, quantitative probabilistic risk assessment using the joint probability curve (JPC) method that accounted for variability in exposure and toxicity profiles to quantify risk (delta). Risk was assessed for 24 scenarios, including four areas of the estuary based on three exposure scenarios (low tide, high tide, and both low and high tides) and two toxicity scenarios (chronic no-observed-effect concentrations [NOEC] and 50% effect concentrations [EC50]). Risk (delta) was greater at low tide than at high tide and varied throughout the tidal cycle. Spatial distributions of risk in the estuary were similar using both NOEC and EC50 data. The exposure scenario including data combined from both tides was considered the most accurate representation of the ecological risk in the estuary. When assessing risk using data across both tides, the greatest risk was identified in the Springvale tributary (delta=25%)-closest to the source area-followed by the inner estuary (delta=4%) and the Floodvale tributary (delta=2%), with the lowest risk in the outer estuary (delta=0.1%), farthest from the source area. Going from the screening level ecological risk assessment (ERA) to the probabilistic ERA changed the risk from unacceptable to acceptable in 50% of exposure scenarios in two of the four areas within the estuary. The probabilistic ERA provided a more realistic assessment of risk than the screening-level hazard assessment.


Assuntos
Hidrocarbonetos Clorados/química , Hidrocarbonetos Clorados/toxicidade , Rios/química , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/toxicidade , Ecossistema , Monitoramento Ambiental , New South Wales , Oceanos e Mares , Ondas de Maré , Poluentes Químicos da Água/química , Poluentes Químicos da Água/toxicidade
17.
Sci Total Environ ; 408(20): 4784-94, 2010 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-20659759

RESUMO

The short-lived natural radionuclides (7)Be (T(1/2)=53 days), (234)Th(xs) (T(1/2)=24.1 days) and (210)Pb(xs) (T(1/2)=22.3 years), i.e. (234)Th and (210)Pb in excesses of that supported within particles by the decay of their parent isotopes, were analysed in suspended particulate matter (SPM) to study the particle dynamics in the Gironde fluvial estuarine system (France), strongly impacted by heavy metal pollution. From surveys of this land-ocean interface in 2006 and 2007, we established a times series of these radioisotopes and of their activity ratios ((7)Be/(210)Pb(xs) and (234)Th/(210)Pb(xs) ARs) in particles sampled under different hydrological conditions. The particulate (7)Be/(210)Pb(xs) AR varies along the fluvial estuarine system mainly due to variations in (7)Be activities, controlled by riverine, oceanic and atmospheric inputs and by resuspension of old (7)Be-deficient sediments. These processes vary with river discharge, tidal cycle and season. Therefore, seasonal particle transport processes can be described using variations of the SPM (7)Be/(210)Pb(xs) ARs. During high river discharge, the SPM (7)Be/(210)Pb(x) ARs decrease from river to the ocean. The turbidity maximum zone (TMZ) is dispersed and the particles, and the associated contaminants, are rapidly transported from river to coastal waters, without significant retention within the TMZ. During low river discharge, the TMZ intrudes into the fluvial estuary, and the lowest (7)Be/(210)Pb(x) ARs are observed there due to resuspension of (7)Be-deficient sediments. Away from the TMZ, from the middle to lower estuary, SPM (7)Be/(210)Pb(x) ARs increase, indicating that the particles have been recently tagged with (7)Be. We explain this trend as being caused by marine input of dissolved radionuclides, as traced by SPM (234)Th/(210)Pb(xs) ARs, followed by scavenging in the estuary. This result indicates that particle transport models based on (7)Be and trace-metal budgets must consider oceanic dissolved inputs as an additional source of (7)Be and, possibly, of contaminants to estuaries.


Assuntos
Berílio/análise , Radioisótopos de Chumbo/análise , Material Particulado/análise , Tório/análise , Ondas de Maré , Poluentes Radioativos da Água/análise , Monitoramento Ambiental/métodos , França , Água Doce/química , Cinética , Radioisótopos de Chumbo/química , Material Particulado/química , Traçadores Radioativos , Radioisótopos/análise , Chuva/química , Estações do Ano , Água do Mar/química , Movimentos da Água , Poluentes Radioativos da Água/química
18.
Environ Manage ; 45(5): 1014-26, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-18523822

RESUMO

The coastal landscapes in southwestern Korea include a diverse array of tidal wetlands and salt marshes. These coastal zones link the ecological functions of marine tidal wetlands and freshwater ecosystems with terrestrial ecosystems. They are rich in biological diversity and play important roles in sustaining ecological health and processing environmental pollutants. Korean tidal wetlands are particularly important as nurseries for economically important fishes and habitats for migratory birds. Diking, draining, tourism, and conversion to agricultural and urban uses have adversely affected Korean tidal wetlands. Recent large development projects have contributed to further losses. Environmental impact assessments conducted for projects affecting tidal wetlands and their surrounding landscapes should be customized for application to these special settings. Adequate environmental impact assessments will include classification of hydrogeomorphic units and consideration of their responses to biological and environmental stressors. As is true worldwide, Korean laws and regulations are changing to be more favorable to the conservation and protection of tidal wetlands. More public education needs to be done at the local level to build support for tidal wetland conservation. Some key public education points include the role of tidal wetlands in maintaining healthy fish populations and reducing impacts of nonpoint source pollution. There is also a need to develop procedures for integrating economic and environmental objectives within the overall context of sustainable management and land uses.


Assuntos
Conservação dos Recursos Naturais/métodos , Monitoramento Ambiental/métodos , Ondas de Maré , Áreas Alagadas , Biodiversidade , Conservação dos Recursos Naturais/economia , Conservação dos Recursos Naturais/legislação & jurisprudência , Monitoramento Ambiental/economia , Monitoramento Ambiental/legislação & jurisprudência , Geografia , Regulamentação Governamental , Hidrobiologia , República da Coreia
19.
Disasters ; 34(2): 328-36, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19863569

RESUMO

Following a major disaster, microfinance institutions (MFIs) often face high levels of bad debt, which may require the institutions to be recapitalised. This paper describes a recapitalisation programme implemented by the SANASA movement of Sri Lanka in 390 microfinance societies following the December 2004 tsunami, and highlights lessons for other similar programmes. MFI recapitalisation is a good use of funds in post-disaster situations. To create successful programmes, donors should expect to relax some of their usual project requirements and MFIs should focus on maintaining credit discipline.


Assuntos
Desastres/economia , Administração Financeira/métodos , Socorro em Desastres/economia , Ondas de Maré/economia , Humanos , Estudos de Casos Organizacionais , Sri Lanka
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