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Davis, Ryan Scott. "An ecological risk assessment for mosquito insecticides." Thesis, Montana State University, 2007. http://etd.lib.montana.edu/etd/2007/davis/DavisR0507.pdf.
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Hazlerigg, Charles Rupert Edward. "Fish population ecology and ecological risk assessment." Thesis, Imperial College London, 2012. http://hdl.handle.net/10044/1/9678.
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Density-dependent processes are crucial in the regulation of fish populations and strongly influence their resilience to exploitation and exposure to toxic chemicals. Multiple density-dependent processes occur at different stages in the life-cycle of fish, and a general pattern of such processes in the ontogeny of fish has been suggested but not clearly demonstrated in natural populations. This thesis aimed to provide a detailed experimental assessment of density-dependent processes through the entire life-cycle, using laboratory and semi-natural populations of zebrafish, Danio rerio, and to explore the implications of these processes for the ecological risk assessment of endocrine disrupting chemicals using an individual-based population model. Results clearly demonstrate the importance of density-dependent mortality in the early juvenile life-stage and density-dependent growth in the late juvenile and adult life-stages consistent with evidence from wild populations of much larger wild species, suggesting the existence of general ontogenetic patterns of density dependence that are invariant to maximum size. Patterns of density dependence found in populations of zebrafish under semi-natural conditions in Bangladesh were similar to those observed in the laboratory, except that the absolute strength of density dependence was higher and consequently, carrying capacity lower, by about two orders of magnitude in the semi-natural populations. A conclusion from these studies is that these patterns of density dependence are applicable generally across the teleost taxa due to developmental similarities. The population model incorporating these patterns of density dependence showed that density dependence compensated for reasonably high levels of disruption for many individual-level endpoints currently used in risk assessment, including fecundity and sex ratio. This indicates that current risk assessment practices are highly conservative and the inclusion of population models such as developed here for zebrafish, could enhance the scientific basis and ecological realism of laboratory derived data used in risk analysis.
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Pokhrel, Lok R., and Phillip R. Scheuerman. "Ecological Risk Assessment of Zinc Oxide Nanoparticles." Digital Commons @ East Tennessee State University, 2012. https://dc.etsu.edu/etsu-works/2962.
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Pokhrel, Lok R., Brajesh Dubey, and Phillip R. Scheuerman. "Ecological Risk Assessment of Zinc Oxide Nanoparticles." Digital Commons @ East Tennessee State University, 2012. https://dc.etsu.edu/etsu-works/2951.
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Chen, Limei. "Nonparametric assessment of safety levels in ecological risk assessment (ERA)." FIU Digital Commons, 2003. http://digitalcommons.fiu.edu/etd/2135.
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In ecological risk assessment (ERA), it is important to know whether the exposure that animal species receive from a chemical concentration exceeds the desired safety level. This study examined several statistical methods currently being used in ecological risk assessment and reviewed several statistical procedures related to this subject in the literature. Two large sample nonparametric tests were developed for this study. Monte Carlo study showed that these tests performed well even when the sample size was moderately large. A real data set was used to show that the new methodologies provide a good method for assessing the potential risks of pesticides residues at an investigated site.
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Whittle, Don. "Stream mesocosms in ecological risk assessment : experimental, analytical and ecological considerations." Thesis, University of Sheffield, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.339940.
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Hayes, Keith Robert. "Quantitive ecological risk assessment a ballast-water case study." Thesis, Heriot-Watt University, 2000. http://hdl.handle.net/10399/1230.
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d'Errico, Giuseppe. "Multidisciplinary approach for Ecological Risk Assessment (ERA): practical models." Doctoral thesis, Università Politecnica delle Marche, 2016. http://hdl.handle.net/11566/242992.
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L’Analisi di Rischio Ecologico (Ecological Risk Assessment; ERA) è una procedura gerarchica, a più livelli di approfondimento per la caratterizzazione della qualità ambientale e del rischio associato. L’approccio multidisciplinare Weight Of Evidence (WOE) è una componente essenziale in questi processi per valutare e classificare lo stato ecologico degli ambienti acquatici, integrando risultati derivanti da tipologie d’indagine diverse (linee di evidenza, LOEs), per una valutazione sia quantitativa che qualitativa del Rischio Ecologico. Secondo la struttura generale di questa metodologia, è stato sviluppato un modello sia concettuale che informatico (Sediqualsoft) che elabora ed integra i risultati di molteplici linee di evidenza, dando loro un peso diverso in funzione della loro rilevanza ai fini dell’indagine.
Obiettivi specifici di questo dottorato sono stati: (I) l’implementazione del processo ERA con lo sviluppo di criteri concettuali e algoritmi matematici per l’elaborazione di una LOE per le comunità bentoniche; (II) lo sviluppo di un nuovo modello WOE per la valutazione di qualità in ambienti d'acqua dolce; (III) lo sviluppo di un nuovo strumento per la caratterizzazione e la gestione dei materiali da dragare in aree portuali; (IV) la validazione dei diversi modelli in casi pratici. L'obiettivo finale è stato quello di sviluppare un approccio scientificamente valido, supportato da un’architettura informatica, utile come strumento operativo per le Istituzioni pubbliche, enti privati, decisori politici o gestori ambientali all'interno di una procedura ERA.
Questa tesi di dottorato ha confermato l'importanza dell’approccio WOE all'interno delle procedure ERA, dimostrando che i modelli sviluppati sono stati utili per elaborare grandi quantità di dati eterogenei ottenuti da diverse tipologie d’indagine, riassumendo informazioni complesse in un formato “user-friendly” per un processo più ampio di valutazione del rischio, favorendo infine le decisioni gestionali.Ecological Risk Assessment (ERA) is a hierarchical procedure to characterize environmental quality and associated risks. The multidisciplinary Weight Of Evidence (WOE) approach is an essential component in this process to integrate various elements of quality (Lines Of Evidence, LOEs), using methods that are either qualitative or quantitative. According to the general structure of this methodology, a conceptual and software-assisted model (Sediqualsoft model) has been developed to elaborate and differently weight heterogeneous data from various typologies of chemical and biological investigations. The general purpose of this PhD study was to provide a further contribution to the integrated and multidisciplinary assessment of environmental quality. In particular, specific aims were (i) implementation of the ERA process with the development of criteria and mathematical algorithms for a specific LOE on benthic communities; (ii) development of a new WOE model (conceptual and informatic) for quality assessment in freshwater environments; (iii) development of a new tool derived from the WOE model and specifically adapted toward Normative Guidelines for characterization and management options of dredged materials in harbor areas; (iv) validation of these models in field studies. The final objective was the development of a scientifically-sound approach, supported by an informatic architecture, useful as operational tool for Public Institutions, private entities, political decisors or environmental managers within the complexity of ERA procedure. In conclusion, this PhD Thesis corroborated the importance of multidisciplinary WOE approaches for characterizing environmental quality within an ERA procedure. The results of this thesis demonstrated that the developed WOE models were useful to elaborate large datasets of different typologies of data, summarizing complex information in a user-friendly format for a comprehensive process of “site-oriented” management decisions.
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DUARTE, Heitor de Oliveira. "A methodology for quantitative ecological risk assessment for industrial accidents." Universidade Federal de Pernambuco, 2011. https://repositorio.ufpe.br/handle/123456789/5960.
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Previous issue date: 2011Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Recentes acidentes industriais, como vazamentos tóxicos, têm causado danos catastróficos ao meio ecológico (i.e. plantas e animais), de modo que um método efetivo para analisar riscos ecológicos tem sido demandado. Em primeiro lugar, este trabalho tem como objetivo propor uma metodologia capaz de quantificar riscos ecológicos inerentes a eventos raros como acidentes industriais. Utiliza-se a modelagem populacional para simular futuras mudanças na abundância populacional de espécies-chave em risco e, assim, estimar a probabilidade de extinção ou declínio, tempo para extinção e outras medidas, para cada cenário acidental. Assim, foi possível desenvolver uma abordagem que combina os danos ecológicos (previstos através da modelagem populacional) com a frequência de ocorrência do cenário acidental (estimada através de dados históricos e análise de confiabilidade). O resultado é uma curva de risco FN (similar ao resultado de uma análise de risco a humanos), onde N é o declínio populacional médio e F a frequência acumulada de acidentes com declínio maior ou igual a N. Em segundo lugar, o trabalho apresenta uma aplicação da metodologia para quantificar os riscos ecológicos provenientes de acidentes associados ao transporte e manuseio de petróleo que abastece uma refinaria no Complexo Industrial Portuário de Suape-PE, no Nordeste do Brasil. Esta instalação está localizada próxima a um rico ecossistema aquático de alta biodiversidade. A população de uma espécie nativa foi estrategicamente escolhida para representar o ecossistema, alguns cenários de derramamento de petróleo foram simulados e suas frequências de ocorrência estimadas. Para cada cenário acidental, a concentração de óleo que atinge a população foi prevista via modelagem de destino e transporte. Os riscos ecológicos foram quantificados e apresentados em uma curva FN. Uma análise de sensibilidade foi feita para explorar como mudanças em parâmetros específicos causam mudanças nas medidas de risco. Além disso, a incerteza foi medida como um intervalo (limite superior e inferior) para as medidas de riscos com base em cenários pessimistas e otimistas. Finalmente, a metodologia mostrou-se viável, eficiente, conveniente e flexível, apesar de que algumas melhorias ainda podem ser feitas e estas foram propostas para trabalhos futuros
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Ip, Tsz-kin Derek. "Ecological risk assessments for marine mammals in Hong Kong." View the Table of Contents & Abstract, 2006. http://sunzi.lib.hku.hk/hkuto/record/B37120694.
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Oliveira, Paulo Alexandre da Silva. "Ecological risk assessment of pesticides in maize and tomato crops." Master's thesis, ISA/UL, 2017. http://hdl.handle.net/10400.5/17946.
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Mestrado em Engenharia Agronómica - Proteção das plantas - Instituto Superior de AgronomiaFoi realizado um estudo das comunidades de zooplâncton presentes na água de irrigação das culturas de milho e tomate em condições mediterrâneas portuguesas, a fim de vincular possíveis relações entre a exposição a pesticidas e as respostas biológicas. Este trabalho é uma contribuição para melhorar a relevância ecológica da Avaliação do Risco Ambiental de Pesticidas. Um total de 37 espécies de rotiferos e 2 famílias de cladóceros foram identificadas. Os principais componentes do zooplâncton em todos os locais de amostragem foram nauplios e rotíferos que parecem ser menos afetados pelos pesticidas. A concentração de 12 ug / l de clorpirifos reduz o número de macrozooplâncton, permitindo o aumento das densidades de rotiferos. Valores de 3,5-4,7 ug / l de clorantrinaprole e 0,96 ug / l de metribuzina parecem afetar negativamente o tamanho da comunidade de copépodos. As comunidades de Cladóceros e Ostracodes parecem diminuir quando os valores do glifosato estão na faixa de 2,3-3,9 ug / l. Os valores de glifosato (0,66 ug / l), Ampa (0,88 ug / l) e Fosfato (2,38 mg / l) parecem estar ligados a valores mais baixos de índice de riqueza de espécies
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Ip, Tsz-kin Derek, and 葉子健. "Ecological risk assessments for marine mammals in Hong Kong." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B39849132.
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Silva, Emília Cardoso Moura da. "Approaches to improve the ecological risk assessment of pesticides in freshwaters." Doctoral thesis, ISA/UL, 2015. http://hdl.handle.net/10400.5/9255.
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Doutoramento em Engenharia Agronómica - Instituto Superior de AgronomiaOne of the most important ways of improving agricultural production is the use of plant protection products. As this type of pesticides is used within the catchment area of freshwaters there is a potential for side-effects to occur in aquatic ecosystems. New challenges for risk assessment were addressed to achieve good chemical and ecological status in European water bodies. Site-specific and ecologically-based approaches were developed and applied to three important Portuguese river basins. Better criteria for the assessment of the ecological and chemical status of water bodies was provided by calculating groundwater threshold values for pesticides and by focusing on river basin specific pollutants. A list of priority pesticide mixtures that might pose aquatic risks was obtained by employing risk quotients based on concentration addition as a ‘screening level’ risk assessment of pesticide mixtures, and the multi-substance potentially affected fraction, representing a higher tier, with more practical usefulness and relevancy for risk management. For an integrated assessment of pesticide stress in freshwaters, and moving toward a more holistic approach, chemical analysis were used in combination with effect-based tools, in order to provide a link between chemical and ecological assessments. The results contribute for reducing the risks of pesticides in freshwaters
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Su, Yang. "Development of an Ecological Risk Assessment Tool for Trace Organic Compounds." University of Cincinnati / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1428653300.
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Negreiros, Gustavo Hees de. "Understanding and modeling ecological processes controlling flammability in seasonally dry evergreen forests of the Brazillian Amazon /." Thesis, Connect to this title online; UW restricted, 2004. http://hdl.handle.net/1773/5528.
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Ward, Daniel John. "An ecological assessment of secondary poisoning risk in the Australian sugarcane industry." Thesis, Queensland University of Technology, 2008. https://eprints.qut.edu.au/31325/1/Daniel_Ward_Thesis.pdf.
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Rodenticide use in agriculture can lead to the secondary poisoning of avian predators. Currently the Australian sugarcane industry has two rodenticides, Racumin® and Rattoff®, available for in-crop use but, like many agricultural industries, it lacks an ecologically-based method of determining the potential secondary poisoning risk the use of these rodenticides poses to avian predators. The material presented in this thesis addresses this by: a. determining where predator/prey interactions take place in sugar producing districts; b. quantifying the amount of rodenticide available to avian predators and the probability of encounter; and c. developing a stochastic model that allows secondary poisoning risk under various rodenticide application scenarios to be investigated. Results demonstrate that predator/prey interactions are highly constrained by environmental structure. Rodents used crops that provided high levels of canopy cover and therefore predator protection and poorly utilised open canopy areas. In contrast, raptors over-utilised areas with low canopy cover and low rodent densities, but which provided high accessibility to prey. Given this pattern of habitat use, and that industry baiting protocols preclude rodenticide application in open canopy crops, these results indicate that secondary poisoning can only occur if poisoned rodents leave closed canopy crops and become available for predation in open canopy areas. Results further demonstrate that after in-crop rodenticide application, only a small proportion of rodents available in open areas are poisoned and that these rodents carry low levels of toxicant. Coupled with the low level of rodenticide use in the sugar industry, the high toxic threshold raptors have to these toxicants and the low probability of encountering poisoned rodents, results indicate that the risk of secondary poisoning events occurring is minimal. A stochastic model was developed to investigate the effect of manipulating factors that might influence secondary poisoning hazard in a sugarcane agro-ecosystem. These simulations further suggest that in all but extreme scenarios, the risk of secondary poisoning is also minimal. Collectively, these studies demonstrate that secondary poisoning of avian predators associated with the use of the currently available rodenticides in Australian sugar producing districts is minimal. Further, the ecologically-based method of assessing secondary poisoning risk developed in this thesis has broader applications in other agricultural systems where rodenticide use may pose risks to avian predators.
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IPPOLITO, ALESSIO. "Plant protection product risk assessment for aquatic ecosystems: evaluation of effects in natural communities." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2012. http://hdl.handle.net/10281/30471.
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The level of alteration in response to the same level of exposure can vary greatly among different ecosystems: in particular, effects provoked by chemicals are not only relying on their “absolute toxicity” and on their concentration, but also on the ecological vulnerability of the system. Vulnerability is often overlooked in current risk assessment procedure, but its knowledge is pivotal in site-specific studies, where the object of the protection is shifted from a generic scenario to a real ecological system. The study of ecological vulnerability confirms that risk assessment, as becoming site-specific, needs more ecological knowledge. In this path, the use of ecological and biological traits of organisms has proven to be a promising approach to evaluate the ecological vulnerability at different level of biological organization.
In this work the issue of the ecological vulnerability has been considered from several different perspectives, using multiples methodologies and working at completely different scales. The leading thread is to show how an ecologically based approach can enhance our understanding of environmental processes and thus improving risk assessment methodologies.
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DUARTE, Heitor de Oliveira. "A novel quantitative ecological and microbial risk assessment methodology: theory and applications." Universidade Federal de Pernambuco, 2016. https://repositorio.ufpe.br/handle/123456789/17633.
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The environment is a complex system where human, ecological environment (e.g., plants, animals, microbes), materials (eg, pollutants, medical), and meteorological/oceanographic conditions interact. The human impact has potential to cause significant damage to the ecological environment (e.g., potential oil spills on the coast cause risk to coastal ecosystems, tuna industrial fishing cause risk to sharks that are bycaught). Similarly, the human impact may turn against the human itself by favoring the growth of populations of unwanted species (e.g., poor sanitation favors the growth of microbial populations that cause risk of an excessive proportion of sick humans). Therefore, it has been demanded an efficient method of quantifying the risks in systems where plant, animals or microbes populations are involved in order to give support to risk management in environmental issues, fisheries management and public health. First, this paper proposes a methodology capable of quantifying ecological risks (i.e., likelihood of adverse effects on the ecosystem, in the long term, due to exposure to stressors such as chemical, fishing, etc.) or microbial risks (i.e., likelihood of adverse effects in humans, in the long term, due to exposure to microbial pathogens). It uses population modeling to simulate future changes in populations of ecologically important species (e.g., fish, corals, sharks), or undesirable (e.g., parasites), under conditional scenarios simulating the influence humans impacting and/or managing the risks. The risk is calculated in terms of probability of extinction or decline, explosion or growth of these populations over time. Second, the methodology is applied to four case studies in Brazil. Each of them have their specific conclusions, as follows. (1) Ecological Risk Assessment caused by potential maritime accidents in the transportation of oil to the port of Suape. Conclusion: low but significant ecological risk. (2) Ecological Risk Assessment caused by potential maritime accidents in the passage of oil tankers nearby Fernando de Noronha. Conclusion: negligible ecological risk, although a more detailed analysis is required due to limited data. (3) Microbial Risk Assessment to Porto de Galinhas community inherent to sanitation and medical treatment program. Conclusion: high microbial risk, the current sanitation level is not enough to contain the spread of schistosomiasis disease, and periodic treatment of patients is not efficient to reduce risks significantly. (4) Ecological Risk Assessment of tuna industrial fishing in Brazilian waters. Conclusion: industrial tuna fishing does not cause significant risks to the population of Mako sharks in the South Atlantic Ocean. In each case study, several conditional scenarios were simulated for the next 100 years, including adverse scenarios and scenarios with risk control measures. Thus, it was possible to quantify the added risk caused by each adverse condition as well as the reduced risk caused by each control measure. In this way, the manager has objective information to prioritize scenarios and evaluate the cost-effectiveness of control measures. The general conclusion of this work is that the proposed methodology has proven to be practicable, useful and efficient.
O meio-ambiente é um sistema complexo onde interagem humanos, meio ecológico (e.g., plantas, animais, micróbios), materiais (e.g., poluentes, medicinais) e condições meteorológicas/oceanográficas. O impacto humano tem potencial para causar danos significativos ao meio ecológico (e.g., potenciais vazamentos de petróleo na costa causam risco ao ecossistema costeiro, pesca industrial de atum causa risco aos tubarões que são pescados por acidente). Similarmente, o impacto humano pode se voltar contra o próprio humano ao favorecer o crescimento de populações de espécies indesejáveis (e.g., saneamento básico precário favorece o crescimento de populações de micróbios que causam risco de haver uma excessiva parcela de humanos doentes). Portanto, tem sido demandado um método eficiente de quantificar os riscos inerentes a sistemas onde populações de plantas, animais ou micróbios estejam envolvidas, de forma a dar suporte para o gerenciamento dos riscos em problemas de gestão ambiental, gestão pesqueira e saúde pública. Em primeiro lugar, este trabalho propõe uma metodologia capaz de quantificar riscos ecológicos (i.e., probabilidade de ocorrência de efeitos adversos no ecossistema, no longo prazo, devido à exposição a estressores como químicos, pesca, entre outros) ou microbianos (i.e., probabilidade de ocorrência de efeitos adversos em humanos, no longo prazo, devido à exposição a patógenos microbianos). Utilizase a modelagem populacional para simular futuras mudanças nas populações de espécies ecologicamente importantes (e.g., peixes, corais), ou indesejáveis (e.g., parasitas), quando condicionadas a cenários que simulam a influência do humano causando impacto e/ou gerindo os riscos. O risco é calculado em termos de probabilidade de extinção ou declínio, explosão ou crescimento, dessas populações ao longo do tempo. Em segundo lugar, aplica-se a metodologia para avaliar o risco inerente a quatro estudos de caso no Brasil. Cada um deles tem sua conclusão específica, como segue. (1) Análise de Risco Ecológico causado por potenciais acidentes marítimos no transporte de petróleo para o porto de Suape. Conclusão: baixo risco ecológico, porém significativo. (2) Análise de Risco Ecológico causado por potenciais acidentes marítimos na passagem de navios petroleiros ao largo de Fernando de Noronha. Conclusão: risco ecológico negligenciável, mas uma análise mais detalhada é necessária devido à escassez de dados. (3) Análise de Risco Microbiano à comunidade de Porto de Galinhas inerentes ao sistema de saneamento básico e programa de tratamento medicinal. Conclusão: alto risco microbiano, o nível de saneamento básico atual não é suficiente para conter a proliferação da doença esquistossomose, e o tratamento periódico de doentes não é eficiente para reduzir os riscos significativamente. (4) Análise de Risco Ecológico causado pela pesca industrial de atum em águas brasileiras. Conclusão: a pesca industrial de atuns não causa riscos significativos à população de tubarões Mako no oceano Atlântico Sul. Em cada estudo de caso, foram simulados diversos cenários condicionais para os próximos 100 anos, incluindo cenários adversos e cenários com medidas de controle dos riscos. Assim, foi possível quantificar a adição do risco causada por cada cenário adverso e a redução do risco causada por cada medida de controle. Desta forma, o gestor tem informação objetiva para priorizar cenários e avaliar o custo-benefício das medidas de controle. A principal conclusão deste trabalho é que a metodologia proposta provou-se ser praticável, útil e eficiente.
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Sinnett, Danielle. "Application of ecological risk assessment to community greenspace establishment on contaminated land." Thesis, University of Reading, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.525132.
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Sanchez, André Luís. "Ecological risk assessment in pesticide contamination scenarios: from individuals to ecosystems responses." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/18/18139/tde-06102016-101708/.
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Ecological risk assessment (ERA) studies are important to assess environmental changes that have been caused by anthropogenic activities. These integration models show the estimation of adverse risk effects across the levels of biological organization potentially exposed to perturbation, including a better understanding of the ecosystems complexity. It is well known that the pesticide have severe environment effects contributing to biodiversity loss and trophic levels changes. In this context, the aim of this study was to evaluate the ecological risk assessment in pesticide contamination scenarios for aquatic and terrestrial compartments. To attempt it direct and indirect effects on individual response for different biological organization and for multi trophic interactions responses with ecosystems models were evaluated. Thus the environmental impacts in relation to losses and changes of the ecosystems functions and services were analyzed. For this purpose, a risk scenario was designed to compare the Ivermectin contamination exposure routes, via dermal (soil) and oral (food) on Eisenia fetida reproduction tests. An experimental approach was constructed to characterise the effects of the fungicide Scala® (Pyrimethanil) in spraying application comparing to homogenous soil application on a constructed soil multi-species test system. n experiment was performed to reported the effects of the fungicide Mythos® (Pyrimethanil) with terrestrial plant test followed by elutriate test with non-targets freshwater organisms and avoidance test with soil invertebrates and quantify the ecosystems services framework. A holistic higher tier fungicide risk assessment was done with terrestrial and aquatic responses and trophic levels with multitrophic interactions in ecosystem models and supplementary with individuals\' responses. The results obtained suggest that the analyzed reproduction parameters for earthworms were affected with the increase of ivermectin concentrations with statistical significant differences between the contamination exposure routes. The fungicide pyrimethanil has adverse effect on soil invertebrates\' response for the application and spatial distribution with the habitat preferences and foraging abilities has affected directly or indirectly by the fungicide toxicity. The impacts by the runoff and leaching pesticides into adjacent water bodies and surrounding soil showed changes in the organism\'s structure with changes and loss in the provisioning, regulatory and supporting services. The integrated holistic four-tiered fungicide risk assessment showed the possible impacts and the adverse effects on the terrestrial and aquatic organisms, ecosystems and processes in the simulate scenarios. From the results, it is possible to conclude that the experiments performed crossed the multiple aspects of contaminations and show the individuals to ecosystems responses approaches using the exposure routes of contamination, multi trophic interactions of experimental ecosystems models, behavioral, individual and some comparatives responses with aquatic and terrestrial compartments in risk assessment. Furthermore, this study are an important register for the deleterious effects and responses to impacts of pesticides, prompting the possible environmental losses and changes of the ecosystems functions and services in disturbances areas.Os estudos de avaliação de risco ecológico consistem em avaliar os riscos ecológicos ocasionados pelas diversas atividades antropogênicas a um determinado sistema. Essa abordagem de integração reporta a estimativa dos efeitos de risco adverso através dos níveis de organização biológica potencialmente expostos a pertubação, incluindo assim uma melhor compreensão da complexidade dos ecossistemas. É bem conhecido que os pesticidas possuem efeitos nocivos ao meio ambiente, contribuindo para a perda de biodiversidade e mudanças nos níveis tróficos. A partir dessa análise, o objetivo geral desse estudo foi uma avaliação de risco ecológico em cenários de contaminação por pesticidas em relação aos compartimentos terrestres e aquáticos. Para tanto, foram avaliados os efeitos diretos e indiretos sobre as respostas individuais para diferentes níveis de organização biológica e para as interações multitróficas através de modelos ecossistêmicos. Assim, foram analisados os impactos ambientais em relação as perdas e mudanças das funções e serviços dos ecossistemas. Para esse propósito, foram desenvolvidos cenários de risco em relação as rotas de exposição do antiparasitário Ivermectin para a minhoca Eisenia fetida em relação a testes de reprodução, através da via dermal (solo) e oral (comida). Foi construída uma abordagem experimental para caracterizar os efeitos do fungicida Scala® (Pyrimethanil), comparando a aplicação através de pulverização por spray com a aplicação homogênea no solo em um sistema terrestre multiespécies. Experimentos foram realizados para reportar os efeitos do fungicida Mythos® (Pyrimethanil) em plantas terrestres alvo, seguidos por teste com elutriato com organismos de água doce não-alvo e testes de fuga com invertebrados terrestres não-alvo e uma quantificação dos serviços ecossistêmicos. Foi realizada uma avaliação de risco holística do fungicida pyrimethanil com respostas dos organismos terrestres e aquáticos e das interações tróficas através dos modelos ecossistêmicos e complementados com respostas individuais. Os resultados obtidos sugerem que os parâmetros de reprodução para as minhocas foram afetados com o aumento das concentrações de ivermectina com diferenças estatísticas significativas entre as rotas de exposição a contaminação. O fungicida pyrimethanil mostrou efeitos adversos sobre os invertebrados terrestres para as aplicações do pesticida e para a distribuição espacial, sendo as preferências de habitat e habilidade de forageio direta ou indiretamente afetadas pela toxicidade do fungicida. Os possíveis impactos do runoff e lixiviação nos corpos de água e solos adjacentes mostram mudanças na estrutura da comunidade com mudanças e perdas nos serviços ecossistêmicos de provisão, regulação e suporte. A avaliação de risco holística mostrou os impactos e efeitos adversos sobre os organismos terrestres e aquáticos, ecossistemas e processos nos diferentes cenários de simulação. Ao analisar os dados obtidos é possível concluir que os experimentos realizados permeiam os múltiplos aspectos da contaminação por pesticidas, mostrando respostas de indivíduos a ecossistemas através das rotas de exposição da contaminação, interações multitróficas a partir dos experimentos de modelos ecossistêmicos, respostas individuais, comportamentais e comparativas com os sistemas terrestres e aquáticos em avaliações de risco ecológico. Portanto, esse estudo se apresenta como um importante registro dos efeitos deletérios e das respostas dos impactos por pesticidas, levando a possíveis perdas e mudanças das funções e serviços ecossistêmicos em áreas com distúrbios.
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Leitão, Sara Pais de Almeida da Silva. "New improvements on pesticide ecological risk assessment on the soil-water interface." Doctoral thesis, ISA, 2013. http://hdl.handle.net/10400.5/6449.
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Doutoramento em Engenharia Agronómica - Instituto Superior de AgronomiaImproving knowledge to evaluate and reduce pesticide impacts in the environment is a present concern to achieve their sustainable use. With the aim of increasing ecological relevance on the environmental risk assessment of pesticides (ERA), an integrated approach was undertaken linking pesticide fate and effects on aquatic and terrestrial non-target organisms under irrigated crop-based scenarios in Mediterranean realistic conditions, for which there is a lack of studies. Pesticides fate and effects were assessed by adopting an innovative approach embracing different levels of ERA complexity: a refined first-tier with the use of natural soil in ecotoxicological testing, instead of the conventional artificial soil; a refined higher-tier level performing simulations of cropbased agricultural scenarios of maize, potato and onion crops, with the application of the fungicides azoxystrobin and chlorothalonil and the insecticide ethoprophos, using a new semi-field methodology; and an higher tier field study incorporating biological interactions and dynamics of soil fauna communities and environmental factors that determine the effects of pesticides in the field under realistic agricultural practices. This study will increase the knowledge on ecological risks of pesticides under field situations improving decision making towards a sustainable use of pesticides and ecological protection
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Arumugam, Anandkumar. "Ecological risk assessment of the Miri coast, Sarawak, Borneo: A biogeochemical approach." Thesis, Curtin University, 2016. http://hdl.handle.net/20.500.11937/698.
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Ecological risk assessment was made along the Miri coast based on trace element concentrations (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Rb, Zn) in the seawater, sediments, and aquatic biota (fish, shrimp, crabs, and bivalves). Prevailing major geochemical processes were identified. Contamination and risk assessment indices were estimated. Sediments were contaminated by Cu and Zn, but in the marine life the remaining metals were within the permissible limits set by international and national guidelines.
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JIANG, HUAN. "Ecological Risk Assessment of Salts in Swedish Freshwater Ecosystem : A preliminary assessment for invertebrates and vertebrates." Thesis, Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-16578.
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Pham, Vivian G. "Ecological Risk Assessment of Heavy Metal Content in the Hatillo River, Costa Rica." Scholarship @ Claremont, 2015. http://scholarship.claremont.edu/scripps_theses/571.
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Rivers all around the world have become increasingly polluted with heavy metals, largely due to industrialization and urbanization. Organisms exposed to high concentrations of heavy metals have shown evidence of biotoxicity and physical deformities. With biomagnification in mind, the possibility that this contamination may soon directly affect humans is a real concern, and policies in manufacturing industries worldwide may have to be reformed. In this study, we measured the concentrations of arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni), and lead (Pb) in the Hatillo River and compared these values to those measured in the Tarcoles River, a highly polluted river, and Terciopelo Creek, a relatively clean river. The results showed that the Hatillo River had significantly lower levels of most detected heavy metals than both the Tarcoles and Terciopelo. Overall, sediments in all rivers showed high levels of heavy metal content--especially in chromium, copper, nickel, and lead--which could build up and affect organisms over a long period of time.
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Takacs, P. "Evaluation of probabilistic ecological risk assessment methodology using aquatic microcosms and azinphos-methyl." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0002/MQ43226.pdf.
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Sorenson, Mary T. "Deterministic vs probabilistic ecological risk assessment modeling at hazardous waste sites : a comparative case study." Thesis, Georgia Institute of Technology, 2000. http://hdl.handle.net/1853/25303.
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Gerber, Liezel. "Biodiversity risk assessment of South Africa’s municipalities." Thesis, Stellenbosch : University of Stellenbosch, 2005. http://hdl.handle.net/10019.1/1614.
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Thesis (MSc (Botany and Zoology))--University of Stellenbosch, 2005.South Africa is one of the most biodiverse countries in the world and even with conservation initiatives in place continues to face biodiversity loss. There is a need to prioritise areas for conservation as resources for conservation purposes are limited in South Africa. From prioritisation methods reviewed it was found that prioritisation indices normally use one or a combination of variables that measure stock; and/or variables that measure threat.
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Säterberg, Torbjörn. "Minimum Ecologically Viable Populations : Risk assessment from a multispecies perspective." Thesis, Linköping University, Department of Physics, Chemistry and Biology, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-18959.
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The extinction risk of threatened species has traditionally been assessed by the use of tools of Population Viability Analysis (PVA). Species interactions, however, have seldom been accounted for in PVA:s. The omission of species interactions in risk assessments may further lead to serious mistakes when setting target sizes of populations. Even a slight abundance decrease of a target species may result in changes of the community structure; in the worst case leading to a highly impoverished community. Of critical importance to conservation is therefore the question of how many individuals of a certain population that is needed in order to avoid this kind of consequences. In the current study, a stochastic multispecies model is used to estimate minimum ecological viable populations (MEVP); earlier defined as “the minimum size of a population that can survive before itself or some other species in the community becomes extinct”. The MEVP:s are compared to population sizes given by a single species model where interactions with other species are treated as a constant source incorporated in the species specific growth rate. MEVP:s are found to be larger than the population sizes given by the single species model. The results are trophic level dependent and multispecies approaches are suggested to be of major importance when setting target levels for species at the basal level. Species at higher trophic levels, however, are altogether more prone to extinction than species at the basal level, irrespective of food web size and food web complexity.
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Rose, Robyn Ilene. "An ecological risk assessment of BT transgenic sweet corn on non-target arthropod communities." College Park, Md. : University of Maryland, 2005. http://hdl.handle.net/1903/2451.
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Thesis (Ph. D.) -- University of Maryland, College Park, 2005.Thesis research directed by: Entomology. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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Mellet, Bernice. "Ecological risk assessment of fisheries on sea turtles in the South Western Indian Ocean." Thesis, Nelson Mandela Metropolitan University, 2015. http://hdl.handle.net/10948/9957.
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The SWIO is an area of great biodiversity and included in the diverse species that occupy the region are five species of sea turtles that include green turtles, hawksbills, leatherbacks, loggerheads and olive ridleys. Despite considerable conservation efforts at sea turtle rookeries in the South Western Indian Ocean, only green and loggerhead turtle populations have shown an increase in population size in recent years (<10 years), whereas leatherbacks remained stable and hawksbills and olive ridleys declined. This begs the question if fisheries (or other offshore pressures) are responsible for slowing the recovery of these populations in the region, and if so, which specific fisheries are responsible for this trend? Several offshore (mostly industrial) and coastal (mostly artisanal) fisheries overlap with sea turtle distribution at sea. Industrial fisheries that are globally known to have a demonstrable impact on sea turtle populations are longline and to a lesser extent purse seine fisheries, whilst prawn trawl, gillnet and beach seine fisheries are coastal fisheries with a known negative impact on sea turtle populations. Holistic conservation strategies should be developed that include both land and sea protection for sea turtle species. It is thus necessary to identify and manage offshore threats including fisheries activities, particularly those fisheries that are showing the highest risk to sea turtle populations. This prompted an investigation into the bycatch rates and mortality of all sea turtle species that occur in the SWIO region in several offshore and coastal fisheries including both industrial (longline, purse seine and prawn trawl) and artisanal (including gillnet and beach seine) fisheries. The specific aims were (i) to identify and quantify the interactions (and if possible mortality) of sea turtle species in fisheries and (ii) to identify vulnerable species/populations to fishing operations using a semi-quantitative Ecological Risk Assessment (ERA) in the form of a Productivity-Susceptibility Analysis (PSA). Published information, online databases and technical reports were used as data sources to establish a database containing essential information regarding fishing effort and sea turtle bycatch in the region. The existing information was used to map fisheries extent and effort within the region, and to perform bycatch calculations. Interactions and mortality rates for sea turtles in five fisheries were quantified using bycatch rates from regional studies. Between 2000 – 2011, industrial longline and purse seine fisheries captured sea turtles at a rate of 4 388 indiv.y-1, with the mortality rate being 189 indiv.y-1. The bulk of these interactions were in the longline industry that captured 4 129 ± 1 376 indiv.y-1, with a corresponding mortality rate of 167 ± 53 indiv.y-1. The most commonly caught species (in longlines) were loggerheads and leatherback turtles, but the greatest impact is expected to be on the leatherback population due to the high interaction rate relative to population size. The bycatch (259 ± 34 indiv.y-1) and mortality (20 ± 2 indiv.y-1) rates of sea turtles in the purse seine fishery was considerably lower than the longline fishery. The purse seine fishery thus does not seem to have a significant impact on sea turtle populations in the SWIO. The impact of all forms of fish aggregation devices were excluded from the analysis as the impacts of these are poorly documented. Coastal prawn trawl, gillnet and beach seine fisheries captured an estimate of between 50 164 - 52 370 indiv.y-1 from 2000-2011. The highest bycatch rate was estimated for gillnet fisheries (40 264 indiv.y-1) followed by beach seine fisheries (9 171 indiv.y-1) and prawn trawl fisheries (at 1089 – 2795 indiv.y-1). The gillnet fishery could be responsible for slowing the recovery rate of green turtle and leatherback populations in the SWIO due to the high capture rates in this fishery compared to the population sizes of the species. Beach seine and prawn trawl fisheries are not expected to be hamper the recovery rate of any of the populations in the SWIO due to the low levels of interactions and low mortality rates compared to the population sizes. There are however very few data available regarding the bycatch of sea turtle species within these fisheries, highlighting the need for further research regarding this. A productivity-Susceptibility Analysis (PSA) was used to evaluate the relative vulnerability of species to fisheries, and is frequently applied in data poor situations. Limited data on sea turtle life history characteristics and population dynamics of species in the SWIO prompted the use of a PSA to determine the species most vulnerable to fisheries in the region. Results of the PSA indicated that gillnet fisheries poses the largest fishery-related threat to sea turtle populations, specifically the green and leatherback populations. The longline fishery that poses a particular threat to the leatherback population in the SWIO is also a particular concern. A cumulative impact assessment (combining fisheries and other threats) indicated that the SWIO leatherback population is extremely vulnerable to the combination of threats that influence this population in the SWIO. Even though individual fisheries may pose a small threat, the cumulative impacts of the fisheries can lead to severe impacts on populations such as slowing the recovery rate of populations. There are however significant data gaps that require attention in order to fully assess the impact of these fisheries on sea turtle populations. Despite the fact that fisheries are not implicated as a mayor reason for the decline in the hawksbill and olive ridley populations in the region, these two species are in decline indicating that there are other factors responsible for the decline not yet identified. It however remains imperative to reduce the mortality from all sources to ensure the continued viability of sea turtle populations in the region.
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Claassen, Marius. "The development and application of ecological risk assessment in South African water resource management." Thesis, Rhodes University, 2006. http://hdl.handle.net/10962/d1006177.
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The provision of goods and services by aquatic ecosystems plays an important role in socio-economic development and livelihoods in the southern African region. Water resource management in South Africa developed from an agrarian and pastoral focus up to 1956 to also supporting mining and industrial activities. This led to the introduction of the resource water quality objectives and pollution prevention approaches, which balanced the needs for development and protection. Prior to 1994, access to water resources was limited to riparian property owners and a minority of the population who controlled industrial and mining activities. The establishment of a democratic government amplified the need for accelerated socio-economic development, with equity, efficiency and sustainability being the principles of such development. New approaches were needed, which could achieve these development objectives and secure the resource base for future generations. An overview of the scientific process highlighted a risk based approach as potentially supporting the much needed balance between development and protection. The aims of this thesis is to develop a framework and process for the application of ecological risk assessment to water resource management in South Africa, to use case studies to draft guidelines for ecological risk assessment and to assess the degree to which ecological risk assessment can contribute to effective water resource management in South Africa. The United States Environmental Protection Agency’s guidelines for ecological risk assessment were identified amongst international best practice as meeting the requirements for local application. A framework was drafted for ecological risk assessment in South Africa, with the main phases being to agree on objectives, formulate the analysis plan, analyse information, characterise risk and manage risk. Modifications from the Environmental Protection Agency’s process include the order of activities in the first phase, the explicit testing of hypotheses and clarification of the evaluation of existing data or collection of new data. An industrial effluent case study was used to assess the applicability of the proposed framework. The case study dealt specifically with the assessment of risks posed by current conditions and long term licence conditions. The framework was found to be useful to identify weaknesses in the established monitoring programme and to evaluate lines of evidence to assess the degree to which the stated conditions would have unacceptable consequences. The study highlighted several weaknesses in the suggested framework, of which the most critical is the interpretation of the risk hypothesis as a testable null hypothesis. It became clear that cause-effect relationships should be stated as the risk hypothesis, whereas the assessment should evaluate expressed or expected conditions against a risk profile for a given stressor to benefit fully from the risk assessment approach. Changes to the framework terminology were suggested as well as nested feedback loops to allow for iterative processes where new information becomes available. The proposed guidelines incorporate the learning from the case study application as well as feedback from a peer review process. The guidelines incorporate the suggested actions under each phase as well as notes providing the rationale for each step. Three case study outlines were provided to assist users with the interpretation of the guidelines in different applications. The proposed guidelines are applied in an ecological Reserve determination case study, which specified the ecological water quality requirements. The study found that a risk-based approach was followed in the development of the water resource management policy, but the Reserve determination method is generally hazard based, with site specific modifications of the target values being allowed on a conservative basis. The case study highlighted a lack of readiness of water resource managers to accommodate scientific results expressed as probability distributions in support of management decisions. The thesis is concluded with a discussion of the key learning points of the ecological risk assessment development process. The evaluation highlights the move from stating and testing a null hypothesis to stating the risk hypothesis and evaluating the stated conditions against a risk profile. Several implementation challenges are highlighted, with specific recommendations made for adopting the proposed guidelines.
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Kapo, Katherine E. "Eco-Epidemiological Analysis for Screening-Level Ecological Risk Assessment: A Geographic Information Systems Approach." Wright State University / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=wright1246903901.
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Duodu, Godfred Odame. "Characterisation, source apportionment and ecological risk assessment of some pollutants in Brisbane river sediment." Thesis, Queensland University of Technology, 2017. https://eprints.qut.edu.au/103672/1/Godfred%20Odame_Duodu_Thesis.pdf.
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This thesis presents the first simultaneous analysis of heavy metals and organic residues in Brisbane River sediment after the 2011 and 2013 floods. New methods for rapid analysis of elements in sediment and assessment of ecological risk were developed. The thesis provides crucial information regarding levels, distribution, sources and ecological risks of the pollutants in the sediment. This will assist in risk management and formulation of effective pollution mitigation. The generic outcomes of this thesis are expected to provide essential guidance for monitoring and regulation of pollutants in urban waterways worldwide.
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Doyle, James. "Mass Balance Tracer Techniques for Integrating in situ Soil Ingestion Rates into Human and Ecological Risk Assessments." Thesis, Université d'Ottawa / University of Ottawa, 2012. http://hdl.handle.net/10393/20557.
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Quantitative soil ingestion studies employing a mass balance tracer approach have been used to determine soil ingestion rate for use in human health risk assessments (HHRAs). Past studies have focused on soil ingestion in populations living in urban/suburban environments and the results have been highly variable. Moreover, there is a paucity of reliable quantitative soil ingestion data to support human health risk assessments of other lifestyles that may be predisposed to ingesting soil, such as indigenous populations following traditional lifestyles. Thus, the primary objective of the research was to determine if populations following lifestyles typical of traditional land use practices in rural or wilderness areas ingest more soil than populations living in urban or suburban environments. Further, the research investigated the use of alternative mass balance tracers, specifically isotopes of the 238U and 232Th decay series, to reduce soil ingestion estimate variability. Mass balance tracer methods were developed and validated in a pilot canine study, and methods using isotope tracers were adapted to permit quantification of sediment ingestion in the benthic fish Moxostoma macrolepidotum (Shorthead Redhorse Sucker). A pilot human soil ingestion study of 7 subjects from an Aboriginal community in British Columbia was conducted over a 3-week period. The mean soil ingestion rate calculated using the daily means of the 4 elemental tracers with the lowest food-to-soil ratios (i.e., Al, Ce, La, Si) was observed to be approximately 74 mg d-1 (standard deviation 91 mg d-1), The median soil ingestion rate was 60 mg d-1, and the 90th percentile was 196 mg d-1. These soil ingestion rate estimates are higher than those currently recommended for HHRAs of adults, and higher than those obtained in most previous studies of adults. However, the estimates are much lower than the earlier qualitative assessments for subsistence lifestyles (i.e., 330-400 mg d-1). The study results also demonstrated that isotopes of the 238U and 232Th decay series radionuclide are not reliable mass balance tracers for estimating soil ingestion in humans; however, they may be useful for quantifying soil and sediment ingestion in wildlife.
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Semenzin, Elena <1977>. "Site-specific ecological risk assessment (ERA) for contaminated sites: development of support tools for the risk estimation and characterization." Doctoral thesis, Università Ca' Foscari Venezia, 2007. http://hdl.handle.net/10579/798.
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Takahashi, Eri. "Risk Assessment of Marine Algal Toxins on Humans and Dugongs." Thesis, Griffith University, 2007. http://hdl.handle.net/10072/367296.
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Algal toxins can have a significant impact on human and ecological health as the toxins accumulate in the food chain and are consumed by both humans and marine organisms. This study focussed on the following marine algal toxins that were present at the study sites: okadaic acid (OA), domoic acid (DA), gymnodimine (GD), pectenotoxin-e (PTX-2) and PTX-2 seco acid (PTX-2SA). The study sites investigated for potential algal toxin exposure were selected from the waters around North Stradbroke Island, Queensland, Australia, where shellfish are harvested by the local population, and where dugongs are known to feed on seagrass. Samples were collected monthly for two consecutive years. The species of toxinproducing algae present at the sites studied were Pseudo-nizschia sp., Dinophysis caudata, D. acuminata and Prorocentrum lima. The occurrence of Dinophysis species was observed to be dependent on the season while Pseudo-nitzschia sp was present both in colder and warmer months. Data on the dose-response analysis were extracted from published literature. This data was categorised into whole organisms, human and animal cell lines, and compared to one another. For further toxicodynamic studies, human cell lines were dosed with known concentrations of the toxins: OA, DA and GD. These cytotoxicity and microarray analyses were performed to observe the effects of toxins on gene regulation. A more extensive analysis was performed using GD alone. Expression of numerous genes was affected, and real time polymerase chain reaction reactions were performed to confirm the regulation of those genes. Gymnodimine was demonstrated to affect genes within pathways relating to oxidative phosphorylation, apoptosis, MAPK and Wnt signalling pathways. The cytotoxicity and microarray data and the data accumulated from the published literature were combined to form a comprehensive database of both chronic and acute effects. The database was then referred to for the dose-response analysis for the risk assessment. The exposure data attained from field sampling in the current study was analysed against the doses for any shown effects. Total daily intake for humans and dugongs sourcing food from around the island were calculated and health risks were estimated by incorporating tolerable daily intake, guideline values and total daily intake. The risk characteristics of algal toxins on the health of humans (consuming shellfish) and dugongs (consuming seagrass) indicated that acute health risks were unlikely, unless an outbreak of toxic algae (algal bloom) were to occur. Since there were no occurrences of algal blooms during the study period, high levels of toxins were not detected in any of the collected shellfish, phytoplankton or seagrass samples. However, if such blooms were to occur around the island, the phytoplankton could potentially produce algal toxins at high enough concentrations to cause acute toxic effects in the consumers. The current study has also demonstrated that there is a potential for chronic, long term health effects from consuming shellfish and seagrass around the island. The presence of low-level concentrations of algal toxins in the food sources can lead to chronic effects. Toxins such as OA are known tumour promoters. For dugongs, which feed on seagrass on daily basis, the potential for chronic effects is high. It was demonstrated that GD also possesses toxicological characteristics that may enhance the possibility of tumour promotion because of its effect of down-regulating parts of the apoptosis pathway, which may prevent cell death and as a consequence, lead to uncontrolled cell growth.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Environment
Faculty of Science, Environment, Engineering and Technology
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Hau, Jorge Luis. "Toward environmentally conscious process systems engineering via joint thermodynamic accounting of industrial and ecological systems." Connect to resource, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1117650243.
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Thesis (Ph. D.)--Ohio State University, 2005.Title from first page of PDF file. Document formatted into pages; contains xxii, 306 p.; also includes graphics. Includes bibliographical references (p. 290-306). Available online via OhioLINK's ETD Center
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Schad, Thorsten [Verfasser]. "Xplicit – a modelling framework for ecological risk characterisation at landscape-scales in regulatory risk assessment and risk managementof plant protection products / Thorsten Schad." Landau : Universitätsbibliothek Landau, 2013. http://d-nb.info/1037920015/34.
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Isigonis, Panagiotis. "A decision support system for probabilistic ecological risk assessment (PERA) of pollutants on aquatic ecosystems." Doctoral thesis, Ca Foscari University of Venice, 2015. http://hdl.handle.net/10278/3715744.
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Ecological Risk Assessment (ERA) is a process undertaken for estimating the environmental harms caused by human activities. The assessment is based on three components: effect assessment, exposure assessment, and risk characterisation. The latter is a combination of the former two. Various methodologies can be used for performing ERA, which can be categorised into deterministic and probabilistic. Probabilistic techniques have been at the focus of research the last years, due to their elaborated character and the possibilities they offer for more refined risk assessments.
Despite their obvious advantages, probabilistic techniques present also disadvantages and challenges that need to be tackled. In the thesis, the possibility of exploring further the concept of Probabilistic Ecological Risk Assessment (PERA) is addressed. The main motivation of the thesis is identified in the effort to combine various well known concepts and methods for Ecological Risk Assessment, while enhancing them with new features and functionalities to serve the current needs of Risk Assessors. Therefore, providing a complete software package that allows performing efficient Propabilistic ERA (PERA) and offers related functionalities, all gathered in one place. The proposed software is developed as part of the research project AMORE (funded by the National French Research Academy – ANR).
A proposal for a Decision Support System (DSS), named AMORE DSS, supporting Probabilistic ERA is described in detail and validated through the application of the proposed DSS to a case study for assessing the effects and risks posed by the presence of cyanide in a river in north-western France. The AMORE DSS aims at allowing efficient Probabilistic ERA and tackles issues related with PERA and the concept of weighted Species Sensitivity Distributions (SSWD) such as the handling of uncertainty in PERA, the production of reliable SSWD graphs and the assessment of the quality of ecotoxicological data.
The theoretical section of the thesis is split into two main parts. In the first, the concept of Ecological Risk Assessment is introduced and the principal methods of interest are described. It is followed by the presentation of the concepts of Multi-Criteria Decision Analysis (MCDA) and Decision Support Systems (DSS), which are important aspects of the developed research.
The methodological developments of the thesis are based on a proposal for the estimation of the reliability and relevance of ecotoxicological data used in ERA, which is presented in detail and evaluated. The proposed methodology is based on Multi-Criteria Decision Analysis and allows the assessment of ecotoxicological data on the basis of a fixed set of criteria and mathematically stable and robust aggregation techniques. Therefore, the methodology suggests the production of reliable weighted Species Sensitivity Distributions, a vital component of the probabilistic ERA and the calculation of risk probabilities. The proposal allows incorporating in the risk assessment the knowledge gathered from an expert panel and gives significant strength to the risk assessors for the performed assessments, through the use of previously not widely available information and expertise.
The proposed DSS is built on the three components (exposure, effects, risk) of ERA and provides a complete set of functionalities to the risk assessors, enhanced with unique features. The thesis describes in detail the development of the software and the functionalities of each of its modules. The Exposure Assessment module aims at providing to the Decision Maker/Risk Assessor a collection of tools for the statistical analysis of environmental exposure data, through the concept of Predicted Environmental Concentration. The Effect Assessment module is based on the concept of weighted Species Sensitivity Distributions (SSWD) and incorporates the proposed methodology for the assessment of the reliability and relevance of ecotoxicological data. The Risk Assessment module is based on the concept of Potentially Affected Fraction (PAF) and aims at synthesising the results of the previous two modules for the estimation of risks, in an efficient and easy to present way.
The last part of the thesis is dedicated to the application of the DSS to a real life case study. A Risk Assessment process is performed for estimating the sensitivity of species to the presence of Cyanide (CN) in the environment, for estimating Environmental Quality Criteria (EQC) for the assessed case and for estimating the level of risk posed from Cyanide at the ecosystem. The assessed area is the Selune rivershed in the Manche department of the lower Normandy region in France, where four sampling stations have been identified with records of Cyanide presence for the period 2005-2014. Regarding the ecotoxicological data of the case study, 26 scientific articles on cyanide toxicity, published in the period 1965-2011, have been analysed for the extraction and assessment of 46 toxicological endpoints for the aquatic environment.
The case study is firstly based on all the available ecotoxicological data and secondly based on data split per taxonomic groups (i.e vertebrates, invertebrates) and trophic levels (i.e. primary producers, primary/secondary consumers). Specifically, six (6) sets of SSWD graphs are produced (i.e. All data, Vertebrates, Invertebrates, Primary producers, Primary consumers, Secondary consumers) with the use of two weighting options: (i) the weighting coefficients that are produced with the application of the MCDA based methodology and (ii) equal weighting coefficients for all the data. A comprehensive comparison of the two types of SSWD is performed and discussed in detail for the identification of the appropriateness of the fitting of the SSD curves to the experimental data. Hazardous concentrations (HCx) are estimated and presented for all the taxonomic groups and trophic levels. In addition, in combination with the results of the statistical analysis of the environmental exposure data, the risk is estimated for the assessed stations in the case study area. The results of the case study show that the primary producers are found to be the most sensitive trophic level while Invertebrates are more sensitive as a taxonomic group for low cyanide concentrations and Vertebrates are more sensitive for higher concentrations. Regarding the calculated risk indices, station 3 (L’Yvrande) of the Manche region is the area with the higher estimated risk.
The performed application of the DSS in the cyanide case study demonstrates a complete probabilistic Ecological Risk Assessment process with the use of Species Sensitivity Distributions and the utilisation of Multi-Criteria Decision Analysis. The case study, alongside with the validation of the developed DSS, demonstrates the performance of the proposed MCDA-based WoE framework for the analysis of ecotoxicological data, based on three distinctive Lines of Evidence (Experimental Reliability, Statistical Reliability, Biological Relevance). The framework and the related MCDA methodology constitute an innovative development in the field of quantitative ecotoxicological data assessment frameworks. Furthermore, a robust performance of the DSS has been identified, which allows potential for adoption within the risk assessment research fields.The thesis is concluded with future considerations for the developed DSS, which could provide interesting functionalities and extensions of the capabilities of the software.
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Isigonis, Panagiotis <1983>. "A decision support system for probabilistic ecological risk assessment (PERA) of pollutants on aquatic ecosystems." Doctoral thesis, Università Ca' Foscari Venezia, 2014. http://hdl.handle.net/10579/5636.
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The thesis is related with the development of a fully functional, modular Decision Support System (DSS) for performing Probabilistic Ecological Risk Assessment (PERA) of pollutants in aquatic environments. The Decision Support System is a 3‐module software, which integrates the use of Multi‐Criteria Decision Analysis (MCDA) methods for the quantitative assessment of the reliability and relevance of ecotoxicological data. Ecotoxicological data are vital components of the Ecological Risk Assessment processes and specifically the Effect assessment part. A MCDA based methodology (i.e. from the definition of the conceptual framework to the software implementation in collaboration with an experienced programmer) has been fully developed for the assessment of ecotoxicological data, which are used for the creation of weighted Species Sensitivity Distribution (SSWD) graphs. The innovative MCDA based methodology allows the assessment of ecotoxicological data based on a set of 57 distinctive criteria and gives the possibility to researchers to classify and rank ecotoxicological data, based on their various characteristics.
As part of the research project, a case study application has been performed for the analysis of the ecological risk from the presence of cyanide in the Sélune watershed, at the Manche region of the Lower Normandy in the north‐west part of France. Environmental exposure data of cyanide (CN) have been collected from the Water Agency of ‘Seine‐Normandie’ and used in the Exposure Assessment module, while ecotoxicological data for cyanide gathered from peer‐reviewed publications have been analysed with the use of the proposed MCDA based methodology, in the Effect Assessment module. The ecological risk assessment process was concluded with the calculation of the risk indices in the last module of the DSS.
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Preston, Benjamin Lee. "Toxicant interactions with the biotic and abiotic environment of freshwater rotifers : implications for ecological risk assessment." Diss., Georgia Institute of Technology, 2000. http://hdl.handle.net/1853/25217.
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Mattson-Hansen, Kimberly M. "Modeling Ecological Risks at a Landscape Scale: Threat Assessment in the Upper Tennessee River Basin." Diss., Virginia Tech, 2016. http://hdl.handle.net/10919/78611.
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There is no single methodology toward freshwater conservation planning, and few analytical tools exist for summarizing ecological risks at a landscape scale. I constructed a relative risk model, the Ecological Risk Index (ERI), to combine the frequency and severity of human-induced stressors with mappable land and water use data to evaluate impacts to five major biotic drivers: energy sources, physical habitat, flow regime, water quality, and biotic interactions. It assigns 3 final risk rankings based on a user-specified spatial grain. In a case study of the 5 major drainages within the upper Tennessee River basin (UTRB), U.S.A, differences in risk patterns among drainages reflected dominant land uses, such as mining and agriculture. A principal components analysis showed that localized, moderately severe threats accounted for most of the threat composition differences among watersheds. Also, the relative importance of threats is sensitive to the spatial grain of the analysis.
An evaluation of the ERI procedures showed that the protocol is sensitive to how extent and severity of risk are defined, and threat frequency-class criteria strongly influenced final risk rankings. Multivariate analysis tested for model robustness and assessed the influence of expert judgment by comparing my original approach to a quantile-based approach. Results suggest that experts were less likely to assign catchments to high-risk categories than was the quantile approach, and that 3 final risk rankings were appropriate.
I evaluated the influence of land use on freshwater ecosystems by studying the relationship between land cover changes and the persistence of freshwater mussels. First, historical species data were collected and the Upper Tennessee River Mussel Database (UTRMD) was constructed. The UTRMD contains >47,400 species records from 1963-2008 distributed across nearly 2,100 sampling sites.
My study suggests that 30 years of land cover change does not explain observed freshwater mussel declines. Quantitative surveys are recommended basin-wide to provide more accurate information about mussel distribution and abundance. Lastly, results suggest that streams with repeated mussel surveys have increasing populations, including active recruitment in several beds. Additional quantitative surveys since 2004 have probably provided more accurate species and population counts, although actual population sizes are still uncertain.Ph. D.
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Carlisle, Margaret. "Lead poisoning in the Spanish eagle population of the Doñana, SW Spain : an ecological risk assessment." Thesis, University of Aberdeen, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.419652.
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Doñana National Park in south-west Spain is one of the last remaining strongholds of the Spanish Imperial eagle Aquila adalberti, which is one of the world’s rarest birds with only around 150 pairs remaining. Lead poisoning is known to be a problem that affects other eagle species, and the purpose of this thesis is to determine whether this is a potential problem for the Doñana population of eagles. Bird exposure to lead in this area is estimated to come from two main sources, soil and sediment lead from upriver mining operations including the 1998 Aznalcollar toxic spill, and resident lead shot due to long-term hunting activity. a soil lead distribution model is constructed for the whole Doñana, using known principles of pollution deposition in combination with satellite imagery analysis and a training dataset of soil samples dating from 1983 to the present. A lead shot distribution model is also constructed for the whole Doñana, using a simple rule-based approach to estimate the maximum niche of availability for this lead source. A Monte Carlo simulation model is developed to model the processes of transfer of lead to eagles via their prey species Greylag geese Anser anser and Mallard ducks Anas platyrhynchos. The model predicts potentially high (5.2%) probability of an eagle being lead poisoned. A GIS-based ecological risk assessment model quantifies the spatial pattern of lead shot ingestion for Greylag geese and Mallard ducks and grades each of Doñana’s eagle territories according to their lead risk value. The sensitivity, uncertainty and error for all of the above models are assessed in detail. Finally, future research needs are identified, conservation actions prioritised and management decisions recommended.
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Sciera, Katherine Lynne. "Quantifying the effects of land use change on stream ecosystems for use in ecological risk assessment." Connect to this title online, 2008. http://etd.lib.clemson.edu/documents/1233081388/.
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Prokofyeva, Evgeniya. "The application of diffusion gradient method (DGT) for ecological risk assessment of natural and artificial matrixes." Doctoral thesis, Università Politecnica delle Marche, 2015. http://hdl.handle.net/11566/243013.
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Il lavoro presenta le attività condotte per studiare, nell'ambito della valutazione di rischio ambientale, un metodo che descriva quantitativamente la mobilità di inquinanti organici persistenti nella fase solida del suolo e dei sedimenti.
Il lavoro ha implicato la progettazione e la realizzazione di una sonda passiva in grado di campionare per diffusione le molecole organiche (Organic Diffusive Probe, ODP). La sonda ODP riproduce le condizioni necessarie per attuare la tecnica del gradiente diffusivo su strato sottile (Diffusion Gradients in Thin-film, DGT) ed è stata progettata adattando lo schema della sonda DGT, originarialmente pensata per il campionamento dei metalli pesanti. Le principali modifiche sono quelle relative ai materiali utilizzabili, come recettori dei contaminanti e come riempimento dello strato diffusivo, e all'aspetto esteriore della sonda.
La sonda è stata calibrata usando carbone attivo come materiale recettore. Quindi, sono stati studiati sia l'influenza della geometria della sonda (rapporto superficie/spessore diffusivo) che quella dei parametri chimicofisici del suolo sull'adsorbimento degli inquinanti organici. È stata anche presa in esame l'influenza delle diverse concentrazioni di inquinante a parità di suolo e di suoli con diverse proprietà chimicofisiche a parità di concentrazione inquinante. I risultati mostrano la fattibilità dell'applicazione della tecnica DGT alla valutazione del rischio ambientale da inquinanti organici persistenti.
La ricerca ha infine preso in considerazione l'applicazione della sonda su due casi studio di suolo e sedimento. Il primo ha esaminato campioni di suolo provenienti dal sito contaminato dell'impianto di coke della Novolipetsk Steel. Nel secondo la tecnica DGT è stata applicata all'analisi di Idrocarburi Policiclici Aromatici su sedimenti marini dell'Adriatico. I risultati confermano la possiblità di applicare la sonda per la misura della frazione organica labile nel suolo e nel sedimento.This work is devoted to describing the activities performed to test a method for measuring the mobility of persistent organic pollutants in the solid phase of soils or sediments within the context of environmental pollution risk assessment. The method is based on the design of a new probe for the passive sampling of organic pollutant in soils. The probe, namely an organic diffusive probe (ODP), was prepared to reproduce diffusion gradients in thin-films (DGT). The new probe is designed by adapting DGT, originally meant for heavy metals, to organic molecules. The main modifications relate to: the material suitable as organic pollutant receptor; the shape of the overall testing device and the materials filling the probe. The ODP was calibrated with activated carbon as a receptor material. Moreover, the influence of geometric characteristics of the probe and the influence of different physicochemical soil parameters on adsorption of organic pollutants were studied. Furthermore, were investigated influences of different concentration of pollutant in samples from one type of soil and the same concentration of the pollutant in samples with different physiochemical properties. Results from ODP experiments showed the feasibility of application of the diffusion gradient for environmental risk assessment of pollution by organic compounds. Further research has been focused on practical applications of the diffusion gradient method. The study included the testing of the principle of diffusion gradient on soil samples from coke production site, Novolipetsk Steel company. The latest work has been concentrated on analysing diffusion processes of polycyclic aromatic hydrocarbons (PAHs) in sediments of the Adriatic Sea. These results confirm the possibility of applying such adopted configurations of the passive probe that is able to measure the labile fraction of organic pollutants in soils and sediments.
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Huang, Yanran. "Exposure and risk assessment of organic UV filters : from environmental occurrence to human biomonitoring study." HKBU Institutional Repository, 2020. https://repository.hkbu.edu.hk/etd_oa/740.
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In recent years, the studies of emerging contaminants have received growing concerns due to their ambiguous fate and unclear effect to the water environment, aquatic organisms or even human. With the development of the analytical techniques, the increase detection rate of emerging contaminants is at a rapid pace that many of their fates and influence are still pending investigation. In this work, a group of organic UV filters, which is one of the vital categories of emerging contaminants are monitored. Organic UV filters, used as the major components in not only sunscreens but also other cosmetics products, have a widespread usage and large production volume for more than 80 years, causing the massive input towards the aquatic environment. To first investigate their environmental behaviours and impacts, the regional distribution of total nine commonly used organic UV filters was monitored along the southeast coastline of Shenzhen, which is the most rapid developing city in China with large population with the consideration of seasonal variation. In addition, the Shenzhen reservoirs, as the major sources of drinking water in Shenzhen, was also monitored together with the city tap water. The results indicated the extensive distribution of certain kinds of UV filters with obvious seasonal pattern, which may cause medium to high risk to aquatic organisms. And the incomplete removal of them in drinking water supply system resulting trace amount of UV filters to be detected in city tap water, may cause a general exposure of these UV filters towards all populations. Therefore, a quantitative analytical method for simultaneous detecting multiple classes UV filters in human urine samples has been developed and applied on more than 100 real samples for determining internal exposure. Similar UV filters were also detected in human urine samples compared with surface water while one of the most commonly used organic UV filters, Ethylhexyl methoxycinnamate exhibited much lower detection rate and concentration in human urine. Then, biotransformation of Ethylhexyl methoxycinnamate was examined in rats for the purpose of selecting suitable metabolites as exposure biomarkers. Several metabolites have been identified in urine and plasma by UHPLC-QTOF-MS. Two of its metabolites, 4-methoxycinnamic acid and 4' -methoxyacetophenone, were unambiguously identified by comparing with commercial standard. Excretion trend of Ethylhexyl methoxycinnamate and its two metabolites confirmed that most of the parent compound were quickly metabolized and excreted through urine samples. Herein, these three targeted compounds were further evaluated in two populations - female university students and school-aged children. Although Ethylhexyl methoxycinnamate was not detected in 49 female university students, significant internal correlations were discovered among these three analytes in school-aged students and extensive detection of metabolites instead of parent compound was also confirmed. The third part of this thesis is to comprehensively monitor the internal exposure of UV filters and their metabolites, and also discover their potential adverse health impacts - obesity in Shanghai children and adolescents. Urinary concentration of certain kinds of UV filters were significantly higher in girls than in boys. However, further associations have been found with urinary Ethylhexyl methoxycinnamate concentration and reduced adiposity outcomes only in boys, indicating it may have the potential to influence the metabolism in male population during growing stage. In short, a complete study of organic UV filters is presented in this thesis, from their environmental occurrence to metabolism in animal models, and finally to human exposure and potential health impacts. The widespread exposure and significant associations with adiposity outcomes can form a solid base for future comprehensive risk assessment of UV filters towards human health
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Pereira, Ana Carina Santos. "Linking exposure of mediterranean freshwater ecosystems to pesticides mixtures with their environmental side-effects." Doctoral thesis, ISA, 2017. http://hdl.handle.net/10400.5/14958.
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Doutoramento em Engenharia do Ambiente - Instituto Superior de AgronomiaIn freshwater ecosystems associated with agricultural areas, organisms are exposed to a multitude of toxicologically and structurally distinct pesticides in concentrations that may fluctuate over time. However, the environmental risks of chemicals are traditionally evaluated and regulated on the basis of single substance. Understanding and improving the link between effects and exposure assessment is an important step in the current challenges of risk assessment in order to increase its ecological relevance. To this end, integrated approaches of different hierarchical levels of complexity and ecological realism have been developed and applied, including: exposure modelling, laboratory testing with individual organisms, species sensitivity distribution, ecosystem models and assessment of aquatic community interactions to evaluate the effects of realistic pesticide combinations on water bodies associated with rice, tomato and maize typical agroecosystems of Mediterranean conditions. Contributing to the overall knowledge of the adequacy of the prospective risk assessment and demonstrating that pesticide risk may be underestimated during the actual registration procedure. The data generated in the present study contributed to the derivation of optimized programs of measures under the scope of European legislation; the identification of sites with the highest expected impacts of pesticide mixtures; the evaluation of the major pesticide compounds that contributed mostly to the identified aquatic risks. Furthermore contribute to a deeper knowledge and unravel the effects of co-occurring chemicals, environmental and biological stressors in aquatic ecosystems considering the effects of biotic and abiotic interactions at community and ecosystem levels. The results contribute to reducing the risks of pesticides in freshwater
N/A
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Ching, C. Y. Terrance, and 程振英. "Deriving critical tissue concentrations of trace metals in fishes for ecology risk assessment." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B45013718.
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Arteaga, Jorge Lobo. "Evaluation of the potential of translocated common cockle for ecological risk assessment studies: bioaccumulation and biomarkers test." Master's thesis, FCT - UNL, 2009. http://hdl.handle.net/10362/2504.
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Thesis submitted to the Faculdade de Ciências e Tecnologia to obtain the Master’s degree in Environmental Engineering, profile in Ecological EngineeringSediment–bound contamination is a major concern factor in estuaries and other confined coastal water bodies, frequently subjected to anthropogenic sources of pollution. In order to investigate the effects and responses of the common cockle (Cerastoderma edule, L. 1558, Bivalvia: Cardiidae) to sediment contaminants and to assess the species’ potential as an indicator organism, the bivalve was subjected to a laboratorial translocation assay with sediments collected from distinct sites of the Sado Estuary (Portugal). Cockles were collected from a mariculture site of the Sado estuary (Portugal), herewith identified as site A, and exposed through 28–day, semi–static laboratorial essays, to sediments collected from three other sites (B, C and D) of the estuary that revealed different levels of metals, organic contaminants and physico–chemical properties and that ranged from globally unimpacted to moderately impacted levels when compared to available sediment quality guidelines. The animals were surveyed for bioaccumulation of metals (Ni, Cu, Zn, As, Cd and Pb) and organic contaminants (PAHs, PCBs and DDTs). Two sets of potential biomarkers were employed to assess toxicity: whole–body metallothionein (MT) induction and digestive gland histopathology. The bioaccumulation factor (BAF) and the biota-to-soil accumulation factor(BSAF) were estimated as ecological indices of exposure to metals and organic compounds. Significant positive correlations between BSAF and MT were found for PHAs, and between each factor (BSAF and BAF) and MT were found for Cd. Histopathological alterations were found in cockles exposed to all sediments where they were translocated. The digestive gland integrity was found to be especially compromised in cockles from sediment B and C and at day 28 from sediment A. Results allowed concluding that C. edule responds to sediment–bound contamination and is capable to regulate and eliminate both types of contaminants and might, therefore, be suitable for biomonitoring. Still, the sediment contamination levels do not explain the variation in bioaccumulation and MT levels, which may result from the moderate contaminant concentrations found in sediments and, more importantly, from yet unexplained xenobiotic interaction effects.
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Plevrakis, Viktor. "Comparison of risk assessment methods for polluted soils in Sweden, Norway and Denmark." Thesis, Stockholms universitet, Institutionen för naturgeografi och kvartärgeologi (INK), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-109376.
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Land contamination is an acknowledged problem around the world due to its potentially adverse impacts on human health and the environment. Specifically in Europe there are estimated to be 2,500,000 potentially contaminated sites. The risk that contaminated sites pose is investigated by risk assessments. The methods and the models though used in risk assessments, vary both on a national and an international level. In this study, the risk assessment methods and models for polluted soils used in Scandinavia and issued by the Environmental Protection Agencies were compared. The comparison aimed to (i) identify similarities and differences in the risk assessment methodology and risk assessment methods and to (ii) investigate to which extend these differences can impact the results of the models and the implications regarding mitigation measures. The method and model comparison showed that Sweden and Norway have great similarities in assessing risks for contaminated soil. However, there are differences with Denmark on a conceptual level. When a common hypothetical petrol station with 20 soil samples was assessed, the results and the conclusions of the three risk assessments were quite different; the site was seen as posing risk to human health with the Danish model when complied with the quality criteria issued by the Norwegian model. The Swedish risk assessment concluded that the contaminant concentration in 3 out of 20 samples was potentially harmful for the environment but not for human health. The demonstrated divergence of the conclusions of risk assessments has major implications and shows great interest for mainly four groups: Land-owners who may be called to cover the expenses for remedial action. Consultants and companies who perform risk assessments and land remediation. The countries that have to meet national and international environmental goals and can also share/ or cover the cost for remedial action. The people exposed to such environments that could be deemed as potentially harmful by a neighboring country. The study was conducted in collaboration with URS Nordic.