Дисертації з теми "Assessment and management of freshwater ecosystems"
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Wilson, Gregory B. "Ecosystem-Based Management of the Lake Erie Ecosystem: A Survey-Based Approach to Assessment of Management Needs." Kent State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=kent1302202900.
Повний текст джерелаBrowne, Samantha. "The role of acute toxicity data for South African freshwater macroinvertebrates in the derivation of water quality guidelines for salinity." Thesis, Rhodes University, 2005. http://eprints.ru.ac.za/174/.
Повний текст джерелаAyas, Ceren. "Decoupling Developmentalism-environmentalism: Human Nature Conceptualizations In Freshwater Ecosystems Management In Turkey." Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/12611182/index.pdf.
Повний текст джерелаs limits remarks for non-teleological and eco-friendly ways of conceptualizing the relationship between human beings and nature is explored with an emphasis of &lsquo
who&rsquo
that is local, female, young, social science-based, active in civil movement. The objective of conducting the research is to find out the ways why green approaches in social, political and economic spheres in Turkey are not integrated as a first step to decouple the antagonism in man&rsquo
s relationship with nature. The analysis tried to grasp the discrepancies of conceptualizing human-nature relationship in order to find out which segment of the society would be closer to adopt green values, with the intention of proposing them to be involved in a greater extent to decision-making mechanisms with regards to natural resources management, as well as an attempt to grasp the overall picture in understanding nature-human relationship in Turkey by focusing on wetland management based on the research conducted in Bafa Lake (Aydin), Uluabat Lake (Bursa), Salt Lake (Konya) and Egirdir Lake (Isparta). Thanks to the scale that is constructed by operationalizing the existing debates on environmental ethics, agents that would follow more ecologically sound discipline towards living harmoniously within nature is analysed.
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.
Повний текст джерелаIn 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
Damiani, Mattia. "Addressing water consumption impacts on freshwater ecosystems : development of a regionalized, global habitat-based model for life cycle impact assessment." Thesis, Montpellier, SupAgro, 2018. http://www.theses.fr/2018NSAM0013.
Повний текст джерелаApproximately 65% of inland waters are under moderate or high threat by anthropogenic alteration and climate change. Earth has lost around half of inland water habitats in the last hundred years and global water withdrawal is expected to increase by more than 50% within the next 20 years. In this context, competition for water resources between humans and ecosystems is set to rise at the expense of freshwater-dependent biodiversity. For this reason, nowadays it is imperative to quantify and safeguard water needs of freshwater-dependent ecosystems.As a global tool to support decision-making, in life cycle assessment (LCA) several models for life cycle impact assessment (LCIA) of water consumption on ecosystems have been proposed. One important flaw of current LCIA models, whether they are mechanistic or non-mechanistic, midpoint or endpoint-oriented, is their limited consideration of environmental water requirements (EWR). For this reason, existing approaches for EWR assessment have been investigated to evaluate potential benefits of better including ecohydrological principles in LCIA on ecosystems.This enabled the definition of the concept of freshwater habitat within the boundaries of LCIA and the development of a framework for the application of habitat simulation methods in LCIA modeling. A midpoint habitat change potential (HCP) indicator assessing the impact of flow alteration on instream habitats of fish and invertebrates was developed. The new model has been tested on the French river network at the river reach scale, characterizing habitat change in wet and dry seasons. HCPs were then aggregated at watershed scale. The new model was subsequently generalized to allow global extension. Input variables of the generalized HCP model have been calculated from existing databases and models on a monthly resolution. Limitations, uncertainty and research perspectives of the new approach are discussed
Valentine, K. Hope. "Methods in health assessment of freshwater mussels, Amblema plicata and Quadrula spp." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1293654676.
Повний текст джерелаUyizeye, Erasme. "Developing an Odonate-Based Index for Monitoring Freshwater Ecosystems in Rwanda: Towards Linking Policy to Practice through Integrated and Adaptive Management." Antioch University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=antioch158827000356307.
Повний текст джерелаNikolakopoulou, Myrto-Georgia. "The functional role of emergent macrophytes in nature-based solutions (NBS) aiming to mitigate nutrient loading in freshwater ecosystems." Doctoral thesis, Universitat de Barcelona, 2021. http://hdl.handle.net/10803/672904.
Повний текст джерелаLa degradació dels ecosistemes aquàtics s’ha atribuït, en gran mesura, a l’excés de concentracions de nutrients d’origen antropogènic. Aquesta degradació, combinada amb l’escassetat d’aigua, és la principal causa de l’alarmant problemàtica dels recursos hídrics a nivell global. Donat que un terç de la població mundial no té accés a aigua potable, es fa imprescindible abordar la problemàtica de la contaminació per nutrients. El concepte de solució basada en la natura (SBN) ha aparegut recentment per designar aquelles tècniques inspirades en la natura que aborden diversos reptes socials tot preservant la sostenibilitat dels ecosistemes. La seguretat de poder disposar d'aigua es troba entre els desafiaments socials més importants que avui dia afronten les SBNs, essent la contaminació per nutrients en ecosistemes aquàtics un dels seus principals objectius. Si bé els SBN destinats a abordar la problemàtica de la càrrega de nutrients en sistemes aquàtics incorporen macròfits emergents en el seu disseny de forma rutinària, hi ha una manca de coneixement dels mecanismes que expliquen com aquestes plantes aquàtiques milloren el tractament de les aigües. En aquesta tesi doctoral, ens hem proposat reduir aquesta mancança del coneixement investigant com els trets físics, químics i biològics de les plantes influeixen en el medi aquàtic subsuperficial i com afecten la mitigació de nutrients. Concretament, hem examinat el transport de soluts a la subsuperficie i la retenció de nutrients sota la presència de tres espècies de macròfits emergents; Iris pseudacorus L., Phragmites australis L. i Scirpus lacustris L.. Addicionalment, hem explorat la influència de la qualitat del carboni orgànic dissolt en el cicle del nitrogen. Per portar a terme aquest objectiu, es van realitzar una sèrie de tres treballs dissenyats amb una mateixa configuració de 12 canals artificials experimentals, i on es van aplicar mètodes tradicionals de l’ecologia fluvial (és a dir, addicions sobtades de traçadors conservatius i d’elements reactius) per poder caracteritzar el transport subsuperficial de soluts i estimar les mètriques de l’espiral de nutrients. Igualment, es va modificar experimentalment el grau de labilitat del carboni en el sistema de canals, i es va caracteritzar l'arquitectura del sistema radicular d’aquests tres macròfits emergents. Quant a l’efecte físic dels macròfits, els resultats demostren que l’arquitectura radicular dels macròfits influeix substancialment en el transport subsuperficial dels soluts. Concretament, un sistema dens d’arrels fines dóna lloc a una major retenció hidràulica, mentre que una arquitectura d’arrels més gruixudes condueix a resultats inversos, donat que faciliten la infiltració a nivell intersticial. A més, hem constatat que la influència química i biològica dels macròfits emergents en el medi subsuperficial aquàtic és específica de cada espècie, i depèn de les diferències fisiològiques entre elles, i de la capacitat de les plantes per crear major temps de residència en el medi intersticial. Addicionalment, hem provat que la presència de macròfits emergents facilita l’eliminació de nitrogen, mentre que la disponibilitat d’una font de carboni làbil fa augmentar la respiració aeròbica microbiana en lloc de la desnitrificació. Finalment, a la discussió general de la tesi, es discuteixen els resultats obtinguts i es sintetitzen dins del context de les SBN amb informació extreta de la bibliografia. En general, la present tesi doctoral posa de manifest aspectes poc coneguts sobre el paper funcional dels macròfits emergents quant a la reducció de nutrients en les SBNs. També posa en relleu la importància de fer una selecció adequada d’espècies de macròfits per a sistemes on s’apliquen SBN a fi d’optimitzar el tractament d’aigües; i proporciona valuoses pautes per a professionals que apliquen SBNs per tal d’identificar les espècies de macròfits més apropiades per la reducció de nutrients.
Ho, Chi-fai, and 何志輝. "Ecological risk assessment and management of invasive freshwater fish species from aquarium and ornamental trades in Hong Kong." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2013. http://hdl.handle.net/10722/194580.
Повний текст джерелаpublished_or_final_version
Environmental Management
Master
Master of Science in Environmental Management
Figueroa-Cano, Maria Enedina. "Indicators for the assessment of the sustainability of anthropogenic ecosystems, a model development approach for watershed natural resources management." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/mq48572.pdf.
Повний текст джерелаWeiss, Steven P. "Bioassessment of the West Branch of the Wolf River /." Link to full text, 2007. http://epapers.uwsp.edu/thesis/2007/weiss.pdf.
Повний текст джерелаMathie, Devan M. "Assessing an In-Situ Total Algae Sensor Fluorometer for Performance in Freshwater Estuaries." Kent State University Honors College / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ksuhonors1588015130835849.
Повний текст джерелаBliss, Kevin R. "An outcome-based assessment of the New York State Department of Environmental Conservation freshwater wetlands regulatory system in Central New York." Thesis, State University of New York Col. of Environmental Science & Forestry, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3628499.
Повний текст джерелаThis dissertation evaluates freshwater wetland impact avoidance and mitigation resulting from the New York State Department of Environmental Conservation (NYSDEC) permitting program within Central New York. Concurrent with this, is an effort to ascertain wetland functionality through a rapid assessment approach to wetland evaluation. Three primary techniques were employed: First, NYSDEC permit decisions were compared to the NYSDEC Freshwater Wetland Regulation Guidelines on Compensatory Mitigation (NYSDEC 1993), to determine whether or not the Guidance was adhered to. Second, NYSDEC permit requirements were compared to the actual mitigation efforts conducted by a permittee in the field to determine whether or not the permittee complied with imposed requirements. And third, a rapid assessment approach comparing functions and values at wetland mitigation sites to the corresponding natural wetland that was impacted by NYSDEC permit issuance was used to determine whether or not the functions and values provided by the mitigation adequately replaced those lost at the original impacted wetland site. The results of this review indicate that the majority of wetland mitigation guidelines are not followed the majority of time. For example, less than one third of the time was mitigation based on plans providing short or long term goals or measurable performance criteria. Often permittees do not comply with imposed freshwater wetland permit requirements related to mitigation. More specifically, thirty five percent of the time, permit requirements for mitigation were not met for those files sampled. As for the functions and values being replaced, that is not happening with six out of nine measured functions: open space and aesthetic resources; erosion control; pollution treatment; protection of subsurface water resources; wildlife habitat; and flood control. The three functions found to be replaced by mitigation include recreation; sources of nutrients in freshwater food cycles and nursery grounds / sanctuaries for freshwater fish; and education and scientific research.
Reap, John J. "Plants in the garden an approach to modeling the impact of industrial activities in ecosystems /." Thesis, Available online, Georgia Institute of Technology, 2004:, 2004. http://etd.gatech.edu/theses/available/etd-04082004-201301/unrestricted/reap%5Fjohn%5Fj%5F200405%5Fmast.pdf.
Повний текст джерелаMatthew J. Realff, Committee Member ; Farrokh Mistree, Committee Member ; Berdinus A. Bras, Committee Chair. Includes bibliographical references (leaves 191-195).
Wangai, Peter Waweru [Verfasser]. "Mapping and assessment of ecosystem services to improve resource management and human wellbeing in data-scarce peri-urban ecosystems / Peter Waweru Wangai." Kiel : Universitätsbibliothek Kiel, 2017. http://d-nb.info/1140054120/34.
Повний текст джерелаWangai, Peter W. [Verfasser]. "Mapping and assessment of ecosystem services to improve resource management and human wellbeing in data-scarce peri-urban ecosystems / Peter Waweru Wangai." Kiel : Universitätsbibliothek Kiel, 2017. http://d-nb.info/1140054120/34.
Повний текст джерелаDillon, Rebecca. "Re-evaluation of north-temperate reservoir food web interactions and their assessment." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1594472755977476.
Повний текст джерелаGordon, Line. "Land Use, Freshwater Flows and Ecosystem Services in an Era of Global Change." Doctoral thesis, Stockholm : Univ, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-16.
Повний текст джерелаSantos, Martha Raquel Pereira. "Bacterial community as a complementary tool to the water directive framework in ecological quality assessment of Caima river." Master's thesis, Universidade de Aveiro, 2017. http://hdl.handle.net/10773/21461.
Повний текст джерелаFreshwater ecosystems have been suffering severe degradation and loss of biodiversity, caused by human disturbances such as agriculture, industry, mining, urban development and climate changes. Therefore, the European Union reached an agreement and implemented the Water Framework Directive (WFD), with the main goal of reach a good ecological status in all water bodies. However, WFD is very complex, methodologies are time-consuming and costly. Thus, the main objective of this study is to develop a rapid and cost-effective approach, by studying the bacterial community composition by flow cytometry, as a complementary methodology to WFD. To achieve this, we study 3 sampling sites at Caima River along the seasons (winter, spring and summer), with different levels of environmental impacts (Nascente- river source- with little impact, Bustelo- downstream WWTP and Palhal- exposed to mine drainage), applying first the WFD criteria and then multivariate analysis for macroinvertebrate, periphyton and bacteria communities. Physico-chemical, metals and bacteria samples were collected from the water column and sediment river bottom, showing that in all the parameters (with some exceptions) and metals the concentrations were higher in sediments. Results showed that not always the macroinvertebrate and periphyton communities were sensitive to an increased nutrient input, resulting in an ecological status higher than expected. On the other hand, community structure analysis for macroinvertebrates and periphyton was very discriminatory, associating high levels of nutrients and metals with more tolerant organisms in impacted sites, and sensitive organisms with high levels of dissolved oxygen corresponding to pristine environments. Bacteria community analysis revealed a clear separation of LNA and HNA bacteria in sediment according to the different environmental stress, being possible to dissociate the majority of the impacted sites from the clean sites, being HNA a good indicator of contamination. These results revealed that bacteria community in sediments has more reliable data about the impacts that a freshwater ecosystem can suffer. The discriminating power of bacteria community analyzed by FCM provided good responses, although, further investigations are needed to confirm the feasibility of this new method, as a complementary tool in the water quality assessment.
Os sistemas aquáticos de água doce têm vindo a sofrer uma severa degradação e perda de biodiversidade, derivado de atividades humanas como a agricultura, indústria, atividades mineiras desenvolvimento urbano e alterações climáticas. Assim, a União Europeia implementou a Diretiva Quadro da Água (DQA), com o principal objetivo de atingir o bom estado ecológico em todas as massas de água. No entanto, a DQA revelou ser bastante complexa, com metodologias muito morosas e dispendiosas. Com este estudo, pretende-se desenvolver uma metodologia rápida e económica, estudando a composição da comunidade bacteriana por citometria de fluxo, como ferramenta complementar à DQA. Para a concretização deste trabalho, foram estudados 3 locais do rio Caima com diferentes tipos de impactos: a nascente – local de referência; Bustelo - a jusante de uma estação de tratamento de águas residuais e o Palhal - com escorrências provenientes de uma mina desativada, no inverno, primavera e verão aplicando a metodologia estabelecidas pela DQA usando os macroinvertebrados e perifiton como comunidades biológicas estudadas. Adicionalmente foi aplicada a análise multivariada aos dados recolhidos por citometria de fluxo à comunidade de bactérias da coluna de água e dos elutriados dos sedimentos e aos resultados das comunidades de macroinvertebrados e perifiton obtidos da DQA. No geral, os parâmetros físico-químicos, e as quantificações de metais mostraram valores mais elevados nos elutriados dos sedimentos do rio, do que na coluna de água mostrando a importância da análise desta matriz que não está contemplada na DQA. Resultados sensu DQA mostraram que nem sempre as comunidades de macroinvertebrados e perifiton foram concordantes na resposta aos diferentes tipos de impactos e que a qualidade ecológica dos locais avaliados foi melhor do que era expectável. Por outro lado, a análise multivariada das comunidades de macroinvertebrados e perifiton foi bastante discriminatória, associando elevados níveis de nutrientes e metais com organismos mais tolerantes, que se encontram em locais mais impactados, e organismos sensíveis com altos níveis de oxigénio dissolvido em locais mais pristinos. A análise da comunidade bacteriana revelou uma distinta separação entre bactérias LNA e HNA nos sedimentos, de acordo com os diferentes stresses ambientais, sendo HNA, nos sedimentos, um ótimo indicador de contaminação. Estes resultados revelam que a comunidade bacteriana oferece uma boa resolução de locais contaminados usando a citometria de fluxo como metodologia rápida de avaliação complementar à avaliação do estado ecológico sensu DQA sendo, no entanto, necessárias mais estudos aplicados a outras tipologias de rios e outros tipos de impactos para confirmar a validade desta nova metodologia.
Buzulencia, Hayley Catherine. "THE CHARACTERIZATION AND SURVEY OF INORGANIC SULFUR REDOX ASSOCIATED WITH WETLAND HYDROLOGICAL FLUCTUATIONS." Kent State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=kent1574288446961206.
Повний текст джерелаJackson, Breeanne Kathleen. "The role of wildfire in shaping the structure and function of California `Mediterranean’ stream-riparian ecosystems in Yosemite National Park." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1431014316.
Повний текст джерелаNolfi, Daniel C. "National Park Service Cave and Karst Resources Management Case Study: Great Smoky Mountains National Park." TopSCHOLAR®, 2011. http://digitalcommons.wku.edu/theses/1053.
Повний текст джерелаMaseti, Pumza Penelope. "Biomonitoring in two contrasting catchments." Thesis, Rhodes University, 2006. http://hdl.handle.net/10962/d1006175.
Повний текст джерелаFordham, Colin Justin. "A spatial and temporal analysis of the changes in alien macrophyte communities and a baseline assessment of the macroinvertebrates associated with Eurasian watermilfoil, Myriophyllum spicatum L. (Haloragaceae) in the Vaal River." Thesis, Rhodes University, 2012. http://hdl.handle.net/10962/d1005455.
Повний текст джерелаIranawati, Feni. "An assessment of the geographical scale of recurrent gene flow in wild populations of two species of Mekong River carps (Henicorhynchus spp.)." Thesis, Queensland University of Technology, 2014. https://eprints.qut.edu.au/71217/1/Feni_Iranawati_Thesis.pdf.
Повний текст джерелаTengö, Maria. "Management Practices for Dealing with Uncertainty and Change : Social-Ecological Systems in Tanzania and Madagascar." Doctoral thesis, Stockholms universitet, Institutionen för systemekologi, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-309.
Повний текст джерелаAlaibakhsh, Masoomeh. "Digital change detection and separation of anthropogenic and natural impacts on ecohydrological conditions in the Pilbara region, WA." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2017. https://ro.ecu.edu.au/theses/1951.
Повний текст джерелаSimaika, John P. "Conservation biogeography of South African dragonflies (Odonata)." Thesis, Link to the online version, 2008. http://hdl.handle.net/10019/1711.
Повний текст джерелаWilbur, Cricket C. "A History of Place: Using Phytolith Analysis to Discern Holocene Vegetation Change on Sanak Island, Western Gulf of Alaska." Antioch University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=antioch1395927847.
Повний текст джерелаPittock, Jamie. "Integrating management of freshwater ecosystems and climate change." Phd thesis, 2011. http://hdl.handle.net/1885/150245.
Повний текст джерелаNogueira, Joana Filipa Garrido. "Freshwater biodiversity assessment in areas with and without protection." Master's thesis, 2019. http://hdl.handle.net/1822/65330.
Повний текст джерелаFreshwater ecosystems are essential to human well-being and are considered areas of high biodiversity. However, this biodiversity has been suffering severe declines due to the expansion of human activities. Protected areas are essential for biodiversity conservation and have proven to be successful in stopping species extirpation, when managed properly. Unfortunately, they are usually focused on terrestrial biodiversity, leaving many times freshwater ecosystems aside. The main goal of this study was to determine the influence that the Montesinho Natural Park (MNP), mainly designed to protect terrestrial biodiversity, has on freshwater biodiversity present in Mente, Rabaçal, Tuela and Sabor Rivers. Therefore, we sampled two aquatic faunal groups: fishes and invertebrates (bivalves and other macroinvertebrates) inside, in the periphery and outside the MNP. Biodiversity (richness, abundance, Shannon-Wiener diversity and Pielou’s evenness) and water quality (IBMWP, IASPT and %EPT) indices were calculated. It would be expected that results indicated better abiotic and biological conditions inside the park. However, this was not the case, with results showing that the protected area does not affect positively neither water quality nor the two faunal groups monitored. The macroinvertebrate communities and Margaritifera margaritifera abundance were not influenced by the protected area and only M. margaritifera length was significantly lower inside the MNP. For the fish communities, richness and abundance were significantly higher outside the protected area. Given these results, we conclude that MNP does not guarantee protection for the aquatic biodiversity and its ecosystems. This work highlights the view that protected areas need to be designed and managed for aquatic biodiversity if they intend to be successful in their conservation. Control of non-native species, reduction of point source pollution, regulation of fisheries and improvement of rivers connectivity are some of the most important actions that need to be taken by governmental, local population and stakeholders in order to achieve a proper protection of freshwater ecosystems and prevent the extirpation of species with conservation importance.
Os ecossistemas de água-doce são essenciais para o bem-estar humano, sendo consideradas áreas com grande biodiversidade. No entanto, esta tem sofrido uma diminuição enorme devido à expansão das atividades humanas. As áreas protegidas são essenciais para a conservação da biodiversidade e já provaram ser bem-sucedidas em travar a extirpação de espécies quando são bem geridas. Infelizmente, são maioritariamente focadas na biodiversidade terrestre, ignorando muitas vezes os ecossistemas de água-doce. O principal objetivo deste trabalho foi determinar a influência do Parque Natural de Montesinho (PNM), que foi projetado para proteger a fauna terrestre, na biodiversidade de água-doce presente nos Rios Mente, Rabaçal, Tuela e Sabor. Assim sendo, foram amostrados dois grupos faunísticos: peixes e invertebrados (bivalves e outros macroinvertebrados) dentro, na periferia e fora do PNM. Com estes dados foram calculados índices de diversidade (riqueza, abundância, diversidade de Shannon-Wiener e equitabilidade de Pielou) e índices de qualidade de água (IBMWP, IASPT e %EPT). Seria expectável que os resultados indicassem uma melhor condição abiótica e biológica dentro do parque. Contudo, este não foi o caso pois os resultados mostraram que a área protegida não afeta positivamente nem a qualidade de água nem nenhum dos dois grupos faunísticos monitorizado. As comunidades de macroinvertebrados e a abundância de Margaritifera margaritifera não foram influenciadas pela área protegida e apenas os comprimentos de M. margaritifera foram significativamente menores dentro do PNM. No que diz respeito às comunidades de peixes, a riqueza e a abundância foram significativamente maiores fora da área protegida. Assim sendo, concluímos que o PNM não garante a proteção de espécies aquáticas e dos seus ecossistemas. Este trabalho reforça a visão de que as áreas protegidas têm que ser desenhadas e geridas tendo também em conta a diversidade aquática se tencionam ser eficazes na sua proteção. O controlo de espécies nãonativas, a redução de fontes localizadas de poluição, a regulação das pescas e a melhoria da conectividade dos rios são algumas das medidas mais importantes a tomar pelo governo, pela população local e por outras partes interessadas de modo a alcançar uma proteção adequada dos ecossistemas de água-doce e impedir a extirpação de espécies com importância de conservação.
Mattocks, Steven R. "Ecological Consequences of Lost Anadromous Forage Fish in Freshwater Ecosystems." 2016. https://scholarworks.umass.edu/masters_theses_2/433.
Повний текст джерелаMCCLEARY, KATHRYN. "A comparative paleolimnological assessment of the influences of early Arctic population groups on freshwater ecosystems from southern Baffin Island, Nunavut." Thesis, 2011. http://hdl.handle.net/1974/6827.
Повний текст джерелаThesis (Master, Biology) -- Queen's University, 2011-10-04 15:52:18.29
"Regional scale risk assessment methodology using the relative risk model as a management tool for aquatic ecosystems in South Africa." Thesis, 2012. http://hdl.handle.net/10210/8096.
Повний текст джерелаDue to the excessive utilisation of the ecological services of surface aquatic ecosystems in South Africa, the integrity state of these systems continues to decline resulting in the loss of key ecosystem services. This trend suggests that the national requirements to maintain a sustainable balance between the use and protection of these systems are not being met. In an attempt to address this status quo, all stakeholders of these systems need to become more closely engaged in the social and institutional decision making processes to manage these systems. Management plans need to be integrated and take a wide range of conservation and use objectives for specific ecosystems into account. Furthermore, approaches need to allow for the assessment of multiple stressors that have synergistic effects, while the unique characteristics of the ecosystem taken into consideration. Risk assessments entail assigning magnitudes and probabilities to hazards or anthropogenic activities or natural catastrophes that have adverse effects m ecosystems. In these assessments the existence of a hazard and the related uncertainty of its effects results in the formulation of risk. An Ecological Risk Assessment is a structured approach that describes, explains and organises scientific facts, laws and relationships, thereby providing a sound basis to develop sufficient protection measures for the environment, which facilitates the development of utilisation strategies for the environment. A Regional Scale Risk assessment using the Relative Risk Model (RRM) is a form of Ecological Risk Assessment that is carried out on a spatial scale where considerations of multiple sources of multiple stressors affecting multiple endpoints are allowed. The use of the RRM also allows for the characteristics of the landscape that may affect the risk estimate to be considered. This study is based on a research hypothesis that the RRM is a suitable water resources management tool that can address the risk assessment of multiple stressors in South African freshwater environments. To test this hypothesis this study aims to contextualise the RRM methodology within the current water resources management practices in South Africa and demonstrate the applicability of RRM within the South African water resources management framework. The applicability of the RRM will be tested using two case study regions. The case studies are the Elands River and its associated ecosystems in the upper Crocodile River catchment in Mpumalanga and the entire catchment of the Umvoti River in KwaZulu-Natal
Horrigan, Nelli. "Neural network based decision support framework for the assessment and management of freshwater stream habitats." 2005. http://hdl.handle.net/2440/37736.
Повний текст джерелаThesis (Ph.D.)--School of Earth & Environmental Sciences, 2005.
Maseti, Pumza Penelope. "Biomonitoring in two contrasting catchments /." 2005. http://eprints.ru.ac.za/243/.
Повний текст джерелаMutch, Paul D. "Assessment of small scale tallgrass prairie restoration in an urban environment." 2007. http://hdl.handle.net/1993/2944.
Повний текст джерелаFebruary 2008
(8098112), Ben L. Gottesman. "Using Soundscapes to Measure Biodiversity, Habitat Condition, and Environmental Change in Aquatic Ecosystems." Thesis, 2019.
Знайти повний текст джерелаDewson, Zoë Spence. "Small stream ecosystems and irrigation : an ecological assessment of water abstraction impacts : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Ecology at Massey University, Palmerston North, New Zealand." 2007. http://hdl.handle.net/10179/1575.
Повний текст джерелаSmall streams are often used for small-scale water abstractions, but the effects of these water abstractions on the instream environment, invertebrate communities and ecosystem functioning of small permanent streams is poorly understood. This research extends current knowledge by surveying existing water abstractions and completing flow manipulation experiments in the field. Reduced discharge often decreases water velocity, water depth, and wetted channel width and can increase sedimentation, modify the thermal regime and alter water chemistry. In a survey of sites upstream and downstream of existing water abstractions, I found that downstream sites had higher densities of invertebrates, but fewer taxa sensitive to low water quality compared with upstream sites. There were greater differences in physicochemical characteristics such as velocity and conductivity and in invertebrate communities between upstream and downstream sites on streams where a larger proportion of total discharge was abstracted. Using before-after, control-impact (BACI) designed experiments, weirs and diversions were created to experimentally decrease discharge by over 85% in each ot three small streams, ranging from pristine to low water quality. The response of invertebrates to short-term (one-month) discharge reduction was to accumulate in the decreased available area, increasing local invertebrate density. After a year of reduced flow, the density of invertebrates and percentage of mayflies, stoneflies and caddisflies decreased at the pristine site, whereas only taxonomic richness decreased at the mildly polluted stream. Reduced discharge had no affect on the invertebrate community at the stream with the lowest water quality. Reduced discharge had little influence on leaf decomposition rates, but distances travelled by released coarse particulate organic matter (CPOM) increased with increasing discharge. The effects of reduced discharge on primary production were not consistent between streams. Overall, the severity (magnitude/duration) of flow reduction appeared to influence invertebrate responses to water abstraction although the outcomes of water abstraction were dependent on the invertebrate assemblage present in each stream.
Denault, Catherine. "Assessment of the likely impact of climate change on infrastructure and natural ecosystems of a small watershed in British Columbia : implications for hydraulic infrastructure design and stormwater management." Thesis, 2001. http://hdl.handle.net/2429/12024.
Повний текст джерелаHagström, Erika. "Utveckling av metod för att synliggöra och värdera ekosystemtjänster i öppen dagvattenhantering." Thesis, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-302162.
Повний текст джерелаNaturområden och grönytor levererar olika tjänster som människan är helt beroende av för sin överlevnad. Dessa tjänster kallas ekosystemtjänster och är exempelvis ren luft, rent vatten och pollinering av grödor. Närhet till naturen och grönområden har också stor betydelse för människans välbefinnande, till exempel genom att ha en stressdämpande effekt. Trots att vi är medvetna om värdena som naturen skapar, byggs grönytor i städer bort i takt med att de växer och förtätas. Täta städer innebär stora arealer hårdgjorda ytor vilket också resulterar i större volymer dagvatten då nederbörden inte kan infiltrera ner i marker och istället rinner av på ytan. Ledningarnas kapacitet riskerar att överskridas vid stora skyfall vilket kan orsaka stora problem med översvämningar. Problemet kommer dessutom förvärras i framtiden med de väntade klimatförändringarna. Ökande utmaningar med dagvattenhanteringen har resulterat i att öppna dagvattenlösningar började användas som komplement till ledningar under mark. Öppna dagvattenlösningar innebär att vattnet tas omhand på ett sätt som efterliknar naturens sätt att ta hand om nederbörd, och är en form av urbana ekosystem som, utöver att dämpa vattenflöden, kan tillhandahålla en rad andra ekosystemtjänster. Syftet med detta examensarbete var att skapa en metod för att integrera och värdera ekosystemtjänster i utformningen av öppen dagvattenhantering och därmed synliggöra ekosystemtjänsternas värden. Examensarbetet avgränsades till att utreda sju olika öppna dagvattenlösningar: gröna tak, infiltration på gräsytor, tillfällig uppdämning på översvämningsytor, svackdiken, naturliga diken och bäckar, dammar samt våtmarker. 12 ekosystemtjänster identifierades kunna erhållas från de öppna dagvattenlösningarna. Dessa var dricksvattenresurs, icke drickbart vatten, vattenrening, kolbindning och lagring, klimatreglering och luftrening, bullerreducering, flödesreglering, pollinering, livsmiljöer och biologisk mångfald, aktivitetsbaserade kulturella värden, estetiska värden samt resurs för forskning och utbildning. Ekosystemtjänsternas värden hos de olika dagvattenlösningarna bestämdes i en semikvantitativ enkätstudie där 16 personer fick värdera dagvattenlösningarnas kapacitet att bidra till de olika ekosystemtjänsterna. Värdena beror också till stor del på platsens förutsättningar och hur de utformas. Vilka faktorer som kan påverka värdet av ekosystemtjänsterna med avseende på dessa aspekter utreddes i en kvalitativ litteraturstudie. Resultatet från litteraturstudien samt enkätstudien utgjorde grunden för det icke platsanpassade värderingsverktyget som togs fram som det sista steget i examensarbetet. Verktyget utformades i Excel och består av tre steg där steg 1 syftar till att vikta ekosystemtjänsternas värden efter platsens förutsättningar, i steg 2 sker själva värderingen samt en eventuell anpassning till alternativ utformning och i steg 3 beräknas en faktor fram som är ett mått på ekosystemtjänsternas värden som fås från öppna dagvattenlösningar i förhållande till den totala arean. Syftet är att värderingsverktyget ska användas som ett komplement till en utredning om vilken dagvattenhantering som är lämpligast i ett projekt.
Oyeleke, Babawale Sowemimo. "Assessment of productivity and supply chain of aquaculture projects in Gauteng Province for sustainable operation." Diss., 2017. http://hdl.handle.net/10500/23118.
Повний текст джерелаAgriculture, Animal Health and Human Ecology
M. Sc. (Agriculture)
Ospan, Arman K. "A cumulative effect assessment using scenario analysis methodology to assess future Cowichan River Chinook and Coho salmon survival." Thesis, 2021. http://hdl.handle.net/1828/12939.
Повний текст джерелаGraduate