Rozprawy doktorskie: „Water diversion”

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Chen, Hui, i Peter F. Ffolliott. "South-to-North Water Diversion Project in China". Arizona-Nevada Academy of Science, 2008. http://hdl.handle.net/10150/296674.

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Pruneda, Erik Brian. "Use of stream response functions and stella software to determine impacts of replacing surface water diversions with groundwater pumping withdrawals on instream flows within the Bertrand Creek and Fishtrap Creek watersheds, Washington State, USA". Online access for everyone, 2007. http://www.dissertations.wsu.edu/Thesis/Fall2007/e_pruneda_121907.pdf.

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Khalil, Kamal. "Water surface profile modelling for Pinjarra flood diversion channel and economic evaluation". Thesis, Curtin University, 2007. http://hdl.handle.net/20.500.11937/2455.

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Shire of Murray has concerns regarding the negative impact that a 100 year flood could have on existing structures built before 1997. The increase cost in construction due to landfill has an adverse effect on development in Pinjarra. Feasibility of constructing a diversion channel at upstream of Murray River to attenuate the flood level from 1 in 100 year ARI to 1 in 50 year ARI, was investigated by Kiong (2003). The Murray River Water Surface Profile along three kilometres south of Greenlands Road was modelled. Flood damages on each flood occurrence were assessed and Average Annual Damage (AAD) was calculated. The AAD is used to estimate the monetary benefit against the construction cost of the diversion channel. Groundwater along Greenlands and Fauntleroy Drains was also modelled to determine the viable depth of the designed channel, as well as the analysis of backwater. The proposed channel is designed at different scenarios (invert level at breakout point, culvert or causeway design, and diversion channel variations). The benefit cost ratio of the proposed diversion channel is calculated. Other mitigation options are suggested including detention basins for structural measure, or building a new flood-proof township for non-structural measure.

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Khalil, Kamal. "Water surface profile modelling for Pinjarra flood diversion channel and economic evaluation". Curtin University of Technology, Department of Civil Engineering, 2007. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=17589.

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Shire of Murray has concerns regarding the negative impact that a 100 year flood could have on existing structures built before 1997. The increase cost in construction due to landfill has an adverse effect on development in Pinjarra. Feasibility of constructing a diversion channel at upstream of Murray River to attenuate the flood level from 1 in 100 year ARI to 1 in 50 year ARI, was investigated by Kiong (2003). The Murray River Water Surface Profile along three kilometres south of Greenlands Road was modelled. Flood damages on each flood occurrence were assessed and Average Annual Damage (AAD) was calculated. The AAD is used to estimate the monetary benefit against the construction cost of the diversion channel. Groundwater along Greenlands and Fauntleroy Drains was also modelled to determine the viable depth of the designed channel, as well as the analysis of backwater. The proposed channel is designed at different scenarios (invert level at breakout point, culvert or causeway design, and diversion channel variations). The benefit cost ratio of the proposed diversion channel is calculated. Other mitigation options are suggested including detention basins for structural measure, or building a new flood-proof township for non-structural measure.

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Zhu, Junlin. "Simulation and design of diversion and detention system for urban stormwater management". Thesis, Virginia Polytechnic Institute and State University, 1986. http://hdl.handle.net/10919/94495.

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Diversion of the first flush of storm runoff to a detention basin for pollutant removal is an efficient way to control nonpoint source pollutant in urban areas. This can be achieved by a diversion box and detention basin system. To numerically simulate the response of the system to a design rainfall event and the associated pollutant loadings for a given drainage area, a desk top model has been developed for"user-friendly"' application in personal computers. Hydrographs and pollutographs are generated at the inlet and outlet of the diversion box and the detention basin.These hydrographs and pollutographs are examined and the peak outflow and peak pollutant concentrations are compared with allowable outflow and pollutant concentration for urban stormwater quality and quantity management. This model is designed for both the analysis and design of the system.
M.S.

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Chan, Che-san Teresa, i 陳芷珊. "Water management in China: the quantitative and qualitative approaches in the eastern route of the south to northwater diversion project". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2013. http://hub.hku.hk/bib/B50702889.

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Turan, Kamil Hakan. "Development Of A Computer Program For Optimum Design Of Diversion Weirs". Master's thesis, METU, 2003. http://etd.lib.metu.edu.tr/upload/12605490/index.pdf.

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A diversion weir is a headwork facility built across a river to raise the water level and to divert water for various purposes, such as irrigation, hydropower generation, etc. Diversion weirs with sidewise intakes are widely used in plain rivers. They are composed of many structural components which are designed for different purposes. In this thesis, a Windows-based, visual, user friendly program named WINDWEIR was developed in Visual Basic.NET programming language for the optimum design of a diversion weir with sidewise intake. It determines the overall dimensions of each of the components of the diversion weir and the total cost of the whole structure. It also performs stability analysis. It is such a flexible computer program that a design engineer can assess various dimensions of the structure from viewpoints of safety and economy by performing quick successive test runs to achieve an optimum solution among various alternatives.

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Fockler, Matthew N. "Plumbing the Truckee : water, diversion and the creation of community along the Truckee River, Nevada /". abstract and full text PDF (free order & download UNR users only), 2007. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1448330.

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Thesis (M.S.)--University of Nevada, Reno, 2007.
"August, 2007." Includes bibliographical references (leaves 301-309). Online version available on the World Wide Web. Library also has microfilm. Ann Arbor, Mich. : ProQuest Information and Learning Company, [2007]. 1 microfilm reel ; 35 mm.

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Van, Heerden Morne Jandre. "Control of sediment diversion in run-of-river hydropower schemes". Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/71849.

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Thesis (MEng)--Stellenbosch University, 2012.
ENGLISH ABSTRACT: Sedimentation and the effects it has on turbine blades was the primary problem identified in run-of-river (RoR) hydropower schemes. Sedimentation in RoR hydropower schemes also increases trash rack blockage and reduces energy output in the long-term. Damage occurs to all underwater parts that come into contact with sediment. The main concern is sediment passing through the hydropower intake and causing turbine damage. The reason for the abrasion and cavitation of turbine blades is increased sediment loads in river channels. This problem can be overcome in two ways. The first is the use of existing lakes or reservoir storage upstream as natural sand traps, and the second is by investigating the three features associated with river bend diversion, which are: the optimum diversion location in a river bend to minimise the abstraction of sediment, the optimum diversion structure angle to limit coarse sediment diversion, and the sediment load diverted through the intake. The first objective of the research was investigated by construction of a physical model of a curved river channel to determine the location of the deepest scour forming on the outside of the bend. The second objective was to test the diversion orientation to maximize the local scour and thereby limiting sediment diversion at the intake. A third objective was to compare mathematical 2D model simulated scour results with the findings of the laboratory tests to evaluate the reliability of the numerical model predictions. Finally different diverted discharge ratios were tested with different intake setups in the physical model, to evaluate the sediment load diverted. . The first experiment in the curved laboratory channel was to predict where the deepest scour takes place without a diversion structure. This was then followed by placing a diversion structure at the maximum scour position, retrieved from experiment one, and by angling the structure with reference to the flow direction. The flow direction vector was placed as a tangent to the bend and orientated at angles of 0⁰, 30⁰, 45⁰ and 60⁰ into the bend direction. The optimum diversion location was found to be positioned on the outside of the bend, approximately 60⁰ into the channel bend. The final position of maximum scour in a 90⁰ bend corresponds with the Sediment Committee and the Chinese Hydraulic Engineering Societies (1992) prediction of 60⁰ into the bend. The optimal diversion had a 30⁰ angle to the flow direction, as this presented the most efficient and effective scouring in front of the model intake. Numerical simulations were performed with the CCHE 2D (hydrodynamics and sediment dynamics) modelling program. The numerical results were compared to the physical results to validate CCHE as a beneficial simulation tool. It was found that the numerical model predicted the scour depths at the intakes tested with an accuracy of 43.8%, which is within the accuracy range of the sediment transport equation used by the numerical model. The final experiment was the diversion of sediment with different intake level heights and discharges. It was evident from the results that low sediment diversion ratios were achieved with a diverted discharge ratio of 50% or less. The intake elevation highest above the channel bed diverted the least sediment. The interrelationship between Diverted Discharge Ratio (DDR), Diverted Froude number Ratio (DFrR) and Diverted Sediment load Ratio (SDR) was established in the study. It is recommended that RoR schemes have sand traps downstream of the diversion structures and that turbines are coated with HVOF to overcome the power loss arising due to the excessive erosion of hydro turbines.
AFRIKAANSE OPSOMMING: Sedimentasie en die invloed wat dit het op turbines was die primêre probleem geïdentifiseer in “run-of-river” (RoR) hidrokrag-skemas. Die sediment wat saam met die water uit ‟n rivier uitgekeer word beskadig die inlaatrooster en verlaag kragopwekking in die langtermyn. Skade word aangerig aan alle onderwatertoerusting en masjinerie wat aan sediment blootgestel word. Die grootste probleem tydens die uitkering van water is die growwe sediment wat daarmee deur die onttrekking inlaat gaan en turbineskade veroorsaak. Soos wat die sedimentlading in die rivier drasties toeneem, sal afslyting en kavitasie van turbinelemme meer gereeld voorkom. Dié probleem kan op twee maniere beperk word. Die een is die gebruik van bestaande opgaardamme stroomop, en die tweede is deur die ondersoek van drie kenmerke van rivierdraaie en uitkeringstrukture, bv. die optimale uitskurings posisie in 'n rivierdraai (sonder ŉ struktuur) om die diepste uitskuringposisie op die buitekant van die draai te bepaal, die optimale uitkeringsstruktuuroriëntasie wat maksimum uitskuring verseker en die sediment uitkering beperk, en die lading van sedimentonttrekking deur die inlaat. Die eerste doelwit van die navorsing is ondersoek deur ŉ fisiese model te bou van ŉ kronkelkanaal en te bepaal waar die diepste uitskring plaasvind op die buitekant van die draai. Die tweede doelwit van die studie was om die optimale uitkeringshoek te bepaal vir 'n uitkeringstruktuur sodat die uitskuring by die inlaat ŉ maksimum is om die uitkering van sediment te beperk. ŉ Derde doelwit was om die akkuraatheid van ŉ wiskundige model se uitskuring voorspelling te toets teen die waargenome laboratorium resultate. Die finale doelwit was om vir verskillende inlaatontwerpe, rivier- en uitkeervloeie die sedimentladings wat uitgekeer word te ondersoek. Die eerste eksperiment in die kronkelende kanaal was voorberei om die optimale uitskuring in die draai te bepaal. Dit is gevolg deur toetse met uitkeerstrukture by die maksimum uitskurings posisie te plaas en die hoek van die struktuur dan te verander met verwysing na die vloeirigting. Die vloeirigting vektor was as 'n raaklyn geplaas op die kanaal draai en georiënteer met hoeke: 0⁰, 30⁰, 45⁰ en 60⁰, in die rigting van die draai. Die optimale uitskurings posisie was aan die buiterand van die kanaal draai gevind, ongeveer 60⁰ in die draai in. Die maksimum uitskuur posisie van 'n 90⁰ kanaal draai stem ooreen met SC en CHES (1992) se resultaat van 60⁰ in die draai in. Daar was ook genoegsame bewyse dat 'n optimale uitkeerwerke oriëntasie van 30⁰ die doeltreffendste en effektiefste uitskuring sal gee. Numeriese simulasies is deur middel van 'n twee dimensionele wiskundige model CCHE 2D (hidro- en sedimentdinamika) uitgevoer. Die numeriese resultate was vergelyk met die laboratoriumresultate om die CCHE program te verifieer as 'n voordelige simulasie program. Daar is gevind dat die wiskundige model die uitskuurdieptes by die inlate met ŉ akkuraatheid van 43.8 % voorspel, wat binne die akkuraatheid is van die sedimentvervoervergelyking wat deur die numeriese model gebruik word. Die finale eksperiment was die uitkering van sediment met verskillende inlaathoogtes en uitkerings sedimentladings. Uit die toetse was dit duidelik dat 'n lae sediment uitkeerverhouding behaal kan word met 'n uitkeerverhouding van 50% en minder. Verdere waarnemings het ook gewys dat die inlaathoogte van die uitkeerstruktuur met die optimale resultate die hoogste bokant die rivierbedding was. Die verwantskap tussen die uitgekeerde deurstromingverhouding, die uitgekeerde Froude getal verhouding en die uitgekeerde sedimentlading is bepaal in die navorsing. Dit word aanbeveel dat sandvangkanale stroomaf van uitkeerwerke geplaas word en dat turbines met HVOF as bedekkingsmateriaal beskerm word om kragverliese as gevolg van buitensporige erosie van die turbines te voorkom.

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Khalil, Kamal A. "Water surface profile modelling for Pinjarra flood diversion channel and economic evaluation of assets a risk from flooding /". Full text available, 2007. http://adt.curtin.edu.au/theses/available/adt-WCU20080415.093754.

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11

Smith, Jansen A., Daniel A. Auerbach, Karl W. Flessa, Alexander S. Flecker i Gregory P. Dietl. "Fossil clam shells reveal unintended carbon cycling consequences of Colorado River management". ROYAL SOC, 2016. http://hdl.handle.net/10150/622496.

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Water management that alters riverine ecosystem processes has strongly influenced deltas and the people who depend on them, but a full accounting of the trade-offs is still emerging. Using palaeoecological data, we document a surprising biogeochemical consequence of water management in the Colorado River basin. Complete allocation and consumptive use of the river's flow has altered the downstream estuarine ecosystem, including the abundance and composition of the mollusc community, an important component in estuarine carbon cycling. In particular, population declines in the endemic Colorado delta clam, Mulinia coloradoensis, from 50-125 individuals m(-2) in the pre-dam era to three individualsm-2 today, have likely resulted in a reduction, on the order of 5900-15 000 tCyr(-1) (4.1-10.6 mol Cm-2 yr(-1)), in the net carbon emissions associated with molluscs. Although this reduction is large within the estuarine system, it is small in comparison with annual global carbon emissions. Nonetheless, this finding highlights the need for further research into the effects of dams, diversions and reservoirs on the biogeochemistry of deltas and estuaries worldwide, underscoring a present need for integrated water and carbon planning.

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Cordell, Dana. "Urine Diversion & Reuse in Australia : A homeless paradigm or sustainable solution for the future?" Thesis, Linköping University, Department of Water and Environmental Studies, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-8310.

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Diverting urine from faeces or mixed wastewater and reusing it to fertilize crops, is a traditional method used in Asia. It is also a contemporary approach to sustainable nutrient and water management in Scandinavia and other parts of Europe. Urine diversion and reuse is a proven socio-technical system that has significant potential benefits on both a local and global scale, such as recirculating scarce plant nutrients like phosphorus back to agriculture, reducing eutrophication of waterways and improving water and sanitation systems. This thesis explores the nature of these benefits in Australia and the global context and what barriers would need to be overcome if a urine diversion and reuse system were implemented in Australia to achieve significant environmental benefits. These questions are investigated through stakeholder interviews in Sweden, to identify the ‘lessons learnt’ from the Swedish experience with urine diversion and reuse, and, through interviews with relevant stakeholders in Australia to identify possible barriers and opportunities, costs and benefits, and roles and responsibilities in the Australian context. Findings from both the stakeholder interviews are triangulated with other sources of knowledge, such as the literature, personal communications and a qualitative assessment of costs and benefits.

This thesis found that while urine diversion is likely to benefit the Australia situation and warrants further research, these benefits are fragmented and spread across a range of discourses and separate institutions. Its acceptance and effective introduction into Australia might therefore be challenged by its lack of a single obvious organisational home. To overcome this and other identified challenges, several recommendations are made. For example, an Australian demonstration trial of urine diversion and reuse is recommended where clear drivers and opportunities exist, such as: in new developments adjacent to agricultural land; in regions where algal blooms are a critical problem and are predominantly caused by municipal sewage discharges; and where synergies with waterless urinals are being considered for water conservation value. This thesis does not promote urine diversion and reuse as the ‘silver bullet’ to Australia’s water and nutrient problems, however it does recommend that it be considered on an equal basis next to other possible options. For example, if reducing nutrient loads on receiving water bodies is a key objective, then a cost-effective analysis of urine diversion and reuse, compared to other options to reduce nutrient loads, could be undertaken, ensuring all relevant costs and benefits to the whole of society are included in the analysis.

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Llorens, del Pino Alba. "Diversion of water from a tailings dam : Spillway arrangement and spillway channel designed to be maintenance free for 1000 years". Thesis, KTH, Vattendragsteknik, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-208765.

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An elaboration on how to construct a spillway for closure for a large tailings pond completely enclosed by embankments, leading to a situation where construction in bedrock is not possible is presented with the following conclusion. A stepped spillway arrangement constructed with granite blocks will require of large blocks for being stable, and will require of filters that are not always considered functional in long-term perspective. It is presented an analysis of the overall stability of the structure proposed and of the stability of its individual blocks. In addition, it will be impossible to design a vegetated channel that remains stable, without silting and without erosion, over thousand years without maintenance.

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Rose, Teresa, i n/a. "AN INTERDISCIPLINARY STUDY INTO THE IMPACTS OF FLOW REGULATION ON AN UPLAND GRAVEL BED RIVERINE ENVIRONMENT: A TRIBUTARY CONFLUENCE IN THE SNOWY RIVER DOWNSTREAM OF JINDABYNE DAM, AUSTRALIA". University of Canberra. Cooperative Research Centre for Freshwater Ecology, 1999. http://erl.canberra.edu.au./public/adt-AUC20080917.153237.

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Inter-Basin-Water Transfers significantly reduce flow and sediment regimes to the downstream ecosystem effecting differential channel adjustment at various locations. It is not known how macroinvertebrates adjust to flow regulation, either spatially or temporally, because research is lacking into how morphological adjustment affects benthic habitat. Feedback mechanisms that initiate the adjustment process must first be identified, then the effect on benthic habitat becomes apparent, thus, providing a link to macroinvertebrate response. Since regulation there has been a 95% reduction in flow volume, a complete downward shift in both the flow duration and flood frequency curves and a 194% increase in flow constancy compared to the pre- dam period. Furthermore, Jindabyne Dam traps 99.9% of the total incoming sediment load. Upstream of the tributary the dominant river response was accommodation adjustment with subsequent contraction of the river channel. Associated feedback mechanisms were ?armouring? and vegetation encroachment. Downstream of the tributary response was more complex, with channel contraction through aggradation and specifically the formation of a tributary mouth bar and fan, mid channel lobate bar, transverse bar and in-channel bench. Associated feedback mechanisms were interactions between vegetation and sediment; channel morphology, flow and sediment distribution; and sediment distribution, flow and channel morphology. These processes have had site specific and reach scale impacts on benthic habitat. Macroinvertebrate response to flow regulation was habitat specific (riffle or edge) and seemed to correspond to either site, or reach scale morphological adjustment, whereas, flow constancy seemed to affect edge macroinvertebrates throughout both reaches. Spatially, macroinvertebrates have not adjusted to the post- dam flow regime and temporally, macroinvertebrates have not recovered 30 years after the closure of Jindabyne Dam. How physical processes change habitats and how these impact on a river?s ecology and at what scale, are important considerations in river management.

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Fink, Daniel Francis. "Effects of a pulsing hydroperiod on a created riparian river diversion wetland". Columbus, Ohio : Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1167401886.

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Karapinar, Burcu. "Role Of Hydrology, Sewage Effluent Diversion And Fish On Mass Balance Of Nutrients In A System Of Shallow Lakes Mogan And Eymir, Turkey". Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12606542/index.pdf.

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In this study, annual total phosphorus (TP) budget and dissolved inorganic nitrogen (DIN) load were constructed for Lakes Mogan and Eymir for the period of eight years from 1997 to 2004 and the period of ten years covering from 1993 to 1995 and 1997 to 2004, respectively. Lake Mogan experienced seasonal and interannual water level fluctuations. Low water level experienced in 2001 led to decrease in the in-lake TP amount whereas 2-fold increase in the in-lake DIN amount was recorded. Also, high hydraulic residence time resulted in high TP and DIN amount in the lake. Increase in hydraulic residence time was due to management of the lake level. It seems that this practice deteriorates the water quality of Lake Mogan. In Lake Eymir, sewage effluent diversion undertaken in 1995 resulted in 2-fold and 11-fold decrease in TP and DIN amounts in the lake, respectively. High biomass of carp and tench were halved through selective removal during 1998-1999. A 2.5-fold and 1.5 fold decrease in the in-lake TP and DIN amounts, respectively, were recorded after the biomanipulation. In low water level years, the in-lake TP increased and the in-lake DIN amounts were high despite the fact that TP and DIN loads via inflows were significantly low. Therefore, the results showed that the in-lake phosphorus and nitrogen amount were controlled by internal processes rather than external loading in the years with low water levels which coincided with the high hydraulic residence times.

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Vidal, Brenda. "On-site sanitation systems - An integrated assessment of treatment efficiency and sustainability". Licentiate thesis, Luleå tekniska universitet, Arkitektur och vatten, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-71120.

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Small on-site sanitation systems for wastewater collection and treatment are prevalent in suburban and rural areas in many countries. However, these systems often underperform, causing potential impact to the receiving waters and increasing the risks to public health, thus hindering the overall sustainability of the systems. Understanding the different sustainability dimensions and trade-offs between assessment indicators can support the planning of sustainable on-site sanitation systems for a specific context. The overall aim of this thesis was to evaluate the sustainability and function of on-site sanitation systems by defining a set of indicators to assess on-site sanitation options and estimating them for different scenarios, and by investigating the treatment efficiency of on-site facilities for domestic wastewater treatment in a field study. Particular attention was given to the removal of phosphorus (P) and indicator bacteria due to their relevance in terms of eutrophication risk and public-health concern. In a multi-criteria approach, twelve indicators were defined to assess nine on-site sanitation systems. A reference group representing stakeholders’ views assigned weights to express the relative importance of each indicator. The reference group assigned the highest weights to the indicators robustness, risk of pathogen discharge and nutrient removal. Assessing the robustness proved to be challenging, as there is a gap between how the sanitation systems are expected to perform based on their design, and how they actually perform in practice, mainly due to incorrect construction, operation and maintenance. The discriminating power of the indicators was calculated using the entropy method, which showed that the indicators energy recovery and capital cost had little impact in the final ranking of the alternatives. A sustainability ranking was obtained by using the method ELECTRE III. A scenario analysis based on different settings of interest based on socio-economic and geographical factors was done to evaluate the changes in the ranking of alternatives. Overall, the greywater–blackwater separation system ranked the highest in the baseline scenario and when nutrient-related indicators were important (Scenario 2), together with the urine diversion system. The sand filter and drain field were the most sustainable options when nutrient removal and recycling was not important (Scenario 1), and (in combination with chemical P-removal) when the indicators related to energy and climate change had the highest weights (Scenario 3). In terms of P-removal, chemical removal outranked the alkaline P-filter. In a field study, the effluent wastewater from twelve on-site wastewater treatment facilities with sand and alkaline P-filters was evaluated in terms of removal and discharge of organic content, total and dissolved phosphorus, and indicator bacteria (E. coli, total coliforms, intestinal enterococci and C.perfringens). The results showed that the investigated sand filters generally had low P-removal capacity and sometimes exceeded the criteria for excellent water quality set by the EU bathing water directive with regard to intestinal enterococci and E. coli. Only one sand filter of eight was confirmed to remove P according to the Swedish guidelines for areas with non-sensitive receiving waters with a tot-P effluent concentration below 3 mg L−1. This indicates that a downstream treatment step is needed to meet the guidelines regarding P discharge concentrations. Alkaline P-filters generally removed P efficiently. Despite high effluent pH, the collected data did not generally confirm a further reduction of the bacterial content of the wastewater in the P-filters, as had been previously hypothesized. However, effluent concentrations of indicator bacteria showed moderate positive correlations with effluent concentrations of P and organic matter, indicating the potential of the P-filters to serve as a polishing step also for bacteria.
Små lokala avloppssystem för insamling och rening av avloppsvatten är vanligt förekommande i omvandlings- och landsbygdsområden i många länder. Dessa system fungerar ofta sämre än förväntat vilket kan leda till effekter på recipienter, ökad risk för folkhälsan och begränsa systemens hållbarhet. En djupare förståelse för hållbarhetsdimensioner och avvägningar mellan olika indikatorer kan stödja planering och implementering av hållbara lokala avloppsystem för specifika sammanhang. Det övergripande syftet med denna uppsats var att utvärdera hållbarhet och funktion av enskilda avloppssystem. Detta utfördes genom att först definiera en uppsättning indikatorer för bedömning av ett antal enskilda avloppsalternativ och sedan utvärdera dem för olika scenarier. Vidare var syftet att undersöka några systems prestanda för rening av hushållsavloppsvatten i en fältstudie. Särskilt fokus lades på reduktion av fosfor (P) och indikatorbakterier på grund av deras relevans i relation till övergödningsrisk och folkhälsoperspektiv. I en multikriteriestudie definierades tolv indikatorer för att bedöma nio typer av enskilda avloppssystem. En referensgrupp som representerade olika intressenter viktade indikatorerna för att uttrycka den relativa betydelsen av varje indikator. Referensgruppen gav systemens robusthet, risk för utsläpp av patogener, och näringsreduktion störst vikt. Att bedöma robusthet var en utmaning i studien, eftersom det finns ett gap mellan hur systemen förväntas fungera, och hur de faktiskt fungerar i praktiken, mestadels på grund av felaktig konstruktion, drift och underhåll. Indikatorernas diskriminerande effekt räknades ut med entropimetoden, som visade att indikatorerna energiåtervinning och kapitalkostnad hade liten inverkan på alternativens slutgiltiga rangordning. En scenarioanalys genomfördes baserad på socioekonomiska och geografiska faktorer. En hållbarhetsrankning erhölls genom att använda ELECTRE III-metoden. Överlag rankades system som separerar gråvatten – svartvatten samt urinseparerande system högst i basfallsscenariot och när näringsrelaterade indikatorer var viktiga (scenario 2). Markbäddar och infiltrationsanläggningar var de mest hållbara alternativen när rening och återvinning av näringsämnen inte var viktigt (scenario 1) och (i kombination med kemisk P-rening) när indikatorer relaterade till energi och klimatförändringar viktades högst (scenario 3). När det gäller P-rening, gav system med kemisk rening ett bättre utfall än de med alkaliska P-filter. I en fältstudie utvärderades tolv enskilda avloppsanläggningar med markbaserade system och alkaliska P-filter med avseende på rening och utsläpp av organiskt innehåll, totalt och löst P och indikatorbakterier (E.coli, totala koliformer, intestinala enterokocker och C.perfringens). Resultaten visade att de markbaserade systemen generellt hade låg P-reningskapacitet och ofta överskreds kriterierna för utmärkt vattenkvalitet enligt EUs badvattendirektiv avseende intestinala enterokocker och C. perfringens. Endast ett markbaserat system av åtta uppvisade en P-rening som låg under de svenska riktlinjerna för områden med normal skyddsnivå, med en utsläppskoncentration på under 3 mg L-1 tot-P. Detta indikerade att markbäddar behöver nedströms placerade reningssteg för att uppfylla nuvarande riktlinjer för utsläpp av P. Alkaliska P-filter avskilde generellt P effektivt. Trots högt pH-värde kunde ingen ytterligare minskning av bakterieinnehåll i avloppsvattnet från P-filtren påvisas statistiskt. Utsläppen av indikatorbakterier uppvisade emellertid måttliga positiva korrelationer med utsläpp av P och organiskt material, vilket visar på en viss potential att P-filtren kan fungera som ett ytterligare poleringssteg även för bakterier.

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Khabbaz, Saberi Hamid. "Hydraulic characteristics and performance of stormwater pollutant trap respect to weir's height, flow gradients, pipe diameters and pollutant capture". Thesis, Curtin University, 2009. http://hdl.handle.net/20.500.11937/2143.

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The main focus of urban stormwater runoff disposal has traditionally been to provide structurally-sound drainage systems to carry runoff from many different surfaces without considering water quality at outfall. This has contributed to the decline of water quality in rivers and lakes and other receiving bodies. According to Lord (1987), "stormwater management is primarily concerned with limiting future flood damages and environmental impacts due to development, where as flood control aims at reducing the extent of flooding that occurs under current conditions". Recent developments in stormwater pollutant trap (SPTs), which are generally end-of-the-line devices designed to capture and store gross pollutants, for subsequent removal and disposal.During the last few decades, use of SPTs as a source of collecting and removing pollutants from stormwater (which carries many different types of chemicals and nonchemical pollutants that contaminates our rivers, lakes and other receiving bodies) has increased considerably. Wide-ranging efforts and attempts have been made in both academic and industrial research to improve the quality of stormwater by improving the use of gross pollutant traps (GPTs – known as hydrodynamic separators) by utilising and improving available experimental and modelling techniques. The use of vortex phenomena has always been a challenging problem and available data is rare and complicated in the literature. This research focuses on detailed investigation by experimental means. The generated vortex in this experiment is created in a cylindrical chamber above the level of a cylindrical screening basket. In addition, the research analyses the processes involved in this separation technique.One scale model of a Versa Trap (Type A) was experimentally analysed to investigate and establish the relationship between headloss and flow rate and hydraulic characteristics of a weir in a diversion weir pit. The Versa trap Type A storm pollutant traps are usually used as off-line traps in city and urban areas to capture and store debris – especially those which are captured from surfaces such as rooftops, paved streets, highways, parking lots, lawns, and paved and gravelled roads (Allison et al., 1998). The Versa Trap Type A utilises an upstream diversion weir pit to divert the design treatment flow (DTF) into the treatment chamber. Treated flow returns to the diversion pit downstream of the weir, where it re-enters the drainage system. Peak flow in excess of the DTF bypasses the SPT over the weir into the pipeline downstream.It has been demonstrated that the aggregate of all flows of three months average recurrence interval (ARI) and less represented the majority (up to 97.5%) of the total flow generated by a stormwater drainage catchment (Works, 2006). There is some conjecture as to the veracity of the ‘first flush’ theory, which holds that most of the pollutants in the catchments are transported during the first flush of the storm event (Lee et al., 2007). However, it is generally accepted that SPTs should be sized so as to treat only a portion of the peak flow, with excess flows bypassing the trap. The three month ARI peak flow is commonly taken as appropriate for establishing the minimum DTF required of the SPT.The measurement of headloss across a scale model of a VT Type A storm pollutant trap at a range of flow rates through the SPT, provide data from which a mathematical relationship between flow rate and the headloss cab be established for the device.The resultant relationship then can be used in another part of the experiment to establish the hydraulic characteristics of a weir across a cylindrical chamber, as used for the upstream diversion weir pit in conjunction with the Type A VT range of SPTs. By varying the weir height in a scale model of a diversion weir pit and measuring the flow rates associated with headlosses determined from the previously established relationship, the relationship between weir height and diverted flow can be established. This allows the designer to specify the weir height required to divert the flow rate associated with a specific peak flow or treatment flow of SPT design.Two main characteristics which determine the performance of a gross pollutant trap are trapping efficiency and required maintenance. The trapping efficiency is defined as the portion of the total mass of gross pollutant transported by stormwater that is retained by the trap. A low trapping efficiency means that gross pollutants pass through the trap and reach downstream waters. A poorly-maintained trap will be inefficient at trapping pollutants and is also a potential source of pollutants as trapped materials break down.The experiment parts of this project were tested at Curtin University of Technology’s Hydraulic Laboratory. To replicate typical in-situ conditions, the VT Type A was tested for 0, 22, 33, 44, 55, 66 and 77% simulated blocked screen conditions for trapping efficiency. Data analysis has demonstrated that the headloss increases in proportion to flow rates and screen blockage condition. The results were scaled up to provide data on the full range of unit sizes. This research describes the testing and scaling methodologies in detail, with graphical representation of headloss and other hydraulic parameters at various conditions. The study’s findings have capabilities to optimise any other types of stormwater treatment systems. These types of traps’ are used in commercial and residential environment.This experiment is in continuation of the experiment which was conducted by Muhammad Ismail on industrial gross pollutant traps using double basket to trap the debris for industrial application.Also another good reference for pollutant build up and wash off modelling of impervious surfaces in Perth area, is done by Saadat Ashraf in his PhD thesis. For more information refer to references.

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Gorbach, Kathleen R. "Benthic Community Structure Response to Flow Dynamics in Tropical Island and Temperate Continental Streams". University of Dayton / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1354226302.

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Rich, Kyle. "Bridging Troubled Waters: Examining Culture in the Canadian Red Cross' Swimming and Water Safety Program". Thèse, Université d'Ottawa / University of Ottawa, 2013. http://hdl.handle.net/10393/24278.

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The Canadian Red Cross (CRC) offers its Swimming and Water Safety Program throughout Canada. The program is delivered by over 35 000 active instructors to over one million participants every year. The research in this thesis is part of a collaborative, interdisciplinary project in partnership with the CRC that examined ways to improve programming for cultural and ethnic minority populations. The thesis is written in the stand alone paper format. The first paper evaluates the program’s content, through a critical whiteness lens, to identify obstacles to offering effective programming to people of diverse cultural and ethnic backgrounds. Based on these findings, I created and piloted a cultural safety training module for program instructors. The second paper then evaluates the effectiveness of this training module to provide recommendations for the CRC to optimize its management of diversity within its organization and aquatics facilities across the country. Collectively, this thesis bridges both understandings of Eurocanadian and whiteness discourses as well as critical whiteness and organizational theories to more holistically understand processes of inclusion, exclusion, accommodation, and the management of diversity in the context of a nation-wide Canadian sport and recreation program.

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Whittenberger, Jessica. "Eukaryote diversity in Chicago area water samples". Connect to resource, 2007. http://hdl.handle.net/1811/26597.

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Thesis (Honors)--Ohio State University, 2007.
Title from first page of PDF file. Document formatted into pages: contains 30 p.; also includes graphics. Includes bibliographical references (p. 28-30). Available online via Ohio State University's Knowledge Bank.

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Barakoti, Sonia. "Diversity Analysis of Water Systems in the US". University of Toledo / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=toledo152545897931429.

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Roblin, Rachel. "Water Quality Modeling of Freshwater Diversions in the Pontchartrain Estuary". ScholarWorks@UNO, 2008. http://scholarworks.uno.edu/td/693.

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A 1-D tidal, salinity and water quality model that analyzes the general effects freshwater diversions have on the water quality of the Pontchartrain Estuary over a 17-year period is presented here. Using the modeled live algae concentrations in conjunction with the algal bloom probability model results produces an accurate prediction of algal bloom occurrences between 1990 and 2006. The model predicts that the addition of freshwater diversions into Maurepas swamp and increases to flow in the Bonnet Carré Spillway may cause more intense and frequent algal blooms to occur around the Pontchartrain Estuary. The model also predicts that high nutrient input events that occur earlier in the year (January/February) will not likely have algal blooms associated with them. When nutrient input events (even small events) occur in the late spring or early summer, algal blooms have a high probability of occurring when the salinity, temperature and light levels are sufficient.

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Neupane, Jeevan. "Water Quality Modeling of Freshwater Diversions in the Barataria Basin". ScholarWorks@UNO, 2010. http://scholarworks.uno.edu/td/1255.

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A 1-D tidal, salinity and water quality model that analyzes the impacts of freshwater diversions with median and high flow on the water level, salinity and nutrient concentration of the Barataria Basin over a 2 period is presented here. The model predicts that the salinity of Lower Barataria decreases with the introduction of freshwater diversions. The model also predicts that nutrient concentration increases in Barataria Basin and decreases in Northern Gulf of Mexico with the introduction of diversions. The model shows the impact of freshwater diversions on water level except in the neighborhood of the diversion sites are small.

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Lawler, Stephanie Nichole. "Characterization of Bacterial Diversity in Cold-Water Anthothelidae Corals". Scholar Commons, 2016. http://scholarcommons.usf.edu/etd/6295.

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Cold-water corals, similar to tropical corals, contain a diverse and complex microbial landscape. Comprised of vital microscopic organisms (i.e. bacteria, viruses, archaea), the coral microbiome is a driving factor in the proliferation and survival of the coral host. Bacteria provide essential biological functions within coral holobionts, facilitating increased nutrient utilization and production of antimicrobial compounds. To date, few cold-water octocoral species have been analyzed to explore the diversity and abundance of their microbial associates. For this study, 23 samples of the family Anthothelidae were collected from Norfolk (n = 12) and Baltimore Canyons (n = 11) from the western Atlantic in August 2012 and May 2013. Genetic testing found that these samples comprised two Anthothela species (Anthothela grandiflora and Anthothela sp.) and a new genus. DNA was extracted and sequenced with primers targeting the V4-V5 variable region of the 16S rRNA gene using 454 pyrosequencing with GS FLX Titanium chemistry. Results demonstrated that the host genus was the primary driver of bacterial composition. The new coral genus, dominated by Alteromonadales and Pirellulales, had much higher species richness and a distinct bacterial community compared to Anthothela samples. Anthothela species had very similar bacterial communities, dominated by Oceanospirillales and Spirochaetes. Core bacterial diversity present across 90% of the Anthothela samples revealed genus-level conservation. This core included unclassified Oceanospirillales, Kiloniellales, Campylobacterales, and Spirochaeta; the functional abilities of which contribute to a nearly complete nitrogen cycle. Dominant bacterial members of the new coral genus also had functional capabilities in nitrogen cycling. Overall, many of the bacterial associates identified in this study have the potential to contribute to the acquisition and cycling of nutrients within the coral holobiont.

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Kupel, Douglas E. (Douglas Edward) 1956. "Diversity through adversity : Tucson Basin water control since 1854". Thesis, The University of Arizona, 1986. http://hdl.handle.net/10150/191882.

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This thesis considers water utilization in the Tucson Basin, Arizona. The study concentrates on the American period of Tucson history from 1854 to 1940, although it includes a chapter examining the physical and cultural setting of the area prior to 1854 and a concluding chapter covering events since 1940. The thesis links Western water development to broad patterns in American history, contrasting earlier treatments which characterize the region as a unique entity due to its arid environment. If the West is different from the humid East, the thesis contends, the reason for the West's distinction occurred not because of aridity but in spite of it. Development patterns in the West are actually quite similar to those in the eastern United States, due mainly to the transplantation of an agrarian myth to the West achieved through technological advances. The result is a society apart from its environment rather than within it.

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O'Connell, Davidson Julia. "The employment relation : diversity and degradation in the privatised water industry". Thesis, University of Bristol, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.294386.

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Nigro, Lisa M. "Distribution and Diversity of Bacterial Chemolithotrophs in Marine and Freshwater Sediments". Fogler Library, University of Maine, 2006. http://www.library.umaine.edu/theses/pdf/NigroLM2006.pdf.

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Garrido, Molina Laura. "Molecular characterization of microbial diversity in wastewater treatment and reuse". Doctoral thesis, Universitat Autònoma de Barcelona, 2012. http://hdl.handle.net/10803/96237.

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La generació d’aigua residual és una conseqüència inevitable de les activitats humanes. Aquestes activitats modifiquen les característiques de les aigües de consum, contaminant-les i invalidant la seva posterior aplicació per altres usos. Abocar aquestes aigües sense depurar ocasiona danys, a vegades irreversibles, al medi ambient. D’altra banda, l’abocament d’aigües no depurades suposa riscos per la salut pública. Per aquesta raó, la depuració de les aigües residuals esdevé una necessitat important a la nostra societat. Les estacions depuradores d’aigües residuals (EDARs) constitueixen un dels processos biotecnològics més importants utilitzats arreu del món per depurar aigües residuals municipals i industrials. Des d’un punt de vista biològic, els microorganismes juguen un paper important en la depuració de les aigües residuals ja que són els principals responsables de l’eliminació de la matèria orgànica i dels nutrients d’aquestes aigües. D’altra banda, la reutilització de l’aigua s’està convertint en un aspecte cada vegada més important de la gestió sostenible dels recursos hídrics. En aquesta tesi s’ha estudiat la composició de les comunitats microbianes en diferents ambients relacionats amb la depuració d’aigües residuals i la seva reutilització. Per un costat, s’han estudiat i comparat les comunitats microbianes trobades en processos convencionals de depuració amb dos sistemes atípics de depuració d’aigua residual (un fang activat provinent d’una EDAR que processa aigua de mar i uns aiguamolls construïts). Per un altre, s’han determinat les diferències en el perfil microbià d’una aigua depurada versus una aigua dolça natural, amb la intenció de trobar un indicador alternatiu de qualitat de l’aigua. Finalment, s’ha analitzat la població microbiana associada amb els problemes derivats de la reutilització d’aigua. Les mostres del fang activat marí van ser analitzades utilitzant una aproximació completa per l’anàlisi de rRNA (electroforesi en gel de gradient desnaturalitzant, genoteca i hibridació in situ), obtenint-se una imatge de la composició de la comunitat completament diferent a la d’un fang activat convencional, amb la particularitat que es va trobar una presència molt baixa del grup Betaproteobacteria. A més, la detecció del gen funcional amoA va corroborar la presencia d’oxidadors d’amoni, que probablement eren de generes diferents als descrits en la literatura. Per un altra banda, les comunitats microbianes trobades en aiguamolls construïts experimentals pertanyien a espècies relacionades amb l’eliminació de matèria orgànica. L’estudi dels perfils d’aquestes comunitats va permetre determinar l’efecte del tipus de planta, el disseny hidràulic i la càrrega de matèria orgànica d’aquests sistemes en la seva composició. Comparant els nostres sistemes atípics de depuració amb els sistemes convencionals, es va poder concloure que cada sistema té la seva comunitat microbiana específica, adaptada a les seves condicions ambientals, duent a terme les mateixes funcions però amb diferents grups implicats. Tanmateix, l’examen dels perfils de diversitat microbiana d’aigües depurades provinents de EDARs i la seva comparació amb els perfils d’aigües naturals no contaminades mostrava que els efluents de depuradora tenen una empremta comú, que difereix de la d’una aigua natural. Segons això, tenint en compte els grups taxonòmics trobats més abundants en aquest tipus d’aigües, proposem l’ús de la ratio Bacteroidetes, Gammaproteobacteria i Nitrospira / Betaproteobacteria com a indicador alternatiu de qualitat ecològica de l’aigua. Pel que fa a la reutilització d’aigües, es va estudiar un exemple d’un problema de formació de biofilms derivat de l’ús d’aigua regenerada en un sistema de reg per goteig. En aquests biofilms la comunitat microbiana estava principalment composada per microorganismes termòfils i esporulats, la qual cosa suggereix que les altes temperatures dins de la infrastructura de reg van seleccionar aquestes poblacions. Per tant, sembla ser que les condicions en el sistema de reg poden ser més importants que la composició de la pròpia aigua regenerada.
Wastewater generation is an inevitable consequence of human activities. These activities modify the characteristics of the original waters, contaminating them and invalidating subsequent application for other uses. Dumping of raw sewage causes damage, sometimes irreversible, to the environment. On the other hand, the discharge of untreated sewage poses risks to public health. Thus, wastewater treatment becomes an important need in our society. Wastewater treatment plants constitute one of the most important biotechnological processes used worldwide to treat municipal and industrial sewage. From a biological point of view, microorganisms play an important role in wastewater treatment since they are the main responsible of the remove of organic matter and nutrients from this sewage. Furthermore, water reuse is becoming increasingly important as a component of sustainable management of water resources. In this thesis we investigated the composition of microbial communities in different environments related to wastewater treatment and reuse. First, we studied and compared the microbial communities found in conventional processes with two atypical treatment systems (activated sludge from a seawater-processing EDAR and constructed wetlands). On the other hand, we determined how different was the microbial profile of a treated wastewater versus a natural freshwater, and tried to find out an alternative indicator of water quality. Finally, we examined the microbial population associated with the problems arising from water reuse. Samples of a marine activated sludge were analyzed by using the full-cycle rRNA approach (denaturing gradient gel electrophoresis, clone libraries and in situ hybridization), obtaining a picture of the composition of the community completely different from a conventional activated sludge, with particularly a low presence of Betaproteobacteria. In addition, detection of the functional gene amoA corroborated the presence of ammonia oxidizers, corresponding probably to different genera from those described in the literature. On the other hand, the microbial communities found in experimental constructed wetlands belonged to species related with organic matter removal. The study of the profiles of these microbial communities allowed determining the effect of the type of plant, hydraulic design and organic matter load of these systems in their composition. Comparing our atypical treatment systems with conventional ones, we can conclude that each system has its specific microbial community, adapted to its environmental conditions, with the same functions being carried out by different groups. Besides, examination of microbial diversity profiles of treated wastewater from different EDARs and comparison with natural non-contaminated water showed that sewage effluents have a common fingerprint, which differs from natural water. Thus, taking into account the most abundant groups found in these types of waters, we proposed the use of the Bacteroidetes, Gammaproteobacteria and Nitrospira / Betaproteobacteria ratio as an alternative indicator of ecological water quality. Concerning water reuse, we focused on an example of a biofouling problem derived from the use of reclaimed water in a drip irrigation system. In these biofilms the microbial community was mainly composed of thermophilic and sporulated microorganisms, suggesting that high temperatures within the irrigation infrastructure selected these populations. Thus, it seemed that the conditions in the system may be more important than the composition of reclaimed water itself.

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MacRae, Sarah Catherine. "The diversity and structure of Escherichia coli populations in fresh water environments". Diss., University of Pretoria, 2013. http://hdl.handle.net/2263/79721.

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Escherichia coli is a well known commensal inhabitant of the gastrointestinal tract of both humans and animals and a highly diverse species. The physiology, biochemistry and genetics of E. coli have been studied extensively over many decades. However, these studies have focussed predominately on the pathogenic and commensal isolates. It has been described that E. coli typically exists in two environments, the primary environment being the gastrointestinal tract of the host and the secondary environment being that environment outside of the host (water, soil and sediments). Upon introduction into the environment outside of the host, the numbers of E. coli steadily decline. Generally, where E. coli is present in the external environment and where its numbers are maintained it is due to a constant direct faecal input from the host. This short lifespan in the environment outside of the host forms the basis for the use of E. coli as an indicator organism for faecal contamination in water systems. In contrast, multiple studies have shown that some E. coli strains have the ability to survive and persist in the external environment in the absence of faecal input from the host. With a large pan-genome and the possibility of horizontal gene transfer (HGT) of desirable traits, E. coli have the potential to adapt to a variety of different niches overcoming drastic changes in conditions in its new environment. In addition, adaptation to the secondary environment is facilitated by the presence of soils and sediments, where in an aquatic environment they provide a source of nutrients and protection from the drastic change in conditions. Here, E. coli has the ability to occupy a new niche and become naturalised within an aquatic environment. The aim of this masters project was to examine and characterise the diversity of E. coli isolates collected from two South African freshwater environments namely, the Roodeplaat and Rietvlei Dams, Pretoria. Specific research questions addressed in this study include: (1) are their unique and genetically differentiated sub-populations within the aquatic environments sample? (2) Is there a link between the unique sub-populations and their sample site? (3) Finally, what is the relationship between sub-populations in terms of gene flow and population structure? Understanding E. coli’s population structure and ecology may shed some light on its evolution and potential to adapt to new environments. Following phylogrouping, AFLP and phylogenetic analysis of the rpoS and uidA genes, the results indicated that the population was highly diverse with the majority of strains grouping together with the sewage isolates. Furthermore, population structure analyses concentrating on gene flow and genetic differentiation revealed that possible environmental groups exist within the population. In particular, two groups of E. coli isolates associated with aquatic plants showed restricted gene flow and definite genetic differentiation. These two groups can also be observed in the rpoS and uidA phylogenetic analyses where they consistently group together in the absence of sewage isolates. These findings demonstrate that some E. coli are not only able to survive outside of their host but have undergone some level of niche separation within the secondary environment. These results raise important questions into the accuracy of using E. coli as an indicator organism. In the long term, this study may aid in understanding the population dynamics of E. coli and the implications of environmental strains on using E. coli in assessing water quality.
Dissertation (MSc)--University of Pretoria, 2013.
NRF
Microbiology and Plant Pathology
MSc
Unrestricted

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Zhang, Rui. "Bacterioplankton in Hong Kong waters : diversity, dynamics, and mortality /". View abstract or full-text, 2007. http://library.ust.hk/cgi/db/thesis.pl?BIOL%202007%20ZHANGR.

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Garrick, Dustin E. "Explaining Institutional Diversity in Emerging Markets for Environmental Flows: A Transaction Costs Approach to Comparative Policy Evaluation in the Columbia Basin". Diss., The University of Arizona, 2010. http://hdl.handle.net/10150/195852.

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Chivukula, Vasanta Lakshmi. "Commensal fecal bacteria : population biology, diversity, and usefulness as indicator organisms in reclaimed water". [Tampa, Fla] : University of South Florida, 2005. http://purl.fcla.edu/usf/dc/et/SFE0001334.

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Grossiord, Charlotte. "Impact of tree species diversity on water and carbon relations in European forests". Thesis, Université de Lorraine, 2014. http://www.theses.fr/2014LORR0155/document.

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La biodiversité favorise un grand nombre de fonctions et services écosystémiques des écosystèmes forestiers tels que la production de bois ou la résistance aux attaques d’insectes et aux maladies. Cependant l’impact de la diversité sur l’acquisition et l’utilisation de l’eau et du carbone reste largement méconnu dans ces écosystèmes. De plus, dans le contexte actuel de changement climatique, l’influence de la diversité sur la réponse des écosystèmes forestiers à des événements climatiques extrêmes tels que la sécheresse reste à étudier. L’objectif de ce travail est donc de déterminer l’impact de la diversité en espèces d’arbre sur d’importantes fonctions du cycle de l’eau et du carbone telles que la transpiration, la composition isotopique du carbone ou la profondeur d’extraction de l’eau à l’échelle de l’arbre et de l’écosystème sous des conditions contrastées dedisponibilité en eau du sol. Ce travail a été réalisé dans le cadre du projet FunDivEUROPE sur un réseau de parcelles forestières ainsi que dans des plantations expérimentales le long d’un gradient Nord-Sud en Europe afin de couvrir une importante gamme de conditions climatiques. Nos travaux ont montré une importante variabilité de la réponse à la diversité à l’échelle de l’arbre et de l’écosystème en termes de relations hydriques et carbonées à travers l’Europe. La diversité en espèces ne semble pas influencer les relations hydriques et carbonées des espèces et des écosystèmes forestiers dans des conditions non limitantes de disponibilité en eau. Cependant, un fort effet de la diversité a été observé en conditions de sécheresse pour certains types forestiers. A partir de ces résultats, je discute des mécanismes d’interaction entre espèces qui peuvent expliquer les effets observés. Nos données ont montré que l’influence de la diversité en espèces est fortement dépendante du contexte et peut êtremodifiée par les conditions environnementales locales et les conditions climatiques. En terme de gestion forestière, je suggère que pour certaines régions en Europe, promouvoir la diversité en espèces ainsi que contrôler la densité des parcelles doit être recommandé afin d’adapter les écosystèmes forestiers aux futures conditions climatiques
Biodiversity is known to support and boost a wide range of forest ecosystem functions and services like productivity and resistance against insect pests and diseases. However, whether tree species diversity also promotes water and carbon acquisition and use in forest ecosystems is still unclear. Furthermore, in the current context of global warming, information on how tree species diversity can influence the response of forest ecosystems to extreme climatic events such as drought are urgently needed. In this framework, the objective of my PhD thesis was to determine how tree species diversity influences important functions of the water and carbon cycle including transpiration, carbon isotope composition and water extraction depth at the tree- and ecosystem-Scale under contrasting soil water conditions. My work was conducted within the FunDivEUROPE project in a network of permanent forest stands and tree plantations across a North-South gradient in Europecovering a wide range of climatic conditions. I found considerable variability among species or forest types in the response of transpiration and carbon isotope composition at the tree- and ecosystem-Scale across Europe. Species diversity did not affect the water and carbon relations of tree species and forest ecosystems under non-Limiting soil water conditions. However, a strong effect of species diversity was observed under drought conditions in some forest types. Based on these data, I discuss the potential mechanisms of species interactions that may explain the observed patterns. I also point out that the influence of species diversity is highly context-Dependent, and changes with local environmental and climatic conditions. In terms of forest management applications, I suggest that, at least in some regions, controlling for tree species diversity along with stand density and total basal area could be recommended to help forests adapt to drier conditions

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Al-Saffar, Dina A. H. "SIMO/MIMO body-centric space-time diversity over software-defined radio". Thesis, Loughborough University, 2018. https://dspace.lboro.ac.uk/2134/32153.

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This thesis is germane to body-centric communication measurements and analyses at different frequency bands. It presents measurements and analyses of the radio channels for humans. This research contains a novel and comprehensive study of body-centric single input multiple output (SIMO) diversity. This has included the analyses of diversity techniques with off-body communications in different settings within indoor environments. The objectives in this research are; investigating the benefits of using multiple antennas for off-body and on-body channels and studying the performance of diversity antennas for off-body in different environments with both genders. A further novel aspect of this thesis has been concerned with off-body channel characteristics using software defined radio (SDR) and LabVIEW using different modulation schemes for measurements and analyses. This method combines processing and control in software, paired with SDR for the over the air interface. The combination of SDR and LabVIEW is shown to provide a platform to facilitate experiments in the presence of humans that is useful for prototyping different types of radio channels. This method also gives a new aspect for a novel treatment of a 2x2 body-centric multiple input multiple output (MIMO) system. It is shown how the difficulties associated with implementing MIMO systems can be overcome by using SDR combined with LabVIEW. Studying the effects of water in the body-centric communication channels are also a new area of research presented here. This work has shown how water encapsulated within Polyacrylamide gel can be exploited as a cheap and available material to enhance the performance of on-body antennas. It is shown that water gives 1–3dB enhancements from the measurements of SIMO and MIMO systems with the human presence.

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Wilson, Alan Elliott. "Cyanobacteria-Grazer Interactions: Consequences of toxicity, morphology, and genetic diversity". Diss., Available online, Georgia Institute of Technology, 2006, 2006. http://etd.gatech.edu/theses/available/etd-04072006-125946/.

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Thesis (Ph. D.)--Biology, Georgia Institute of Technology, 2006.
Klausmeier, Christopher, Committee Member ; Montoya, Joseph, Committee Member ; Snell, Terry, Committee Member ; Sarnelle, Orlando, Committee Member ; Hay, Mark, Committee Chair.

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Schindler, Markus. "Effects of litter diversity, leaf quality and water chemistry on litter decomposition in streams /". Zürich : ETH, 2006. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=16789.

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Huang, Tieshi. "Diversity and transport of bacteria and viruses in soils following irrigation with recycled water". Thesis, University of Hawaii at Manoa, 2003. http://hdl.handle.net/10125/7033.

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Field and laboratory analyses were conducted to study bacteria and virus transport and diversity in surface soils following irrigation with recycled water. Field test plots were irrigated with R-1 (oxidized, filtered, disinfected) water and tap water, and pan lysimeters were used to collect leachate water samples. R-1, R-2 (oxidized, disinfected), R-3 (oxidized only) and tap water were applied to soil columns. Fecal coliform and coliphage were only found in the leachate from the R-3 soil column. Polymerase chain reaction denaturing gradient gel electrophoresis analysis (PCR-DGGE) of 165 rRNA genes was used to analyze the bacterial population in leachate and soil samples from different depths. The R-1 field test plot had a more diversified bacterial community than a tap water control plot. Surface soils from field test plots had more bacteria species than that of bottom soils. Different DGGE banding profiles were found at different depths in R-1, R-2 and R-3 effluent soil columns. UV dosage did have some effect on soil microbial diversity.
ix, 42 leaves

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Jonavičienė, Kristina. "Genetic diversity of Phleum spp. and identification of genes involved in water stress response". Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2012. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2011~D_20120508_105857-18465.

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Genetic material of Lithuanian origin varieties, breeding lines and wild ecotypes representing P. pratense, P. bertolonii and P. phleoides species were studied for the most important agro-morphological and feeding value indicators as well as at the genetic level employing different biochemical–molecular markers. The water stress experiment clearly demonstrated the existence of different levels of water stress response in Phleum species, suggesting that P. phleoides might have evolved under conditions of limited water availability. “Blind” mapping by HRM was used successfully to map water stress response genes of timothy in the perennial ryegrass mapping population. In total, 12 putative water stress response genes were mapped in seven perennial ryegrass linkage groups.
Pasitelkus agromorfologinius, kokybės ir biocheminius – molekulinius metodus ištirtos lietuviškos kilmės pašarinių, žemaūgių bei stepinių motiejukų veislės, selekcinės linijos bei laukiniai ekotipai. Fiziologiniai sausros atsparumo tyrimų rezultatai įrodė, kad stepiniai motiejukai turi geriau išvystytą atsparumo sausrai mechanizmą. Pirmą kartą motiejukuose aptikti ekspresuojami atsparumo sausrai kandidatiniai genai HRM metodu sužymėti daugiametės svidrės genolapyje.

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Males, Jamie Oliver. "Structure-function relationships in the water-use strategies and ecological diversity of the Bromeliaceae". Thesis, University of Cambridge, 2017. https://www.repository.cam.ac.uk/handle/1810/267920.

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The Bromeliaceae is one of the largest and most ecologically diverse angiosperm families in the Neotropics. In recent years, this family has begun to emerge as a model system for the study of plant evolutionary ecology and physiology, and major advances have been made in understanding the factors involved in episodes of rapid diversification and adaptive radiation in specific bromeliad lineages. However, despite a long tradition of ecophysiological research on the Bromeliaceae, an integrative, evolutionarily-contextualised synthesis of the links between anatomical) physiological, and ecological aspects of bromeliad biology has hitherto been lacking. The overarching aim of this research project was therefore to use new quantitative data representing a wide range of bromeliad taxonomic and functional groups to elucidate how variation in leaf traits connected by structure-function relationships influences ecological differentiation among bromeliad taxa. Special emphasis was placed on hydraulic and water relations traits because of fast-paced contemporary developments in these fields. The methodologies employed included an assessment of the diversity of bromeliad hydrological habitat occupancy, quantification of key anatomical and physiological traits and their correlations, investigation of the links between vascular and extra-xylary anatomy and hydraulic efficiency and vulnerability, quantification of stomatal sensitivity to leaf-air vapour pressure deficit and stomatal kinetics, and a case study of trait-mediated niche segregation among congeneric epiphytic bromeliad species on the Caribbean island of Trinidad. The results highlight how divergences in a range of continuous and categorical anatomical traits underpin differences in physiological capacities and sensitivities, which in turn determine environmental relations and ecological distinctiveness. This research project therefore provides critical insights into the mechanistic basis of evolutionary diversification in a highly ecologically important family. It also represents the most comprehensive analysis of the significance of trait variation for ecological differentiation across any major radiation of herbaceous angiosperms.

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Ma'arup, Rohayu. "The use of genetic diversity from emmer wheat to improve bread wheat". Thesis, The University of Sydney, 2016. http://hdl.handle.net/2123/16634.

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Drought can be defined by Cambridge Dictionary as long period with little or no rain. Australia is the seventh largest wheat producer in the world, but it is the driest inhabited continent from the viewpoint of continental rainfall and streamflow. So, genetic improvement through crossing high-yielding cultivars of bread wheat with cultivated emmer wheats (had gone through early screening), subsequently backcrossing with bread wheat to increase bread wheat characteristics and producing doubled haploid (DH) from BC1F1 is one possible solution for increasing the yield stability of wheat in drought prone areas. The key point of this research study was to evaluate physiological and agronomic traits among the DH lines in optimum conditions for them to fully express their highest potential in 2013. Subsequently, selection was made among the DH lines for two years of trials under irrigated and rainfed conditions (to mimic drought) in 2014-2015 to evaluate genotypes that use water efficiently under drought stress. The relationship of physiology, phenology, and yield components in high water use efficiency genotypes revealed aspects of adaptation in northwestern NSW. The comparisons of bread wheat parents and their respective progenies (DH lines) were explored and diverse responses to soil water stress were observed. Biplot genotype main effect plus genotype by environment interaction (G+GE) of the multi-environment trials (METs) identified ideal genotypes that are stable cultivars across environment. These findings were also strengthened with GWAS analysis that revealed marker trait associations (MTAs) in water deficit conditions were not observed under the irrigated environments. Such lines would allow farmers to maintain income during drought years, as well as increase their income during wet years. The outcomes from this study should be worthwhile to the wheat industries in Australia and India, as some of domesticated bread wheat parents used were commercial cultivars in India.

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Boyd, Eric Stephen. "Biology of acid-sulfate-chloride springs in Yellowstone National Park, Wyoming, United States of America". Diss., Montana State University, 2007. http://etd.lib.montana.edu/etd/2007/boyd/BoydE0807.pdf.

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Barkaoui, Karim. "Structure fonctionnelle et écohydrologie de parcours méditerranéens établis le long d’un gradient de disponibilité en eau". Thesis, Montpellier, SupAgro, 2013. http://www.theses.fr/2013NSAM0030/document.

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Comprendre les relations entre écohydrologie et structure fonctionnelle des communautés végétales est une problématique croissante en écologie. Cette thèse a pour objectif d'analyser les effets d'un gradient de ressource édaphique sur la structure et le fonctionnement de parcours herbacés dans le sud de la France, en intégrant les niveaux de l'écosystème à la plante. Par modélisation du bilan hydrique, les différences d'utilisation de l'eau au niveau de l'écosystème ont été quantifiées pour cinq années contrastées révélatrices de la variabilité des propriétés des sols et du fonctionnement végétal. Utilisation de l'eau et productivité des plantes sont proportionnelles à la réserve utile des sols et à son taux de remplissage, suggérant un équilibre fonctionnel entre les communautés végétales et la disponibilité de l'eau locale. Par une approche ‘traits', nous avons ensuite montré que le ratio entre surface foliaire et surface racinaire totales de la communauté est le facteur déterminant une relation 'allométrique' entre évapotranspiration potentielle et capacité de prélèvements hydriques. La coordination entre les compartiments racinaire et aérien de la végétation dépend d'une suite d'adaptations architecturales et morphologiques. Des modifications d'abondances relatives spécifiques et le turn-over d'espèces génèrent une variabilité de morphologie et de fonctionnement des communautés permettant leur adaptation à des ressources limitées. Au niveau plante, une expérimentation de transplantation a permis de quantifier l'importance relative de la disponibilité hydrique et des interactions entre plantes sur la productivité individuelle de trois espèces-cibles. L'importance de la compétition s'est révélée plus élevée sous fort niveau de ressource et dépendait plus des relations hiérarchiques entre traits que de la biomasse. La compétition entre plantes affecte les axes de niche fonctionnelle des espèces de façon indépendante, avec une convergence de la ‘teneur en matière sèche des feuilles' pour des faibles valeurs mais une plus forte divergence fonctionnelle pour la ‘hauteur des plantes'. Cette approche fonctionnelle a permis d'éclairer le rôle de la diversité végétale dans la réponse des systèmes écologiques à des ressources hydriques variables. De plus, ces résultats sur les propriétés écohydrologiques des communautés naturelles peuvent contribuer à la conception d'agro-écosytèmes complexes mieux adaptés aux sécheresses intenses prévues dans le contexte actuel de changement climatique
Understanding the relationships between ecohydrology and functional structure of plant communities is a timely issue in plant ecology. From ecosystem to species levels, this works investigated the effects of a resource availability gradient on the structure and functioning of Mediterranean rangelands in Southern France. Using a water-balance modeling approach, differences in water-use at the ecosystem level were quantified across five contrasting years, accounting for the variability in both soil characteristics and vegetation functioning. Plant water-use and productivity scaled with soil water storage capacity and its filling rate, suggesting a functional equilibrium between plant communities and local water availability. Using a trait-based approach, we then showed that the ratio of total leaf area of the community on total root area determined an allometric relationship between potential evapotranspiration and water uptake capacity. The “coordination” between above- and belowground compartment of the vegetation was achieved by a suite of architectural and morphological adaptations. Modifications of species relative abundances and species turn-over explained morphological and functioning adaptations to cope with limiting resources. Finally at species level, a removal experiment allowed to quantify the relative importance of water limitations and effects of plant-plant interaction on individual plant productivity of three target species of graminoïds. The importance of competition increased with soil resource availability and depended more on trait-trait hierarchical distances among species than standing biomass. Competition among plants affects the axes of the functional niche of species independently, leading to the convergence of leaf dry matter content towards low values but to greater functional divergence for plant height. Overall, this functional approach provided an integrative understanding of the role of plant diversity in the response of ecological systems to changes in water availability. Furthermore, these results on ecohydrological properties of natural communities can contribute to the design of complex agro-ecosystem better adapted to intense droughts predicted under climate change

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King, Andrew Giuseppe. "Interactions between riverbed morphology, water chemistry and microbial diversity, and its impact on pollutant biodegradation". Thesis, University of Warwick, 2014. http://wrap.warwick.ac.uk/71000/.

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Riverine environments are stressed and damaged by anthropogenic actions, with chemical contamination a key factor, identified as potentially adversely impacting the aquatic network. Standardised Organisation for Economic Co-Operation and Development (OECD) tests are used to establish biodegradation rates of chemicals in the environment, however these tests are conducted in unrealistic conditions deficient of environmental realism. Increasing the environmental realism of OECD tests has the capacity improve prediction of chemical persistence and identify potential for damage to the environment. Moreover, the interactions between bedform, microbial biofilm communities and chemical biodegradation at the sediment-water interface are not considered in OECD tests. The current project explored the effects of bed-form characteristics on biofilm development and the consequences of sediment on biodegradation at the sediment-water interface. Novel flume systems were designed, constructed and used to develop methodologies to investigate the impact of bed form on hyporheic exchange. River water and sediment were sampled from a stretch of the River Dene (Wellesbourne, UK) and used as microbial inocula in chemical biodegradation studies using a series of specially designed re-circulating flume systems and ex-situ bottle experiments. Flume experimentation quantified the rate of microbial community development, topographical location and effective depth penetration on sediment beds within artificial watercourses, whilst simultaneously identifying the impact that this biofilm development possessed on hyporheic exchange. The effects of light and inoculum source on para-nitrophenol (PNP) biodegradation were also determined following OECD regulatory test protocols in an attempt to evaluate the realism of chemical biodegradation tests. Experimental data showed that microbial development varied on different sediment bed profiles, and that biofilms significantly reduced the rate of hyporheic exchange on small (0.5 mm), but not large (2.0 mm) sediment particle size bed materials. Additionally, this study found that light inhibited PNP degradation in all tests and that sediment sieving utilised in OECD tests decreased rates of biodegradation of PNP. This project revealed the importance of microbial biofilms in determining hyporheic exchange. However, further experimental work is recommended to investigate hyporheic exchange in heterogeneous sediments, whilst developing more inclusive approaches for chemical risk management by Regulatory bodies.

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Fawcett, James. "Muddy Waters: A Molecular Approach to Clarifying Freshwater Mussel Diversity in Australia". Thesis, Griffith University, 2009. http://hdl.handle.net/10072/367764.

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Historically, when the terms “conservation, threatened, endangered or extinct” were used, it was in reference to vertebrate animal species. Funding for conservation and policy implementation for protection of invertebrates has historically been difficult, even though 95% of all animal species are invertebrates and are an important component of many ecosystems. Human impact on the earth has influenced the natural population structure of many organisms, through habitat destruction, fragmentation and degradation. Issues that affect population structure and dispersal are heightened when that species is confined to a specific range or habitat. This is especially paramount for aquatic organisms with the slightest change in weather pattern, damage to riparian zones or the stream environment, or alteration to stream engineering and water flow resulting in significant impacts to the stream biota. Freshwater mussels are organisms that have been found to be seriously affected by changes to stream conditions. Because mussels filter the water column, they are generally the first group of animals to react if contaminants enter a system and as a result freshwater mussels are considered by many scientific and government agencies worldwide as key indicator species for stream health assessments. Freshwater mussel conservation is a relatively unexplored field within Australia and little is known about mussel recruitment and patterns of population connectivity. Mussel taxonomy in Australia is based entirely on shell morphology, although local environmental conditions have been shown to have significant effects on shell morphology. Therefore, basing taxonomy purely on shell morphological characteristics may not to be systematically meaningful. Before effective conservation measures can be implemented within Australia, clarification of contemporary mussel diversity is required.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Environment
Science, Environment, Engineering and Technology
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Peter, Hannes. "Diversity and Ecosystem Functioning : Redundancy and Resilience in Freshwater Bacterial Communities". Doctoral thesis, Uppsala universitet, Limnologi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-160780.

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Bacteria are immensely diverse and hold key-positions in essentially all biogeochemical cycles. In freshwater ecosystems, bacteria degrade and mineralize organic compounds, linking the pool of dissolved organic matter to higher trophic levels. Aware of the global biodiversity loss, ecologists have started identifying the relationship of diversity and ecosystem functioning. Central to this is the question if species can functionally replace other species, hence being functionally redundant. Functional redundancy might allow communities to maintain functioning when diversity is lost. Due to their large numbers and great diversity, bacterial communities have been suspected to harbor large amounts of redundancy. The central aim of this thesis is to investigate the coupling of diversity and ecosystem functioning of bacterial communities and to understand how environmental perturbation affects this relationship. I manipulated the diversity of complex communities by a dilution technique, and measured the performance of bacterioplankton and biofilm-forming communities at different diversities. Reduction of bacterial diversity differently affected different functions, and that the presence or absence of certain species might be causing this pattern. However, for ecosystems to function, the interplay of multiple functions, i.e. multifunctionality, has to be sustained over long periods of time. In bacterial biofilm communities reduced diversity affected multifunctionality, as reflected by extracellular enzyme activities. A continuous cultivation system was used to address the importance of diversity for resistance and resilience upon environmental perturbation. The analysis of co-occurrence of bacterial taxa showed that the communities form a dense network before the perturbation and that these patterns are disturbed by the environmental perturbation. The final chapter of the thesis presents experimental evidence for the positive effects of temporal and spatial refuges for bacterial communities and the functions they provide. Overall, I found several indications for a lower amount of functional redundancy as previously assumed and it becomes apparent from this thesis that a multifunctional perspective and the consideration of environmental heterogeneity is pivotal.

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Alves, Cristina Consolado Santos. "Métodos e medições de caudais. Análise e comparação de diversos métodos hidrométricos". Master's thesis, ISA/UTL, 2011. http://hdl.handle.net/10400.5/3945.

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Mestrado em Engenharia do Ambiente - Instituto Superior de Agronomia
In Portugal there are numerous water resources, water potential distributed mainly in small and medium rivers. There is urgent need of quantifying and managing these resources. The Division of Water Resources INAG, is responsible for managing the hydrometric network in the country, for decades the work of hydrometry is developed, naturally over time the technological evolution of tools and techniques for measuring the quantities involved the hydraulic phenomena. For decades the technologies for measuring water velocity and calculation methods have been refurbished. Nowadays there is a wide variety of equipment with different features and functionalities, for the method of measurement and calculation of flow. For a proper quantification management of water resources is essential, flow measurements in various streams, with the knowledge of these values and their evolution over time, it is possible to determine a flow curve, which is representative of the flow at a given period of time. This work has as objective an analysis to historical data relating to joint measurements of water depth and corresponding flow, the traditional method, which was used by INAG in order to get their flow curves. Also covered are the different flows measuring devices and comparison between the latest electromagnetic and Stream Pro.

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Stamp, Michelle. "Oomycota in Scottish water catchments : diversity and relationships between species, riparian land use and ecosystem function". Thesis, University of Aberdeen, 2015. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=230062.

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Oomycetes are eukaryotic fungus-like microorganisms that are known to be pathogenic to plants and animals, causing both ecological and economic damage. Animal pathogenic oomycetes, such as Saprolegnia species are destructive pathogens to many aquatic organisms and are found in most parts of the world. Phytophthora species cause a number of plant diseases. Pythium are less understood as many of these species are saprotrophs which are not thought to be pathogenic. Oomycete research has focussed mainly towards the characterisation and control of pathogenic species with very little information on the ecology of Oomycetes. In this thesis, oomycete species were isolated from water samples collected from rivers in Scotland and Northern England. Baiting and water filtration were used to compare the reliability of both methods, and nested PCR was used to compare the number and types of species obtained in comparison to conventional culturing methodologies. The results suggest that water filtration provided a fast, reliable method for isolating abundant, hardier species such as Pythium undulatum, Saprolegnia diclina, Saprolegnia delica, and Saprolegnia ferax. Water chemistry, surrounding land use, seasonality and land elevation were found to be important factors in Oomycete diversity. Nested PCR of oomycetes directly from filters to obtain target DNA from organisms which are more difficult to culture or less numerous proved to be useful for some species, but will need more refinement of primer and methodologies to obtain species of interest. Sampling of the rivers resulted in the isolation of three new Pythium spp. isolated from the Rivers Spey and Dochart in Scotland. Phylogenetic analysis, infection studies, growth rates and microscopy were used to characterise these three species.

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Vega-Rodriguez, María. "Influence of Water Quality on Stony Coral Diversity and Net Community Productivity in the Florida Keys". Scholar Commons, 2016. http://scholarcommons.usf.edu/etd/6598.

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Worldwide, coral cover has declined at rates that have often exceeded 5% per year since the 1980’s. Populations of scleractinians (stony corals) in the Florida Keys reef tract have declined as well, with some communities declining at rates > 3% per year. Decreased water quality (e.g., steady increases in the ocean water temperatures and increased pollution, nutrients, or water turbidity due to coastal runoff) are commonly attributed to this decline. But actual linkages between variability and trends in these environmental parameters, and in stony coral diversity and ecosystem functions such as net community production, have not yet been well characterized. With this research, I examined the influence of water quality (water temperature, nutrients and turbidity) on stony coral diversity and net community productivity in shallow-water reef ecosystems of the Florida Keys between 1996 and 2010. Differences in stony coral diversity in Florida Keys patch reefs with respect to sea surface temperature (SST) variability are evaluated in Chapter Two. Habitat-specific differences in stony coral diversity with respect to changes in a suite of environmental parameters (water turbidity, nutrients, water temperature and depth) are addressed in Chapter Three. Differences in daytime net community production and light-adapted stony coral photosynthetic efficiencies among three reef sites with different turbidity levels and seasons (May and October) are presented in Chapter Four. Environmental parameters examined to characterize the differences in stony coral diversity across the Florida Reef Tract included satellite-derived sea surface temperature [SST] and Degree Heating Weeks [DHWs], field observations of bio-optical properties of the water, and nutrient concentrations. These parameters were compared with live coral cover and species richness, net community production, and coral photo-physiological observations. In Chapter Two, I found that stony coral cover and diversity was higher in patch reefs of the Florida Keys relative to offshore and deeper reefs. Generally, patch reefs were characterized by intermediate to high SST variability (≥7.0°C2). Intermediate SST variance (7.0–10.9°C2) was correlated with higher diversity indices for patch reefs of the Upper (Shannon Diversity: 1.2–1.5) and Middle Keys (Species Richness: 13–19), suggesting that stony coral species in these habitats are either adapted to intermediate temperature ranges or thermal acclimation has taken place for individual colonies. Additionally, I found that found that years for which cold and warm-water extremes coincided (i.e., highest SST variance), such as 1997-98 and 2009-2010, led to significant reductions in both H’ and SR. Coral bleaching and mortality were associated with exposure to cold- and warm-water temperature extremes and the combination of both extremes were associated with reductions in stony coral diversity. The highest species richness and abundance were found in patch reefs of the Middle Keys, despite exposure to the warmest water-temperature anomaly events (as indicated by DHWs exceeding the coral bleaching threshold of 4) observed during the summers of 1998 and 2010. In Chapter Three, I found that the environmental parameters that best explained the differences in stony coral diversity (species composition and abundance) on patch reefs of the Florida Keys were water turbidity, nutrients, surface water temperature, % surface oxygen saturation and chlorophyll a concentrations averaged over a period of 24 months, along with depth (F = 4.4, R2 = 0.66, R2adj. = 0.40, p < 0.05). Surface water turbidity and depth were the most relevant environmental parameters driving the differences in stony coral diversity (R2 = 0.17, p < 0.05, R2 = 0.10, p < 0.05, respectively). The influence of these environmental parameters decreased towards offshore shallow and deep reefs. In the Florida Keys, stony coral diversity was the highest at patch reefs of the Middle and Lower Keys where exposed to higher water turbidity and nutrients than those in the Upper Keys located in clearer waters. This suggests that, at long-term scales, corals in patch reef environments exposed to higher water turbidity and water temperature variabilities (as reported in Chapter Two) might be better able to withstand thermal and light-induced stress. Moreover, a short-term study (described in Chapter Four) indicated that the net community production (NEP) was similar among sites with different water turbidity levels (i.e., Cheeca Rocks and Crocker Reef; Upper Keys and Sugarloaf Key; Lower Keys) and seasons (May or October). However, the light-adapted photosynthetic efficiencies (F/Fm’) varied spatiotemporally. The highest F/Fm’ values (0.57–0.69) were found at the nearshore patch reef of Sugarloaf Key, Lower Keys, in October 2012. At this patch reef, high light attenuation (Kd (488) = 0.12 m-1) was associated with absorption by colored dissolved organic matter and exacerbated by particulates following thunderstorms. The lowest F/Fm’ values ( This study represents a baseline against which future observations on coral reef biodiversity and net community production in the Florida Keys reef tract may be evaluated.

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Ramoejane, Mpho. "Genetic diversity, evolutionary relationships and conservation of southern African Labeo fishes in relation to water management". Thesis, Rhodes University, 2017. http://hdl.handle.net/10962/5209.

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Labeo spp. are large, herbivorous fishes that are important components of aquatic ecosystems and are a high conservation priority in South Africa. This thesis contributes to determination of conservation priorities for Labeo umbratus (Smith 1841) by resolving the taxonomic status of this species in the evolutionary context of southern African Labeo spp., assessing the presence of unique lineages in historically isolated river basins, and assessing the threat of intra- and interspecific hybridisation associated with introductions. Phylogenetic analyses of five DNA sequence data sets (cytochrome c oxidase subunit I gene [COI], cytochrome b gene [Cyt b], Recombination activating gene 1 [Rag1], COI+Rag1 and COI+Cyt b+Rag1) showed that the Labeo umbratus group (sensu Reid, 1985), which comprises the species Labeo umbratus, Labeo capensis (Smith 1841), Labeo seeberi Gilchrist and Thompson 1911 and Labeo rubromaculatus Gilchrist and Thompson 1913, is monophyletic, morphologically distinct and geographically disjunct from other African Labeo spp. groups except in the Tugela River system were L. rubromaculatus co-occurs with Labeo molybdinus Du Plessis 1963. Phylogeographic analysis of mitochondrial DNA (Cyt b) sequence data demonstrated that the populations of the L. umbratus from the Orange and the southward-flowing river systems are reciprocally monophyletic and were identified as evolutionary significant units. The populations in the southward-flowing river systems were further divided into southwestern (Gourits and Gamtoos) and southeastern (Sundays, Bushmans, Great Fish, Keiskamma, Buffalo and Nahoon) polyp hyletic sublineages. Four management units (Gourits Basin; Gamtoos Basin; Sundays+Bushmans+Great Fish River Basins; and Keiskamma+Buffalo+Nahoon River Basin) were not reciprocally monophyletic but were proposed on the basis of containing unique haplotype frequencies for conservation purposes. To evaluate the threat of hybridisation to the genetic integrity of L. umbratus, the occurrence of Labeo umbratus x L. capensis hybrids was investigated using mtDNA Cyt b and nDNA S7 intron sequence data and morphological data. Genetic evidence for interspecific hybridisation was detected for populations in two impoundments, Hardap Dam (Orange River Basin) and Darlington Dam (Sundays River Basin, Eastern Cape, South Africa). Some putative hybrids were identifiable morphologically on account of intermediacy between the parental species in meristic and morphometric characters. Translocation via direct stocking (Hardap Dam) or via an inter-basin water transfer scheme (Darlington Dam) was identified as a driver for hybridisation. Introductions associated with an inter-basin water transfer scheme has resulted in introgression between the previously isolated Orange River and southern lineages of L. umbratus. Further translocation of fish from these affected areas to non-contaminated river systems and impoundments such as Kat River (Great Fish River) and Slagboom (Sundays River) should be avoided.

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