Dissertations / Theses: 'Rivers- Rivers basin and systems'

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Banerjee, Malini De. "High-Frequency Nitrate Monitoring in Dynamic River Systems: the Case of Three Iowa Rivers in the Mississippi Basin." Diss., University of Iowa, 2013. https://ir.uiowa.edu/etd/4818.

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High frequency water quality monitoring presents unique and unlimited opportunities of exploring spatio-temporal variation in water quality. Knowledge gained from analyzing high frequency water quality data can provide more clarity regarding transportation and processing of water constituents over time and space and scale. This study analyzes high frequency discharge, nitrate load and concentration data for three watersheds of different sizes - Cedar River Watershed, North Raccoon and Middle Raccoon. Each of these sites were monitored for 2-3 calendar years. Sudden spikes in discharge, nitrate concentration and load data, also defined as "events" were analyzed in great detail to understand the patterns in event occurrence and event intensity. Smaller watersheds seemed to have sharper and "flashier" events compared to bigger watersheds. Nitrate concentration events were flatter in shape compared to discharge and nitrogen load events. The relationship between nitrogen concentration and discharge was found to be varying over time, unlike the relationship between nitrate load and discharge, which were almost perfectly correlated for most site-year combinations. Based on more than 40,000 simulations, it was determined that high frequency water quality sampling is not only efficient in capturing minute spatio-temporal variations but can also capture nitrate exceedances to a greater degree. High frequency sampling was also associated with higher yield ratio in nitrate load estimates, not only during high flow periods, but also during the non-high-flow period.

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Ramos, Eunice Pereira. "Energy systems analysis of transboundary river basins in a nexus approach: the Sava river basin study case." Master's thesis, Universidade de Aveiro, 2015. http://hdl.handle.net/10773/15833.

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Mestrado em Sistemas Energéticos Sustentáveis
Resource management policies are frequently designed and planned to target specific needs of particular sectors, without taking into account the interests of other sectors who share the same resources. In a climate of resource depletion, population growth, increase in energy demand and climate change awareness, it is of great importance to promote the assessment of intersectoral linkages and, by doing so, understand their effects and implications. This need is further augmented when common use of resources might not be solely relevant at national level, but also when the distribution of resources ranges over different nations. This dissertation focuses on the study of the energy systems of five south eastern European countries, which share the Sava River Basin, using a water-food(agriculture)-energy nexus approach. In the case of the electricity generation sector, the use of water is essential for the integrity of the energy systems, as the electricity production in the riparian countries relies on two major technologies dependent on water resources: hydro and thermal power plants. For example, in 2012, an average of 37% of the electricity production in the SRB countries was generated by hydropower and 61% in thermal power plants. Focusing on the SRB, in terms of existing installed capacities, the basin accommodates close to a tenth of all hydropower capacity while providing water for cooling to 42% of the net capacity of thermal power currently in operation in the basin. This energy-oriented nexus study explores the dependency on the basin’s water resources of the energy systems in the region for the period between 2015 and 2030. To do so, a multi-country electricity model was developed to provide a quantification ground to the analysis, using the open-source software modelling tool OSeMOSYS. Three main areas are subject to analysis: first, the impact of energy efficiency and renewable energy strategies in the electricity generation mix; secondly, the potential impacts of climate change under a moderate climate change projection scenario; and finally, deriving from the latter point, the cumulative impact of an increase in water demand in the agriculture sector, for irrigation. Additionally, electricity trade dynamics are compared across the different scenarios under scrutiny, as an effort to investigate the implications of the aforementioned factors in the electricity markets in the region.
As políticas de gestão de recursos são, frequentemente, desenvolvidas e planeadas para fazer face às necessidades específicas de determinados sectores, sem terem em conta os interesses de outros sectores que também utilizam os mesmos recursos. Num cenário de esgotamento de recursos, crescimento populacional, aumento da procura de energia e sensibilização para as mudanças climáticas, é de grande importância promover a avaliação de ligações intersectoriais e, ao fazê-lo, perceber as suas implicações e efeitos. Esta necessidade é ainda maior quando o uso comum de recursos não é relevante apenas a nível nacional mas também quando a distribuição de recursos se alarga a outras nações diferentes. A presente dissertação centra-se no estudo dos sistemas energéticos de cinco países da região sudeste da Europa que partilham a bacia do rio Sava (BRS), recorrendo a uma abordagem da relação água-alimentação(agricultura)-energia. No caso do sector de produção de eletricidade a utilização da água é essencial para a integridade dos sistemas energéticos, pois a produção de energia nos países da BRS provém de duas tecnologias principais que dependem da água: centrais hídricas e térmicas. A título de exemplo, em 2012, da produção de eletricidade dos países da BRS, 37% foi gerada a partir de energia hídrica e 61% produzida por centrais térmoelétricas. Olhando para a BRS, em termos da potência instalada existente, a bacia acomoda cerca de um décimo de toda a potência hidroelétrica instalada e, ao mesmo tempo, contribui com água para os sistemas de arrefecimento de 42% da potência total instalada das centrais térmicas em funcionamento na região. Este estudo integrado do nexus para a energia explora a dependência entre os sistemas energéticos da região com os recursos hídricos da bacia, entre os anos 2015 e 2030. Para tal, foi desenvolvido um modelo do sistema elétrico transnacional para fornecer uma base quantificavel à análise, usando o software de código aberto OSeMOSYS. A análise é feita a três áreas principais: a primeira corresponde ao impacto das estratégias de eficiência energética e energias renováveis no mix energético de produção de eletricidade; a segunda relaciona-se com os potenciais impactos das alterações climáticas, atendendo a previsões de um cenário moderado de mudanças climáticas e, por último, decorrente do ponto anterior, o impacto cumulativo do aumento da procura de água para irrigação no sector agrícola. Este estudo inclui ainda uma comparação da dinâmica da exportação/importação de eletricidade nos diferentes cenários, com o objetivo de investigar as implicações que os fatores mencionados anteriormente poderão ter nos mercados da eletricidade dos países desta região.

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Zhao, Bo. "Occurrence and fate of N-nitrosamines and their formation potential in wastewater system and receiving rivers." Kyoto University, 2019. http://hdl.handle.net/2433/244538.

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Yitbarek, Baye Andarge. "Hydrogeological and hydrochemical framework of complex volcanic system in the Upper Awash River basin, Central Ethiopia : with special emphasis on inter-basins groundwater transfer between Blue Nile and Awash rivers." Poitiers, 2009. http://theses.edel.univ-poitiers.fr/theses/2009/Yitbarek-Baye-Andarge/2009-Yitbarek-Baye-Andarge-These.pdf.

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Une approche utilisant plusieurs méthodes convergentes a été mise en oeuvre pour étudier le cadre hydrogéologique du système aquifère volcanique fracturé et complexe du bassin supérieur du fleuve Awash situé sur le bord du Rift éthiopien. L'écoulement des eaux souterraines et les mécanismes de recharge des différents aquifères ont été étudiés à l'aide de méthodes conventionnelles de terrain, de l'hydrochimie, de l'hydrologie isotopique et de la modélisation numérique des flux souterrains. Des relations lithohydrostratigraphiques ont été établies à partir des logs lithologiques de forages exploratoires profonds. Les résultats montrent un modèle d'écoulement et des caractéristiques hydrauliques des différents aquifères volcaniques très complexes. La corrélation litho-hydrostratigraphique indique que l'aquifère basaltique inférieur, constitué de scories poreuses et perméables, est continu tout le long depuis le Nil Bleu jusqu'à la zone étudiée. L'analyse de la variation temporelle et spatiale des échantillons d’eau provenant d'endroits différents a révélé des interactions nettes entre l'eau souterraine et l'eau superficielle. De nouvelles évidences des transferts d'eau inter-bassins sont apparues. Deux aquifères basaltiques régionaux (l'aquifère supérieur et l'aquifère inférieur) ont été identifiés, montrant des signatures hydrochimiques et isotopiques bien distinctes. Dans la partie sud de la zone étudiée, l'aquifère supérieur et l'aquifère inférieur forment un système aquifère régional non confiné. Dans les parties nord et centrale du bassin au contraire, il apparaît que les deux systèmes sont séparés par un aquiclude régional, donnant lieu par endroits à des puits artésiens. Les eaux souterrainex provenant des puits d'exploration profonds (plus de 250 m) pénétrant l'aquifère basaltique inférieur et des puits situés au sud se sont révélées modérément mineralisées (TDS 400-650 mg/l), avec une composition isotopique stable, relativement moins enrichie et avec presque pas de tritium. Par contre, l'aquifère supérieur superficiel a une concentration ionique moins importante, davantage enrichie isotopiquement. Les résultats des différentes méthodes montrent clairement qu'il existe un transfert d'eau souterraine du nord du bassin adjacent du Nil Bleu vers le bassin supérieur du fleuve Awash. Les résultats convergent également pour attester de l'origine commune de la recharge et de la continuité hydraulique de l'aquifère basaltique inférieur exploité par des forages. Ceci peut avoir des implications pratiques capitales car l'existence d'importantes ressources d'eau souterraine en profondeur peut résoudre les problèmes d'approvisionnement de nombreuses villes, y compris la capitale, Addis Ababa. Ces résultats pourront aussi contribuer à mettre à jour d'autres aquifères régionaux le long des limites du rift dans des zones ayant une structure hydrogéologique similaire à celle du bassin supérieur du fleuve Awash
Integrated approach has been used to investigate the hydrogeological framework of a complex fractured volcanic aquifer system in the Upper Awash river basin located at the western shoulder of the Ethiopian rift. The groundwater flow system and mechanism of recharge of different aquifers have been studied using conventional hydrogeological field investigations, hydrochemistry, isotope hydrology and numerical groundwater flow modeling techniques. Litho-hydrostratigraphic relationships were constructed from lithologic logs obtained from exploratory drilling of deep boreholes. The result indicates quite complex flow pattern and hydraulic characteristics of the different volcanic aquifers. The litho-hydrostratigraphic correlation indicates that the permeable and porous scoraceous lower basaltic aquifer is extended laterally all the way from the Blue Nile Plateau to the study area. . The analysis of the temporal and spatial variation of water samples from different places revealed clear undwater-surface water interactions. New evidences have also emerged on the inter-basin groundwater transfer. Two distinct regional basaltic aquifers (Upper and lower) are identified showing distinct hydrochemical and isotopic signatures. In the southern part of the study area the upper and lower aquifers form one unconfined regional aquifer system. In the northern and central part of the basin, it appears that the two systems are separated by regional aquiclude forming confined aquifers, in places with artesian wells. The groundwater from the deep exploratory wells (>250m) tapping the lower basaltic aquifer and wells located in the south were found to be moderately mineralized (TDS: 400-600 mg/l), with relatively depleted stable isotope composition and with almost zero tritium. In contrast, the upper shallow aquifer has lesser ionic concentration, more isotopically enriched. Evidences from the different methods clearly indicate inter-basin groundwater transfer from the Blue Nile basin to the Upper Awash basin. The evidences also converge to testify common origin of recharge, presence of hydraulic connectivity for systems tapping the lower basaltic aquifer. This has enormous practical implication in finding large groundwater reserve at a greater depth that can solve the current water supply problems of the community including the capital Addis Ababa. It will also have important role in finding more regional aquifers along the plateau-rift margins in many areas having similar hydrogeological setup as the study area

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Lorenzoni, Laura. "Sediment transport and distribution over continental shelves: a glimpse at two different river-influenced systems, the Cariaco Basin and the Amazon Shelf." Scholar Commons, 2012. http://scholarcommons.usf.edu/etd/4132.

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The aim of this dissertation was to understand lithogenic suspended sediment transport mechanisms and distribution in two river-influenced margins: The Cariaco Basin, Venezuela, and the Amazon Shelf, Brazil. Lithogenic sediment input in the Cariaco Basin is controlled by small mountainous rivers (SMR), while in the Amazon Shelf it is dominated by the Amazon River, the largest river in the world in terms of freshwater discharge (~20% of global riverine discharge). Optical transmissometer measurements were coupled with particulate organic matter (POM) observations to understand changes in the geochemical composition of suspended sediment and spatial/temporal distributions over the two regions of interest. In the Cariaco Basin sampling was conducted during the rainy seasons of September 2003, 2006 and 2008, and during the upwelling period (dry season) of 2009. Our results suggest that bottom nepheloid layers (BNL) originating at the mouth of the SMR discharging into the Cariaco Basin are a major delivery mechanism of terrigenous sediments to the basin's interior year-round. Intermediate nepheloid layers (INL) were also observed near the shelf break (~100m) and appear to effectively carry terrigenous material laterally from the shelf to deep waters, thereby providing a plausible supply mechanism of the terrestrial material observed in sediment traps, deployed >70 km offshore as part of the CARIACO Ocean Time-Series. These findings highlight the importance of small, local rivers in the Cariaco Basin as sources of terrestrial material. Indeed, the low isotopic composition of particulate organic carbon (δ13Corg, ~-30 - -24 ‰) carried by the BNL suggests that this material was continentally derived. BNL δ13Corg also changed with season, indicating that the geochemical composition of BNL reflects particle source. These nepheloid layers contained relatively low POM concentrations (average of 10%), agreeing well with published data, yet the fine sediment of the BNL may serve as mineral ballast, enhancing the sinking velocities of POC and thus increasing the efficiency of the biological pump in Cariaco. We suggest that during the transition between the upwelling and rainy season BNL deliver sediment to the deep Cariaco Basin in pulses. During upwelling, BNL are retained on the inner shelf by onshore Ekman transport associated with upwelling. The nepheloid layers are later released as the upwelling subsides; this, coupled with high river discharge rates, may explain the seasonal pulse of sediment observed at the end of the upwelling period (May) in the sediment trap array. The SMR in Cariaco also have the capacity to deliver large amounts of sediment to the Cariaco Basin during episodic events, such as earthquakes and floods. During September 2008 a sediment density flow was observed in the eastern Cariaco Basin, likely triggered by a magnitude 5.2 earthquake that occurred on August 11, 2008 off the city of Cumaná. Elevated suspended sediments near the bottom were observed at the mouth of the Manzanares Canyon (> 90 g m-2, over a depth of 165 m) and decreased to ~11 g m-2 (over a depth of 40 m) 42 Km away from the canyon's mouth at the CARIACO Ocean Time-Series site (10.5° N, 64.67° W). The sediment flux associated with this single event was ~ 10% of the total annual sediment flux that typically reaches the Cariaco Basin deep seafloor. Average carbon to nitrogen atomic ratios (C/N) as well as C and N isotopic composition confirm that most of the organic matter transferred by the sediment flow was of continental origin (C/N ratios of ~19.3, δ13C of -27.04 ‰, and δ15N of 6.83 ‰). The Manzanares River mouth is located at the head of the canyon, and likely supplies most of the fine grained sediments and fresh organic carbon that accumulate in the upper part of the canyon. This suggests that the canyon is an active depositional center, and its proximity to the Manzanares River and Cariaco Basin is critical for sediment supply offshore, which in turn can have a significant impact on the long-term sequestration of carbon into the deep basin. The nutrient and sediment biogeochemistry of the outer Amazon Shelf was studied in February-March 2010 to replicate observations made by the AmasSeds study in 1989-1991. These transects roughly corresponded to the AmasSeds Open Shelf (OS) and River Mouth (RM) transects. Onshore winds (~6 m s-1) contained the Amazon plume within ~120 Km of the coast; the plume was visible only in the mid-shelf stations located closest to the coast in the OS transect. Within the river plume, surface dissolved inorganic nutrient concentrations were near zero, except for silicates (4-6 μM). Coupled with oxygen supersaturation (AOU < 1), this suggested complete biological uptake of the major dissolved inorganic nutrients (N, P). Dissolved organic carbon (DOC) was also highest within the plume (average of 116 μM), decreasing to ~73 μM in oceanic waters. Total suspended solids (TSS) in surface waters within the plume were ~1-1.5 mg l-1, decreasing to ~0.2-0.3 mg l-1 in all other sampled stations both over the shelf and in deeper waters. TSS were highest within BNL (22-33 mg l-1) observed over the inner shelf; BNL were not observed outside the area of the Amazon plume. Suspended particulate organic carbon (POCsusp) showed a depleted δ13C isotopic signal (~-25 ‰ to -28 ‰) in surface and bottom waters, suggesting terrestrial provenance. Within the BNL, %POC was low (0.6-0.9%, as compared to 7-18% in surface waters), showing extensive and rapid decomposition of organic matter over the shelf. Atomic C/N ratios in particulate organic matter both in surface waters and within BNL were relatively close to Redfield's (8-14) and relatively stable over the area sampled. Particulate atomic organic carbon vs. particulate organic phosphorous (POC/POP) ratios were also low within the BNL (~110) and increased offshore (>500), suggesting a direct input of particulate P from the Amazon River or from reworked surface sediments. The fraction of POC in surface sediments was also low (0.73 ±; 0.56%; N = 5) and relatively uniform across the region sampled. We estimated instantaneous fluxes of 38.7 metric tons TSS s-1, 0.24 metric tons POC s-1 and 6.42 x 10-3 metric tons POP s-1 northwestward over an area extending between ~50 Km and 120 Km offshore. Our TSS estimates are 30% lower than those calculated by Nittrouer et al. (1986) during peak discharge of the Amazon. We also calculated that some 1.50 Tg yr-1 of DOC were being flushed northwestward along the outer shelf annually, which represent ~6% of the total DOC transported by the Amazon. By analyzing these two geographical settings it was possible to compare and contrast transport mechanisms of continentally-derived material and establish the relative importance of each mechanism in their different environment. There is still much to be understood regarding BNL in the Cariaco Basin, such as their role within the Manzanares Submarine Canyon with regards to sediment contribution and deposition. Additionally, during the last 30 years, anthropogenic influences on the small rivers around the Basin have significantly altered the drainage and sediment loads, yet reliable data to quantify the level of influence and change over time are not available. We need a better understanding of the natural variability of these small, tropical fluvial systems, trends and impact of episodic events, to better interpret the climate record stored at the bottom of the basin and predict future ecosystem changes in the region. In the Amazon Shelf, more accurate estimates of DOC, POC and POP fluxes northwestward are warranted. The magnitude of the Amazon River discharge dampens changes that have occurred in the last 20 years within the Amazon Basin, suggesting that historic Amazon Shelf sediment and carbon estimates are still valid. The data presented here adds to the growing body of literature that highlights the significance of river-influenced continental margins as sites of organic carbon deposition, remineralization export and sequestration.

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Latrubesse, Edgardo M., Eugenio Y. Arima, Thomas Dunne, Edward Park, Victor R. Baker, Fernando M. d’Horta, Charles Wight, et al. "Damming the rivers of the Amazon basin." NATURE PUBLISHING GROUP, 2017. http://hdl.handle.net/10150/625952.

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More than a hundred hydropower dams have already been built in the Amazon basin and numerous proposals for further dam constructions are under consideration. The accumulated negative environmental effects of existing dams and proposed dams, if constructed, will trigger massive hydrophysical and biotic disturbances that will affect the Amazon basin's floodplains, estuary and sediment plume. We introduce a Dam Environmental Vulnerability Index to quantify the current and potential impacts of dams in the basin. The scale of foreseeable environmental degradation indicates the need for collective action among nations and states to avoid cumulative, far-reaching impacts. We suggest institutional innovations to assess and avoid the likely impoverishment of Amazon rivers.

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Wong, Wing-sze. "Water chemistry in the Kam Tin basin, natural and authropogenic influences." Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/hkuto/record/B38605843.

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Fung, Lai-kuen. "An Investigation of the stream water chemistry in a small drainage basin in Shek Kong, Hong Kong." Hong Kong : University of Hong Kong, 2000. http://sunzi.lib.hku.hk/hkuto/record.jsp?B22288077.

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Maddy, Darrel. "The Middle Pleistocene development of the rivers Severn and Avon." Thesis, Royal Holloway, University of London, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.311980.

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Lorenzoni, Laura. "The influence of local rivers on the eastern cariaco basin, Venezuela." [Tampa, Fla.] : University of South Florida, 2005. http://purl.fcla.edu/fcla/etd/SFE0001152.

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Fung, Lai-kuen, and 馮麗娟. "An Investigation of the stream water chemistry in a small drainage basin in Shek Kong, Hong Kong." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B22288077.

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Jenkins, William Owen. "Decision support systems in river basin management." Thesis, Imperial College London, 1988. http://hdl.handle.net/10044/1/47123.

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Yilmaz, Deniz. "Estimation Of Specific Flow Duration Curves Using Basin Characteristics Of Rivers In Eastern Blacksea Basin." Master's thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613279/index.pdf.

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New and renewable energy resources are important in view of reduction of greenhouse gasses causing climate change and in eliminating of dependence on foreign sources in energy respects. Within this context, hydraulic energy is evaluated as one of the prior energy resources that should be utilized. Turkey has 26 basins and Eastern Black Sea Basin is one of the most feasible basins with a lot of small hydroelectric power plants. In the other hand, there is not enough number of discharge gauging stations in the basin. For that reason, up to now generally area ratio method has been used to estimate the project discharges of small hydroelectric power plants. Objective of this study is to estimate &ldquo
the project discharge&rdquo
which is corresponding to 5 flow percentiles (5%, 10%, 15%, 20%, 25%) depending on topographical, meteorological, hydrologic and soil-land cover parameters through developing a multilinear statistical model for Iyidere Basin as a part of Eastern Black Sea Basin. Perimeter of the basin, the ratio of the basin perimeter to the main stream length of the same basin, the drainage frequency, the mean slope of basin, v the mean annual precipitation and the curve number are the parameters that have been analysed for the multilinear statistical model. Principal Component Analysis, Multiple Regression Analysis and Stepwise Regression Analysis have been run for the data sets. For the computed discharges validation has been done. As a result of validation, it has been seen that the stepwise regression gives much closer discharge values to the observed values than the multiple regression results.

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Jenkins, Gareth. "An investigation of marine influence during deposition of the Lower Old Red Sandstone, Anglo-Welsh Basin, UK." Thesis, Cardiff University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.287490.

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Langa, Sílvia da Fátima. "The impact and control of waterweeds in the Southern Mozambique Basin rivers." Thesis, Rhodes University, 2013. http://hdl.handle.net/10962/d1001905.

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In Mozambique, establishment of aquatic weeds has been enhanced through the increased enrichment of water bodies by nutrient runoffs from human and agricultural wastes that lead to an increase in nitrate and phosphate in the water. The aquatic weeds, water hyacinth (Eichhornia crassipes), red water fern ( Azolla microphylla), water lettuce (Pistia stratiotes) and salvinia (Salvinia molesta) were found in most watercourses in Mozambique and are becoming aggressive in some watercourses, especially in the Umbeluzi and Incomati rivers. Farmers and people living along the rivers are aware of the negative impact of the water weeds because the large mats of weeds cause loss of shoreline and navigability along the rivers. Other commonly perceived effects of aquatic invasive plants in Mozambique rivers include: reduced navigable surface area; difficulties for fishermen, which reduces income; increased prevalence of insects and insect-borne disease, and decreased aesthetic value. The methods currently used for the control and management of the aquatic weeds are mechanical and manual control. Both methods are costly, time consuming, and only provide a short-term solution to the problem. The study found that the weevils Neochetina eichhorniae and N. bruchi were effective biological control agents in the study area but their impact is too gradual compared to the aggressive proliferation of water hyacinth. The one year lab-experiment clearly demonstrated that the water lettuce weed had a significant impact on the recruitment of macro-invertebrates to the artificial substrates, and water lettuce contributed to the reduction of oxygen in the water and consequent reduction of macro-invertebrate abundance and diversity. The biodiversity recovered at the same time in the pools containing water lettuce controlled by N. affinis and water lettuce controlled by herbicide, but richness and diversity of macro-invertebrates was higher in the water lettuce controlled by N affinis during the first sampling occasion compared to the water lettuce in pools controlled by herbicide, where macro-invertebrates increased only when DO levels recovered after water lettuce mat decay. The number of taxa recorded in this study is an indication of the significance of macro-invertebrates in an aquatic environment. This therefore emphasizes the need for more research efforts into macrophyte and macro-invertebrate associations in the aquatic system to better understand the implications of habitat modification arising from human activities. It will also enable us to be better equipped with a more appropriate ecological understanding for aquatic resources management.

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Danner, Constance L. "Documentation and testing of the WEAP model for the Rio Grande/Bravo Basin." Thesis, (4 MB), 2006. http://handle.dtic.mil/100.2/ADA471843.

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Thesis (M.S. in Engineering)--University of Texas at Austin, 2006.
"August 2006." Description based on title screen as viewed on June 1, 2010. DTIC Descriptor(s): Computer Programs, Ground Water, Basins (Geographic), Computerized Simulation, Volume, Water Flow, Reservoirs, Mexico, North America, Streams, Banks (Waterways), Models, Physical Properties, Theses. DTIC Identifier(s): Rio Grande/Bravo Basin, Water Evaluation and Planning System, WEAP (Water Evaluation and Planning System), Weap Model, IBWC (International Boundary and Water Commission). Includes bibliographical references (p. 39-41). Also available in print.

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Hewitt, Jack. "Factors Controlling Mercury Concentration in Rivers in the Mackenzie River Basin, Northwestern Canada." Thesis, Uppsala universitet, Luft-, vatten- och landskapslära, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-414036.

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Mercury (Hg) in rivers and streams of the Mackenzie River Basin (MRB) presents a risk to fish, aquatic mammals, and humans. This thesis makes use of newly-released water quality data, including total mercury (THg) and dissolved mercury (DHg), gathered through the NWT-Wide Community-based Water Quality Monitoring (CBM) program. Landscape metrics extracted from geospatial datasets (e.g. vegetation type cover and ground ice presence), along with the water quality parameters were transformed, as needed, and then assessed for relationships with Hg concentration in rivers using principle component analysis, correlation and linear regression. Transformed turbidity, total phosphate, total sulfate, and the 1st principle component representing total metals were positively correlated with log10 THg and log10 particulate Hg (PHg) (p < 0.05) in major tributaries on the MRB. Major tributaries had a greater proportion of THg as PHg. Dissolved organic carbon and total organic carbon were positivity correlated to log10 DHg in minor tributaries (p < 0.05) of the MRB. Logit-transformed ground ice presence was positively correlated with median log10 PHg and log10 THg (PHg; p < 0.05, THg; p < 0.05). Median log10 DHg was positively correlated with logit-transformed landcover metric mixed forest (R2 = 0.67), and negativity correlated with logit-transformed landcover metric sub-polar taiga needleleaf forest (R2 = 0.64) (p < 0.05). This suggests suspended particles, derived potentially from suspended mineral matter, kerogens, and/ or weathering of sulfides could be a control on PHg in major tributaries of the MRB, while thicker, organic soils, potentially in forested areas, releasing TOC and DOC, could control export of DHg to minor tributaries in the MRB.

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Baggiano, Olivier. "The Murray - Darling Turtles: Gene Flow and Population Persistance in Dryland Rivers." Thesis, Griffith University, 2012. http://hdl.handle.net/10072/367471.

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Australia’s largest and most important waterway- the Murray-Darling Basin (MDB) - is under threat owing to predicted increases in temperature extremes and reduction in rainfall - runoff in the coming decades. Management strategies are required that incorporate an understanding of dispersal patterns of the MDB fauna and flora. Patterns of dispersal have typically been studied through direct organismal studies but genetic approaches, in which the movement of genes in the landscape is used as a correlate of species dispersal, can provide a more comprehensive view by investigating at a much larger temporal and spatial scale. Genetic connectivity (dispersal) is influenced by the biology of the species, and by flow regime and the dendritic pattern of the network in riverine landscapes. An understanding of the relative influence of each on connectivity is required to deliver informed management strategies. Decisions regarding whether management for conservation is necessary also require an understanding of a species susceptibility to a changing environment. Species already exhibiting deleterious trajectories under current flow regimes in the basin may require more drastic measures than those that have remained unaffected.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Environment
Science, Environment, Engineering and Technology
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King, Alison Jane 1974. "Recruitment ecology of fish in floodplain rivers of the southern Murray-Darling Basin, Australia." Monash University, Dept. of Biological Sciences, 2002. http://arrow.monash.edu.au/hdl/1959.1/8391.

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20

Summerside, Scott Evan. "Systems analysis of upper San Pedro River Basin conflicts." Thesis, The University of Arizona, 1991. http://hdl.handle.net/10150/192127.

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A potential for conflict exists over water management and allocation in the Upper San Pedro River Basin. Competing demands for limited water supplies have resulted in concerns about the depletion of the ground-water supplies, reductions in stream flow, and downstream obligations associated with the Gila River Adjudication. A network flow model is an effective tool for analyzing the nature of these water conflicts and evaluating how the introduction of new management strategies can ameliorate the problems. Analysis of water management reveals that concerns about the water problems are valid. Irrigation wells pumping ground water from the floodplain aquifer reduce stream flows that are both necessary for the viability of San Pedro riparian ecosystem, and claimed by downstream Indian tribes. They also contribute to the ground-water overdraft situation in the regional aquifer. Water management alternatives that limit or reduce irrigation consumption are the most effective in rectifying the problems.

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21

Franzoia, Mariateresa. "Sediment yield in rivers at different time-scales." Doctoral thesis, Università degli studi di Padova, 2014. http://hdl.handle.net/11577/3423550.

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The present thesis is devoted to a particular topic regarding the fluvial sub-systems, namely the evaluation of the annual amount of sediment yield through a given cross-section of a river. This problem has been largely investigated in literature and the resulting models can be classify in different groups depending on the morphological characteristics they take into account and their complexity. In any case the large quantity of data required is always the main problem. With this work we want to find simple relationships that require the lesser number of data as possible, so we have made our evaluations at a basin-scale and assumed for the river the Local Uniform Flow hypothesis (LUF). Accordingly, each river reach is defined by its length, width, slope and bottom composition, while the watershed area is collapsed in its barycentre which coincides with the upstream end of the LUF reach. A basic state, called equilibrium and represented by a stationary rating curve (a monomial relation between the solid and the liquid discharge of Engelund-Hansen type) is first identified, with the purpose to evaluate the deviations of the real solid transport from the equilibrium value, deviations that depend on the time-scale considered. In particular we have developed three models, valid in three different time-scales. For the short-term analysis we use the 1-D deterministic solution of the harmonic river which provides the delay and attenuation of the perturbation of the solid transport with respect to the equilibrium condition. In other words we link the actual deviations of the solid transport recorded downstream with previous perturbations of the liquid discharge, happened upstream. For a pluri-annual time-scale we integrate the 1-D morphodynamic model to a zero-dimensional model. As the water and sediments inputs to the river are concentrated in its upstream end, the width of the entire river is assumed to be constant, while the slope and the grain-size composition are considered to be variable in time. The resulting mathematical model is implicit and non-linear, but at this time-scale we simplify it in order to find a simple and generic analytical solution for the pluri-annual morphological evolution of the river. Finally, for very long-term analysis we integrate numerically the exact 0-D morphodynamic model to predict the morphological reactions of a river at geological time-scale. In this case we schematize the river with two contiguous LUF channel, representing the highland and the lowland parts of the real watercourse respectively. In this way, this model can simulate the typical behaviour of natural rivers showing a grain-size segregation (fining) in the downstream direction, accompanied by smaller slopes, without the computational costs necessary for a complete one-dimensional model. Some comparisons and numerical applications have been made.
Questa tesi è dedicata ad un tema particolare che riguarda i sotto-sistemi fluviali, vale a dire la valutazione dell'importo annuo di produzione di sedimenti attraverso una determinata sezione fluviale. Questo problema è stato ampiamente studiato in letteratura e i modelli sviluppati possono essere classificati in diversi gruppi a seconda delle caratteristiche morfologiche di cui tengono conto e della loro complessità. In ogni caso, il problema principale è sempre la grande quantità di dati richiesti. Con questo lavoro vogliamo trovare delle semplici relazioni che richiedano il minor numero di dati possibile, per questo abbiamo sviluppato le nostre valutazioni ad una scala spaziale di bacino ed assunto per il fiume l'ipotesi flusso localmente uniforme (LUF). Di conseguenza ogni tratto fluviale è definito dalla sua lunghezza, dalla larghezza, dala pendenza e dalla composizione granulometrica del fondo, mentre l'estremità a monte del canale LUF coincide col baricentro del bacino in cui si assume sia concentrata l'intera area. Prima si identifica una condizione di base, chiamata di equilibrio e rappresentata da una curva stazionaria (una relazione monomia tra le portate solida e liquida di tipo Engelund-Hansen), con lo scopo di valutare le deviazioni del trasporto solido reale dal valore di equilibrio, deviazioni che dipendono dalla scala temporale considerata. In particolare abbiamo sviluppato tre modelli, validi per tre diverse scale temporali. Per l'analisi a breve termine usiamo la soluzione deterministica armonica 1-D del fiume, che fornisce il ritardo e l'attenuazione della perturbazione del trasporto solido rispetto alla condizione di equilibrio. In altre parole, colleghiamo le deviazioni effettive del trasporto solido registrate a valle con le precedenti perturbazioni della portata liquida avvenute a monte. Per una scala pluriannuale integriamo il modello morfodinamica 1-D ad un modello zero-dimensionale. Dato che gli ingressi di acqua e sedimenti al fiume sono concentrati alla sua estremità a monte, la larghezza dell'intero fiume è ipotizzata costante, mentre la pendenza e la composizione granulometrica sono considerate essere variabili nel tempo. Ne risulta un modello matematico implicito e non lineare, ma a questa scala temporale lo possiamo semplificare al fine di trovare una soluzione analitica semplice e generica per l'evoluzione morfologica pluriennale del fiume. Infine, per un'analisi a lungo termine integriamo numericamente il modello morfodinamico 0-D esatto per valutare le reazioni morfologiche di un fiume a scala temporale geologica. In questo caso si schematizza il fiume con due canali LUF contigui, che rappresentano rispettivamente il tratto montano e e il tratto di pianura del reale corso d'acqua. In questo modo, questo modello può simulare il comportamento tipico dei fiumi naturali mostrando una differenziazione granulometrica (affinamento) verso valle accompagnata da pendenze minori, senza i costi computazionali necessari per un modello unidimensionale completo. Sono stati fatti alcuni confronti e applicazioni numeriche.

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22

Silveira, André Filipe. "Polycentricity and the adaptive capacity of river basin governance systems : insights from the River Rhine and the Pearl River (Zhujiang)." Thesis, University of Cambridge, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.708546.

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23

Gibbs, Helen Margaret. "The interactions between macrophytes and sediments in urban river systems." Thesis, Queen Mary, University of London, 2013. http://qmro.qmul.ac.uk/xmlui/handle/123456789/8480.

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Many urban rivers receive significant inputs of metal-contaminated sediments from their catchments. Their restoration has the potential to increase the deposition and accumulation of these sediments from greater sediment supply and increased channel hydraulic complexity, creating a store of metals which could have negative impacts upon ecosystems and human health. Macrophytes often establish in restored channels and have the potential to stabilise these sediments and uptake metals through processes of phytoremediation, thus reducing the risk of the accumulated sediments becoming a source of metals. This thesis investigates the effects of river restoration upon sedimentation patterns and the interactions between macrophytes and sediments in terms of sediment trapping, stabilisation and metal uptake within urban river systems. At a reach scale, greater finer sediment deposition and the accumulation of sediment around in-channel vegetation was found within restored stretches of tributaries of the River Thames London, reflecting sediment availability and hydraulic conditions. These sediments were important in terms of greater metal storage within stretches, and along with gravels showed particularly high metal concentrations. Interactions between macrophytes, sediment and flow were investigated within the urban-influenced River Blackwater, Surrey. At the stand scale, the common emergent Sparganium erectum was found to significantly reduce flow velocities, accumulate fine sediments and retain them over winter. Research on individual plants revealed that, although three common emergent macrophytes (Sparganium erectum, Typha latifolia and Phalaris arundinacea) did not significantly phytoremediate metal contaminated sediments through metal uptake or bioconcentration, the reinforcement and stabilisation of these accumulated sediments (particularly by Sparganium erectum and Typha latifolia) and the creation of anoxic sediment conditions which strongly bind metals, were important in reducing the risk of metal mobilisation from the sediments. These macrophyte sediment interactions illustrate the great potential of using emergent macrophytes in the restoration and management of urban rivers with metal contaminated sediments.

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24

Osei-Twumasi, Anthony. "Integrated modelling studies of solute transport in river basin systems." Thesis, Cardiff University, 2010. http://orca.cf.ac.uk/54991/.

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Surface water and groundwater systems are linked dynamically in reality as the one generally impacts directly on the other. Traditionally, however, these two water bodies have more often than not been treated as different entities by water managers and other professionals. The issue of the compartmentality of these two resources is the main focus of the study described herein. In this study, an existing 1D-2D hydro-environmental surface water model that includes a groundwater model (DIVAST-SG) has been extended to 2-D and refined through testing against three laboratory studies. A surface water-groundwater system model using foam to replicate groundwater material was created in the laboratory and the results of the hydrodynamic processes (i.e. water elevations and flowpaths) were compared with the numerical model predictions. On the whole the comparisons showed good agreement. However, dye studies for replicating pollutant transport did not show such good agreement and this discrepancy was thought to be due to a number of reasons. In the second series of studies, the groundwater material was then replaced with the more traditional sand embankment and again results for both hydrodynamic and solute transport processes (by way of dye studies) from the laboratory set up were compared with the numerical predictions which were in almost perfect agreement. In the same tidal basin, a Severn Estuary model was then designed and set up. Although there were differences from the prototype owing to space and scaling difficulties, the results showed good agreement for both tidal amplitudes and tidal currents with the predictions from the numerical model and particularly the tidal amplitudes were found to compare favourably with field studies. Tracer results from the physical model also showed consistency with simulations from previous researchers in the main estuary. Overall, the purpose of this study, which was to investigate the manner in which flow and solute (conservative tracer) fluxes interacted between surface and sub-surface flows, for simulated riverine and tidal conditions, has been achieved. These experiments and the corresponding datasets are thought to be unique.

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25

Hoeinghaus, David Joseph. "Food web architecture in natural and impounded rivers of the Upper Parana drainage basin, Brazil." Diss., Texas A&M University, 2006. http://hdl.handle.net/1969.1/4845.

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Freshwater ecosystems are some of the most threatened on the planet. Efforts to conserve, restore, or otherwise manage large rivers and the services they provide are hindered by limited understanding of the functional dynamics of these systems. This shortcoming is especially evident with regard to trophic structure and energy flow. In this study I use natural abundances of carbon and nitrogen isotopes to examine patterns of energy flow and food-chain length of large-river food webs characterized by different landscape-scale hydrologic features. Ten locations along an approximately 500 km stretch of the Upper ParanÃÂ¡ River Basin, Brazil, provided the setting for this work. Carbon derived from C3 plants and phytoplankton were the dominant energy sources across all webs, but relative contributions differed among landscape types (low-gradient river, high-gradient river, river stretches downstream of reservoirs, and reservoirs). Increases in food chain length corresponded with higher relative importance of phytoplankton derived carbon, likely due to size-structured effects of the phytoplankton-zooplankton-secondary consumer trophic link. River impoundment corresponded with decreased ecological and economic efficiency of fisheries production, an important ecosystem service provided by many tropical rivers.

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26

Kneis, David. "A water quality model for shallow river lake systems and its application in river basin management." Phd thesis, [S.l.] : [s.n.], 2007. http://opus.kobv.de/ubp/volltexte/2007/1464.

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27

Gomes, Daniel Dantas Moreira. "Gis applied to analysis and zoning systems environment of the river MundaÃ River Basin - PE / AL." Universidade Federal do CearÃ, 2015. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=17248.

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CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior
Given the population growth, technological development and the increasing demand for natural resources becomes clear the importance of the rational and sustainable use of these resources, mainly in the Northeast region of Brazil, which has a major imbalance between supply and demand water and suffer with various problems related to inappropriate land use. Analysis and zoning of different environmental systems, aided by geoprocessing tools, serve as input for land use planning, allowing knowledge and a better use of the potential environmental and reducing the negative effects caused by the inappropriate use of natural resources. Noting the foregoing, it is intended to carry out an analysis and zoning of environmental systems in the watershed of the MundaÃ River (BHRM) - Pernambuco / Alagoas using geoprocessing and empirical models for determination of environmental vulnerability, identifying the main negative environmental impacts and propose a Geoenvironmental zoning model of the study area. The thesis is organized into seven sections, the first section presents the introduction of the research, justifying the relevance of the subject, exposing the thesis objectives, the organizational structure of the same, the literature review and theoretical foundations, and finally is held a demonstration of the technical and methodological procedures. The second section seeks to assess the morphometry of the basin of the MundaÃ River, at this stage, the morphometric characteristics were grouped according to their properties: linear analysis, areal analysis and hypsometric analysis, where the linear attributes involve the drainage network and its spatial arrangement in the basin. To detail the study was considered the characterization of the basin of the MundaÃ River and its sub-basins where each was analyzed individually. The third section was elaborated the mapping and characterization of geomorphic units of the watershed of the MundaÃ River, interpreting the relief forms using different scales of identification and analysis. The elaborate geomorphological compartmentation considers the first four taxonomic levels of relief, where the morphogenetic processes and morphodynamics of the river basin were observed. In the fourth section was prepared mapping coverage and land use in the watershed study, serving as a planning tool and guidance for decision-making. On Thursday seeks to assess section, with the help of GIS techniques, environmental systems in the mentioned river basin, from the systematization and the interrelationship that exists between society and nature from the perspective of rational use of Geoenvironments, taking into account the capabilities and vulnerabilities. The sixth section we sought to establish a proposal for environmental zoning, using empirical models, through interpretation of remote sensing products and field analysis. Finally in the seventh section are made final thesis considerations.
Tendo em vista o aumento populacional, o desenvolvimento tecnolÃgico e a crescente demanda pelos recursos naturais torna-se clara a importÃncia do uso racional e sustentÃvel desses recursos, principalmente para a regiÃo Nordeste do Brasil, que apresenta um grande desequilÃbrio entre a oferta e a demanda de Ãgua, alÃm de sofrerem com diversos problemas relacionados ao uso inapropriado do solo. A anÃlise e zoneamento de diferentes sistemas ambientais, auxiliados pelos usos de ferramentas de geoprocessamento, servem como subsÃdio para um ordenamento territorial, permitindo um conhecimento e um melhor aproveitamento das potencialidades ambientais e diminuindo os efeitos negativos ocasionados pelo uso inadequado dos recursos naturais. Observando o que foi exposto, pretende-se realizar uma anÃlise e zoneamento dos sistemas ambientais na bacia hidrogrÃfica do Rio MundaÃ (BHRM) â Pernambuco/Alagoas, utilizando tÃcnicas de geoprocessamento e modelos empÃricos para determinaÃÃo da vulnerabilidade ambiental, identificaÃÃo os principais impactos ambientais negativos e propor um modelo de zoneamento geoambiental da Ãrea em estudo. A tese estÃ organizada em sete seÃÃes, na primeira seÃÃo apresenta-se a introduÃÃo da pesquisa, justificando a relevÃncia do tema, expondo os objetivos da tese, a estrutura de organizaÃÃo da mesma, a revisÃo de literatura e fundamentaÃÃes teÃricas, e por fim Ã realizada uma demonstraÃÃo dos procedimentos tÃcnicos e metodolÃgicos. A segunda seÃÃo busca avaliar a morfometria da bacia hidrogrÃfica do Rio MundaÃ, nessa etapa, as caracterÃsticas morfomÃtricas foram agrupadas segundo suas propriedades em: anÃlise linear, anÃlise areal e anÃlise hipsomÃtrica, onde os atributos lineares envolvem a rede de drenagem e seu arranjo espacial dentro da bacia. Para detalhar o estudo foi considerada a caracterizaÃÃo da bacia do Rio MundaÃ e suas sub-bacias, onde cada uma foi analisada individualmente. A terceira seÃÃo elaborou-se o mapeamento e caracterizaÃÃo das unidades geomorfolÃgicas da bacia hidrogrÃfica do Rio MundaÃ, interpretando as formas do relevo utilizando diferentes escalas de identificaÃÃo e anÃlise. A compartimentaÃÃo geomorfolÃgica elaborada considera os quatros primeiros nÃveis taxonÃmicos de relevo, onde foram observados os processos morfogenÃticos e a morfodinÃmica da bacia hidrogrÃfica. Na quarta seÃÃo foi elaborado o mapeamento da cobertura e do uso da terra da bacia hidrogrÃfica em estudo, servindo como ferramenta de planejamento e de orientaÃÃo Ã tomada de decisÃo. Na quinta seÃÃo busca-se avaliar, com o auxÃlio das tÃcnicas de geoprocessamento, os sistemas ambientais na mencionada bacia hidrogrÃfica, a partir da sistematizaÃÃo e da inter-relaÃÃo que se dÃ entre Sociedade-Natureza na perspectiva do uso racional dos geoambientes, levando em consideraÃÃo as potencialidades e vulnerabilidades. A sexta seÃÃo buscou-se estabelecer uma proposta de zoneamento ambiental, utilizando modelos empÃricos, atravÃs de interpretaÃÃo de produtos de sensoriamento remoto e anÃlise de campo. E por fim na sÃtima seÃÃo sÃo feitas as consideraÃÃes finais da tese.

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28

Redolfi, Marco. "Sediment transport and morphology of braided rivers : steady and unsteady regime." Thesis, Queen Mary, University of London, 2015. http://qmro.qmul.ac.uk/xmlui/handle/123456789/8857.

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Braided rivers are complex, fascinating fluvial pattern, which represent the natural state of many gravel and sand bed rivers. Both natural and human causes may force a change in the boundary conditions, and consequently impact the river functionality. Detailed knowledge on the consequent morphological response is important in order to define management strategies which combine different needs, from protection of human activities and infrastructures to preservation of the ecological and biological richness. During the last decades, research has made significant advance to the description of this complex system, thanks to flume investigations, development of new survey techniques and, to a lesser extent, numerical and analytical solutions of mathematical models (e.g. Ashmore, 2013). Despite that, many relevant questions, concerning the braided morphodynamics at different spatial and temporal scales (from the unit process scale, to the reach scale, and eventually to the catchment scale) remain unanswered. For example, quantitative analysis of the morphological response to varying external controls still requires investigation and needs the definition of suitable, stage-independent braiding indicators. In addition, the morphodynamics of the fundamental processes, such as bifurcations, also needs further analysis of the driving mechanisms. General aim of the present study is to develop new methods to exploit, in an integrated way, the potential of the new possibilities offered by advanced monitoring techniques, laboratory models, numerical schemes and analytical solutions. The final goal is to fill some gaps in the present knowledge, which could ultimately provide scientific support to river management policies. We adopted analytical perturbation approaches to solve the two-dimensional shallow water model; we performed laboratory simulations on a large, mobilebed flume; we analysed existing topographic measurements from LiDAR and Terrestrial Laser scanning Devices; and we simulated numerically the river hydrodynamics. Within each of the six, independent, research chapters, we interconnected results from the different approaches and methodologies, in order to take advantage of their potential. Summarising, the more relevant and novel outcomes of the present work can be listed as follows:(i) We explored the morphological changes during a sequence of flood events in a natural braided river (Rees River, NZ) and we proposed a morphological method to assess the sediment transport rate. In particular we propose a semi-automatic method for estimating the particles path-length (Ashmore and Church, 1998) on the basis of the size of the deposition patches, which can be identified on the basis of DEM of differences. Comparison with results of numerical simulation confirmed that such an approach can reproduce the response of the bedload rate to floods of different duration and magnitude. (ii) We developed a new indicator of the reach-scale morphology and, on the basis of existing laboratory experiments, we explored its dependence, under regime conditions, to the controlling factors: slope, discharge, confinement width, grain size. In spite of its synthetic nature, this simple indicator embeds the information needed to estimate the variability of the Shield stress throughout the braided network, and consequently enables to assess the transport-rate and its variation with the driving discharge. (iii) We investigated, through flume experiments, the effect of the flow unsteadiness on the sediment transport in a braided river. This is possible only by following a statistical approach based on multiple repetitions of the same flow hydrograph. Results revealed that for confined network an hysteresis of the bedload response occurs, which leads to higher sediment transport during increasing flow, whereas relatively unconfined networks always show quasi-equilibrium transport rates. (iv) A second set of laboratory experiments provided information on the morphodynamics of a braided network subject to variations of the sediment supply. We proposed a simple diffusive model to quantify the evolution of the one-dimensional bed elevation profile. Such simple approach, albeit having a limited range of practical applications, represents the first attempt to quantify this process and enables to study the relevant temporal and spatial scales of the phenomenon. (v) We solved analytically the two-dimensional morphodynamic model for a gravel-bed river bifurcation. This furnishes a rigorous proof to the idea proposed by Bertoldi and Tubino (2007) to interpret the morphological response of bifurcation in light of the theory of the morphodynamic influence. The analytical approach enables to investigate the fundamental mechanics which leads to balance, and unbalance, configurations and, from a more practical point of view, allows for a better prediction of the instability point than the existing 1D models (e.g. Bolla Pittaluga et al., 2003).

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29

Carini, Giovannella, and n/a. "Effects of Contemporary and Historical Processes on Population Genetic Structure of Two Freshwater Species in Dryland River Systems (Western Queensland, Australia)." Griffith University. Australian School of Environmental Studies, 2004. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20050113.081250.

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Arid and semiarid river systems in Western Queensland, Australia, are characterized by the unpredictable and highly variable nature of their hydrological regimes as a result of the episodic nature of rain events in the region. These dryland rivers typically experience episodic floods and extremely low or no flow periods. During low or no flow periods, water persists only in relatively wide and deep sections of the river channels, which are called 'waterholes'. These isolated waterholes serve as refugia for aquatic species during protracted intervals between floods. In such discontinuous riverine habitat, dispersal of freshwater species may be achieved only during wet seasons, when water is flowing in rivers and the nearby floodplains. Obligate aquatic species occur in habitats that represent discrete sites surrounded by inhospitable terrestrial landscapes. Thus, movements are very much limited by the physical nature and arrangement of the riverine system. In addition, the distribution of a species may be also largely dependent on historical events. Landscape and river courses continually change over geological time, often leaving distinct phylogenetic 'signatures', useful in reconciling species' biology with population connectivity and earth history. The main aim of this study was to resolve the relative importance of contemporary and historical processes in structuring populations of two freshwater species in Western Queensland river systems. To address this aim, a comparative approach was taken in analysing patterns of genetic variation of two freshwater invertebrates: a snail (Notopala sublineata) and a prawn (Macrobrachium australiense). Mitochondrial sequences were used for both the species. In addition, allozyme and microsatellites markers were employed for N. sublineata. These species have similar distributions in Western Queensland region, although N. sublineata appears to be extinct in some catchments. M. australiense is thought to have good dispersal abilities due to a planktonic larval phase in its life cycle and good swimming capabilities, whereas N. sublineata is thought to have limited dispersal abilities, because of its benthic behaviour and because this species is viviparous. It was hypothesised that these freshwater invertebrates, would display high levels of genetic structure in populations, because physical barriers represented by terrestrial inhospitable habitat, are likely to impede gene flow between populations inhabiting isolated river pools. Genetic data for the two species targeted in this study supported this hypothesis, indicating strong population subdivision at all spatial scales investigated (i.e. between and within catchments). This suggests that contemporary dispersal between isolated waterholes is relatively restricted, despite the potential good dispersal abilities of one of the species. It was hypothesised that levels of gene flow between populations of aquatic species were higher during the Quaternary (likely movements of individuals across catchment boundaries) and that they have been isolated relatively recently. There is evidence that historically gene flow was occurring between populations, suggesting that episodic dispersal across catchment boundaries was likelier in the past. Episodic historical movements of aquatic fauna were facilitated by higher patterns of river connectivity as a result of the climate changes of the Pleistocene. Because the two species targeted in this study exhibit analogous spatial patterns of evolutionary subdivision it is likely that they have a shared biogeographic history. The unpredictable flow regime of rivers in Western Queensland is likely to have considerable effects on the genetic diversity of aquatic populations. First, if populations of obligate freshwater organisms inhabiting less persistent waterholes are more likely to experience periodic bottlenecks than those inhabiting more persistent ones, they would be expected to have lower levels of genetic diversity. Second, if populations inhabiting less persistent waterholes periodically undergo local extinction with subsequent recolonisation, there should be higher levels of genetic differentiation among them, due to the founder effects, than among those populations inhabiting more persistent waterholes. Contrary to the first prediction, the observed levels of genetic diversity in both N. sublineata and M. australiense were high in both more persistent and less persistent waterholes. There was no tendency for genetic diversity to be lower in less persistent than in more persistent waterholes. However, when Cooper waterholes were ranked in order of persistence, positive correlation between water persistence time in waterholes and genetic diversity was detected in N. sublineata but not in M. australiense. Contrary to the second prediction, highly significant genetic differentiation was found among populations from both less persistent and more persistent waterholes. This indicates that not only populations from less persistent but also those from more persistent waterholes were very dissimilar genetically. This study demonstrated the importance of both contemporary and historical processes in shaping the population structure of obligate freshwater species in Western Queensland river systems. It has indicated that contemporary movements of freshwater species generally are extremely limited across the region, whereas episodic dispersal across catchment boundaries was possible during the Pleistocene, due to different patterns of river connectivity.

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30

Carini, Giovannella. "Effects of Contemporary and Historical Processes on Population Genetic Structure of Two Freshwater Species in Dryland River Systems (Western Queensland, Australia)." Thesis, Griffith University, 2004. http://hdl.handle.net/10072/367070.

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Abstract:

Arid and semiarid river systems in Western Queensland, Australia, are characterized by the unpredictable and highly variable nature of their hydrological regimes as a result of the episodic nature of rain events in the region. These dryland rivers typically experience episodic floods and extremely low or no flow periods. During low or no flow periods, water persists only in relatively wide and deep sections of the river channels, which are called 'waterholes'. These isolated waterholes serve as refugia for aquatic species during protracted intervals between floods. In such discontinuous riverine habitat, dispersal of freshwater species may be achieved only during wet seasons, when water is flowing in rivers and the nearby floodplains. Obligate aquatic species occur in habitats that represent discrete sites surrounded by inhospitable terrestrial landscapes. Thus, movements are very much limited by the physical nature and arrangement of the riverine system. In addition, the distribution of a species may be also largely dependent on historical events. Landscape and river courses continually change over geological time, often leaving distinct phylogenetic 'signatures', useful in reconciling species' biology with population connectivity and earth history. The main aim of this study was to resolve the relative importance of contemporary and historical processes in structuring populations of two freshwater species in Western Queensland river systems. To address this aim, a comparative approach was taken in analysing patterns of genetic variation of two freshwater invertebrates: a snail (Notopala sublineata) and a prawn (Macrobrachium australiense). Mitochondrial sequences were used for both the species. In addition, allozyme and microsatellites markers were employed for N. sublineata. These species have similar distributions in Western Queensland region, although N. sublineata appears to be extinct in some catchments. M. australiense is thought to have good dispersal abilities due to a planktonic larval phase in its life cycle and good swimming capabilities, whereas N. sublineata is thought to have limited dispersal abilities, because of its benthic behaviour and because this species is viviparous. It was hypothesised that these freshwater invertebrates, would display high levels of genetic structure in populations, because physical barriers represented by terrestrial inhospitable habitat, are likely to impede gene flow between populations inhabiting isolated river pools. Genetic data for the two species targeted in this study supported this hypothesis, indicating strong population subdivision at all spatial scales investigated (i.e. between and within catchments). This suggests that contemporary dispersal between isolated waterholes is relatively restricted, despite the potential good dispersal abilities of one of the species. It was hypothesised that levels of gene flow between populations of aquatic species were higher during the Quaternary (likely movements of individuals across catchment boundaries) and that they have been isolated relatively recently. There is evidence that historically gene flow was occurring between populations, suggesting that episodic dispersal across catchment boundaries was likelier in the past. Episodic historical movements of aquatic fauna were facilitated by higher patterns of river connectivity as a result of the climate changes of the Pleistocene. Because the two species targeted in this study exhibit analogous spatial patterns of evolutionary subdivision it is likely that they have a shared biogeographic history. The unpredictable flow regime of rivers in Western Queensland is likely to have considerable effects on the genetic diversity of aquatic populations. First, if populations of obligate freshwater organisms inhabiting less persistent waterholes are more likely to experience periodic bottlenecks than those inhabiting more persistent ones, they would be expected to have lower levels of genetic diversity. Second, if populations inhabiting less persistent waterholes periodically undergo local extinction with subsequent recolonisation, there should be higher levels of genetic differentiation among them, due to the founder effects, than among those populations inhabiting more persistent waterholes. Contrary to the first prediction, the observed levels of genetic diversity in both N. sublineata and M. australiense were high in both more persistent and less persistent waterholes. There was no tendency for genetic diversity to be lower in less persistent than in more persistent waterholes. However, when Cooper waterholes were ranked in order of persistence, positive correlation between water persistence time in waterholes and genetic diversity was detected in N. sublineata but not in M. australiense. Contrary to the second prediction, highly significant genetic differentiation was found among populations from both less persistent and more persistent waterholes. This indicates that not only populations from less persistent but also those from more persistent waterholes were very dissimilar genetically. This study demonstrated the importance of both contemporary and historical processes in shaping the population structure of obligate freshwater species in Western Queensland river systems. It has indicated that contemporary movements of freshwater species generally are extremely limited across the region, whereas episodic dispersal across catchment boundaries was possible during the Pleistocene, due to different patterns of river connectivity.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Australian School of Environmental Studies
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Wong, Wing-sze, and 黃穎詩. "Water chemistry in the Kam Tin basin, natural and authropogenic influences." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B38605843.

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Karaaslan, Huseyin Nail. "Estimation Of Specific Flow Duration Curves Using Basin Characteristics Of Rivers In Solakli And Karadere Basins." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12612873/index.pdf.

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Demand for energy is constantly growing both in the world and in Turkey. Sustainable development being an important concept, development of small hydro power projects has been popular in recent years. Eastern Black Sea Basin in Turkey has a lot of small hydro power potential because of high amount of precipitation and existence of steep slopes. Since the amount of river runoff is the only parameter that is variable in order to determine the power potential, it is vital to estimate the project discharge in ungauged basins accurately that have hydro power potential. Projects discharges of hydro-power plants in ungauged basins have been calculated using conventional methods up to now. This study aims to introduce a statistical model in linear and multi-variate form using the topographical and morphological parameters derived from GIS and hydro-meteorological variables to estimate the specific flow duration curves of potential small hydro-power locations for the selected study areas in Eastern Black Sea Region namely Solakli and Karadere basins. As well as developing an annual regression model using the annual values of hydro-meteorological parameters
seasonal regression model (spring season) has also been developed by including the mean seasonal (spring) air temperature variable instead of snow covered area (SCA) in addition to basin parameters. By studying the spring model, effect of different variables from the annual model were tested and discussed with some recommendations for the future studies.

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Lunn, Rebecca Jane. "A nitrogen modelling system for large river basins." Thesis, University of Newcastle Upon Tyne, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.294852.

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Kerr, Daniel Ernest. "Late quaternary stratigraphy and depositional environments in the basin of the Richardson and Rae Rivers, N.W.T." Thesis, University of Ottawa (Canada), 1986. http://hdl.handle.net/10393/4773.

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Su, Van-Anh. "Promoting Cooperation for the Sustainable Development of International Rivers: A Study of the Mekong River Basin." Scholarship @ Claremont, 2013. http://scholarship.claremont.edu/cmc_theses/647.

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The Mekong River is a crucial shared resource that flows through China, Myanmar, Laos, Thailand, Cambodia, and Vietnam. Over 80 million people have traditionally depended on the river to sustain their livelihoods. However, recent large-scale dam projects present serious consequences to the environmental security of the riparian states. In particular, dam construction by upstream countries poses negative socioeconomic and environmental externalities to downstream countries. Such a dynamic has incited regional tension and set a precedent for river management along national lines rather than as a collective good. Given such circumstances, this paper investigates whether the Mekong countries can transition to a cooperative regime that prioritizes the sustainable development of the river. In particular, this paper assesses the feasibility of achieving sustainable river cooperation by (i) analyzing the conditions that enable or hinder river cooperation, and (ii) investigating the extent that bargaining and benefit-sharing strategies can promote the long-term well-being of the river. The paper finds that the lack of credible commitment to the river’s sustainable development at both the regional and domestic levels renders cooperation for Mekong sustainability unlikely at this time.

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Boys, Craig Ashley, and n/a. "Fish-Habitat Associations in a Large Dryland River of the Murray-Darling Basin, Australia." University of Canberra. Resource, Environmental & Heritage Sciences, 2007. http://erl.canberra.edu.au./public/adt-AUC20070807.112943.

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Many aspects concerning the association of riverine fish with in-channel habitat remain poorly understood, greatly hindering the ability of researchers and managers to address declines in fish assemblages. Recent insights gained from landscape ecology suggest that small, uni-scalar approaches are unlikely to effectively determine those factors that influence riverine structure and function and mediate fish-habitat associations. There appears to be merit in using multiple-scale designs built upon a geomorphologically-derived hierarchy to bridge small, intermediate and large spatial scales in large rivers. This thesis employs a hierarchical design encompassing functional process zones (referred to hereafter as zones), reaches and mesohabitats to investigate fish-habitat associations as well as explore patterns of in-channel habitat structure in one of Australia's largest dryland river systems; the Barwon-Darling River. In this thesis, empirical evidence is presented showing that large dryland rivers are inherently complex in structure and different facets of existing conceptual models of landscape ecology must be refined when applied to these systems. In-channel habitat and fish exist within a hierarchical arrangement of spatial scales in the riverscape, displaying properties of discontinuities, longitudinal patterns and patch mosaics. During low flows that predominate for the majority of time in the Barwon-Darling River there is a significant difference in fish assemblage composition among mesohabitats. There is a strong association between large wood and golden perch, Murray cod and carp, but only a weak association with bony herring. Golden perch and Murray cod are large wood specialists, whereas carp are more general in there use of mesohabitats. Bony herring are strongly associated with smooth and irregular banks but are ubiquitous in most mesohabitats. Open water (mid-channel and deep pool) mesohabitats are characterised by relatively low abundances of all species and a particularly weak association with golden perch, Murray cod and carp. Murray cod are weakly associated with matted bank, whereas carp and bony herring associate with this mesohabitat patch in low abundance. Nocturnal sampling provided useful information on size-related use of habitat that was not evident from day sampling. Both bony herring and carp exhibited a variety of habitat use patterns throughout the die1 period and throughout their lifetime, with temporal partitioning of habitat use by juvenile bony herring and carp evident. Much of the strong association between bony herring and smooth and irregular banks was due to the abundance of juveniles (<100mm in length) in these mesohabitats. Adult bony herring (>100mm length) occupied large wood more than smooth and irregular banks. At night, juvenile bony herring were not captured, suggesting the use of deeper water habitats. Adult bony herring were captured at night and occupjed large wood, smooth bank and irregular bank. Juvenile carp (<200mm length) were more abundant at night and aggregated in smooth and irregular banks more than any other mesohabitat patch. Adult carp (>200mm length) occupied large wood during both day and night. There is a downstream pattern of change in the fish assemblage among river zones, with reaches in Zone 2 containing a larger proportion of introduced species (carp and goldfish) because of a significantly lower abundance of native species (bony herring, golden perch and Murray cod) than all other zones. In comparison, the fish assemblage of Zone 3 was characterised by a comparatively higher abundance of the native species bony herring, golden perch and Murray cod. A significant proportion of the amongreach variability in fish assemblage composition was explained at the zone scale, suggesting that geomorphological influences may impose some degree of top-down constraint over fish assemblage distribution. Although mesohabitat composition among reaches in the Barwon-Darling River also changed throughout the study area, this pattern explained very little of the large-scale distribution of the fish assemblage, with most of the variability in assemblage distribution remaining unexplained. Therefore, although mesohabitat patches strongly influence the distribution of species within reaches, they explain very little of assemblage composition at intermediate zone and larger river scales. These findings suggest that small scale mesohabitat rehabilitation projects within reaches are unlikely to produce measurable benefits for the fish assemblage over intermediate and large spatial scales in the Barwon-Darling River. This indicates the importance taking a holistic approach to river rehabilitation that correctly identifies and targets limiting processes at the correct scales. The variable nature of flow-pulse dynamics in the Barwon-Darling River creates a shifting habitat mosaic that serves to maintain an ever-changing arrangement of habitat patches. The inundation dynamics of large wood habitat described in this thesis highlights the fragmented nature of mesohabitat patches, with the largest proportion of total in-channel large wood remaining unavailable to fish for the majority of the time. At low flows there is a mosaic of large wood habitat and with increasing discharge more potential large wood habitat becomes available and does so in a complex spatial manner. What results in this dryland river is a dynamic pattern of spatio-temporal patchiness in large wood habitat availability that is seen both longitudinally among different river zones and vertically among different heights in the river channel. Water resource development impacts on this shifting habitat mosaic. Projects undertaking both fish habitat assessment and rehabilitation need to carefully consider spatial scale since the drivers of fish assemblage structure can occur at scales well beyond that of the reach. Fish-habitat associations occurring at small spatial scales can become decoupled by process occurring across large spatial scales, making responses in the fish assemblage hard to predict. As rivers become increasingly channelised, there is an urgent need to apply research such as that conducted in this thesis to better understand the role that in-channel habitats play in supporting fish and other ecosystem processes. Habitat rehabilitation projects need to be refined to consider the appropriate scales at which fish assemblages associate with habitat. Failure to do so risks wasting resources and forgoes valuable opportunities for addressing declines in native fish populations. Adopting multi-scalar approaches to understanding ecological processes in aquatic ecosystems, as developed in this thesis, should be a priority of research and management. To do so will enable more effective determination of those factors that influence riverine structure and function at the approariate scale.

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Sonnenberg, Rob. "Development of aquatic communities in high-altitude mine pit lake systems of west-central Alberta." Thesis, Lethbridge, Alta. : University of Lethbridge, Dept. of Geography, 2011, 2011. http://hdl.handle.net/10133/3106.

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Reclamation on the Cardinal River and Gregg River coal mines includes the construction of mine pit lakes connected to stream environments. Key physical, chemical and biological parameters of these “truck and shovel” lakes and their streams were investigated, and hypotheses regarding ecosystems and populations were tested. Findings include: Sphinx Lake and Pit Lake CD exhibit meromictic (partial-mixing) tendencies, but still function in a similar fashion to shallower, natural sub-alpine lakes. Elevated selenium concentrations as high as 16 ug/g (dry weight) were recorded in Rainbow trout (Oncorhynchus mykiss) eggs taken from gravid Sphinx Lake and Pit Lake CD fish. Potential detrimental effects associated with the bioaccumulation of selenium on fish reproduction were not observed. Stream water temperatures downstream of Sphinx Lake and Pit Lake CD were significantly warmer than in inlet streams and streams without pit lakes. Streambed concretions caused by calcite precipitation were documented and found to affect portions of the upper Gregg River basin. Remediation of this concretion is important for sustainability of trout populations. Aquatic communities including fish, invertebrates, zooplankton and aquatic plants are present in these pit lake systems. Athabasca Rainbow trout populations are self-propagating (spawning at the outlets) with higher densities downstream than there were prior to lake reclamation. The development of sub-alpine mine-pit lakes connected to the stream environment appears to be an appropriate and beneficial reclamation technique in this area.
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Germain, Richard James. "Drought management using a geographical information system." Ohio : Ohio University, 1996. http://www.ohiolink.edu/etd/view.cgi?ohiou1178651687.

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Langham, Joseph Anthony. "Self organisation in braided systems : DEM analysis of the River Feshie, Scotland." Thesis, University of Hull, 2004. http://hydra.hull.ac.uk/resources/hull:8093.

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Pulley, Simon. "Exploring fine sediment dynamics and the uncertainties associated with sediment fingerprinting in the Nene river basin, UK." Thesis, University of Northampton, 2014. http://nectar.northampton.ac.uk/7082/.

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To comply with the European Union Water Framework Directive (2000), National Governments are required to achieve good chemical and ecological status of freshwater bodies. Fine sediment has been shown to be a major cause of the degradation of lakes and rivers, and as a result research in geomorphology has been directed towards the understanding of fine sediment dynamics. It was identified by a review of published literature that at present a paucity of information on sediment dynamics existed for the East Midlands, UK. The use of tracers within a sediment fingerprinting framework has recently become a heavily used technique to investigate the sources of fine sediment pressures. However, uncertainties associated with tracer behaviour have been cited as major potential limitations to sediment fingerprinting methodologies. At present few studies have quantified the uncertainties associated with tracer use, or the exact reasons why different tracers are producing different sediment provenance results. This thesis had two aims based on these gaps in published literature. First, to assess the impact of sediment sampling methodology, tracer selection, particle size corrections and organic enrichment corrections on a fine sediment fingerprinting study. Secondly, to develop a partial sediment budget for the Upper Nene river basin and its major tributaries. The results of this thesis were presented in two parts. The first part investigated Aim 1 when fingerprinting; historically deposited sediment, suspended sediment and recently deposited sediment. The second part investigated Aim 2 by constructing a fine sediment budget for the Nene river basin, consisting of; sediment yield, sediment provenance, floodplain sediment accumulation and channel bed sediment storage. A mean difference of 24.1% between the predicted contributions of sediment originating from channel banks was found when using nine different tracer groups to fingerprint the river sediment samples. When fingerprinting contributions from urban street dusts mean differences between tracer group predictions were lower, at between 8% and 11%. There was little indication that organic matter content and / or particle size caused differences between tracer group predictions. Within-source variability in tracer concentrations, and small contrasts between the tracer concentrations of the sediment source groups, were identified as probable causes of inherent uncertainty present in the fingerprinting analysis. It was determined that the ratio of the percentage difference between median tracer concentrations in the source groups and the average within-source tracer concentration coefficient of variation could indicate the likely uncertainty in model predictions prior to tracer use. When fingerprinting historically deposited sediment, a reservoir core was fingerprinted with the least uncertainty, with tracer group provenance predictions ~28% apart and with consistent down-core trends. When fingerprinting an on-line lake core and four floodplain cores, differences between tracer group predictions were as large as 100%; the down-core trends in changing sediment provenance were also different. The differences between tracer group predictions could be attributed to the organic matter content and particle size of the sediment. There was also evidence of the in-growth of bacterially derived magnetite and chemical dissolution affecting the preservation of tracer signatures. Despite the prior indications that organic matter and particle size were causing tracer non-conservatism in historical sediment cores, data corrections were found to often be ineffective at reducing the differences between tracer group predictions. The corrections were found to either have no effect on, or increase the mean differences between, tracer group predictions when fingerprinting river sediment. The sediment budget identified that the annual sediment yield of 13 - 19 t km-2 yr-1 for the Nene is low in comparison to other UK catchments. Channel banks were found to be the dominant sediment source in the Nene, typically contributing between 60% and 100% of the sediment. Rates of sediment accumulation on the Nene’s floodplain was found to be highly variable (920– 7,200 t km-2 yr-1); the presence of flood defences were likely to be a cause of this variability, and have caused a reduction in the accumulation rate since 1963. It was found that large quantities of sediment accumulated on channel beds during periods of low flows (~ 28% of the annual sediment yield), which was flushed from the bed by a series of flood events (leaving <1% of the annual sediment yield in temporary storage). An original contribution to research was made by quantifying the uncertainties associated with tracer use in a fine sediment fingerprinting investigation, as well as identifying the probable causes of the observed uncertainty. The fine sediment dynamics of the Nene basin were also investigated for the first time, and it was identified that the high contributions from channel banks in the Nene were highly a-typical for UK catchments.

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Kneece, Molly Rebecca. "Breeding and brood rearing ecology of Mottled Ducks in the Ashepoo, Combahee, and Edisto Rivers Basin, South Carolina." Thesis, Mississippi State University, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10100314.

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Mottled ducks (Anas fulvigula) are a non-migratory waterfowl species endemic to the western Gulf Coast, with a separate, genetically distinct subspecies (A. fulvigula fulvigula) occurring in peninsular Florida. Birds from Texas, Louisiana, and Florida were released in coastal South Carolina from 1975-1983, and banding data suggest an expanding population. I monitored 72 mottled duck nests and captured and radio-marked 196 pre-breeding and nesting females between 2010 and 2014 to study breeding ecology of these birds in the Ashepoo, Combahee, Edisto Rivers Basin. Nest success averaged 12% and varied with vegetation height and year. Indicated breeding pair surveys revealed breeding mottled ducks select managed wetland impoundments, predominately influenced by water depth. Future research should investigate ecology of nest predators of mottled ducks to devise successful habitat management strategies for breeding birds. Preliminary evidence suggests that managed wetland impoundments are important to breeding and brood rearing mottled ducks in coastal South Carolina.

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Hill, Clement Michael. "The magnitude of sediment delivery within a rivers drainage basin on the tropical coast of north east Queensland." Thesis, Queensland University of Technology, 1993. https://eprints.qut.edu.au/37120/1/37120_Hill_1993.pdf.

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The 530 km2 South Johnstone River catchment was the focus of a detailed investigation into sediment erosion and depositional processes. The area is subject to some of the highest rainfall totals in Australia with very intense storms and tropical cyclones. The catchment is divided almost equally into three topographical regions, the eastern coastal plain, the lower erosion surface and the middle erosion surface. The latter comprise granite, metamorphic and basalt bedrock forming a deeply incised, mountainous region abutting the Atherton tableland. The coastal plain is up to 14 km wide and comprises rich cropping soils derived from alluvium and basalt. This study aimed to determine the sediment delivery from the catchment and erosional and depositional processes occurring within the catchment. Methods used in the is study included sediment sampling and grainsize analysis, sediment textural analysis, water sampling for suspended sediment, catchment scale computer modelling and GIS applications. Results obtained from this study include the determination of a catchment sediment delivery ratio of 52 % comprising greater than 80 % silt and clay sized sediment. Long term average catchment sediment yield is 165900 t a-1• Mean catchment erosion rate is 3 t ha-1 a-1• These findings are significantly higher than previous estimates of catchment sediment yield. The high content of fine grained sediment b.eing delivered from caneland catchments poses a significant offshore risk in terms of water quality and is a potential hazard to the Great Barrier Reef.

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Al-Hawas, Ibrahim A. M. "Clay mineralogy and soil classification of alluvial and upland soils associated with Blackwater and Nottoway rivers in southeastern Virginia." Thesis, Virginia Tech, 1989. http://hdl.handle.net/10919/44104.

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Because the Coastal Plain of southeastern Virginia has not been extensively studied, thirty random samples associated with Blackwater and Nottoway rivers were collected in the spring of 1987 from Surry, Sussex, and Southampton counties. Soil classification as well as mineralogical, chemical, and physical analysis were conducted for all samples.

The purposes of this investigation were to: (1)classify the soils in this area, (2) determine the distribution of sand and clay minerals, (3) examine the weathering effect on clay minerals on different position of the landscape for different parent material sources.

The soils examined classified as follow: Aquic Hapludults 43% > Typic Hapludults 26.6% > Ultic Hapludalfs 10% > Humic Hapludults 3% = Typic Rhodudlts 3% = Aquic Hapludalfs 3% = Typic Udipsamment 3% = Typic Quartzpsamment 3% = Psammentic Hapludalfs. Qualitative analysis of clay minerals revealed that kaolinite and hydroxy interlayer vermiculite were the dominant clay minerals; that montmorillonite, mica, gibbsite quartz, and vermiculite were of lesser quantities; that chlorite, feldspar and interstratified minerals were of trace amounts. Kaolinite represents about 21-70%, HlV 11-60%, montmorillonite 0-20%, mica 0-16%, gibbsite 0-13%, quartz 1-12%, and vermiculite 0-10%. The presence of these minerals were mainly related to the acid reaction of the soil media, which was essentially attributed to Al and H ions in soil solution. From the past history and geological composition of the Piedmont it is assumed that kaolinitic minerals were transported and sedimented in the Coastal Plain. Hydroxy-interlayer vermiculite minerals was weathering from vermiculite because most of the Al was adsorbed by vermiculite to form HIV. Therfore, gibbsite was not precipitated. Montmorillonite was assumed to have formed from mica minerals. That was substantiated by statistical analysis which showed a high negative correlation between gibbsite and vermiculite (r=0.46, n=30) and between montmorillonite and mica (r=-0.6, n=10).

Master of Science

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44

Tromboni, Flavia. "Integrated hydrologic-economic model for sustainable water resources management in front of climate change. The Tunuyán River basin and the Piave River Basin case studies." Doctoral thesis, Università degli studi di Padova, 2011. http://hdl.handle.net/11577/3423337.

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Abstract The research carried out investigated the structure of the complex system composed by hydrological, economic and climatic variables, with the aim of sustainable water management modelling. Two case studies (the Tunuyán River Basin and Piave River Basin) were investigated, applying different methodologies for data analysis, due to the diverse management objectives and specific site characteristics. In the Tunuyán River Basin case study a correlation analysis on time series data of annual grape yields, sugar rate, monthly temperatures and precipitations was carried on, in order to individuate possible relations between them. Strong correlations were found between annual grape yield and minimum temperature of June, minimum temperature of July, maximum temperature of January, maximum temperature of October and the PVC index of precipitations. Correlations were strong also between sugar rate in grape and minimum temperature of July, minimum temperature of November, Minimum temperature of December, Maximum temperature of February, Maximum temperature of November and the PVC index. A multi-linear regression analysis was then applied to data in order to quantify those relations. A Mann Kendall analysis was applied on time series of meteorological data and the Tunuyán River up flow discharge, to detect significant trends. Significant positive trends were identified on the total annual river flow and on mostly monthly river flows except for July, August, September and December monthly flows, which trends were not significant. The optimum area to be sustainable irrigated with a 12” pump, energy requirements and energy cost for water extraction were estimated using data available from pumping tests. Irrigation water demand as total crop water requirements was estimated using the FAO Penman-Monteith formula. Energy cost variations were examined to evaluate the economic impact of climate warming. The cultivated area increase rate (as a consequence of economic development) was also considered. Finally, all variables were integrated in a whole dynamic system model written in Vensim, to analyse the dynamic of the entire system through time. The objective formula of the integrated model is the maximisation of net benefit minimizing water use. In the Piave River Basin case study a Mann-Kendall trend analysis was carried on to detect trends in time series of monthly precipitations. Significant trends were indentified identified only in September precipitations. An optimization model written in GAMS was applied to estimate the cultivation pattern for optimum water allocation.
Abstract La ricerca ha analizzato la sruttura del sistema complesso costitutio da variabili idrologiche, economiche e climatiche, con l’obbiettivo della modellazioneper la gestione sostenibile delle risorce idriche. Due casi studi sono stati approfonditi, il bacino del fiume Tunuyan (Mendoza, Argentina) e il bacino del fiume Piave (Italia). Diverse metodologie di analisi dei dati sono state applicate, a causa di diversi obbiettivi gestionali e seconda della caratteristiche specifiche di ciascuna zona. Nel caso studio del bacino del fiume Tunuyan è stata condotta un’analisi di correlazione tra serie storiche di dati di produzione di uva, tenore zuccherino nell’uva, temperature mensili di precipitazioni, con l’obbiettivo di identificare possibili relazioni tra le variabili. Forti correlazioni sono state identificate tra produzione annuale di uva e temperatura minima di Giugno, temperatura minima di Luglio, temperatura minima di Novembre, temperatura minima di dicembre, temperatura massima di febbraio, temperatura massima di Novembre e l’indice PVC di precipitazioni. Un’analisi di regressione lineare multipla è infine stata applicata ai dati per quantificare tali relazioni. L’analisi delle tendenze delle serie storiche di dati meteorologici e di portata del fiume Tunuyán è stata condotta attraverso il test non parametrico Mann Kendall, che ha permesso di valutare le tendenze significative. Tendenze positive sono state identificate nella portata a monte totale e in quasi tutte le serie storiche delle portate mensili, tranne per Luglio, Agosto, Settembre e Dicembre, le cui tendenze sono risultate non significative. L’area di irrigazione ottimale con una pompa di estrazione di 12” ,le necessità energetiche e i costi di estrazione dell’acqua sotterranea sono stati calcolati attraverso i dati disponibili da test di pompaggio condotti dall’INA (Istituto Nacional del Agua di Mendoza). La domanda irrigua, calcolata come necessità idriche delle colture è stata stimata usando la formula FAO Penman-Monteith. Le variazioni nei costi sono state esaminate per valutare i possibili impatti del riscaldamento globale. L’incremento di area coltivata come conseguenza dello sviluppo economico è stato preso in considerazione. Infine tutte le variabili sono state integrate in un modello olisitco scritto in Vensim, con l’obbiettivo di analizzare la dinamica dell’intero sistema nel tempo. La formula obbiettivo del modello integrato è la massimizzazione dei profitti minimizzando l’utilizzo di risorsa idrica. Nel caso studio del bacino del Piave un’analisi di tendenza Mann-Kendall è stata condotta per individuare le tendenza nelle serie storiche di dati di precipitazione. Tendenze positive sono state identificate solo nelle precipitazioni di Settembre. Un modello di ottimizzazione scritto in GAMS è stato infine applicato per stimare il pattern di coltivazione per l’allocazione ottimale della risorsa idrica.

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45

Perry, Matthew T. "Design and evaluation of a web mapping service for the Klamath River Basin /." California : Humboldt State University, 2005. http://hdl.handle.net/2148/25.

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Dwyer, Brian James, University of Western Sydney, College of Social and Health Sciences, and School of Natural Sciences. "Aspects of governance and public participation in remediation of the Murray-Darling Basin." THESIS_CSHS_NS_Dwyer_B.xml, 2004. http://handle.uws.edu.au:8081/1959.7/776.

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This thesis addresses the question “What is the essence of the Murray Darling river system conundrum that is usually posed as an issue of environmental remediation?”- following perceptions of problems in catchment strategy formulation regarding project selection and public consultation. The question is initially seen as having four facets – governance, public, participation and remediation. An initial literature review indicated that previous examination of these topics seemed insufficiently radical or comprehensive for the enquiry’s purposes, seeming not to attribute full humanness to members of the public. A fieldwork program of quasi-anthropological nature was conducted. Interpretation of the fieldwork reports focuses primarily on the lack of attribution of full humanness to members of the public. Interpretive techniques including a phenomenological-style process was applied and found that the district houses a number of unrecognised people “nexors’ occupying linking or nexus roles who exercise personal skills and initiatives to underpin effective remediation outcomes. Towards the end of the fieldwork program, further literature indicated that the initial four-facet nature of the enquiry should be reformulated, to include the overall nature of western society as it appears in the district (in place of participation), to reconstitute the concept of remediation more radically. Governance as a topic is broader than the ways in which it appears in the examined district, and suitable hybridizing of competing world view concepts remains unresolved in this thesis
Doctor of Philosophy (PhD)

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47

Morris, Colleen, and ms_colleen_morris@hotmail com. "Water paths and the landscape: poetry of water paths watercourses waterways and rivers - fluid links between artists, ecology and the environment." RMIT University. Art, 2006. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20080702.144923.

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My project is a tribute to all water paths, waterways and rivers. It is an acknowledgement of their global significance, and of their mysterious and mythic presence in legend and history. The main body of the research and studio practice focuses on the Murray-Darling River System. Contained within the research there is a store of personal knowledge and memories of a complex river network. I view this research as my personal tribute. Some of the most important environmental challenges currently faced by us as a community in the twenty first century are water quality and water usage. By understanding and integrating people's needs, and ensuring that the communities in the Basin are able to engage in the process of change, a sense of identity can be fostered, so that long - term sustainability becomes a shared goal. Salinity, algal blooms, trading water property rights, and establishing a balance between the needs of the environment and the needs of the communities in the consumption of water are some of the strategies that are planned under the Murray - Darling Basin Initiative. For my exploration into the environment, ecology and poetry of water paths, I have researched and will discuss the work of a number of contemporary visual artists, and quoted from works of both writers and poets, to further illustrate aspects of a water path and landscape environment. My selection is primarily governed by artworks that specifically reference the human traces that mark or imprint on the landscape, water paths in the riverine landscape and the linked ecology. By reflecting on the broader position of water, its usage and control, it can be seen how this factor relates to the health of our ecological environment, and the most likely impact water usage and control will have in the future. Through both studio research and exegesis, I encapsulate a key part of childhood memory and significance of place, and established a sense of its importance within my integral identity. Simultaneo usly, the research explores the duality of this river environment and its atmospheric moods. I encompass the meditative qualities and beauty of this specific river environment, and include some investigation of social and ecological factors related to the presence and usage of water in the Murray - Darling Basin.

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48

Aulinas, Masó Montse. "Management of industrial wastewater discharges in river basins through agents'argumentation." Doctoral thesis, Universitat de Girona, 2009. http://hdl.handle.net/10803/7804.

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La gestió de l'aigua residual és una tasca complexa. Hi ha moltes substàncies contaminants conegudes però encara moltes per conèixer, i el seu efecte individual o col·lgectiu és difícil de predir. La identificació i avaluació dels impactes ambientals resultants de la interacció entre els sistemes naturals i socials és un assumpte multicriteri. Els gestors ambientals necessiten eines de suport pels seus diagnòstics per tal de solucionar problemes ambientals.
Les contribucions d'aquest treball de recerca són dobles: primer, proposar l'ús d'un enfoc basat en la modelització amb agents per tal de conceptualitzar i integrar tots els elements que estan directament o indirectament involucrats en la gestió de l'aigua residual. Segon, proposar un marc basat en l'argumentació amb l'objectiu de permetre als agents raonar efectivament. La tesi conté alguns exemples reals per tal de mostrar com un marc basat amb agents que argumenten pot suportar diferents interessos i diferents perspectives. Conseqüentment, pot ajudar a construir un diàleg més informat i efectiu i per tant descriure millor les interaccions entre els agents. En aquest document es descriu primer el context estudiat, escalant el problema global de la gestió de la conca fluvial a la gestiódel sistema urbà d'aigües residuals, concretament l'escenari dels abocaments industrials. A continuació, s'analitza el sistema mitjançant la descripció d'agents que interaccionen. Finalment, es descriuen alguns prototips capaços de raonar i deliberar, basats en la lògica no monòtona i en un llenguatge declaratiu (answer set programming).
És important remarcar que aquesta tesi enllaça dues disciplines: l'enginyeria ambiental (concretament l'àrea de la gestió de les aigües residuals) i les ciències de la computació (concretament l'àrea de la intel·ligència artificial), contribuint així a la multidisciplinarietat requerida per fer front al problema estudiat. L'enginyeria ambiental ens proporciona el coneixement del domini mentre que les ciències de la computació ens permeten estructurar i especificar aquest coneixement.
Wastewater management is a very complex task. There is a high number of known and an increasing number of unknown pollutants whose individual and collective effects are very difficult to predict. Identifying and evaluating the impacts of environmental problems resulting from the interactions between our social system and its natural environment is a multifaceted critical issue. Environmental managers require tools to support their diagnoses for solving these problems. The contributions of this research work are twofold: first, to propose the use of an agent-based modelling approach in order to conceptualize and integrate all elements that are directly or indirectly involved in wastewater management. Second, to propose a framework based on argumentation that allows to reason effectively. The thesis provide some real examples to show that an agent-based argumentation framework can deal with multiple interests and different agents' perspectives and goals. This help to build a more effective and informed dialog in order to better describe the interaction between agents. In this document we first describe the context under study, scaling down the global river basins system to the urban wastewater systems and giving some more details for the specific scenario of industrial wastewater discharges. Then, we analyze the system in describing intelligent agents that interact. Finally, we propose some reasoning and deliberation prototypes by using an argumentation framework founded on non-monotonic logics (i.e. permitting to learn things that were previously not known) and the answer set programming specification language (i.e. a declarative programming language). It is important to remark that this thesis links two disciplines: environmental engineering (specifically the area of wastewater management) and computer science (specifically the area of artificial intelligence), contributing to the required multidsciplinarity needed to confront the complexity of the problem under study. From environmental engineering we obtain the domain knowledge whereas the computer science field permits us to structure and specify this knowledge.

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49

Jones, Stuart Jason. "The evolution of alluvial systems in the south central Pyrenees, Spain." Thesis, University of Reading, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.301956.

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50

Kaewkrajang, Vuttichai. "Integrated planning of water quality management system in the Tha Chin River Basin." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0017/MQ54715.pdf.

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Dissertations / Theses on the topic 'Rivers- Rivers basin and systems'

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