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An analysis of unconfined ground water flow characteristics near a seepage-face boundarySimpson, Matthew January 2003 (has links)
A quantitative understanding of ground water flow characteristics in unconfined aquifers is important because of the prevalence of abstraction from, and pollution of these systems. The current understanding of ground water flow in unconfined aquifers is limited because of the dominance of horizontal flow modelling strategies used to represent unconfined flow processes. The application of horizontal flow principles leads to an ignorance of seepage-face formation and can not predict the complicated three-dimensional nature of the ground water flow that dominates at the ground water-surface water interface. This study aims to address some of these deficiencies by exploring the true three-dimensional nature of ground water flow including the formation of seepage faces at the ground water-surface water interface using numerical and laboratory techniques. A finite element model for simulating two-dimensional (vertical) variably saturated flow is developed and benchmarked against standard laboratory and field-scale solutions. The numerical features of the finite element model are explored and compared to a simple finite difference formulation. The comparison demonstrates how finite element formulations lead to a broader spatial averaging of material properties and a different method for the representation of specified flux boundaries. A detailed comparison analysis indicates that these differences in the finite element solution lead to an improved approximation to the partial differential equation governing two-dimensional (vertical) variably saturated flow. A laboratory analysis of unconfined ground water flow and associated solute transport characteristics was performed. The analysis focused upon unconfined flow towards a pumping well. The laboratory observations were reliably reproduced using a three-dimensional (axi-symmetric), variably saturated ground water flow model. The model was benchmarked against the ground water flow characteristics such as the seepage-face height and total flow rate. In addition, the model was shown to reliably reproduce the solute transport features such as travel times and streamline distributions. This is the first time that a numerical model has been used to reliably reproduce the solute transport characteristics near a seepage-face boundary where the three-dimensional flow effects are prevalent. The ability to reliably predict solute transport patterns in the seepage-face zone is important since this region is known to support vital microbially facilitated reactions that control nutrient cycling and contaminant attenuation. The three-dimensional travel time distribution near the seepage-face was compared to that predicted using a horizontal flow modelling approach derived from the basic Dupuit-Forchheimer equations. The Dupuit-Forchheimer based model indicated that horizontal flow modelling would under-estimate the total residence time near a seepage-face boundary, thereby introducing a considerable source of error in a solute transport analysis. For this analysis, a new analytical solution for the steady travel time distribution in an unconfined aquifer subject to a single pumping well was derived. The analytical model has identified, for the first time in the hydrogeology literature, the use of the imaginary error function. The imaginary error function is a standard transcendental function and an infinite series approach to evaluate the function was successfully proposed. The two-dimensional (vertical) ground water flow model was extended to handle the case where the flow is driven by density gradients near the ground water-surface water interface. The unsteady, two-dimensional, Galerkin finite element model of density-dependent ground water flow in variably saturated porous media is rigorously presented and partially benchmarked under fully saturated (confined) conditions. The partial benchmarking involved reproducing solutions to the standard Henry salt-water intrusion and the Elder salt-convection problems. The model was used in a standard density-coupled and a new density-uncoupled mode to elucidate the worthiness of the Henry and Elder problems as benchmark standards. A comparison of the coupled and uncoupled solutions indicates that the Henry salt-water intrusion problem has limited worthiness as a benchmark as the patterns of ground water flow are relatively insensitive to density-coupled effects. Alternatively, the Elder problem is completely dependent upon a correct representation of the density-coupled flow and solute transport processes. The coupled versus uncoupled comparison is proposed as a new test of the worthiness of benchmark standards. The Henry salt-water intrusion problem was further analysed in an attempt to alleviate some of the difficulties associated with this benchmark problem. The numerical model was tested against a re-evaluated version of Henry's semi-analytical solution for the coupled solute concentration distribution. The numerical model was used to propose a modified version of the Henry problem where the importance of density-coupled processes was increased. The modified problem was shown to have an improved worthiness as compared to the standard solution. The numerical model results were benchmarked against a new set of semi-analytical results for the modified problem. Certain advantages in using the modified problem as a test case for benchmarking the results of a numerical model of density-dependent ground water flow are identified. A numerical investigation of the patterns of density-driven ground water flow at the ground water-surface water interface was undertaken. The numerical model is shown to produce grid-independent results for a finely discretised domain. The pattern of discharge is controlled, in part, by two parameters. One describes the recharge applied to the aquifer, and the second describes the magnitude of the density differences between the fresh recharging fluid and the saline receiving fluid. The influence of dense intrusions upon the formation of seepage-face boundaries at the ground water-surface water interface under steady-state conditions was also investigated. Dense intrusions are shown to dominate the pattern of ground water flow only under mild recharge conditions, while seepage faces dominate the outflow pattern under strong recharge conditions. Therefore, the formation of seepage-face boundaries and dense intrusions are unlikely to coincide under the conditions examined in this study.
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Identifying misconnection hotspots using coliforms and biofilm communitiesChiejina, Chidinma January 2016 (has links)
Sewage misconnections currently pose severe threats to water quality especially in urban areas in the UK. These misconnections lead to the discharge of untreated wastewater into receiving watercourses via surface water outfalls. Regular discharges from this source could lead to these watercourses failing to meet standards set by the Water Framework Directives. Despite the impacts resulting from this urban diffuse pollutant source, research into this area is limited. The study area is the River Lee, which is known to experience issues with water quality especially within the heavily urbanized lower Lee section. Misconnections are one of the major contributors to the poor water quality status of the River. In this study, the Lee was investigated using several parameters. The approach involved the monitoring of coliform bacteria to detect outfalls where misconnections were likely, then biofilm samples below selected outfalls were used for both clean and polluted sites to look for community types. Results showed severe pollution within some sections of the River particularly within the lower Lee. Pymmes Brook was used as a case study, both coliform bacteria and biofilm communities below outfalls were further investigated for clean and polluted sites. Results from the Pymmes Brook study also showed that this watercourse was experiencing severe issues with water quality, with elevated levels of coliform bacteria identified below polluted outfalls. Biofilm community data obtained during the pilot and experimental phases of study were analyzed using a range of multivariate techniques. Results of the analysis showed consistent x patterns in community structure within sites with similar water quality, with indicator species identified. Communities below polluted outfalls were composed mainly of species tolerant of organic pollution thus indicating a response of communities to misconnection discharges. Currently, the identification of misconnections are carried out through trackbacks, a process which is expensive and time consuming. During this study an inexpensive and rapid approach is proposed for assessing misconnections within a catchment. Using this method, misconnection hotspots are mapped out using coliform bacteria and biofilm communities. Using catchment data and predicted coliform bacteria from enumerated counts, misconnections within these hotspots are assessed. Having tested this approach on Pymmes Brook, a tributary of the River Lee, the results obtained were promising. Pending further verification, this system provides an economical and rapid tool for the assessment of misconnections within a catchment.
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Understanding urban rainfall-runoff responses using physical and numerical modelling approachesGreen, Daniel January 2018 (has links)
This thesis provides a novel investigation into rainfall-runoff processes occurring within a unique two-tiered depth-driven overland flow physical modelling environment, as well as within a numerical model context where parameterisation and DEM/building resolution influences have been investigated using an innovative de-coupled methodology. Two approaches to simulating urban rainfall-runoff responses were used. Firstly, a novel, 9 m2 physical modelling environment consisting of a: (i) a low-cost rainfall simulator component able to simulate consistent, uniformly distributed rainfall events of varying duration and intensity, and; (ii) a modular plot surface layer was used. Secondly, a numerical hydroinundation model (FloodMap2D-HydroInundation) was used to simulate a short-duration, high intensity surface water flood event (28th June 2012, Loughborough University campus). The physical model showed sensitivities to a number of meteorological and terrestrial factors. Results demonstrated intuitive model sensitivity to increasing the intensity and duration of rainfall, resulting in higher peak discharges and larger outflow volumes at the model outflow unit, as well as increases in the water depth within the physical model plot surface. Increases in percentage permeability were also shown to alter outflow flood hydrograph shape, volume, magnitude and timing due to storages within the physical model plot. Thus, a reduction in the overall volume of water received at the outflow hydrograph and a decrease in the peak of the flood event was observed with an increase in permeability coverage. Increases in the density of buildings resulted in a more rapid receding limb of the hydrograph and a steeper rising limb, suggesting a more rapid hydrological response. This indicates that buildings can have a channelling influence on surface water flows as well as a blockage effect. The layout and distribution of permeable elements was also shown to affect the rainfall-runoff response recorded at the model outflow, with downstream concentrated permeability resulting in statistically different hydrograph outflow data, but the layout of buildings was not seen to result in significant changes to the outflow flood hydrographs; outflow hydrographs appeared to only be influenced by the actual quantity and density of buildings, rather than their spatial distribution and placement within the catchment. Parameterisation of hydraulic (roughness) and hydrological (drainage rate, infiltration and evapotranspiration) model variables, and the influence of mesh resolution of elevation and building elements on surface water inundation outputs, both at the global and local level, were studied. Further, the viability of crowdsourced approaches to provide external model validation data in conjunction with dGPS water depth data was assessed. Parameterisation demonstrated that drainage rate changes within the expected range of parameter values resulted in considerable losses from the numerical model domain at global and local scales. Further, the model was also shown to be moderately sensitive to hydraulic conductivity and roughness parameterisation at both scales of analysis. Conversely, the parameterisation of evapotranspiration demonstrated that the model was largely insensitive to any changes of evapotranspiration rates at the global and local scales. Detailed analyses at the hotspot level were critical to calibrate and validate the numerical model, as well as allowing small-scale variations to be understood using at-a-point hydrograph assessments. A localised analysis was shown to be especially important to identify the effects of resolution changes in the DEM and buildings which were shown to be spatially dependent on the density, presence, size and geometry of buildings within the study site. The resolution of the topographic elements of a DEM were also shown to be crucial in altering the flood characteristics at the global and localised hotspot levels. A novel de-coupled investigation of the elevation and building components of the DEM in a strategic matrix of scenarios was used to understand the independent influence of building and topographic mesh resolution effects on surface water flood outputs. Notably, the inclusion of buildings on a DEM surface was shown to have a considerable influence on the distribution of flood waters through time (regardless of resolution), with the exclusion of buildings from the DEM grid being shown to produce less accurate results than altering the overall resolution of the horizontal DEM grid cells. This suggests that future surface water flood studies should focus on the inclusion and representation of buildings and structural features present on the DEM surface as these have a crucial role in modifying rainfall-runoff responses. Focus on building representation was shown to be more vital than concentrating on advances in the horizontal resolution of the grid cells which make up a DEM, as a DEM resolution of 2 m was shown to be sufficiently detailed to conduct the urban surface water flood modelling undertaken, supporting previous inundation research.
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Avalia??o da qualidade geoqu?mica ambiental da ?gua superficial do Rio Jequitinhonha sob impacto de atividade garimpeiraFreitas, Mariana de Oliveira 14 August 2017 (has links)
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Previous issue date: 2017 / Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM) / Funda??o de Amparo ? Pesquisa do estado de Minas Gerais (FAPEMIG) / O garimpo denominado Areinha est? inserido na bacia hidrogr?fica do Rio Jequitinhonha,
bacia que se estende desde a por??o nordeste do Estado de Minas Gerais at? o sul do Estado
da Bahia (foz), cujas ?guas drenam ?reas urbanas, latif?ndios, minif?ndios e ?reas de
garimpos que afetam diretamente as caracter?sticas ambientais do recurso h?drico. A
modifica??o das atividades de garimpo, anteriormente manuais e atualmente
predominantemente mecanizadas, intensificou os impactos ambientais negativos nessa regi?o,
em consequ?ncia da necessidade de remo??o de grandes quantidades de sedimentos do fundo
do rio para a extra??o do diamante. Tendo em vista as particularidades naturais e as
caracter?sticas antr?picas, esta pesquisa tem como objetivo geral avaliar a situa??o ambiental
em que se encontra esse segmento da bacia. Dentre os objetivos espec?ficos, analisar
par?metros f?sico-qu?micos de qualidade da ?gua, como temperatura, pH, turbidez,
condutividade el?trica, oxig?nio dissolvido, cor aparente, s?lidos totais dissolvidos e
composi??o qu?mica para os seguintes elementos: Cu, Cd, Ni, Pb, Zn, Fe e Mn. Tem tamb?m
como objetivo espec?fico analisar a concentra??o, distribui??o e a prov?vel origem desses
metais nas ?guas superficiais, visando associar o poss?vel risco ambiental para a sa?de
humana da popula??o. O segmento do rio delimitado para estudo possui extens?o de
aproximadamente 9 km, referenciado pelas coordenadas geogr?ficas -17?54'21''48 S e -
43?30'01''57 W. As an?lises realizadas neste trabalho estabeleceram que as concentra??es dos
elementos Cu, Fe, Mn e Zn encontradas est?o muito acima do permitido pelo CONAMA
357/05, o que pode apresentar um risco direto ? sa?de dos garimpeiros, e indireto para a
popula??o localizada ? jusante do rio, bem como para o equil?brio dos recursos naturais. Os
valores dos par?metros f?sico-qu?micos cor, turbidez, condutividade el?trica e oxig?nio
dissolvido est?o bem acima do preconizado pelo CONAMA 357/05, e pode ocasionar
preju?zos para os organismos aqu?ticos e para flora local, e na maior disponibilidade dos
elementos qu?micos identificados. Dentre as amostras coletadas, os pontos que apresentaram
os maiores valores dos elementos qu?micos e par?metros f?sico-qu?micos foram aqueles que
estavam localizados nas bacias de reten??o. Estes dados indicam que os rejeitos provenientes
do processo de garimpagem contribuem significativamente para a contamina??o da ?rea.
Estes resultados alertam para o comprometimento da qualidade da ?gua do Rio Jequitinhonha,
indicando que a atividade garimpeira na ?rea de estudo exerce um risco potencial para o
equil?brio dos sistemas naturais, bem como para a sa?de dos seres humanos. Dessa forma,
recomenda-se que os recursos h?dricos, as ?reas no entorno do garimpo e as condi??es de uso
da bacia de rejeitos sejam monitoradas periodicamente pelos ?rg?os oficiais, e que seja ainda
realizado um plano de recupera??o de ?reas degradadas, uma vez que, a retirada da vegeta??o
para abertura de catas e o revolvimento do solo comprometeram toda a din?mica ambiental. / Disserta??o (Mestrado Profissional) ? Programa de P?s-Gradua??o em Sa?de, Sociedade e Ambiente, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2017. / The mining project called Areinha is part of the Jequitinhonha River basin, which extends
from the northeastern portion of the State of Minas Gerais to the south of the State of Bahia
(river mouth), whose waters drain urban areas, latifundia, minifundios and mining areas,
which directly affect the environmental characteristics of the water resource. The
modification of mining activities, previously manual and currently predominantly
mechanized, intensified the negative environmental impacts in this region, as a result of the
need to remove large amounts of sediment from the river bottom for the extraction of
diamond. Taking into account the natural peculiarities and the anthropic characteristics, this
research has as general objective to evaluate the environmental situation in which this
segment of the basin is located. Among the specific objectives, to analyze physical and
chemical parameters of water quality, such as temperature, pH, turbidity, electrical
conductivity, dissolved oxygen, apparent color, total dissolved solids and chemical
composition for the following elements: Cd, Cu, Fe, Mn, Ni, Pb and Zn. It also has as a
specific objective to analyze the concentration, distribution and probable origin of these
metals in surface waters, aiming to associate the possible environmental risk to the human
health of the population. The segment of the river delimited for study has an extension of
approximately 9 km, referenced by the geographical coordinates -17?54'21''48 S E; -
43?30'01''57 W. The analyzes carried out in this work established that the concentrations of
Cu, Fe, Mn and Zn elements found are much higher than allowed by CONAMA 357/05,
which may present a direct risk to the health of the garimpeiros, and indirect to the population
located downstream of the river, as well as for the balance of natural resources. The values of
the physical-chemical parameters color, turbidity, electrical conductivity and dissolved
oxygen are well above that recommended by CONAMA 357/05, and can cause damages to
aquatic organisms and to local flora, and to the greater availability of the identified chemical
elements. Among the collected samples, the points that presented the highest values of the
chemical elements and physical-chemical parameters were those that were located in the
retention basins. These data represent that the wastes from the mining process contribute
significantly to the contamination of the area. These results point to the impairment of water
quality of the Jequitinhonha River, indicating that the garimpeira activity in the study area
poses a potential risk to the balance of natural systems, as well as to human health. Therefore,
it is recommended that the water resources, the areas around the garimpo and the conditions
of use of the tailings basin be monitored periodically by the official agencies, and that a
recovery plan for degraded areas is also carried out, since, the withdrawal of vegetation to the
opening of tastings and the revolving of the soil compromised the whole environmental
dynamics. / Se ha insertado el garimpo denominado Areinha en la cuenca hidrogr?fica del R?o
Jequitinhonha, cuenca que se extiende desde la porci?n noreste del Estado de Minas Gerais
hasta el sur del Estado de Bah?a (foz), cuyas aguas drenan ?reas urbanas, latifundios,
minifundios y ?reas de garimpos que afectan directamente las caracter?sticas ambientales del
recurso h?drico. La modificaci?n en las actividades de garimpo, anteriormente manuales y
actualmente predominantemente mecanizadas, intensific? los impactos ambientales negativos
en esa regi?n, consecuencia de la necesidad de remoci?n de grandes cantidades de sedimentos
del fondo del r?o para la extracci?n del diamante. En vista de las particularidades naturales y
las caracter?sticas antr?picas, esta investigaci?n tiene como objetivo general evaluar la
situaci?n ambiental en que se encuentra ese segmento de la cuenca. En los objetivos
espec?ficos, analizar par?metros f?sico-qu?micos de calidad del agua, como temperatura, pH,
turbidez, conductividad el?ctrica, ox?geno disuelto, color aparente, s?lidos totales disueltos y
composici?n qu?mica para los siguientes elementos: Cu, Cd, Fe, Mn, Ni, Pb y Zn. Tambi?n
tiene como objetivo espec?fico analizar la concentraci?n, distribuci?n y el probable origen de
estos metales en las aguas superficiales, con el fin de asociar el posible riesgo ambiental para
la salud humana de la poblaci?n. El segmento del r?o delimitado para estudio tiene una
extensi?n de aproximadamente 9 km, referenciado por las coordenadas geogr?ficas -
17?54'21''48 S e -43?30'01''57 W. Los an?lisis realizados en este trabajo establecieron que las
concentraciones de los elementos Cu, Fe, Mn y Zn encontradas est?n muy por encima de lo
permitido por el CONAMA 357/05, lo que puede presentar un riesgo directo a la salud de los
garimpeiros, e indirecto para la poblaci?n localizada aguas abajo del r?o, as? como para el
equilibrio de los recursos naturales. Los valores de los par?metros f?sico-qu?micos color,
turbidez, conductividad el?ctrica y ox?geno disuelto est?n muy por encima del preconizado
por el CONAMA 357/05, y puede ocasionar perjuicios para los organismos acu?ticos y flora
local, y en la mayor disponibilidad de los elementos qu?micos identificados. Entre las
muestras recogidas, los puntos que presentaron los mayores valores de los elementos
qu?micos y par?metros f?sico-qu?micos fueron aquellos que estaban ubicados en las cuencas
de retenci?n. Estos datos indican que los desechos provenientes del proceso de goteo
contribuyen significativamente a la contaminaci?n del ?rea. Estos resultados alertan sobre el
compromiso de la calidad del agua del R?o Jequitinhonha, indicando que la actividad minera
en el ?rea de estudio ejerce un riesgo potencial para el equilibrio de los sistemas naturales, as?
como para la salud de los seres humanos. De esta forma, se recomienda que los recursos
h?dricos, las ?reas en el entorno del garimpo y las condiciones de uso de la cuenca de
rechazos, sean monitoreadas peri?dicamente por los ?rganos los oficiales, y que se siga
realizando un plan de recuperaci?n de ?reas degradadas, una vez que, la retirada de la
vegetaci?n para la apertura de catas y el revolvimiento del suelo comprometieron toda la
din?mica ambiental.
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Assoreamento em densas redes de reservatórios: o caso da bacia hidrográfica da barragem Pereira de Miranda, Ce. / Sedimentation in dense networks of reservoirs in water availability in the region: the case of the dam basin Pereira de Miranda, CELira, Daniely Lidiany Costa January 2012 (has links)
LIRA, Daniely Lidiany Costa. Assoreamento em densas redes de reservatórios: o caso da bacia hidrográfica da barragem Pereira de Miranda, Ce. 2012. 86 f. Dissertação (mestrado) - Universidade Federal do Ceará, Departamento de Engenharia Agricola, Programa de Pós-Graduação em Engenharia Agrícola, Fortaleza-CE, 2012. / Submitted by demia Maia (demiamlm@gmail.com) on 2016-06-20T16:12:24Z
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Previous issue date: 2012 / The present study aims at analyzing the impacts of the dense reservoir network of the Pereira de Miranda catchment in its sediment yield and water storage capacity of the system. The studied area is located in the Brazilian Semiarid region, in the State of Ceará, with an area of approximately 3230 km2. It has an average annual rainfall of 854 mm and an annual potential evaporation of 1464 mm. The predominant soil and vegetation type are luvissolo and open shrub caatinga. Satellite imageries from wet years were used to identify the reservoirs of the catchment. Erosion units were identified derived from map overlay of the parameters of the Universal Soil Loss Equation (USLE), which enables the estimation of sediment yield and the identification of areas with high sediment production. A simplified model was used to simulate the sediment routing through the dense reservoir network of the basin. For the estimation of sedimentation at the Pereira de Miranda Reservoir, different scenarios of the system structure were considered. A mean erosion rate of 59 t.ha-1.year-1 was estimated for the basin, in which 42% of the basin area presents a moderate degree of erosion. According to the model, silting of the Pereira de Miranda reservoir may vary from 1.1 to 2.6 %.decade-1, depending on the scenario considered. One may observe that upstream reservoirs are able to retain until 58% of the sediments that would reach the Pereira de Miranda reservoir. The very small reservoirs, with storage capacity below 100,000 m³, are able to retain almost 8% of the generated sediments, although they represent just 1.83% of the system water storage capacity. Sensitivity analysis shows that the sediment retention capacity of the upstream reservoirs may vary from 20 to 58%, depending on the system structure concerning the presence of upstream reservoirs from different size classes. One may still conclude that the reduction rate of water storage capacity at the system as a function of reservoir siltation is relatively larger then that observed for the Pereira de Miranda reservoir, due to the upstream sediment retention. / O presente estudo tem como objetivo analisar os impactos da densa rede de reservatórios da bacia hidrográfica do açude Pereira de Miranda (Pentecoste) na produção de sedimentos e capacidade de armazenamento hídrica do sistema. A bacia estudada localiza-se no Nordeste Brasileiro, no Estado do Ceará, com uma área de aproximadamente 3.230 km2. Possui uma precipitação média anual de 854 mm e evaporação potencial média observada em tanque do tipo classe A é de 1.464 mm. O solo e a vegetação predominante são do tipo luvissolo e caatinga arbustiva aberta. Imagens de satélite de anos úmidos foram utilizadas para levantamento da açudagem na bacia. Foram identificadas unidades de erosão derivadas da sobreposição de mapas dos parâmetros da Equação Universal de Perdas do Solo (EUPS), o que permitiu a estimativa da erosão localizada na bacia e identificação de áreas potencialmente produtoras de sedimento. Um modelo simplificado foi utilizado para simular a propagação de sedimentos pela densa rede de reservatórios da bacia. Para estimativa do assoreamento no reservatório Pereira de Miranda, diferentes cenários de estrutura do sistema foram considerados. Foi estimada uma taxa de erosão média na bacia de 59 t.ha-1.ano-1, sendo que 42% da área da bacia apresenta grau de erosão moderado. De acordo com o modelo, o assoreamento do reservatório Pentecoste pode variar de 1,1 a 2,6% por década, dependendo do cenário considerado. Observa-se ainda que os reservatórios de montante podem reter até 58% do sedimento que chegaria ao açude Pereira de Miranda. Os reservatórios muito pequenos, com capacidade de até 100.000 m³, embora representem apenas 1,83% da disponibilidade hídrica do sistema, são capazes de reter quase 8% do total de sedimento produzido. Análises de sensibilidade mostram que a capacidade de retenção de sedimentos nos reservatórios de montante pode variar de 20 a 58%, dependendo da estrutura do sistema quanto à existência de reservatórios de diferentes classes de tamanho. Constata-se ainda que a taxa de redução da capacidade de armazenamento hídrica do sistema em função do assoreamento dos reservatórios de montante é relativamente maior do que a observada para o açude Pereira de Miranda, devido à retenção de sedimentos a montante.
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Zpracování studie revitalizace malého zemědělsko-lesního povodí / Revitalization study for small agricultural-forest catchmentČASTA, Jiří January 2014 (has links)
Revitalization generally are activities leading to the recovery of ecosystems in the landscape and their stabilization. In this thesis are proposed changes for revitalization of small agro-forestry basin stream called Branná significantly disrupted trough conditions, the banks and a river basin, including throughput migration of aquatic animals.
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Vliv zemědělské činnosti na vybrané fyzikálně chemické parametry povrchových vod / The influence of agricultural activities on selected physical and chemical parameters of surface waterMIKEŠOVÁ, Aneta January 2018 (has links)
The aim of this diploma thesis was a statistical evaluation of the impact of farming methods and the land cover on hydrochemical parameters of surface waters drainage patterns in Novohradské mountains and identify the possible impact of agriculture on the valuesof these parameters. The area for the evaluation is consist of lower and upper parts of the basin of Pasecký, Bedřichovský and Váčkový stream. Sampling sites include agriculturally cultivated land, but also forest ecosystems. The work is mainly focused on the following parameters: conductivity, nitrate nitrogen (N-NO3-), suspended solids (NL105) and phosphate phosphorus (P-PO43-), which are parameters causing eutrophication of water. The parameters changes were analysed for the years 2014 - 2017. Significant differences were observed in the all three streams in the water chemisms between upper and lower parts of the watersheds of conductivity and nitrate nitrogen (N-NO3-). The results confirmed that the farming has a significant influence on the water quality in the Pasecký, Bedřichovský and Váčkový stream although it is an extensive farming.
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Análise da qualidade da água no Rio Catu da Bacia Hidrográfica do Rio Pojuca - BahiaRibeiro, Emerson Santos 13 December 2011 (has links)
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Previous issue date: 2011-12-13 / No Brasil, ações antrópicas como o lançamento de esgotos, desmatamento de mata ciliar e uso inadequado de defensivos agrícolas, têm causado danos à qualidade ambiental e da água dos rios, sobretudo quando estes rios cortam os grandes centros urbanos. Destaca-se entre as atividades que impactam negativamente estes corpos d’água o lançamento in natura de esgotos domésticos e efluentes industriais. Devido a que quando estes não são tratados, além de degradar a qualidade da água do rio, têm um grande impacto sobre as atividades das comunidades ribeirinhas. O objetivo geral da pesquisa foi analisar e diagnosticar o estado de poluição do Rio Catu no Estado da Bahia e propor medidas para melhorias na qualidade de sua água. A pesquisa constou de um questionário que levantou o uso das comunidades ribeirinhas do Rio Catu, levantamento dos pontos de lançamentos de esgotos industriais e residenciais, através da utilização de GPS e a análise da qualidade da água em 4 pontos do rio em dois períodos em maio e outubro de 2010 . As análises foram realizadas nos laboratórios do SENAI e do Laboratório de Estudos em Meio Ambiente - LEMA da UCSAL, assim como dos cálculos obtidos por meio do Índice de Qualidade de Água (IQA) que são uma forma simples de indicar a qualidade de sistemas hídricos. Neste trabalho é proposta a implementação da ponderação proveniente dos IQAs na metodologia de avaliação de qualidade de águas. Conclui-se que os lançamentos de esgotos e efluentes industriais causam impactos negativos à qualidade da água do Rio Catu, tendo consequências sobre a fauna e a flora do Rio e as comunidades ribeirinhas que precisam do rio para alguma atividade. / In Brazil, human activities such as dumping of sewage, deforestation of riparian vegetation and inappropriate use of pesticides, have caused damage to the environment and water quality of rivers, especially when these rivers cut the large urban centers. The launch of fresh domestic sewage and industrial effluents are among the activities that negatively impact these water bodies. When they are not treated it degrades the quality of river water, and this have a great impact on the activities of coastal communities. The aim of the research was to analyze and diagnose the state of pollution of the River Catu in Bahia and propose measures to improve the quality of the water. The survey consisted of a questionnaire that raised the use of the riverside communities of Rio Catu, a survey that pointed sewage spills from industrial and residential projects, through the use of GPS, and analysis of water quality in four sections of the river in two periods, in May and in October 2010. Analyses were performed in the laboratories of SENAI and Laboratory Studies in Environment - LEMA of UCSAL, as well as of the results obtained through the Water Quality Index (IQA) that are a simple way to indicate the quality of water systems. This paper proposes the implementation of the weighting of IQAS as a methodology to assess water quality. It is concluded that the release of sewage and industrial effluents cause negative impacts to water quality of Rio Catu, having an impact on the flora and fauna of the river and coastal communities that need the river for some activity.
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Caracterização gênica de linhagens de Escherichia coli isoladas da água do Rio Cuiabá, Mato GrossoGolin, Rossean 23 November 2015 (has links)
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Previous issue date: 2015-11-23 / O crescimento populacional associado ao processo de urbanização não planejado têm impactado os corpos hídricos com cargas poluidoras que podem incorporar uma enorme quantidade de agentes transmissores de doenças. Na bacia hidrográfica do Alto Paraguai encontra-se o Rio Cuiabá, que é um dos seus mais importantes formadores, e está em situação de deterioração na qualidade da água, com múltiplas implicações sociais, ambientais, econômicas e, sobretudo, na saúde pública. A Escherichia coli é um indicador de contaminação fecal nos corpos d’água advindo dos efluentes e esse trabalho objetivou identificar a diversidade gênica da E. coli na água do Rio Cuiabá entre os municípios de Cuiabá e Várzea Grande no Estado de Mato Grosso. Ocorreram três coletas no período de estiagem e três coletas no período de chuvas. Amostras de água foram coletadas em seção transversal do rio, na margem esquerda (1/6 – Ponto P1), no canal principal (1/2 – Ponto P2) e na margem direita (5/6 – Ponto P3). 299 culturas de E. coli foram isoladas do cultivo positivo em substrato cromogênico e fluorogênico (Colilert®), cultivadas em caldo nutriente e congeladas à temperatura de -20°C. Posteriormente 84,6% das cepas foram ativadas em TSB para extração e amplificação do DNA utilizando a técnica PCR. Os dados foram analisados pelo método de ligação média não ponderada de agrupamento aos pares e as distâncias genéticas foram obtidas pelo complemento aritmético do coeficiente de similaridade de Jaccard. O número de E. coli nas amostras de água coletadas durante a estação seca foi menor do que a densidade encontrada durante a estação chuvosa. A maior densidade pode ser atribuída em parte, ao escoamento superficial gerado a partir de eventos de chuva que transportam um elevado número de bactérias de vários pontos e fontes difusas para o leito do rio. Os produtos de amplificação da PCR das E. coli isoladas das amostras de água da margem esquerda (P1) do Rio Cuiabá apresentaram 97,22% de cepas similares apresentando menor diversidade gênica com 30,61% quando comparados os três pontos de coleta. Possivelmente a contaminação dessa margem esteja relacionada com efluentes domésticos corroborando com a elevada similaridade bacteriana. Os produtos de amplificação da PCR para os isolados de E. coli da margem direita (P3) geraram 98,21% de cepas similares e, entre os três pontos amostrais, esta margem apresentou maior diversidade gênica (36,73%). Esta maior diversidade pode estar relacionada com afluentes receptores de contaminantes, além de atividades agrícolas, criação de gado e suínos, existentes à montante do ponto de coleta no Rio Cuiabá. O canal principal do Rio Cuiabá no Ponto Amostral P2 apresentou um valor mediano de diversidade gênica (32,65%) em relação às margens. Mesmo com uma alta similaridade gênica (97,23%) entre as 253 cepas bacterianas do Rio Cuiabá ativadas houve uma variedade de cepas dissimilares, sugerindo serem possíveis E. coli com genes de virulência ou mesmo E. coli patogênicas. Estabelecendo assim, um aumento potencial na ameaça de risco para a saúde das populações se as eficiências de tratamento e controle de lançamento de efluentes domésticos, industriais e até mesmo poluições difusas, não possuírem uma adequada e contínua gestão. / Population growth and unplanned urbanization process have impacted water bodies with pollutant loads which can incorporate an enormous amount of disease agents. In the Upper Paraguay River Basin is the Cuiabá River, which is one of its most important affluent and is in deteriorating situation in water quality, with social, environmental, and economic implications, especially on public health. Escherichia coli is an indicator of faecal contamination in water bodies and this work aimed to identify the genetic diversity of E. coli in the water of Cuiabá River between the cities of Cuiabá and Várzea Grande in the State of Mato Grosso. Three sampling were performed in dry season and three sampling during the rainy season. Water samples were collected left bank (1/6 - point P1), main channel (1/2 - point P2) and right bank (5/6 - point P3) of the total width of the river. 299 E. coli strains were isolated by positive chromogenic and fluorogenic culture substrate (Colilert®), grown in nutrient broth and frozen at -20 ° C. Later, 84.6% of the strains were activated in TSB for DNA extraction and amplification using the PCR technique. Data were analyzed by average connection method unweighted grouping in pairs and genetic distances were calculated using arithmetic complement of the Jaccard similarity coefficient. The number of E. coli in water samples collected during the dry season was lower than the density found during the rainy season. The greater density can be attributed in part to runoff due rain events which carry a high number of bacteria to from several sources to the river. The amplification products of PCR of E. coli isolated from water samples on the left bank (P1) of the Cuiabá River showed 97.22% of similar strains having less genetic diversity with 30.61% when comparing the three sampling points. Possibly contamination of this margin is related to domestic effluents corroborating the high bacterial similarity. The PCR amplification products for E. coli isolates from the right bank (P3) generated 98.21% of similar strains and, among the three sampling points, this margin showed higher genetic diversity (36.73%). This greater diversity may be related to affluent receivers of contaminants, as well as agricultural activities, pigs and cattle breeding and pigs, existing upstream of the sampling point in Rio Cuiabá. The main channel of the Cuiaba River in the sampling point P2 had a median value of genetic diversity (32.65%) compared to banks. Even with a high genetic similarity (97.23%) among the 253 bacterial strains activated from the Cuiabá River there was a variety of dissimilar strains, suggesting are possible E. coli virulence genes or even pathogenic E. coli. Thus establishing a potential increase in the risk to the health of population if the efficiencies treatment and launch control domestic sewage, industrial and even diffuse pollution, do not have adequate and ongoing management.
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Osmose inversa aplicada no reúso da água do rio Sarapuí em processos industriais / Reverse osmosis applied in Sarapuí river water reuse in industrial processesRaphael da Rocha Sixel 14 December 2009 (has links)
O objetivo deste estudo foi analisar o desempenho de um sistema de captação e tratamento de água do rio Sarapuí, por meio de uma estação de tratamento composta por um sistema de pré-tratamento convencional, ligado a um sistema de separação por membranas de osmose inversa, no Município de Belford Roxo RJ, instalado para fornecer água de processo a instalações industriais. Foi verificado que a água captada encontra-se em condição bastante degradada e que a unidade de tratamento removeu, em média, 97% do teor dos poluentes presentes na água, enquadrando-a nos parâmetros requeridos pelo processo industrial. Foi possível comprovar que o processo de separação por osmose inversa pode ser utilizado em escala industrial, proporcionando ganhos econômicos consideráveis, além de evitar o consumo de água potável para fins de processos industriais e, ainda, contribuir para a retirada de carga orgânica de uma fonte degradada / The objective of this study was to analyze the performance of a system to capture and treat water from Sarapuí river through a treatment system consisting of a conventional pré-treatment stage, linked to a reverse osmosis separation system membranes, in the city of Belford Roxo - RJ, installed to provide process water for industrial plants. It was found that the water is captured in highly degraded condition and the treatment plant removed an average of 97% of the pollutants in the water, fitting the parameters required by the industrial process. It could be demonstrated that the separation process by reverse osmosis can be used on an industrial scale, providing significant economic gains, and avoid the consumption of potable water for industrial processes and also contribute to the removal of organic pollutants from a degraded source
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