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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Magnitude and controls of microbial nitrate production in the streams and till of a glaciated alpine catchment, Canadian Rocky Mountains, Alberta

Doxsey-Whitfield, Erin 26 April 2012 (has links)
In the summer of 2010, fieldwork was conducted in the Robertson Valley, Canadian Rocky Mountains, Alberta to assess the magnitude and controls of microbial nitrification in proglacial till and in supraglacial, subglacial, and proglacial streams. Seasonal precipitation and glacial and proglacial runoff was sampled for hydrochemical and stable isotope analyses (δ18O and δ15N of nitrate [NO3-]). Lower Ca:Mg ratios, higher mean Σmajor ions, and an increased importance of reactions with slower dissolution kinetics in subglacial streams and proglacial seeps indicated waters here experienced longer rock-water contact time than in dilute supraglacial streams. Additionally, waters emanating from longer residence time flowpaths acquired substantial NO3- from nitrification reactions. Using δ18O-NO3- in a simple end-member mixing model, the fraction of NO3- derived from microbial nitrification was estimated to be 44 to 56% in the two subglacial streams, and greater than 80% in proglacial seeps. These results show that atmospherically-derived nitrogen (N) in this glacial valley undergoes substantial biological cycling prior to export in surface runoff. Water flowing from the east subglacial stream (RE) received a larger portion of its melt from a sediment-rich, slow drainage system and had a higher proportion of nitrified NO3- compared to the west subglacial stream (RW), where runoff was similar in composition to supraglacial runoff, indicating that the nature of subglacial flowpaths is an important factor in determining the amount of microbially-cycled nutrients that are exported from a glacier. Sixteen 34-day in situ soil incubations revealed that net mineralization and net nitrification occurred at all four sampling sites in the glacier forefield along a 1.6 km chronosequence; however, there was no significant difference among these rates with time since deglaciation or temperature. Instead, net mineralization and net nitrification rates were significantly correlated (p < 0.05, n = 16) with measured physical and chemical soil variables, including total organic carbon, total N, bulk density, pH, and clay content, suggesting that substrate availability is a larger control on N-cycling processes than time since deglaciation. High variability in inorganic soil N pools and N-cycling rates indicates that there are likely hot spots of biogeochemical activity within glacial till. / Thesis (Master, Geography) -- Queen's University, 2012-04-26 14:47:17.29
42

Spatial and temporal variation in the hydrochemistry of marine prawn aquaculture ponds built in acid sulfate soils, Queensland, Australia.

Groves, Sarah Anne, Biological, Earth & Environmental Sciences, Faculty of Science, UNSW January 2008 (has links)
Many brackish water aquaculture ventures in Australia and overseas have established ponds in coastal regions with acid sulfate soils (ASS). Acid sulphate soils are known to leach relatively high concentrations of metals, acid (metal and H+ ion) and sulfur, however very little is known about how these leached elements affect the water quality of aquaculture ponds. The main objective of this thesis was to describe the hydrochemical processes controlling the water chemistry in the water column and sediment pore water in the studied aquaculture ponds over time and space. Water samples providing the spatio-temporal data were collected from the ponds with the use of adapted sampling methods commonly used in the groundwater environment. A transect of five nested piesometers was installed in two prawn ponds at Pimpama, south east Queensland, Australia. Each piesometer nest contained a multilevel with eight outtakes, a mini ?? horizontal, and a slotted piesometer. Water samples were collected from each nested piesometer on a bi-monthly basis over the prawn-growing season. The unstable elements and water quality variables (pH, Eh, DO, EC, water temperature) were measured in the field. Stable elements were analysed in the laboratory using ICP-OES and ICP-MS. Soil samples were collected at the end of the season for elemental analysis. A number of key sediment/water interactions and processes such as precipitation/dissolution reactions, oxidation-reduction reactions, photosynthesis, adsorption and seawater buffering were identified as important controls on pond water conditions. This is the first study to provide detailed hydrochemcial analysis of the pond water over time and space and aided in identifying that even shallow water bodies can be chemically heterogeneous. Analysis of the water and sediment highlighted the selection of metals that can be associated with ASS and that are mobilised from pond sediments under certain chemical conditions. In Pond 7 Al, As, Ni and Zn concentrations were generally higher at the beginning of the grow-out season. Variability of the metal concentration was observed between the water column (0 ?? 1500 mm) and the pore-water (0 - -1000 mm). The highest concentration of Al (1044 ??g/L) and Zn (104 ??g/L) were sampled in the water column (approximately 400 mm from the surface of the pond). The highest concentration of As (130 ??g/L) and Ni (73 ??g/L) were sampled in the pore water sediment (associated with ASS). Elevated Mn and Fe2+ concentrations were also associated with the sediment pore water. The highest concentrations of Mn and Fe2+ were 4717 ??g/L and 5100 ??g/L respectively. In Pond 10, Ni concentrations (167 ??g/L) were the highest at the beginning of the grow-out season. However, As (97 ??g/L), Al (234 ??g/L) and Zn (308 ??g/L) were most concentrated during the middle of the cycle. The highest mean concentrations of these elements are As (63 ??g/L), Al (91 ??g/L) and Zn (69 ??g/L) which are each associated with the sediment-water interface. These metals are integral in degrading the pond water quality and lead to a loss of beneficial algal blooms, a reduction in pond water pH, poor growth rates and high mortality in shrimp. It is also possible that the dissolved ions and precipitated compounds that are leached from the ASS are discharged into the adjacent coastal estuary of Moreton Bay. With knowledge obtained from this PhD study, effective management and treatment systems can be developed and implemented to minimise the impact of these soils on the pond system and the water discharging into natural coastal ecosystem.
43

Υδρογεωλογική περιβαλλοντική μελέτη του καρστικού συστήματος των τριαδικών ανθρακικών λατυποπαγών στο οροπέδιο Παλαιομάνινα-Πεντάλοφος, ΝΔ Αιτωλοακαρνανία

Τσερόλας, Παναγιώτης 28 February 2013 (has links)
Στα πλαίσια της παρούσας διπλωματικής μεταπτυχιακής εργασίας γίνεται υδρογεωλογική, υδροχημική και περιβαλλοντική έρευνα του καρστικού συστήματος των Τριαδικών ανθρακικών λατυποπαγών που εκφορτίζεται στο μέτωπο των πηγών ‘’Λάμπρας’’ ή Αγ. Δημητρίου στην ευρύτερη περιοχή του νότιου Ξηρόμερου, ΝΔ Αιτωλακαρνανίας. Η περιοχή ανήκει στην Ιόνια ζώνη με υπόβαθρο τους Τριαδικούς εβαπορίτες, τα φαινόμενα διαπειρισμού των οποίων έχουν συντελέσει, σε συνδυασμό με το τεκτονικό περιβάλλον της ζώνης, στον σχηματισμό και την ανάπτυξη των Τριαδικών ανθρακικών λατυποπαγών (ΤΑΛ). Επίσης στην περιοχή απαντούν με περιορισμένη εξάπλωση οι σχηματισμοί της μετά-Τριαδικής Ανθρακικής ακολουθίας, που αποτελείται από τους Ιουρασικούς Ασβεστόλιθους ‘’Παντοκράτορα’’, τους ασβεστόλιθους Λιάσιου και τους Κρητιδικούς Ασβεστόλιθους του σχηματισμού της ‘’Βίγλας’’. Απαντούν επίσης μεταλπικοί σχηματισμοί, όπως τεταρτογενείς αποθέσεις με εναλλαγές μαργών και terra rossa, μάργες και αλλουβιακές αποθέσεις. Ο υπό μελέτη καρστικός υδροφόρος αναπτύσσεται στα ΤΑΛ και οριοθετείται προς βορρά από την διαπιστωμένη με γεωφυσικές μεθόδους αναθόλωση των εβαποριτών στην περιοχή Φυτείες και προς τη δύση από την εφίππευση των ΤΑΛ στους Ιουρασσικούς ασβεστόλιθους ‘’Παντοκράτορα’’ των Ακαρνανικών Ορέων. Η περιοχή χαρακτηρίζεται από την ανυπαρξία υδρογραφικού δικτύου Η εκφόρτιση του συστήματος γίνεται από ένα πλήθος (>20) πηγών, στην επαφή των ΤΑΛ με τις τεταρτογενείς αποθέσεις του κάμπου του Λεσινίου. Το μέτωπο των πηγών της ‘’Λάμπρας’’ έχει μήκος ~3km και μέση ετήσια παροχή ~270*106m3/yr. Απαντά επίσης ένα μικρότερο, δυτικό μέτωπο εκφόρτισης με διαφοροποιήσεις στο χημισμό του νερού και μεγαλύτερη συγκέντρωση αλάτων. Οι πηγές έχουν χημισμό Ca-SO4-HCO3, ανάλογο των βασικών χημικών τύπων που προσδιορίστηκαν στα υπόγεια ύδατα ύστερα από την υδροχημική έρευνα. Τα νερά του συστήματος διακρίθηκαν σε δυο κύριες κατηγορίες και δυο δευτερεύουσες: Τους τύπους Ca-SO4-HCO3, Ca- HCO3-SO4 που αποτελούν τον κυρίαρχο τύπο των υδάτων της περιοχής και τους τύπους Ca-SO4 και Ca-Na-SO4-HCO3 που αφορούν τμήματα της περιοχής. Η αυξημένη συγκέντρωση των θειικών ιόντων οφείλεται στην αλληλεπίδραση του νερού με τους εβαπορίτες του υποβάθρου. Ο φυσικός εμπλουτισμός του υπόγειου υδροφόρου υπολογίσθηκε μέσα από την εφαρμογή του μοντέλου APLIS στο ~45% του νερού της βροχής. Η μεγάλη παροχή των πηγών, συγκριτικά και με την μέση ετήσια βροχόπτωση ~850mm/yr οφείλεται στην τροφοδοσία από την πλευρική διήθηση του Αχελώου στο καρστικό σύστημα, κάτι που επιβεβαιώθηκε και από την υδρογεωλογική και υδροχημική έρευνα με ποσοστά συμμετοχής που φτάνουν και το 90% στις πηγές του ανατολικού ορίου του μετώπου και με μέσο όρο συμμετοχής >50%. Μικρότερης σημασίας τροφοδοσία φαίνεται να λαμβάνει χώρα από την λίμνη του Οζερού, στο ΒA όριο της περιοχής μελέτης. Η υδροχημική έρευνα έδειξε επίσης ότι η τροφοδοσία του Αχελώου αποτελεί βασικό παράγοντα της μεταβολής της ποιότητας του υπόγειου νερού και του χημισμού των πηγών. / The purpose of the present thesis is the hydrogeological, hydrochemical and environmental investigation of the karstic system of the Triassic Carbonate Breccia (TCB) which discharges through the spring front of ‘’Lambra’’ and lies in southern Ksiromero, SW Aitoloakarnania. The study area is part of the Ionian Zone and its geological background consists of the Triassic Evaporites. The TCB where formed under the combination of the tectonic and orogenetic setting of the External Hellenides and the diapir phenomena of the Triassic Evaporites. The after-Triassic Carbonate series is also present in the study area, with limited expansion, which consists of the Jurassic Limestones known as ‘’Pantokratoras Limestones’’, the Lias Limestones, the Cretaceus Limestones of the ‘’Vigla’’ formation and the Eocene Limestones. Recent formations are also present: Quartenary sediments with marl and terra rossa variations, marls and alluvial sediments. The karstic aquifer develops through the TCB and its margins are defined by the diapir phenomena in the area of Fities in the North, the Mahalas thrust in the east and the overthrust of the TCB onto the Jurassic ‘Pantokratoras’’ Limestones in the West. The discharge of the karstic system of the TCB consists of numerous springs (>20) in the contact of the TCB with the quartenary deposits of the Lesini Fields. The spring front of Lambra is 3km long with mean annual discharge ~270*106m3/yr. A secondary discharge front is present in the West of the main front with alterations in the water chemism and larger ion concentrations. The hydrochemical type of the springs water is Ca-SO4-HCO3. The hydrochemical investigation provided two major and two minor hydrochemical types for the groundwater: The main types Ca-SO4-HCO3 and Ca- HCO3-SO4 and the secondary types Ca-SO4 and Ca-Na-SO4-HCO3. The elevated concentration of the sulfur anions is due to the interaction of the water with the Triassic Evaporites of the background. The recharge rate of the karstic aquifer was estimated with the application of the APLIS model as the 45% (approx.) of the annual precipitation. The large discharge measurements of the spring front, also compared with the annual precipitation of the study area (~850mm/yr) is due to the side infiltration of the Acheloos River into the karstic system in the Paleomanina area, which was also confirmed after hydrogeological investigations. The participation of the Acheloos water was calculated up to 90% of the spring discharge in the eastern springs of the Lambra front and with a mean participation of over 50% (approx.). Minor participation seems to take place through side infiltrations of the karstic lake Ozeros’ water, in the NE margin of the study area. Hydrochemical investigations also presented that Acheloos’ participation in the aquifer is a main factor of the hydrochemical and quality variations of the groundwater and of the chemism of the springs water.
44

Hidrogeologia e hidroquímica do Sistema Aqüífero Guarani na porção ocidental da bacia sedimentar do Paraná /

Gastmans, Didier. January 2007 (has links)
Resumo: O fluxo das águas subterrâneas no SAG, em sua porção ocidental, é caracterizado pela existência de três áreas de recarga regional, localizadas em Mato Grosso do Sul e Goiás. A partir destas áreas de recarga o fluxo regional é radial direcionado para o centro da Bacia do Paraná. Em algumas porções das zonas de aforamento ocorrem fluxos localizados de descarga. As águas apresentam características químicas que permitem sua classificação em: bicarbonatadas cálcicas ou calco-magnesianas, bicarbonatadas sódicas e bicarbonatadas cloretadas/sulfatadas sódicas, representando, nesta ordem, a sua evolução hidroquímica. Os mecanismos envolvidos nesta evolução são: dissolução de feldspatos e remoção do cimento carbonático do arcabouço mineral dos arenitos, seguido por troca iônica, responsável pelo aumento nas concentrações de sódio e diminuição nas concentrações de cálcio e, finalmente, o enriquecimento em cloreto e sulfato, oriundos dos aqüíferos sotopostos ao SAG. Foram reconhecidas três unidades hidroestratigráficas distintas no SAG: superior, representada pelos arenitos eólicos limpos, da Formação Botucatu, intenuediária, representada por arenitos finos e argilosos, e inferior, por arenitos finos, pouco argilosos, estas duas últimas unidades pertencentes à Formação Pirambóia. / The groundwater flow pattern in the occidental portion of SAG (Guarani Aquifer System) is characterized by the existence of three regional recharge areas located in Mato Grosso do Sul and Goiás states. From these areas ofrecharge the regional flow is radial and directed toward the center of Paraná Sedimentary Basin. Local discharge flows occurs in portions of outcrop regions. The groundwater can be classified as calcium or calcium-magnesium bicarbonate type, sodium bicarbonate type and sodium bicarbonate/chloride/sulphate type, representing in this sequence its hydrochemical evolution. The mechanisms responsible for this evolution are dissolution of feldspars and remova! of the carbonate cement of the sandstones mineral framework, followed by ionic exchange, responsible for the increase in the sodium concentration and decrease of calcium, and, finally, the enrichment in chloride and sulphate derived from underlying aquifers units. Three distinct hydrostratigraphics units in the SAG have been recognized: the upper unit is represented by aeolian sandstones from Botucatu Formation, the intermediate, represented by the fine and argillaceous sandstones, and the lower unit is constituted by fine sandstones with low content in clays, these last two units belong to the Pirambóia formation. / Orientador: Chang Hung Kiang / Coorientador: Ian Hutcheon / Banca: Osmar Sineli / Banca: Ricardo César Aoki Hirata / Banca: Alexandre Campane Vidal / Banca: Ernani Francisco da Rosa Filho / Doutor
45

Hidrogeologia e hidroquímica do Sistema Aqüífero Guarani na porção ocidental da bacia sedimentar do Paraná

Gastmans, Didier [UNESP] 19 April 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-04-19Bitstream added on 2014-06-13T20:43:11Z : No. of bitstreams: 1 gastmans_d_dr_rcla.pdf: 6127390 bytes, checksum: ab710341c81fc6a1a52c3f6d1d493132 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / O fluxo das águas subterrâneas no SAG, em sua porção ocidental, é caracterizado pela existência de três áreas de recarga regional, localizadas em Mato Grosso do Sul e Goiás. A partir destas áreas de recarga o fluxo regional é radial direcionado para o centro da Bacia do Paraná. Em algumas porções das zonas de aforamento ocorrem fluxos localizados de descarga. As águas apresentam características químicas que permitem sua classificação em: bicarbonatadas cálcicas ou calco-magnesianas, bicarbonatadas sódicas e bicarbonatadas cloretadas/sulfatadas sódicas, representando, nesta ordem, a sua evolução hidroquímica. Os mecanismos envolvidos nesta evolução são: dissolução de feldspatos e remoção do cimento carbonático do arcabouço mineral dos arenitos, seguido por troca iônica, responsável pelo aumento nas concentrações de sódio e diminuição nas concentrações de cálcio e, finalmente, o enriquecimento em cloreto e sulfato, oriundos dos aqüíferos sotopostos ao SAG. Foram reconhecidas três unidades hidroestratigráficas distintas no SAG: superior, representada pelos arenitos eólicos limpos, da Formação Botucatu, intenuediária, representada por arenitos finos e argilosos, e inferior, por arenitos finos, pouco argilosos, estas duas últimas unidades pertencentes à Formação Pirambóia. / The groundwater flow pattern in the occidental portion of SAG (Guarani Aquifer System) is characterized by the existence of three regional recharge areas located in Mato Grosso do Sul and Goiás states. From these areas ofrecharge the regional flow is radial and directed toward the center of Paraná Sedimentary Basin. Local discharge flows occurs in portions of outcrop regions. The groundwater can be classified as calcium or calcium-magnesium bicarbonate type, sodium bicarbonate type and sodium bicarbonate/chloride/sulphate type, representing in this sequence its hydrochemical evolution. The mechanisms responsible for this evolution are dissolution of feldspars and remova! of the carbonate cement of the sandstones mineral framework, followed by ionic exchange, responsible for the increase in the sodium concentration and decrease of calcium, and, finally, the enrichment in chloride and sulphate derived from underlying aquifers units. Three distinct hydrostratigraphics units in the SAG have been recognized: the upper unit is represented by aeolian sandstones from Botucatu Formation, the intermediate, represented by the fine and argillaceous sandstones, and the lower unit is constituted by fine sandstones with low content in clays, these last two units belong to the Pirambóia formation.
46

Estudo hidroquímico das águas subterrâneas do Aquífero Furnas na região sudeste do estado de Mato Grosso

Magalhães, Aparecida de 10 November 2015 (has links)
Submitted by Jordan (jordanbiblio@gmail.com) on 2017-03-14T12:19:02Z No. of bitstreams: 1 DISS_2015_Aparecida de Magalhaes.pdf: 2129007 bytes, checksum: 2169c99d2d815a6862e311324434d691 (MD5) / Approved for entry into archive by Jordan (jordanbiblio@gmail.com) on 2017-03-14T16:00:01Z (GMT) No. of bitstreams: 1 DISS_2015_Aparecida de Magalhaes.pdf: 2129007 bytes, checksum: 2169c99d2d815a6862e311324434d691 (MD5) / Made available in DSpace on 2017-03-14T16:00:01Z (GMT). No. of bitstreams: 1 DISS_2015_Aparecida de Magalhaes.pdf: 2129007 bytes, checksum: 2169c99d2d815a6862e311324434d691 (MD5) Previous issue date: 2015-11-10 / As águas subterrâneas constituem uma grande reserva de água doce e por isso seu estudo é importante em relação aos aspectos qualitativos e quantitativos, pois a disponibilidade dos recursos hídricos subterrâneos para determinados tipos de uso dependem do conhecimento da sua característica hidroquímica. Este trabalho teve por objetivo geral realizar um estudo hidroquímico das águas subterrâneas do Aquífero Furnas na região sudeste do Estado de Mato Grosso, com vistas à classificação e caracterização química do aquífero. Assim foi possível verificar a adequação da água para o consumo humano, para agricultura ou para fins industriais; bem como compreender as interações rocha-água ou algum tipo de influência antrópica. Foram coletadas amostras de água subterrânea de vinte dois poços tubulares profundos da região. Os resultados permitiram as seguintes considerações: O Aquífero Furnas é do tipo confinado, possui excelentes condições de armazenamento e circulação das águas subterrâneas. Ocorre na região os fenômenos de artesianismo e termalismo, predominando águas mesotermais e termais, embora em alguns locais as águas sejam hipertermais. As águas subterrâneas estudadas possuem baixas concentrações de sais dissolvidos, sendo de boa qualidade para a agricultura e pecuária. A baixa salinidade provavelmente está relacionada com a ocorrência de minerais pouco solúveis na Formação Furnas, principalmente quartzo e feldspatos alcalinos. Das vinte duas amostras analisadas para o íon ferro, oito apresentaram concentração superior ao limite máximo permissível para o consumo humano, porém todas estão abaixo dos limites máximos permissíveis para a irrigação. Com relação aos íons, o ânion mais comum é o bicarbonato e o cátion mais comum é o magnésio, o que mostra o controle litoquímico exercido pelas rochas da Formação Furnas. O tipo químico dominante, permitiu classificar as amostras de água da região, em águas bicarbonatada cálcica ou magnesiana, existindo a ocorrência de três poços com águas do tipo bicarbonatada sódica. O principal tipo de água observada na região foi a bicarbonatada magnesiana. / Groundwater is a major fresh water reserve and therefore its study is of fundamental importance in relation to the qualitative and quantitative aspects, since the availability of groundwater resources for certain types of use depend on the knowledge of its characteristic hydrochemistry. The main objetctive of this study was to conduct a hydrochemical study of groundwater in the aquifer Furnas in southeastern state of Mato Grosso, with a view to classification and chemical differentiation of the aquifer. Thus it was possible to prove if the water quality is suitable for human consumption, agricultural or industrial purposes; and understand the rock-water interactions or any kind of human influence. For this, we collected water samples from twenty two deep wells in the region. The results led to the following considerations: The Aquifer Furnas is confined, has excellent conditions of storage and movement of groundwater. The phenomena of artesianismo and hydrotherapy occursinthe region, predominating mesothermal and thermal waters, although in some places the water is hyperthermal. Groundwater studied have low concentrations of dissolved salts, and good quality for agriculture and livestock. The low salinity is probably related to the occurrence of poorly soluble minerals in Furnas Formation, mainly quartz and feldspar. Of the twenty two samples analyzed for the iron ion, eight had higher concentration than the maximum permissible limit for human consumption, but all are below the maximum permissible limits for irrigation. With respect to ions, the most common anion is bicarbonate and the cation is magnesium, which shows the litochemical control by rocks of the Furnas Formation. The dominant chemical types, allowed to classify water samples in the region as calcic or magnesian bicarbonate waters, and the occurrence of three wells with type bicarbonate sodic waters. The main type of water observed in the region was magnesian bicarbonate.
47

Estudo hidroquímico do complexo Termal de Caldas Novas (GO), Brasil / Hydrochemical study of the Caldas Novas Thermal Complex (GO), Brazil / Étude hydrochimique du Complexe Thermal de Caldas Novas (GO), Brésil

Lunardi, Marina [UNESP] 07 October 2016 (has links)
Submitted by Marina Lunardi (marina.lunardi@gmail.com) on 2016-11-17T15:31:55Z No. of bitstreams: 1 merged.pdf: 4468328 bytes, checksum: ee55f7e9cf76df935b0c25c2af283b21 (MD5) / Approved for entry into archive by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br) on 2016-11-21T13:34:36Z (GMT) No. of bitstreams: 1 lunardi_m_me_rcla.pdf: 4468328 bytes, checksum: ee55f7e9cf76df935b0c25c2af283b21 (MD5) / Made available in DSpace on 2016-11-21T13:34:36Z (GMT). No. of bitstreams: 1 lunardi_m_me_rcla.pdf: 4468328 bytes, checksum: ee55f7e9cf76df935b0c25c2af283b21 (MD5) Previous issue date: 2016-10-07 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A cidade de Caldas Novas, no Estado de Goiás, abriga o maior complexo termal do planeta não vinculado ao vulcanismo ou outros tipos de magmatismo. O controle estrutural desta região comporta fraturas suficientemente abertas e profundas por onde as águas podem atingir 1000 metros de profundidade. Tais águas são extraídas principalmente por meio de poços tubulares, com explotação dos Sistemas Aquíferos Paranoá e Araxá, a temperaturas superiores a 59°C. Com a crescente demanda de recursos hídricos, a exploração de águas subterrâneas torna-se uma alternativa atraente para o abastecimento público, em virtude da sua abundância, qualidade e baixo custo de captação. Em Caldas Novas, devido ao crescimento populacional das últimas décadas e ao aumento no número de turistas na região, um consumo desordenado dos recursos hídricos subterrâneos resultou no rebaixamento severo dos níveis piezométricos. A sobrevivência destes reservatórios termais depende da infiltração de água da chuva para a renovação do manancial termal, porém, com a falta de manejo sócio-ambiental e o alto risco de contaminação que o município apresenta, em virtude à pouca espessura dos materiais inconsolidados, estes aquíferos podem estar ameaçados. O presente trabalho realizou uma caracterização hidroquímica no Complexo Termal de Caldas Novas, abrangendo parâmetros radioativos, cuja descrição na literatura ainda é escassa. Além disso, tendo em vista o incremento das atividades turísticas da região, existe a necessidade de levantamentos periódicos dos aspectos químicos destas águas, sendo este trabalho uma contribuição nesse sentido. / The city of Caldas Novas, State of Goiás, Brazil, holds the largest thermal water complex in the planet not associated to volcanism or other kinds of magmatism. It’s structural control allows the fractures to be wide and deep enough so the waters can reach 1000 meters depth. These waters are extracted mainly by deep wells, from the exploitation of the Paranoá and Araxá Aquifer Systems, emerging at temperatures higher than 59°C. With a growing demand for water resources, groundwater exploration became an attractive alternative for public supply, due to its abundance, quality and low abstraction cost. In Caldas Novas, due to the population growth over the last decades and the increasing number of tourists, a disordered groundwater consumption drawndown the water levels. In order to survive, these reservoirs depends on rainwater infiltration rates to replenish the thermal springs, however, the lack of environmental management and the high risk of contamination, due to the unconsolidated materials thinness, may threaten the thermal aquifer. This thesis was based on the hydrochemical characterization of Complexo Termal de Caldas Novas waters, including radioactive parameters, whose descriptions in the literature are still scarce. Besides, concerning the prospective increase on touristic activities, physicochemical water analyses are periodically required, being this thesis a contribution for that matter.
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Hydrochemické charakteristiky povrchových vod malých povodí v oblasti horní Stropnice / Chemism of surface waters in small watersheds of the upper part of Stropnice river

BAXOVÁ, Iva January 2008 (has links)
Chemism of surface waters in four small watersheds of upper part of Stropnice River was studied from 2005 till 2007. The aim of this work was to consider the relations between different types of land-use and chemism of surface water. There were observed the concentrations of main ions and carbon in the surface waters in eight sample places which were measured monthly. The results were analysed with Repeated Measures ANOVA and Tukey HSD post hoc analyse was used for detail description. There were no differences between surface water chemisms in the upper parts of four streams. Watersheds in the upper parts are similar and can be considered as a close to natural landscape. In the lower parts of four streams which discharged different types of cultural landscape, significant differences in the water chemisms were found. Significant differences were observed also in the three streams in the water chemisms between upper and lower parts of the watersheds as a result of the land-use change. In the stream where land-use does not change between upper and lower parts of watershed, no differences in the water chemisms were observed. The results show positive relation between the chemism of surface water and land-use and possible effect of human impact on landscape ecosystem and its hydrological component.
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Padrões hidroquímicos e isotópicos do sistema aquífero serra geral do Município de Carlos Barbosa, região nordeste do estado do Rio Grande do Sul

Bortolin, Taison Anderson January 2014 (has links)
Este trabalho buscou avaliar a existência de diferentes padrões hidroquímicos e isotópicos dos aquíferos fraturados do Sistema Aquífero Serra Geral (SASG), relacionando esses padrões com as profundidades das entradas de água. O estudo foi desenvolvido a partir do inventário e cadastramento de poços tubulares existentes na região do município de Carlos Barbosa - RS, do levantamento e interpretação de dados geológicos e hidrogeológicos, além da coleta e análise de amostras de água de poços tubulares que estão em operação e são utilizados pela companhia de abastecimento CORSAN. Para este trabalho foram utilizadas informações hidroquímicas e isotópicas da água de 12 poços tubulares e 3 fontes, além de análise isotópica mensal da água da chuva. A análise dos resultados foi realizada através dos diagramas de Piper, Schoeller e Stiff, além de análise estatística de agrupamento a fim de verificar padrões semelhantes entre os pontos amostrados. Os resultados obtidos permitiram evidenciar que a maioria dos poços apresentam profundidade de até 150 metros com vazões médias que variam de 5 a 20 m³/h, localizados em zonas de média e alta densidade de fraturas, as quais possuem orientação preferencial para noroeste. Quanto à hidroquímica, as águas que circulam por esses aquíferos são do tipo bicarbonatadas cálcicas ou magnesianas, predominando as águas bicarbonatadas mistas e cálcicas, com pequenas variações em relação à concentração dos íons e suas razões iônicas. Essas características hidroquímicas são típicas de águas que circulam por estruturas de rochas vulcânicas ácidas e indicam um baixo tempo de residência, sendo as concentrações variáveis com as profundidades das entradas da água. A avaliação entre a correlação de padrões hidroquímicos com a profundidade das entradas de água permitiu a identificação de dois grupos. O primeiro grupo é caracterizado por poços que apresentam entradas de água localizadas em profundidades inferiores a 30 metros e águas com baixa concentração de íons. No segundo grupo estão inseridos poços cujas entradas de água estão localizadas entre 50 e 112 metros e apresentam águas com uma maior concentração de íons como cálcio, sódio, bicarbonatos e maiores valores de condutividade e sólidos totais dissolvidos. A explicação dessas diferenças está relacionada com a circulação de água e com tempo de interação água-rocha que ocorre de forma diferente dependendo da profundidade das entradas de água. A análise de isótopos das águas de poços, fontes e da água da chuva apresentam semelhanças isotópicas indicando que água subterrânea pode ser caracterizada como originada por infiltração da precipitação nas áreas de recarga. Por fim, a caracterização hidroquímica e isotópica indicam que as águas subterrâneas dessa região apresentam baixo grau de mineralização e baixo tempo de residência, sendo que as exceções foram encontradas em poços que possuíam entradas de água mais profundas. / This study aimed to evaluate the existence of different hydrochemical and isotopic patterns of fractured aquifers of Serra Geral Aquifer System (SGAS), relating these patterns with depths of water intakes. The study was developed from the inventory and registration of wells in the region of Carlos Barbosa - RS, the survey and interpretation of geological and hydrogeological data, and the collection and analysis of samples of water from wells that are in operation and are used by the supply company CORSAN. Hydrochemical and isotopic information from 12 wells and 3 water sources were used for this work, in addition to monthly isotopic analysis of rainwater. The analysis was performed using diagrams as Piper, Schoeller and Stiff, and statistical cluster analysis to verify similar patterns between the sampling points. The results have highlighted that most wells have depths up to 150 meters with average flow rates ranging from 5 to 20 m³/h, located in areas of medium and high density of fractures, which have preferential orientation to the northwest. As for hydrochemistry, water circulating through these aquifers are the calcic or magnesian bicarbonate type , predominantly mixed and calcic bicarbonate waters, with minor variations in the concentration of ions and their ionic reasons. These hydrochemical characteristics are typical of waters that circulate structures and acidic volcanic rocks indicate a low residence time, and the varying concentrations with depths of water inputs. The evaluation of the correlation between patterns hydrochemical with water entry's depth allowed the identification of two groups. The first group is characterized by wells that have water intakes located bellow than 30 meters and waters with low concentration of ions. In the second group are inserted into wells whose water inlets are located between 50 and 112 meters and water present in a higher concentration of ions such as calcium, sodium, bicarbonates and higher values of conductivity and dissolved solids. The explanation of these differences are related to the circulating water and water - time interaction rock occurs differently depending of water entry's depth. Analysis of isotopes of water wells and sources of rainwater present isotopic similarities indicating that groundwater can be characterized as caused by infiltration of rainfall areas recharging. Finally, the hydrochemical and isotopic characterization indicate that the groundwater in this region have low grade mineralization and low residence time, with the exceptions were found in wells that had water intakes deeper.
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HidroquÃmica do aquÃfero costeiro do municÃpio de Itarema - Cearà / Hidrochemistry of the coast aquifer of the county of Itarema - Ceara

Ludmila Prazeres das Flores Oliveira Rocha 21 August 2015 (has links)
CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel Superior / A Ãrea do estudo compreende a Zona Costeira do municÃpio de Itarema, distante 230 km de Fortaleza, Litoral Oeste do Estado do CearÃ. Nesta Ãrea sÃo raros os trabalhos que visam o estudo tanto das Ãguas superficiais quanto subterrÃneas. A explotaÃÃo da Ãgua subterrÃnea tende a aumentar na Ãrea, devido ao aumento na densidade demogrÃfica, trazendo com isso riscos potenciais de contaminaÃÃo da Ãgua. Nesse sentido torna-se importante avaliar a qualidade da Ãgua e os mecanismos de recarga para a preservaÃÃo e uso racional dessa. Foram coletadas amostras de Ãguas superficiais e subterrÃneas e realizadas medidas de variÃveis fÃsicas, quÃmicas e bacteriolÃgicas durante nove (9) campanhas de amostragem, empregando mÃtodos titulomÃtricos, espectrofotomÃtricos e potenciomÃtricos. As Ãguas subterrÃneas apresentam-se predominantemente como doce. E as Ãguas superficiais, segundo classificaÃÃo IQA-CETESB, encontram-se boas para abastecimento pÃblico. A contaminaÃÃo por nitrato em Ãguas subterrÃneas, mesmo em baixas concentraÃÃes, evidencia aÃÃes antrÃpicas pontuais, nÃo caracterizando efeito sazonal. O estudo dos elementos traÃo ora apresentou teores de alguns elementos mais elevados que os VMP previstos em legislaÃÃo vigente, ora nÃo. No entanto, estes nÃo estÃo relacionados à possÃvel contaminaÃÃo por agrotÃxicos, segundo os resultados das anÃlises para quantificaÃÃo e qualificaÃÃo de organofosforados. Tais resultados podem estar associados ao tipo de construÃÃo dos poÃos, à profundidade destes, aos descartes de materiais diversos e atà mesmo formaÃÃo rochosa da Ãrea. Com relaÃÃo ao estudo dos isÃtopos, prevalecem Ãguas leves durante os perÃodos chuvosos Ãs coletadas nos perÃodos de estiagem, o que caracteriza efeito quantidade de chuva. A recarga do aquÃfero (Ie) na Ãrea, foi estimada em 368,73 mm, representando 31% da PPT. E por fim, o estudo de vulnerabilidade à contaminaÃÃo do aquÃfero atravÃs da aplicaÃÃo do mÃtodo DRASTIC apresentou que em 79% da Ãrea, predomina vulnerabilidade moderada e alta. Isso exige maiores cuidados com o uso e ocupaÃÃo do solo, de forma a evitar danos aos mananciais subterrÃneos / The study area covers the coastal area of the county of Itarema, 230 km from Fortaleza, West coast of the State of CearÃ. In this area, rare are the works aimed at the study of both surface water and groundwater. Although the exploitation of groundwater tends to increase in the area, due to the increase in population density, bringing with it potential risks of water contamination. Therefore it is important to assess the quality of the water and recharge mechanisms for the preservation and rational use of these resources. We collected samples of surface water and groundwater and carried out measurements of physical, chemical and bacteriological variables for all nine (9) sampling campaigns, using titrimetry, spectrophotometric, potenciometric and atomic absorption spectrometry methods. Groundwater is predominantly fresh water. And surface waters, according to the IQA-CETESB classification are good for public supply. Nitrate contamination in groundwaters, even at low concentrations, shows anthropic actions, not featuring seasonal effect. The study of trace elements sometimes presented some elements with higher levels than the VMP estipulated expected in the current legislation. However, these are not related to possible contamination by agrochemicals, according to the results of the analyses for quantification and qualification of organophosphates. Such results can be associated with the construction of the wells, their depth, waste deposition of various materials and even rock formations in the area. With respect to the study of isotopes, prevail lighter waters during the rainy periods than those collected during periods of drought, which characterizes the amount effect in rainfall. Through the water balance was estimated that, on average, about 31% of the total annual precipitation recharge the aquifers. Finally, the study of vulnerability to contamination of the aquifer, through the DRASTIC method, showed that in 79% of the area prevail moderate and high vulnerability. This requires great care with the use and occupation of the soil, in order to prevent damage to groundwater resources

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