Thesis (M. S.)--Civil and Environmental Engineering, Georgia Institute of Technology, 2008. / Committee Chair: Aral, Mustafa; Committee Member: Guan, Jiabao; Committee Member: Pavlostathis, Spyros; Committee Member: Uzer, Turgay; Committee Member: Yiacoumi, Sotira.

Maîtrise (M.Sc.T.)--Université du Québec à Chicoutimi, 2001. / Document électronique également accessible en format PDF. CaQCU

Orientador: Wanilson Luiz Silva / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Geociencias / Made available in DSpace on 2018-08-10T23:28:06Z (GMT). No. of bitstreams: 1 Campaner_VeridianaPolvani1981-_M.pdf: 789477 bytes, checksum: 2fc8ab44d662b02cf37a6481c9ac9f7d (MD5) Previous issue date: 2008 / Resumo: Este estudo foi desenvolvido em área de mineração de carvão, na região de Figueira (PR). A primeira parte deste trabalho investigou processos físico-químicos da drenagem ácida antes e após o tratamento com CaO e sua evolução em drenagem natural em área com presença de rochas calcárias. Os resultados mostraram um incremento no pH da drenagem ácida após o tratamento (de 3,2 para 4,6) e redução nas concentrações dos constituintes analisados. A evolução deste efluente ácido na rede de drenagem local resultou em um novo sistema físico-químico, inicialmente com pH 6,4 e menores níveis de Eh e dos constituintes químicos, em especial para SO4 2¯ (1578 mg L¯1), Al (0,07 mg L¯1), Fe (17,8 mg L¯1) e Mn (2,48 mg L¯1). Entretanto, as concentrações destes constituintes foram ainda menores nesta drenagem com incremento do pH para 10,8, exceto para Al. O incremento na concentração de Al (de 0,07 mg L¯1 para 0,63 mg L¯1) é atribuído à lixiviação de minerais silicáticos sob condições alcalinas, as quais favoreceram a solubilização do metal. Este aumento do pH pode ser conseqüência de rochas calcárias da região que se encontram a partir de 10,5 m de profundidade. Águas subterrâneas que alimentam a drenagem local devem contribuir com o incremento das concentrações de HCO3¯ até que as condições de equilíbrio do sistema carbonático sejam rompidas com o excesso de CO3 2¯, aumentando o pH para 10,8. Neste ponto ocorreram condições físico-químicas favoráveis para a remoção de Mn, um dos problemas encontrados em processos de neutralização de drenagem ácida. A segunda parte deste trabalho avaliou as características geoquímicas de drenagens ácidas desta região e seus impactos em águas e em sedimentos de corrente. Os resultados mostraram que as drenagens ácidas são geradas tanto em galerias de extração do minério como em depósitos de rejeito, com pH entre 3,2 e 4,1. Estas últimas drenagens apresentaram as maiores concentrações dos elementos investigados, com destaque para o As (0,25 mg L¯1 a 0,68 mg L¯1). O impacto destas soluções ácidas nos rios da área foi pouco significativo. As concentrações de SO4 2¯, Al, Cd, Co, Fe, Mn, Ni e Zn (nas proximidades de minas ativas) e SO4 2¯, Al, Cd, Fe, Mn e Zn (nas proximidades de depósitos de rejeito e minas desativadas) excederam levemente os padrões brasileiros de qualidade para águas superficiais. As águas subterrâneas de poços de monitoramento das atividades mineiras apresentaram o mesmo intervalo de pH e concentrações químicas semelhantes aqueles das drenagens ácidas, revelando o seu comprometimento. Entretanto, as amostras de águas subterrânea e fluvial de abastecimento público municipal revelaram pH entre 7,2 e 7,5 e baixas concentrações dos componentes analisados. A geoquímica de sedimentos de corrente mostrou maiores fatores de enriquecimento para As, Cd, Mn, Ni e Zn, e foram restritos aos locais mais róximos das fontes geradoras de drenagens ácidas. Neste caso, os processos de sedimentação ocorreram em zonas de mistura das soluções ácidas com águas fluviais, as quais contribuíram para a neutralização da acidez e a conseqüente precipitação das espécies químicas / Abstract: This study was developed in coal mining area, region of Figueira (PR). The first part of this study searched physico-chemical processes of the acid mine drainage before and after the neutralization with CaO and the evolution of these acid waters in natural stream in area with presence of carbonatic rocks. The results showed an increasing in pH of acid mine drainage after the treatment (from 3.2 to 4.6) and a reduction in concentrations of analyzed constituents. The evolution of these acid waters within the tributary stream resulted in new physicochemical system, initially with pH 6.4 and lower levels of Eh and of chemical constituents, particularly SO4 2¯ (1578 mg L¯1), Al (0.07 mg L¯1), Fe (17.8 mg L¯1) and Mn (2.48 mg L¯1). However, the concentrations of these constituents were lower in natural stream with increment of pH to 10.8, except Al. Aluminum increasing concentration (from 0.07 mg L¯1 to 0.63 mg L¯1) during this evolution seems to be related to an input of Al-enriched waters due the leaching of silicate minerals in alkaline conditions. This increasing in pH can be resulted from local bedrock that contains limestone from 10.5 meters depth. Groundwater input to the natural stream contributes to the increase in HCO3¯ concentrations until the conditions of carbonate system equilibrium are broken with the excess CO3 2¯, increasing the water pH to 10.8. In this point, favorable conditions happened to the removal of Mn, a problem found in neutralization process of acid drainage. The second part of this work evaluated the geochemistry characteristics of acid drainage in this region, and the impacts in waters and surface sediments. The results showed that the acid drainage is generate as much in coal extraction gallerias as in tailing deposits, with pH from 3.2 to 4.1. These last drainages showed the higher concentrations of analyzed elements, especially As (from 0.25 mg L¯1 to 0.68 mg L¯1). The impact of these acid solutions to the rivers in the area had little meaning. The concentrations of SO4 2¯, Al, Cd, Co, Fe, Mn, Ni and Zn (near to the active mines) and SO4 2¯, Al, Cd, Fe, Mn and Zn (near the tailing deposits and abandoned mines) exceeded the Brazilian quality standards to stream waters. Groundwater monitoring wells from the active mines showed the same interval of pH and chemical concentrations were similar to those of acid drainages, which represented significant impacts. However, the stream water and groundwater samples of municipal public provision revealed pH from 7.2 to 7.5 and low concentrations of analyzed components. The geochemistry of stream sediments showed higher enrichment factors to As, Cd, Mn, Ni e Zn, and were restrict to the nearest places of acid drainages generation source. In this case, the sedimentation processes happened in the mixing zone of the acid solutions with stream waters, which caused the neutralization of acidity and the precipitation of the chemical species / Mestrado / Geologia e Recursos Naturais / Mestre em Geociências

Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-03-30T12:41:23Z No. of bitstreams: 1 eliesecristinadeoliveira.pdf: 658851 bytes, checksum: 68287f985bb39c1fe440518b3cd33589 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-04-03T18:49:19Z (GMT) No. of bitstreams: 1 eliesecristinadeoliveira.pdf: 658851 bytes, checksum: 68287f985bb39c1fe440518b3cd33589 (MD5) / Made available in DSpace on 2017-04-03T18:49:19Z (GMT). No. of bitstreams: 1 eliesecristinadeoliveira.pdf: 658851 bytes, checksum: 68287f985bb39c1fe440518b3cd33589 (MD5) Previous issue date: 2008-06-18 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O entendimento da dinâmica biogeoquímica é um ponto central na tentativa de, racionalmente, manejar recursos e minimizar os impactos gerados por atividades antrópicas nos sistemas aquáticos amazônicos, especialmente devido à importância dessa região no ciclo global do carbono. O presente estudo pretende contribuir com esta temática avaliando a composição isotópica e química da água na várzea de Curuai (PA). As amostras de água foram coletadas na superfície da coluna d’água no Lago Grande em três períodos distintos do ciclo hidrológico. Os valores de concentrações e de δ13C (-28,4 a -23,3‰) e δ15N (2,0 a 5,0‰) para os sólidos fino em suspensão (SFS) revelaram mudanças consideráveis na quantidade e na composição da matéria orgânica ao longo do ciclo hidrológico. Enquanto no período de enchente a planície recebe materiais das áreas laterais e rio Amazonas, nos períodos de cheia e vazante as contribuições autóctones podem ser registradas com maior intensidade no sinal isotópico do SFS. A composição isotópica do carbono inorgânico dissolvido (CID) também parece refletir a ciclagem da matéria orgânica na várzea. A composição química da água, por sua vez, é muito similar à do rio principal e está mais intensamente relacionada ao pulso de inundação e à litologia na bacia hidrográfica. Foi observada uma maior influência da drenagem local no período de vazante, especialmente sobre as concentrações de Cl- e HCO-3. Este estudo evidencia o controle do pulso de inundação e da hidrodinâmica interna sobre a química e a composição da matéria orgânica nos sistemas de várzeas da bacia Amazônica. / The understanding of the biogeochemical dynamics is a central point for the implementation of sustainable resources management and to minimize the impacts of human activity over the Amazonian aquatic systems. It becomes more critic when we consider the role of Amazon region plays in the global carbon cycle. The present study tries to contribute to this approach by examining the seasonal variation in isotopic and chemical composition of the water in Lago Grande de Curuai floodplain, Brazil, a complex system of lakes linked to the Amazon River by several channels. Water samples were taken from surface of the Lago Grande in three different phases of the hydrological cycle. The δ13C (from -28,4 to -23,3‰) and δ15N (from 2,0 to 5,0‰) values and concentrations of the fine suspended sediments (FSS) revealed considerable variability in the lake organic matter abundance and composition. These patterns are a result of system internal functioning along the hydrological cycle. If on the one hand water and material inputs from the catchment area and Amazon river do influence the isotopic signal of the FSS the during rising water, on the other hand an effect of the primary production seems to be recovered in the FSS during periods of high water and falling. Additionally, the DIC isotopic composition seems to reflect the seasonality in organic matter inputs to the “varzea”. The water chemical composition is quite similar to that of the main river and was probably more related to the flood pulse and drainage basin lithology. A greater influence of the local drainage was observed during the falling water period, especially over the Cl- and HCO-3 concentrations. This work brings evidences that the flood pulse and the internal dynamics of the floodplains in the Amazon basin are ultimately decisive to its biogeochemistry.

M.Sc. (Geology) / Despite Chrissie Lake being South Africa's largest freshwater lake, the chemistry of this lake and the surrounding lakes and pans in the Mpumalanga Lake District has never been studied in detail. These closed systems show varying chemistry while being in very close proximity to one another, adding to the uniqueness of this area where pans, usually typical of arid regions, are found in a humid area. The factors affecting the water chemistry of these lakes needed to be identified and explained. In order to evaluate the water chemistry in this unique environment, water samples were taken at the end ofthe wet and dry seasons, in April and September 2007 respectively. The major pans were sampled, as were adjacent fountains or springs, indicative of the perched groundwater aquifers found in this area, as well as borehole water from the surrounding farms. Alkalinity was determined by manual titration upon returning from the field while pH and conductivity measurements were performed on site. Major cations and anions were analysed for using ICP-OES and Ion Chromatography respectively. Sediment samples were collected from the floor of each pan in the summer sampling and the mineralogy determined by X-ray diffraction (XRD). During September 2007 sampling, precipitates found on the floors and banks of the pans were also collected and analysed using XRD, to identify mineral species precipitating from solution. Initial results show pH values ranging from 7.0-10.5 for the lakes and pans and from 6.0-8.0 for the borehole water and springs. Values as low as 100 mglL Total Dissolved Solids (TDS) were measured for the pans, with maximum values set at 10 giL for the most saline of these bodies of water in the wet season and as much as 90glL for a pan almost completely dried out in the dry season. The water in the closed pan systems are dominated by Na-CI- HCO~ and have varying concentrations of major cations. The dilute spring waters have TDS values ranging from 20-200 mg/L, indicating the excellent quality of the groundwater, while some boreholes reach values of I 000 mg/L TDS showing possible linkage to pans or leaking of the pan water into the surrounding strata. To understand the main processes affecting the inorganic chemistry of the surface and shallow groundwater of this area, major ions were plotted against chloride. The latter behaves conservatively and can thus be used to monitor the behaviour of solutes in the pan waters. These plots illustrate that the dominant process in the evolution of the waters in the MLD is evaporative concentration. Removal of species through mineral precipitation is clearly seen; carbonate species...

Increasing attention is being given to acid sulphate soils wherever they occur. The problems that leaching sulphate soils gives with significant lowerings of pH and mobilization of heavy metals influence large spectra of our society from fisheries to agriculture to construction. Mapping these soils is consequently of great importance and the methods of doing this is very much lacking in function and precision. This study was therefore carried out to investigate whether conductivity in running water can be used as a simple instrument to identify acid sulphate soils in the catchment. 31 coastal streams in the county of Västerbotten were analyzed for different catchment properties such as occurence of marine sediments and basic water chemistry including conductivity and sulphate. Sulphate proved to be the dominant factor controling conductivity in most streams, constituting up to 90 % of the anions. The results also showed that the concentrations of sulphate correlated to 67 % with marine sediments in the catchment. Where conductivity values exceeded 90 µS/cm the influence of acid sulphate soils could be determined for certain. The major conclusion drawn from this study is that high conductivity values serves as a reliable indicator of leaching acid sulphate soils whereas lower values can not exclude them. / flisik

Detta examensarbete syftar till att studera hur olika vattenkemiska parametrar förändras då vattnet rinner genom sjöar i Emåns avrinningsområde. Vattenkemidata hämtades från Sveriges lantbruksuniversitets databank. Genom att använda ArcGIS verktyget STARS, Spatial Tools for the Analysis of River Systems, kunde en hydrologisk nätverksmodell byggas upp. De vattenkemiska parametrarna som analyserades var pH, färgtal, absorbans filtrerad (Abs), syraneutraliserande förmåga (ANC), oorganiskt kväve (IN), organiskt kväve (ON), total kväve (TN), total organisk kol (TOC), total fosfor (Tot-P) samt fosfat (PO4-P).  Tillvägagångsättet i examensarbetet har varit ett statistiskt sätt att bearbeta och kvantifiera data mellan sjöar och vattendrag. Inga kemiska, fysikaliska eller biologiska processer har studerats. Detta examensarbete ger en inblick i de möjliga samband som finns mellan sjöar och vattendrag i landskapet. Geostatistiska modeller är viktiga verktyg för att förstå hur kemiska och biologiska processer verkar i sjöar och vattendrag. När geostatistiska modeller analyseras används olika avståndsmodeller där dessa kan ge en djupare förståelse för vad som händer mellan miljöövervakningsstationerna. Vid bestämning av färdväg och avstånd mellan miljöövervakningsstationerna är euklidiskt avstånd (fågelvägen) eller ett hydrologiskt avstånd (fiskvägen) de vanligaste. Dessa avstånd kan antingen definieras som symmetriskt eller asymmetriskt avstånd. Studier har visat att det finns brister i hur sjöar skall analyseras på ett korrekt sätt i modellerna. I den här studien används längden mellan sjöars in- och utlopp, sjölängd (SL), som beräknades för samtliga sjöar och jämfördes med avstånden ovan för att urskilja effekterna av sjöar. Arean på sjöar och våtmarker, SV, beräknades också till varje miljöövervakningsstation. Statistiskanalysering utfördes med vattenkemidata från augusti månad från åren 2010 och 2013. Under augusti månad inhämtades data från samtliga miljöövervakningsstationer. Skillnaden i månadsmedelflöde var störst åren 2010 och 2013 jämfört med övriga år. Resultatet av analyseringen visade att Abs, färgtal, IN, ON, PO4-P, TN, TOC och Tot-P hade en negativ korrelation mot SL och SV area uppströms miljöövervakningsstationerna. pH hade en positiv korrelation och det fanns ingen signifikant korrelation för ANC. SL var starkt korrelerad med sjöegenskaperna area, volym, max- och medeldjup. Baserat på samtliga ovannämnda resultat drogs slutsatsen att sjöar hade en större påverkan på de vattenkemiska parametrarna än vattendragen. Ur ett landskapsperspektiv ökade koncentrationen av de vattenkemiska parametrarna längs med vattendragen men koncentrationen minskade när vattnet strömmade igenom sjöar. Att använda SL som avståndsmätning i sjöar är ett enkelt och bra sätt att beskriva vattnets väg genom sjöar där stark korrelation fanns mellan SL och sjöegenskaperna. / The aim of this Master’s Thesis is to study how different water chemistry parameters change as water flows through the lakes in the watershed of the river Emån. Water chemistry data was extracted from the Swedish University of Agricultural Sciences database. By using the ArcGIS toolset STARS, Spatial Tools for the Analysis of River Systems, it was possible to build a landscape network. The water chemistry parameters that were analyzed included: pH, color, absorbance filtered (Abs), acid neutralizing capacity (ANC), inorganic nitrogen (IN), organic nitrogen (ON), total amount nitrogen (TN), total organic carbon (TOC), total phosphorus (Tot-P) and phosphate (PO4-P). In this thesis statistical analysis of available data were performed including processing and quantifying the impact of lakes on water chemistry. While this approach does not inherently consider chemical, physical or biological processes, it does offer a straightforward view of possible patterns of interactions between lakes and watercourses in the landscape. Geostatistical models are important tools for understanding how chemical and biological processes operates in lakes and stream networks. When geostatistical models are analyzed, different distance models can give a deeper insight of what happens between monitoring stations. When determining the routes and the distances between monitoring stations in a network it is most common to use the Euclidean (straight line) distance or the hydrological distances. Further, these distances can be defined either symmetrically or asymmetrically.  Studies have shown that there is a need in how to properly analyze lakes in these distance models. In this thesis the lengths between inlet and outlet of the lakes in the stream network, lake length (SL), were calculated for all the lakes. SL were compared within the distance metrics mentioned above to discern the impacts of lakes. The area lake and wetlands, SV, were also calculated to each site. The analyses were performed with water chemistry data from August for the years 2010 and 2013. Data was collected from all monitoring stations during this month. The difference in average month flow rate was highest in 2010 and 2013 compared to other years.Analyses showed that Abs, color, IN, ON, PO4-P, TN, TOC and Tot-P had a negative correlation in relation to SL and SV. On the other hand, pH had a positive correlation and there were no significant correlations for ANC. SL had a strong correlation with lake area, volume, maximum depth and average depth. Based on these findings it can be concluded that lakes have a stronger impact on changing water chemistry than streams. In a landscape perspective the water chemical parameters increased in concentration as water flowed downstream, but the concentrations decreased as water flowed through the lakes. The results of this study demonstrate that SL supplies an adequate way to describe the path of water through the lakes shown in the correlation between SL and lake properties.

Canals surrounding the Everglades carry enriched and polluted water high in minerals and nutrients. These enriched waters impact adjacent marsh habitats, altering flora and fauna species and abundance. Multiple studies have found gradients in nutrient levels as a function of distance from canals and emphasize the sensitivity of some organisms to these changes in water chemistry. Florida apple snails, Pomacea paludosa Say, are just one of many Everglades species sensitive to changes in water chemistry. They serve as an important staple in the diets of many Everglades predators including turtles, crayfish, limpkins and most importantly the endangered snail kite, Rostrahamus sociabilis which feeds almost exclusively on the apple snail. To examine potential effects of water chemistry on apple snail breeding patterns, we observed snail egg size, egg number per clutch, and carbon and nitrogen contents along water chemistry gradients and among snail breeding months at the Arthur R. Marshall Loxahatchee National Wildlife Refuge. Egg number per clutch and egg diameters were greatest in the most impacted zones and lowest in the pristine, interior zone. Carbon contents of eggs were highest in the interior and east side of the Refuge and lowest in the west side. Nitrogen contents of eggs were highest in the interior and west side of the Refuge, and lowest in the east side. Significant, albeit weak, positive trends were found between N content and egg diameter, C content and egg diameter, and between egg number per clutch and egg diameter, but only among specific zones and months. Results from this study suggest that snails in areas of the Refuge that are influenced by canal-water may produce greater numbers of apple snail offspring with greater egg diameters than those in less impacted areas. However, we do not know if this translates into higher hatchling success and survival.

Climate change is causing larger wildfires and more extreme precipitation events throughout the world. As these ecological disturbances increasingly coincide, they are altering lateral fluxes of sediment, organic matter, and nutrients. Increased lateral flux of nutrients could exacerbate eutrophication and associated harmful algal blooms, and increased sediment and organic matter flux could degrade the water supply. Here, we report the immediate stream chemistry response of watersheds in central Utah (USA) that were affected by a megafire followed by an extreme precipitation event in 2018. The wildfires burned throughout the summer of 2018 until the remnants of Hurricane Rosa released torrential rain on the still smoldering, 610-km2 burn scar. To assess how these multiple stressors affected lateral material fluxes, we collected daily to hourly water samples at 10 stream locations starting immediately before the storm event until three weeks after it finished. We quantified suspended sediment, solute and nutrient concentrations, water isotopes, and the concentration, optical properties, and reactivity of dissolved organic matter. For all land-use types, the wildfire caused substantial increases in sediment concentration and flux, increasing total suspended sediment by over 20-fold, attributable to the loss of stabilizing vegetation and increased runoff. Unexpectedly, dissolved organic carbon (DOC) was 2.1-fold higher in burned watersheds, despite the decrease in plant and soil organic matter, and this DOC was 1.3-fold more biodegradable and 2.0-fold more photodegradable than in unburned watersheds based on 28-day light and dark incubations. However, nitrogen and phosphorus concentrations were higher in watersheds with high anthropogenic influences, regardless of burn status. Likewise, direct human land use had a greater effect than wildfire on runoff response, with rapid storm water signals in urban and agricultural areas and a slow arrival of storm water in unburned areas without direct human influence. These findings indicate how megafires and intense rainfall fundamentally increase short-term sediment flux and alter organic matter concentration and characteristics, confirming previous research. These fluxes of degradable dissolved and particulate organic matter could exert short-term pressure on ecosystems already fragmented by human infrastructure. However, in contrast with previous research, which overwhelming focuses on burned-unburned comparisons in pristine watersheds, we found that the presence of urban and agricultural activity exerted a much greater influence on nutrient status than the wildfire. This novel finding suggests that reducing nutrient fluxes from urban and agricultural areas could make ecosystems more resilient to megafire and extreme precipitation events. Together with reducing anthropogenic climate change to reduce the frequency and extent of large wildfires, improving nutrient management should be a priority in semi-arid regions such as Utah.

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