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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.
111

Study on Distribution and Behavior of PFOS (Perfluorooctane Sulfonate) and PFOA (Perfluorooctanoate) in Water Environment / 水環境におけるPFOS(ペルフルオロオクタンスルホン酸)およびPFOA(ペルフルオロオクタン酸)の分布と挙動に関する研究 / ミズ カンキョウ ニ オケル PFOS ( ペルフルオロオクタン スルホンサン ) オヨビ PFOA ( ペルフルオロオクタンサン ) ノ ブンプ ト キョドウ ニ カンスル ケンキュウ

Lien, Nguyen Pham Hong 25 September 2007 (has links)
学位授与大学:京都大学 ; 取得学位: 博士(工学) ; 学位授与年月日: 2007-09-25 ; 学位の種類: 新制・課程博士 ; 学位記番号: 工博第2850号 ; 請求記号: 新制/工/1419 ; 整理番号: 25535 / Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(工学) / 甲第13379号 / 工博第2850号 / 新制||工||1419(附属図書館) / 25535 / UT51-2007-Q780 / 京都大学大学院工学研究科都市環境工学専攻 / (主査)教授 田中 宏明, 教授 藤井 滋穂, 教授 伊藤 禎彦 / 学位規則第4条第1項該当
112

Toxicology and molecular epidemiology of microbes detected in surface water in the Western Cape: The Impact of Informal Settlement

Maboza, Ernest J.M. January 2013 (has links)
>Magister Scientiae - MSc / Informal settlements are often implicated in surface water pollution with faecal matter. In most instances faecal pollution in the associated surface waters persists despite improvements in sewage removal infrastructure. This study evaluates the importance of investigating the water quality of the Plankenbrug River before it reaches Khayamnandi settlement by comparing water quality in spring and in winter upstream (Pre-Khayamnandi) and downstream (Post- Khayamnandi) from the settlement. In this study, faecal indicator bacteria (Escherichia coli and total coliforms) were enumerated using Chromocult agar. E. coli was further characterized with analytical profiling index (API) and haemolysis assays. Both Pre- and Post-Khayamnandi were not significantly different from each other for both total coliforms and E. coli in winter. Pre-Khayamnandi had between 105 and 108 cfu/100 ml for total coliforms while Post-Khayamnandi had total coliform colony count between 106 and 107 cfu/100 ml. E. coli also exhibited a similar pattern with slightly higher counts at Post-Khayamnandi with colony counts from 104 to 107 and 105 to 107 cfu/100 ml. Spring microbial count demonstrated a significant difference to winter counts within each test site (p ≤ 0.01) and across the two sites (p ≤ 0.05). Both total coliforms and E. coli were 102 fold higher at Post-Khayamnandi than at Pre-Khayamnandi in spring. The API assay demonstrated significant difference (p ≤ 0.05) between the two test sites. Pre- Khayamnandi predominantly had two different profiles while Post-Khayamnandi had three. These profiles represented five distinct E. coli biotypes. Sorbitol and sucrose tests within the API assay demonstrated significant differences (p ≤ 0.05) between the two test sites. The prevalence of sorbitol fermenters at Pre-Khayamnandi was 100% while at Post-Khayamnandi it was 73%. Pre-Khayamnandi also demonstrated a significantly higher prevalence of sucrose fermenters than Post-Khayamnandi at 100% and 59% respectively. These differences indicated dissimilar sources of faecal contamination around these sites. Differences in the distributions of sorbitol and sucrose fermenting biotypes demonstrate different toxicity potentials across these two test sites. The haemolysis assay demonstrated that 9% of isolates were haemolytic with reference to both known α- and β-haemolyitic streptococci at Post-Khayamnandi. At Pre-Khayamnandi there was a higher percentage of α- and β-haemolyitic species, 29% and 28%, respectively. Post- Khayamnandi and Pre-Khayamnandi were significantly different from each other with reference to both α- and β-haemolysis (p ≤ 0.05). These haemolytic activities also demonstrate different toxicity potentials across the two sites. In conclusion Khayamnandi contributes to an already heavy faecal load in the Plankenbrug River. Thus remedial measures to maintain high surface water quality of Plankenbrug River should be directed upstream from the Khayamnandi settlement as well as within the settlement equally. This study recommends integration of microbial loads with programs such as the National Microbial Monitoring Program of South Africa to drive prioritization process in directing reclaiming of water quality, inter alia.
113

Hodnocení vlivu krajinné struktury na znečištění povrchových vod v CHKO Křivoklátsko s využitím ArcSWAT / Impact assessment of landscape structure on surface water pollution in Krivoklatsko protected area using ArcSWAT

Hanzlová, Markéta January 2018 (has links)
The topic of thesis deals with a hydrological model SWAT used for impact assessment of landscape structure on surface water pollution in Krivoklatsko protected area. For this purpose using ArcSWAT in the ArcGIS environment there were built hydrological models of three watersheds of various landscape structure located in the area of interest. The measured data of nitrate were used for these models. Concentration of nitrates in the surface waters were simulated by using these models in the period from 2003 until mid-2014. The statistical evaluation of the models including actual landscape structure did not show satisfactory match of the simulated values with the measured values. Due to the uncertainties of the model, including insufficient quantity of measured nitrates, it was not possible to expect exact results. After validation of basic models, it was important to create new models that would include various scenarios of landscape structure organization. New versions represented changes in the use of land classified as arable land in pasture or mixed forests, in the area around the stream to 250 m and 500 m. Modelling of the impact of individual scenarios on the structure of the landscape structure on nitrate concentrations there was displayed a positive effect of grassing and afforestation of...
114

A salinidade das águas superficiais e sua interferência nas condições sócio-econômicas na sub-bacia do rio Cabaceiras - Curimataú paraibano / A salinity of surface water and its interference in socio-economic conditions in sub-basin river Cabaceiras - Curimataú paraibana

Assis, Edvania Gomes de 21 August 2002 (has links)
Made available in DSpace on 2015-05-07T14:49:19Z (GMT). No. of bitstreams: 1 parte2.pdf: 2851369 bytes, checksum: 7d81168f19872afa8d8f8bf527ba97df (MD5) Previous issue date: 2002-08-21 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The semi-arid region of the north-east Brazil, is characterized by drought, with low rainfall indices, high evaporation, high incoming solar radiation, and soils susceptible to salinization. In this scenario, populations seek the areas close to the ponds (locally known as açudes ), aiming to achieve satisfactory life condition and development. Ponds are found practically everywhere in the sertão . The ponds accumulate water during the rainy period, but not for a long time, because of periodic droughts and high evaporation. In the sub-basin of River Caraibeiras, in the municipality of Barra de Santa Rosa, there are two noteworthy ponds: Poleiro and Curimataú, both planned for water supply. It was aimed in the present study to estimate the water salinity indices of those ponds and how they affect socio-economic conditions in that region. Results obtained from the water physical-chemical analyses showed a high salt concentration, in the ponds, limiting the water consumption by humans, animals and crop irrigation. Such situation alters the habits of human communities and affects directly the socioeconomic condition in that region / O Semi-Árido do Nordeste brasileiro é caracterizado pela carência hídrica, baixos índices pluviométricos, alta evaporação e insolação e solos tendentes à salinização. É neste cenário que as populações procuram as áreas próximas aos açudes, com o objetivo de manter uma condição de vida satisfatória ao seu desenvolvimento. A presença de açudes ocorre em praticamente todo o sertão. Estes acumulam água no período chuvoso, não permanecendo assim por muito tempo, devido à ocorrência de secas periódicas e alta evaporação. Na Sub-bacia do Rio Caraibeiras, no município de Barra de Santa Rosa, dois açudes se destacam: o Poleiro e o Curimataú, com fins de abastecimento público. O presente estudo tem como objetivo avaliar o índice de salinidade das águas desses reservatórios e sua influência nas condições sócioeconômicas da região. Os resultados obtidos através de análises físico-químicas da água, registraram uma grande concentração de sais nas águas dos açudes, restringindo o uso para o consumo humano, dessedentação dos animais e na irrigação. Esta situação modifica os hábitos das comunidades e interfere diretamente nas condições socioeconômicas da região
115

Srážkově - odtokové parametry vybraných povodí Stropnice / Rainfall - runoff parameters selected basin Stropnice

FRAŇKOVÁ, Diana January 2010 (has links)
Dissertation work rainfall-drainage parameters on chosen river-basin Stropnice is dealing with measurement of drainage value of surface water on five specific profiles in the area of Horní Stropnice. The goal was discovery and analysis of information on the river-basin Bedřichovský, Pasecký and Váckový stream, Humenická dam and in closure profile at Tomkův mill in the years 2007 {--} 2010, where there were monitoring heights of water level. After substitution into discharge-rating curve were scoring flow rate for individual parts of river-basins and examination of influence Humenická dam on flow rate wave in the closure profile. Between the upper specific profiles of individual streams above Humenická dam and specific profile by the Tomkův mill there was not found any influence of Humenická dam on flow wave in the river basin of Stropnice.
116

Monitoramento de agrotóxicos em áreas irrigadas por pivô central na microbacia do Tijunqueiro, município de Morrinhos, Goiás / Pesticides monitoring in irrigated areas by central pivot in the Tijunqueiro Watershed municipality of Morrinhos, Goias

Aderbal Almeida Rocha 12 August 2011 (has links)
A importância dos agrotóxicos para o sistema de produção agrícola é indiscutível, uma vez que constituem parte dos insumos básicos. No entanto, é fundamental que sejam adequadamente utilizados para a preservação da qualidade não só do produto cultivado, mas também dos próprios recursos naturais, especialmente o solo e a água. Neste estudo, foi realizado o monitoramento dos agrotóxicos utilizados em lavouras irrigadas por pivô central, na microbacia do Tijunqueiro, município de Morrinhos, estado de Goiás, que apresentaram potencial de contaminação ambiental (critérios da Agência de Proteção Ambiental dos Estados Unidos EPA, índice GUS Groundwater Ubiquity Score, método GOSS e do Instituto Brasileiro de Recursos Naturais Renováveis e não Renováveis IBAMA) e sensíveis ao espectrômetro de massas (LC-MS/MS Cromatografia líquida acoplada ao espectrômetro de massas), no período entre fevereiro de 2009 e setembro de 2010, em amostras de águas superficial e subsuperficial, peixes e sedimentos. Os ingredientes ativos (agrotóxicos) monitorados foram: acefato, atrazina, azoxistrobina, buprofezina, carbofurano, ciproconazole, clorpirifós, difeconazole, diurom, imidacloprido, malationa, metamidofós, metolacloro, metribuzim, monocrotofós, monuron, tiametoxam e triazofós. Amostras de água superficial foram coletadas a montante e a jusante da represa do Tijunqueiro; água subsuperficial em poços piezométricos perfurados no entorno da área irrigada; peixes e sedimentos foram coletados na represa do Tijunqueiro. A técnica de extração em fase sólida (SPE) foi utilizada para extrair os ingredientes ativos das amostras de água, dispersão da matriz na fase sólida (DMFS) para as amostras de sedimentos e QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) para as amostras de peixes. Os métodos multiresíduos utilizados foram adequados e eficientes para a análise e quantificação por LC-MS/MS. Verificou-se que todas as curvas analíticas apresentaram coeficiente de correlação superior a 0,99 e as recuperações foram satisfatórias (70 % a 120 % de recuperação) para a maioria dos ingredientes ativos monitorados. Nas amostras de água superficial, peixe e sedimentos, não foram detectados resíduos dos ingredientes ativos monitorados e 25,7 % das amostras de água subsuperficiais apresentaram contaminação por atrazina / The importance of pesticides to the agricultural system production is indisputable, since they are part of the basics inputs, however, it is essential that they be used properly to be preserved not only the quality of the growing product, but also of their own natural resources, especially soil and water. In this study was conducted the pesticides monitoring used on crops irrigated with a central pivot in the Tijunqueiro watershed municipality of Morrinhos, state of Goias, who had potential for environmental contamination (criteria of the Environmental Protection Agency from the United States EPA, index of GUS - Groundwater Ubiquity Score, GOSS method and Brazilian Institute of Environment and Renewable Natural Resources IBAMA) and sensitive to the mass spectrometer (LC-MS/MS Liquid Chromatography coupled to mass spectrometer) on the period between February 2009 and September 2010, in samples of surface and groundwater, fish and sediment. The active ingredients (pesticides) monitored were acephate, atrazine, azoxistrobin, buprofezin, carbofuran, cyproconazol, chlorpyriphos, difenoconazol, diuron, imidacloprid, malathion, metamidophos, metolachlor, metribuzin, monocrotophos, monuron, thiamethoxan and triazophos. Surface water samples were collected upstream and downstream of the Tijunqueiro dam; groundwater in piezometric wells drilled around the irrigated area; fishes and sediments were collected in the Tijunqueiro dam, The solid phase extraction technique (SPE) was used to extract the analytes from water samples, dispersive solid phase extraction (dSPE) for the sediments samples and QuEChERS (Quick, Easy, Cheap, Effective, Rugged) for the fishes samples. Multiresidue methods used in the study were adequate and efficient for the analysis and quantifications by LC-MS/MS. Was found that all the analytical curves showed correlation coefficients greater than 0,99 and the recoveries were satisfactory (70 % a 120 % of recovery) for most of the active ingredients studied. In the surface water samples, sediments and fish were not detected residues of the active ingredients monitored and 25.7 % groundwater samples showed atrazine contamination
117

Investigação de agrotóxicos carbamatos em águas superficiais bruta e tratada no Rio Branco em Roraima

Leonidas de Holanda Farias Filho 29 August 2013 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Os agrotóxicos vêm sendo amplamente utilizados no combate a inúmeros grupos de insetos, vegetais, fungos e demais seres vivos que diminuem o rendimento agrícola em cultivos variados, também podem ser manipulados contra vetores de enfermidades para seres humanos e outros animais. Em muitos casos, o seu uso indiscriminado, causa problemas ambientais aparentemente imperceptíveis, mas de grande magnitude na biota impactada. Sendo alguns grupos de agrotóxicos, utilizados em pequenas doses, causam a morte e podem acumular-se nos tecidos animais e vegetais, sua decomposição pode ser muito lenta possibilitando alcançarem regiões distantes de onde foram utilizados. São transportados pelas águas subterrâneas e superficiais, e em algumas ocasiões, dispersados pelos ventos atmosféricos. Sua detecção e quantificação se dá por técnicas e equipamentos de elevada sensibilidade, pois sua distribuição no meio ambiente, na maioria das vezes, está em pequenas concentrações. Neste trabalho foram coletadas águas superficiais do rio Branco e na Estação de Tratamento da cidade de Boa Vista e em seguida submetido à técnica de extração Líquido-Sólido, SPE- off-line, para pré-concentração dos pesticidas e depois a Cromatografia Líquida de Alta Eficiência - CLAE para a sua separação e quantificação. Foram detectados os agrotóxicos carbamatos: aldicarbe sulfona, carbofurano, carbaril, hidroxi carbofurano, metomil e nafitol com suas concentrações sempre acima do recomendado pela Portaria 2.914/11 MS e Resolução CONAMA 357/05. A água tratada distribuída a população apresentou traços de três tipos de carbamatos acima do permitido pela legislação brasileira, Aldicarbe sulfona 9,10 mg L-1, Carbaril 1,0 mg L-1 e metomil 32 mg L-1. Foram feitos testes de recuperação dos analitos carbaril e metomil, na qual apresentaram resultados de 85 e 105 % respectivamente, para o método utilizado, demonstrado que o procedimento é confiável. Os resultados apresentados aumentam a preocupação em torno dos impactos que os agrotóxicos podem causar ao meio ambiente e a saúde das pessoas que utilizam as águas do rio Branco diariamente. / Pesticides have been widely used to combat numerous groups of insects, plants, fungi and other living beings that reduce crop yield in various crops, can also be manipulated against disease vectors to humans and other animals. In many cases, their indiscriminate use, causes environmental problems seemingly imperceptible, but of great magnitude in biota impacted. As some groups of pesticides used in small doses, can cause death and accumulate in animal and plant tissues, their decay can be very slow allowing reach distant regions from which they were used. Are transported by groundwater and surface water, and on some occasions, dispersed by atmospheric winds. Its detection and quantification is done by standard techniques and equipment with high sensitivity since its distribution in the environment, in most cases, is in small concentrations. In this work we collected surface water of the Branco river and Treatment Station of the city of Boa Vista and then subjected to extraction technique Liquid - Solid -off -line SPE for pre-concentration of pesticides and then the High Performance Liquid Chromatography efficiency - HPLC for their separation and quantification. Pesticides were detected carbamates aldicarb sulfone, carbofuran, carbaryl, hydroxicarbofuran, methomyl and naphytol always with their concentrations above recommended by Ordinance 2.914/11 MS and CONAMA Resolution 357 / 05. The treated water distributed population showed traces of three types of carbamates above those permitted by Brazilian law, Aldicarb sulfone 9.10 mg L-1, Carbaryl 1.0 mg L-1 and methomyl 32 mg L-1. Tests were made to recover the analytes carbaryl and methomyl, which showed results of 85 and 105 %, respectively, for the method used, demonstrated that the procedure is reliable. The results presented raise concern about the impact that pesticides can cause to the environment and health of people who use the waters of the Branco river daily.
118

Study on Contamination of Perfluorinated Compounds (PFCs) in Water Environment and Industrial Wastewater in Thailand / タイにおける水環境および工業廃水のペルフルオロ化合物(PFCs)汚染に関する研究 / タイ ニ オケル ミズ カンキョウ オヨビ コウギョウ ハイスイ ノ ペルフルオロ カゴウブツ ( PFCs ) オセン ニ カンスル ケンキュウ

Kunacheva, Chinagarn 24 September 2009 (has links)
PFCs are used in a wide variety of industrial and commercial applications for more than 50 years. Among variation of PFCs, Perfluorooctane sulfonate (PFOS) (CF3(CF2)7SO3-) and perfluorooctanoic acid (PFOA) (CF3(CF2)6COO-) are the most dominant PFCs. In May 2009, PFOS, its salts and perfluorooctane sulfonyl fluoride (PFOSF) are designated as new Persistent Organic Compounds (POPs) which are resistant, bio-accumulating, and having potential of causing adverse effects to humans and environment (IISD, 2009). However, products containing PFCs are still being manufactured and used, which could be the main reason why they are still observed in the environment and biota (Berger et al., 2004; Saito et al., 2003; Sinclair et al., 2004). The study is focused on the PFCs contamination in water and industrial wastewater around the Central and Eastern Thailand, where is one of the major industrialized areas in the country. The samplings were conducted in major rivers, Chao Phraya, Bangpakong and Tachin River. PFCs were contaminated in all rivers. The average total PFCs were 15.10 ng/L, 18.29 ng/L and 7.40 ng/L in Chao Phraya, Bangpakong and Tachin River, respectively. PFOS and PFOA were the predominant PFCs in all samples. The total of 118.6 g/d PFOS and 323.6 g/d PFOA were released from the three rivers to the Gulf of Thailand. The survey was also conducted in small rivers, reservoirs, and coastal water around Eastern Thailand, where many industrial zones (IZ) are located. The geometric mean (GM) concentration of each PFC was ranged from 2.3 to 107.7 ng/L in small rivers, 2.2 to 212.2 ng/L in reservoirs, and 0.8 to 41.1 ng/L in coastal water samples. The higher PFCs contaminations were detected in the surface water around the industrial zones, where might be the sources of these compounds. Field surveys were also conducted in ten industrial zones (IZ1 – IZ10) to identify the occurrences of PFCs from in industries. The recovery rates of PFCs in the samples indicated that the matrix interference or enhancement was an important problem in PFCs analysis. The elevated concentrations were detected in electronics, textile, chemicals and glass making industries. Total PFCs concentrations in the influent of WWTP were ranged from 39.6 to 3, 344.1 ng/L. Ten industrial zones released 188.41 g/d of PFCs. All of the treatment processes inside industrial zones were biological processes, which were reported that they were not effective to remove PFCs. The influence of industrial discharges was affected not only the rivers and reservoirs but also in the coastal water. The PFCs in rivers and reservoirs were discharged to the Gulf of Thailand, which is the important food source for Thai people and exports. Due to the problems in industrial wastewater analysis, several optimizing options were applied in PFCs analytical method especially in Solid Phase Extraction (SPE) procedure. The combination of PresepC-Agri and Oasis®HLB was the better option for analyzing PFCs in water samples. The optimum flow rate for loading the samples was 5 mL/min. Methanol (2 mL) plus Acetronitrile (2 mL) was the effective way to elute PFCs from the cartridges. The specific solvent percentages to elute each PFCs were identified for both water and industrial wastewater samples. The matrix removal methods by using Envi-Carb and Ultrafilter were effective for different types of industrial wastewater samples. PFCs were detected in surface waters, which are the sources of tap and drinking water for the people in Central and Eastern Thailand. The surveys were conducted in Bangkok city. Samples were collected from water treatment plants (WTPs), tap water, and drinking water. PFCs were detected in all tap water and drinking water samples. PFOS and PFOA concentrations in raw water of WTP were found 4.29 ng/L and 16.54 ng/L, respectively. The average PFOS and PFOA concentrations in tap water were detected 0.17 and 3.58 ng/L, respectively. The tap water results also showed that PFOS and PFOA concentrations were not similarly detected in all area in the city. PFOA were detected higher in the western area, while PFOS concentration was quite similar in all areas. Overall, it can be concluded that the current treatment processes were not completely remove PFCs. Nevertheless, PFCs in particulate phase were effectively removed by the primary sedimentation and rapid sand filtration. Elevated PFCs were found in the industrial zones (IZ2 and IZ5). To understand the distribution and fate of PFCs during industrial wastewater process, PFCs mass flows were studied. Higher PFCs in adsorbed phase were detected only in activated sludge and some influent samples. In IZ2, PFOA loading in the dissolved phase increased after activated sludge process by 5%. There was no degradation of PFOA inside the polishing pond. The highest loading to the treatment plant was PFOS with the loading of 2, 382 mg/d and 1, 529 mg/d in dissolved and adsorbed phase, respectively. Unlike PFCAs that showed no removal in the treatment process, PFOS were decreased during the treatment processes with 36% in the activated sludge process and 36% in the polishing pond. The predominant in this IZ5 was PFOS. The increasing of PFOS was also found in this treatment plant dissimilar to IZ2. PFOS was increasing by 45% in dissolved phase and 47% in adsorbed phase. All of PFCs in this industrial zone were detected higher in the effluent, indicated that PFCs’ precursors should be the major effects of this contamination. / Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(工学) / 甲第14930号 / 工博第3157号 / 新制||工||1473(附属図書館) / 27368 / UT51-2009-M844 / 京都大学大学院工学研究科都市環境工学専攻 / (主査)教授 田中 宏明, 教授 清水 芳久, 教授 藤井 滋穂 / 学位規則第4条第1項該当
119

Risk assessment: to surface water in Kallerstadsdiket and Stångån near the closed Kallerstad landfill, Linköping.

Karpestam, Einat January 2017 (has links)
Kallerstaddeponin användes aktivt för deponering av avfall mellan 1950 och 1973. Nedlagda deponier bör dock bedömas med avseende på den risk de utgör för miljö och hälsa. I denna studie, jämfördes nivåerna av zink, nickel, arsenik, koppar, ammoniak, TOT-N och TOC i deponins huvudrecipient, Kallerstadsdiket, med de gränsvärden som fastställts av Havs- och vattenmyndigheten. Därefter uppskattades Kallerstaddeponins direkta bidrag till föroreningsnivån. Slutligen, beräknades spridningsrisken, nämligen den föroreningsbelastning som flödar från Kallerstadsdiket till Stångån, som är en andra recipient. Zink, nickel och koppar visade låga nivåer och låg risk på alla provtagningsstationer. Ammoniak och arsenik visade högre nivåer och en potentiell risk för negativa effekter. Detta innebär att Kallerstadsdikets ytvatten inte klassificeras att uppnå "bra" status, även om den direkta rollen som Kallerstaddeponin spelar är tveksam i detta fall. Beräkningarna tyder på att Kallerstaddeponin tillför arsenik och TOC till föroreningsnivåerna, även om det är i små mängder. Risken för spridning av föroreningar till Stångån uppskattades vara låg. Utspädningsfaktorn uppskattades till att vara 1:320 och de ytterligare föroreningsnivåerna som härstammar från Kallerstadsdiket är låga i förhållande till de uppmätta nivåerna i Stångån. Den aktuella studien har många osäkerheter som huvudsakligen är relaterade till tillgängligheten av data. Det rekommenderas därför att tillämpa en mer fullständig provtagning med lämpliga parametrar (t.ex. pH, DOC, Ca och temperatur) i alla provtagningsstationer. Helst skulle det vara önskvärt med provtagning varje vecka under en period av ett år och sedan åter bedöma risken för att få en mer tillförlitlig uppskattning av deponins bidrag. / Kallerstad landfill was in use between 1950 and 1973. Nonetheless, assessment of closed landfills and their risk to the environment and health is required. Firstly, the levels of zinc, nickel, arsenic, copper, ammonia, TOT-N and TOC in the surface water of the main recipient Kallerstadsdiket, were compared to cut-off levels given by the Swedish Agency for Marine and Water Management. Then, the direct contribution of Kallerstad landfill to the contamination level was estimated. Finally, the contamination load that flows from Kallerstadsdiket to Stångån, which is a second recipient with high natural value, was estimated. Zinc, nickel and copper showed low levels and low risk at all sampling stations. Ammonia and arsenic showed higher levels and a potential risk of adverse effects. As a result, the surface water in Kallerstadsdiket could not be classified to reach ‘good’ status, although the direct role that Kallerstad landfill plays is doubtful. Calculations suggest that Kallerstad landfill does add arsenic and TOC to the contamination levels, although in small amounts. The risk of spread of contaminants to Stångån was estimated to be low. The additional contamination levels stemming from Kallerstadsdiket are lower than the levels measured in Stångån. The dilution factor was estimated to be 1:320. Nevertheless, the current study has many uncertainties that are mainly related to data availability. It is therefore recommended to apply a more complete sampling scheme with the appropriate parameters (e.g., pH, DOC, Ca, and temperature) in all sampling stations. Ideally it would be plausible to sample every week for a period of a year and then reassess the risk, as well as to get a more reliable approximation of the contribution of the landfill itself.
120

A conceptual understanding of groundwater recharge processes and surface-water/ groundwater interactions in the Kruger National Park

Petersen, Robin Marc January 2012 (has links)
>Magister Scientiae - MSc / In the Kruger National Park (KNP) which is the flagship conservation area in South Africa, the impact on groundwater should be kept to a minimum as groundwater plays a vital role in sustaining ecosystem functioning and sustaining baseflow to streams and rivers. For this reason groundwater has been recognized as one of the environmental indicators that need to be monitored. The KNP has adopted a Strategic Adaptive Management (SAM) approach with clear ecosystem management goals. The achievement of these goals is evaluated by using environmental indicators. These indicators are evaluated against thresholds of potential concern (TPC). TPCs are a set of boundaries that together define the spatiotemporal conditions for which the KNP ecosystem is managed. TPCs are essentially upper and lower limits along a continuum of change in selected environmental indicators. Historically, groundwater recharge and surface water interaction with rivers has tended to be overlooked in the KNP. This study proposes a conceptual model of groundwater recharge processes in the KNP, defining when and how groundwater recharge occurs. Two methods were used, the Cumulative Rainfall Departure (CRD) and stable isotopes of ²H and ¹⁸O. An adapted version of the CRD which incorporates a long and short term memory of the system was used to identify possible recharge processes. Further, using the CRD method a reliable reconstruction of the long term groundwater level trends are simulated using monthly rainfall totals with reference to the average rainfall over the entire time series 1936-2009. The stable isotope of ²H and ¹⁸O samples from cumulative rainfall samplers, surfacewater (streams and rivers) and groundwater from boreholes were collected monthly for approximately one year (May 2010 to July 2011). The isotope composition of the groundwater was used to establish whether recharge was immediate or delayed. Additionally, the isotopic composition of surface-water from rivers and streams were compared to that of groundwater to identify surface-water interactions. Groundwater recharge in KNP occurs during the rainy summer months (December to March) and very little to none during the dry winter season (April to September). Recharge takes place during rainfall sequences 100mm or more. The stable isotope records collected from cumulative rainfall, groundwater and surface water (streams and rivers) indicate that groundwater experiences evaporation prior to infiltration. As the KNP experiences high evaporation rates, insignificant rainfall sequences contribute little or zero to recharge. The CRD analysis of groundwater level fluctuations shows that recharge to the aquifers respond to dry and wet cycles that last for 6 to 14 years. The KNP experienced several periods of below-average rainfall and hence no significant recharge took place to the basement aquifers. During a normal rainy season the water levels rise somewhat then starts receding again. It is only during major rainfall events that may occur every 100yrs to 200yrs causing the aquifers to fully recharge. This was perfectly illustrated by the high groundwater levels after the 2000 major rainfall event that recharged the aquifers fully. During below average rainfall years the overall water level trend is drastically declining. The system experiences higher natural losses than gains due to outflow of groundwater to streams and rivers. The KNP is divided down the center by two geological formations, granites along the west and basalts along the east. The combination of the CRD model and the stable isotopic analysis suggest that the dominant recharge processes that occur in the southern region of the KNP are direct recharge via piston flow and indirect recharge via preferred pathways particularly streams and rivers. Along the eastern half of the KNP on the Basalts and Rhyolite direct recharge via piston flow are dominant. Groundwater is not recharged via small streams and rivers (Sweni and Mnondozi Rivers) as it was found that at these particular sites these rivers are detached and do not interact with groundwater. Along the western granitic areas the dominant recharge process are indirect recharge. Recharge takes place via preferred pathways particularly streams and rivers. It was found that ephemeral rivers (Nwatsisonto River) act as sinks for groundwater recharge and influent-effluent conditions are experienced along seasonal rivers (Mbyamiti River). The large perennial Sabie and its tributary the Sand River are consistently fed by groundwater, above all maintaining base flow during the dry season. These rivers act as basin sinks receiving groundwater discharge all year round. Using the stable isotope composition of rainfall, surface-water and groundwater to act as a natural tracer, in combination with the CRD method proved invaluable to confirm the plausible recharge processes. The study provided a conceptual understanding of the groundwater system in the KNP forming the foundation to developing acceptable limits (TPCs) of the groundwater levels in the KNP. The model will serve as a guide for the recharge processes and for deciding on the location and time frames for data collection to ultimately set TPCs for groundwater in the KNP to sustainably manage the resource.

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