The river water quality management strategy involves a series of complex inter-disciplinary decisions based on speculated responses of water and sediment quality to changing controls. In the aquatic system a rapid removal of the heavy metals from the water to sediments may occur by settling particles while some of these pollutants can be mobilized by getting accumulated into the biota from the sediments sink. Thus, sediment plays a major role in the determining pollution pattern of aquatic systems. It acts as both carriers and sinks for contaminants, reflecting the history of pollution, and providing a record of catchment inputs into aquatic ecosystems. The Yan Shuei Gang River watershed is one the river watersheds in Kaohsiung City, Taiwan. It is 5-km long, drains a catchment of more than 1,200 ha. Part of the river water is from the domestic drainage areas located in the upper catchment. In Linhai Industrial Parks, there are more than 493 registered industrial factories that discharge their wastewater into the Yan Shuei Gang River. Thus, recent water and sediments quality analysis indicates that the Yan Shuei Gang River is heavily polluted. The major objectives of this study were to (1) perform water quality and sediments sampling and analyses, (2) perform water quality simulation and demonstrates the model application to the Yan Shuei Gang River, (3) assess the water and sediments quality, (4) provide foci for immediate remediation efforts, (5) provide benchmark levels to test outcomes of future remediation efforts, (6) design a novel extraction technique that utilizes a mildly elevated pressure in consecutive cycles with a chelating agent for the sediment slurry. Water quality investigation results show that the biochemical oxygen demand (BOD), ammonia-nitrogen (NH3-N), and suspended solid (SS) average concentrations in water samples of the Salt-water River varied from 10.2 to 194, 8.51 to 18.3, and 7.9 to 19.5 mg/L, respectively. The results of the chemical analysis of the Salt-water River surface sediments showed that the sediments present highly elevated Cd, Cr, Ni, Cu, Pb, Zn and Fe concentrations. Investigation results reveal that sediment samples contained significant amount of iron (up to 3.6%), Cr (up to 66.5 mg/kg), Pb (up to 36.5 mg/kg), Ni (up to 43 mg/kg), and Al (up to 1.8%). All heavy metal concentrations were higher than the world average, sediments average and sediment quality guidelines (SQGs). Although all metals showed varied concentrations, the approaches of factor analysis, normalized enrichment factor (EF), and the geo-accumulation index (Igeo) proposed in this paper were effectively used to differentiate the natural and anthropogenic sources of the metals. Both the EF and Igeo indicated similar anthropogenic contamination degree of the metals. The potential acute toxicity in sediment of Yan Shuei Gang River was observed to be mainly due to Cu contamination. Cu was the major toxicity contributor accounting for 32-46% of the total toxicity in Salt-water River, followed by Zn. The Water Quality Analysis Simulation Program (WASP) model developed by US Environmental Protection Agency (EPA) was selected as a water quality planning tool to perform the water quality evaluation. Modeling results show that the current daily pollutant inputs were much higher than the calculated carrying capacity for nutrients and BOD of the Yan Shuei Gang River. Based on the results from this study, the following remedial strategies have been proposed to minimize the impacts of industry and domestic source pollution on the water quality of Salt-water River: (1) increase the flow by transporting 1 m3/s unpolluted surface water from other sources to dilute the polluted river water, (2) construction of the intercepting systems to effective intercept and transport the untreated wastewater to the wastewater treatment systems. The sediments batch extracted by 150 psi pressure cycles has the most Cu removed rater (70%), much higher than without treatment (55%) or with 90 psi pressure cycles treatment (65%). Pressure-assisted extraction achieves in 60 min the amounts of Cu equal to or exceeding those achieved in 240 min without pressure cycles under the same concentration conditions. This research indicates that the advantages of pressure cycle system are increased process speed, more thorough extraction, and reduced use of the chelating agent. The heightened treatment is explained by sediments aggregate fracturing upon pressure cycles that exposes the contaminants as well as by the chelating agents. The technique is expected to accelerate extraction treatment of a wide range of heavy metal contaminants, and it may provide treatment to dredged and stored contaminated sediments. Experience obtained from this study will be helpful in designing the sediment and river management strategies for other similar river watersheds.

The distribution, enrichment, and accumulation of heavy metals in the sediments, especially those at the vicinity of tributary estuaries of Kaohsiung Harbor, Taiwan were investigated. Sediment samples from six locations in the Kaohsiung Harbor were collected quarterly in the period from 2002 to 2005 and characterized for metal content (e.g., Hg, Pb, Cd, Cr, Cu, Zn and Al), water content, organic matter, total nitrogen, total phosphorous, total grease, and grain size. Results showed that metal concentrations varied from 0.58 mg kg-1 for Cd to 596 mg kg-1 for Zn. Metal concentrations at the vicinity of river mouths were higher than those at other locations. All heavy metals studied, except Cr, had relatively high enrichment factors and geo-accumulation indices in the estuaries. Moreover, metal concentrations correlated closely to the physical-chemical properties of the sediments, which strongly suggested the influence of industrial and municipal wastewaters discharged from the neighboring industrial parks and river basins. Results would help develop strategies for pollution control and sediment remediation of Kaohsiung Harbor. Ocean disposal of wastes such as dredged sediments causes the concentrations of contaminants and some other water quality parameters in the water column to change. In this study, the STFATE (Short-term Fate) system, a model developed by the US Corps of Engineers for managing automatic dredging and disposal of the dredged materials, was used to model and simulate the deposition, dispersion and accumulation of the dredged material disposed at an ocean site. Additionally, aerial photographs taken from a helicopter on dispersion of the disposed sediments were used to calibrate and verify the modeling results for evaluating its applicability in predicting the influence of disposing dredged sediments on the surrounding seawater quality. Simulation results indicate that after 4 h of ocean disposal, the dredged sediment showed negligible adverse influence on the seawater quality (SS = 3 ¡V 4 mg/L). Results of simulating the dispersion of dredged sediments revealed that 20 seconds disposal duration resulted in smaller influence distance and range but a longer time for the seawater to recover to its original state. A longer disposal time of 1,200 seconds would cause a larger distance and range of influence but a shorter recovery time. The verification results demonstrate that simulated values on the dispersion length, width, area and shape generally comfort to the trends of monitored data; the average error is around 27.8%.

Submitted by (lucia.rodrigues@ufrpe.br) on 2016-08-17T12:29:29Z No. of bitstreams: 1 Nielson Machado dos Santos.pdf: 2159134 bytes, checksum: 0924bbce3bea148e3c14b840a9443026 (MD5) / Made available in DSpace on 2016-08-17T12:29:29Z (GMT). No. of bitstreams: 1 Nielson Machado dos Santos.pdf: 2159134 bytes, checksum: 0924bbce3bea148e3c14b840a9443026 (MD5) Previous issue date: 2015-07-06 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This work was carried out to investigate the possible influence of human activities on heavy metal concentrations, by enrichment factor and isotopic signature of Pb and determine the natural levels of heavy metals in the vicinity Todos os Santos Bay-BA (BTS). For this, two sampling design of the soil around the BTS were realized. The first sampling 114 topsoil samples (0.0 - 0.2 m depth) were collected from 38 samplings sites and the concentrations of Pb, Zn, As, Cd, and Hg were determined by ICP-OES or AA-FIAS after microwave sample digestion. Results showed that mean values for heavy metal concentrations in soils (mg kg-1) followed the order Pb (39.45) > Zn (12.52) > As (1.95) > Cd (0.23) > Hg (0.09). The mean natural concentrations of heavy metals found in the soils of an important economic region of Brazil’s were generally lower than those reported in the national and international literature, with exception Pb concentration that was higher than all compared soils.The quality reference values (QRvs) calculated for the TSB based on the 75th percentile, were as follows (mg kg−1): Pb (54.37); Cr (36.55); Zn (10.40); Cu (7.10); Ni (4.05); Co (0.38); Cd (0.30). The second sampling six soil profiles were collected, the samples were collected from different horizons, totaling 44 samples. Soil pits were dug until 2 m or until the parent material (C horizon) was reached.The soil samples were microwave digested in the mixture of HNO3, H2O2 using the method described by Sah and Miller (1992). Concentrations of Pb and the isotopes 204Pb, 206Pb, 207Pb and 208Pb were measured on an inductively coupled plasma (quadrupole) mass spectrometry. Pb concentrations varied from 3.2 to 44.1 mg kg−1 with an average concentration of 13.65 mg kg−1. In general the samples feature a wide range of Pb isotope ratios, ranging from 36.71 to 47.38 for 208Pb/204Pb, 16.86 to 20.59 for 206Pb/204Pb, 1.10 to 1.31 for 206Pb/207Pb and a ranged slightly from 15.00 to 15.65 for 207Pb/204Pb. The PCA performed identified that Pb, Zn, and Cd were associated with the same factor (F1) and had chiefly anthropogenic origin whereas Pb and Zn have also contributions from both sources (natural, lithogenic and anthropogenic). The As and Hg concentrations (F2) were related to the natural component; the parent material underlying the soils (igneous-metamorphic rocks) seemingly confirm this hypothesis. The natural concentrations of heavy metals in soils of TSB had the following decreasing order: Pb > Cr > Zn > Cu > Ni > Co > Cd. Pb concentration in all soil profiles not seem have been influenced by the abandoned lead smelter plant located in the municipality of Santo Amaro da Purificação-BA. The distinct Pb isotopic compositions were clearly related to the different exposure of the sampling sites in relation to atmospheric deposition and geological parent material. / Este trabalho foi realizado para investigar a possível influência das atividades humanas sobre as concentrações de metais pesados, por fator de enriquecimento e assinatura isotópica de Pb e determinar os níveis naturais de metais pesados ​​nas imediações Todos os Santos Bay-BA (BTS). Para isso, duas projecto de amostragem do solo ao redor da BTS foram realizados. A primeira amostragem de 114 amostras de solo superficial (0,0-0,2 m de profundidade) foram coletadas de 38 amostragens sites e as concentrações de Pb, Zn, As, Cd, Hg e foram determinados por ICP-OES ou AA-FIAS após digestão de amostras de microondas. Os resultados mostraram que os valores médios para as concentrações de metais pesados ​​em solos (mg kg-1) seguido a ordem Pb (39,45)> Zn (12,52)> Como (1,95)> Cd (0,23)> Hg (0,09). As concentrações médias naturais de metais pesados ​​encontrados nos solos de uma importante região econômica do Brasil de foram em geral menores que os relatados na literatura nacional e internacional, com exceção Pb concentração que era maior do que todos em comparação soils.The valores de referência de qualidade (QRvs) calculada para TSB a partir do percentil 75, foram as seguintes (mg kg-1): Pb (54,37); Cr (36,55); Zn (10,40); Cu (7,10); Ni (4,05); Co (0,38); Cd (0,30). A segunda amostragem seis perfis de solo foram coletadas, as amostras foram coletadas de horizontes diferentes, totalizando 44 amostras. Poços de solo foram escavadas até 2 m ou até que o material de origem (C horizonte) foi amostras de solo foram reached.The microondas digerido na mistura de HNO3, H2O2, utilizando o método descrito por Sah e Miller (1992). As concentrações de Pb e os isótopos 204Pb, 206Pb, 207Pb e 208Pb foram medidos em uma espectrometria de massa com plasma indutivamente acoplado (quadrupolo). Concentrações de Pb variou de 3.2 para 44,1 mg kg-1 com uma concentração média de 13,65 mg kg-1. Em geral, as amostras apresentam uma vasta gama de relações isotópicas Pb, variando 36,71-47,38 para 208Pb / 204Pb, 16,86-20,59 para 206Pb / 204Pb, 1,10-1,31 para 206Pb / 207Pb e uma variou ligeiramente 15,00-15,65 para 207Pb / 204Pb . O PCA realizada identificou que Pb, Zn e Cd foram associados com o mesmo fator (F1) e teve origem principalmente antropogénica Considerando Pb e Zn também tem contribuições de ambas as fontes (naturais, litogênicos e antropogênicos). As concentrações de Hg e Como (F2) estavam relacionados com a componente natural; o material de origem subjacentes aos solos (ígnea-rochas metamórficas) aparentemente confirmar esta hipótese. As concentrações naturais de metais pesados ​​em solos de TSB teve a seguinte ordem decrescente: Pb> Cr> Zn> Cu> Ni> Co> Cd. Concentração de Pb em todos os perfis de solo não parecem ter sido influenciados pela planta fundição de chumbo abandonada localizada no município de Santo Amaro da Purificação-BA. As composições isotópicas de Pb distintas foram claramente relacionadas com a diferente exposição dos pontos de amostragem em relação à deposição atmosférica e material de origem geológica.

The distribution and potential sources of 15 polycyclic aromatic hydrocarbons (PAHs) in soils and Digitaria eriantha in the vicinity of three South African coal-fired power plants, Matla, Lethabo and Rooiwal were determined by gas chromatography–mass spectrometry. An ultrasonic assisted dispersive liquid-liquid microextraction (UA-DLLME) method was developed for the extraction of polycyclic aromatic hydrocarbon in soil, followed by determination using gas chromatography mass spectrometry. The study showed that an extraction protocol based on acetonitrile as dispersive solvent and C2H2Cl2 as extracting solvent, gave extraction efficiencies comparable to conventional soxhlet extraction for soil samples. The extraction time using ultrasonication and the volume of the extraction solvent was also investigated. Using a certified reference material soil (CRM), the extraction efficiency of UA-DLLME ranged from 64 to 86% in comparison with the Soxhlet result of 73 to 95%. In comparison with the real sample, the CRM result did not show a significant difference at 95% C.I. The UA-DLLME proved to be a convenient, rapid, cost-effective and greener sample preparation approach for the determination of PAHs in soil samples. PAH compound ratios such as phenanthrene/phenanthrene + anthracene (Phen/ Phen + Anth) were used to provide a reliable estimation of emission sources. The total PAH concentration in the soils around three power plants ranged from 9.73 to 61.24 μg g−1, a range above the Agency for Toxic Substances and Disease Registry levels of 1.0 μg g−1 for a significantly contaminated site. Calculated values of the Phen/Phen + Anth ratio were 0.48±0.08, 0.44±0.05, and 0.38+0.04 for Matla, Lethabo and Rooiwal, respectively. The flouranthene/fluoranthene + pyrene (Flan/ Flan + Pyr) levels were found to be 0.49±0.03 for Matla, 0.44±0.05 for Lethabo, and 0.53±0.08 for Rooiwal. Such values indicate a xx pyrolytic source of PAHs. Higher molecular weight PAHs (five to six rings) were predominant, suggesting coal combustion sources. The carcinogenic potency B[a]P equivalent concentration (B[a] Peq) at the three power plants ranged from 3.61 to 25.25, indicating a high carcinogenic burden. The highest (B[a] Peq) was found in samples collected around Matla power station. It can, therefore, be concluded that the soils were contaminated with PAHs originating from coal-fired power stations. Nine metals (Fe, Cu, Mn, Ni, Cd, Pb, Hg, Cr and Zn) were analysed in soil and the Digitaria eriantha plant around three coal power plants (Matla, Lethabo and Rooiwal), using ICP-OES and GFAAS. The total metal concentration in soil ranged from 0.05 ± 0.02 to 1835.70 ± 70 μg g-1, 0.08 ± 0.05 to 1743.90 ± 29 μg g-1 and 0.07 ± 0.04 to 1735.20 ± 91 μg g-1 at Matla, Lethabo and Rooiwal respectively. The total metal concentration in the plant (Digitaria eriantha) ranged from 0.005 ± 0.003 to 534.87 ± 43 μg g-1 at Matla, 0.002 ± 0.001 to 400.49 ± 269 μg g-1 at Lethabo and 0.002 ± 0.001 to 426.91 ± 201 μg g-1 at Rooiwal. The accumulation factor (A) of less than 1 (i.e. 0.003 to 0.37) at power plants indicates a low transfer of metal from soil to plant (excluder). The enrichment factor values obtained (2.4 – 5) indicate that the soils are moderately enriched, with the exception of Pb that had significant enrichment of 20. The Geo-accumulation Index values of metals indicate that the soils are moderately polluted (0.005 – 0.65), except for Pb that showed moderate to strong pollution (1.74 – 2.53). / Chemistry / D. Phil. (Chemistry)

The distribution and potential sources of 15 polycyclic aromatic hydrocarbons (PAHs) in soils and Digitaria eriantha in the vicinity of three South African coal-fired power plants, Matla, Lethabo and Rooiwal were determined by gas chromatography–mass spectrometry. An ultrasonic assisted dispersive liquid-liquid microextraction (UA-DLLME) method was developed for the extraction of polycyclic aromatic hydrocarbon in soil, followed by determination using gas chromatography mass spectrometry. The study showed that an extraction protocol based on acetonitrile as dispersive solvent and C2H2Cl2 as extracting solvent, gave extraction efficiencies comparable to conventional soxhlet extraction for soil samples. The extraction time using ultrasonication and the volume of the extraction solvent was also investigated. Using a certified reference material soil (CRM), the extraction efficiency of UA-DLLME ranged from 64 to 86% in comparison with the Soxhlet result of 73 to 95%. In comparison with the real sample, the CRM result did not show a significant difference at 95% C.I. The UA-DLLME proved to be a convenient, rapid, cost-effective and greener sample preparation approach for the determination of PAHs in soil samples. PAH compound ratios such as phenanthrene/phenanthrene + anthracene (Phen/ Phen + Anth) were used to provide a reliable estimation of emission sources. The total PAH concentration in the soils around three power plants ranged from 9.73 to 61.24 μg g−1, a range above the Agency for Toxic Substances and Disease Registry levels of 1.0 μg g−1 for a significantly contaminated site. Calculated values of the Phen/Phen + Anth ratio were 0.48±0.08, 0.44±0.05, and 0.38+0.04 for Matla, Lethabo and Rooiwal, respectively. The flouranthene/fluoranthene + pyrene (Flan/ Flan + Pyr) levels were found to be 0.49±0.03 for Matla, 0.44±0.05 for Lethabo, and 0.53±0.08 for Rooiwal. Such values indicate a xx pyrolytic source of PAHs. Higher molecular weight PAHs (five to six rings) were predominant, suggesting coal combustion sources. The carcinogenic potency B[a]P equivalent concentration (B[a] Peq) at the three power plants ranged from 3.61 to 25.25, indicating a high carcinogenic burden. The highest (B[a] Peq) was found in samples collected around Matla power station. It can, therefore, be concluded that the soils were contaminated with PAHs originating from coal-fired power stations. Nine metals (Fe, Cu, Mn, Ni, Cd, Pb, Hg, Cr and Zn) were analysed in soil and the Digitaria eriantha plant around three coal power plants (Matla, Lethabo and Rooiwal), using ICP-OES and GFAAS. The total metal concentration in soil ranged from 0.05 ± 0.02 to 1835.70 ± 70 μg g-1, 0.08 ± 0.05 to 1743.90 ± 29 μg g-1 and 0.07 ± 0.04 to 1735.20 ± 91 μg g-1 at Matla, Lethabo and Rooiwal respectively. The total metal concentration in the plant (Digitaria eriantha) ranged from 0.005 ± 0.003 to 534.87 ± 43 μg g-1 at Matla, 0.002 ± 0.001 to 400.49 ± 269 μg g-1 at Lethabo and 0.002 ± 0.001 to 426.91 ± 201 μg g-1 at Rooiwal. The accumulation factor (A) of less than 1 (i.e. 0.003 to 0.37) at power plants indicates a low transfer of metal from soil to plant (excluder). The enrichment factor values obtained (2.4 – 5) indicate that the soils are moderately enriched, with the exception of Pb that had significant enrichment of 20. The Geo-accumulation Index values of metals indicate that the soils are moderately polluted (0.005 – 0.65), except for Pb that showed moderate to strong pollution (1.74 – 2.53). / Chemistry / D. Phil. (Chemistry)