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Relationships between water quality, species composition, biodiversity and ecosystem function in lakes and flooded pits exposed to uranium mining activities in Northern SaskatechewanHelps, Devin Murray 25 May 2009 (has links)
Uranium mining activities have the potential to impact aquatic systems through mine drainage (runoff) and the release of treated effluent into nearby watersheds. Such anthropogenic exposure can lead to elevated concentrations of metals and major ions, which may impact aquatic biota. Previous studies have looked at the effects of water quality on aquatic biota within flooded pit lakes and natural lakes that have been exposed to various mechanisms of mining exposure. However, the literature often only examines the effects of a limited number of contaminants on a limited number of species. Researchers have rarely looked at the effects of multiple contaminants on species composition, biodiversity and ecosystem function in aquatic systems. This study uses a multivariate approach to look for relationships between water quality (24 variables), plankton species composition and abundance, biodiversity (richness and evenness) and ecosystem function among lakes exposed to mining activities (n = 18) and non-exposed reference lakes (n = 8). Lake water quality data was used to cluster lakes into groups. Lake groups were then overlain onto multivariate ordinations derived from species composition-abundance data to determine if species composition was related to water quality. Ecosystem function variables included planktonic phosphorus cycling and planktonic respiration. The classified lake groups clustered well on ordinations derived from species composition-abundance data suggesting that relationships exist between water quality and plankton species composition. However, ecosystem function was similar among the majority of lakes and flooded pits despite differences in species richness, species composition and species abundance. Only a small number of aquatic systems had ecosystem function properties that were different from the majority of lakes and pits. These systems had the greatest concentrations of contaminants and had very low biodiversity (richness and evenness) compared to the other systems. Despite having differences in plankton species composition and species richness, all lake groups were functionally similar. This suggests that functional redundancy in species composition may be present in the majority of lakes and pits in such a way that ecosystem function is maintained.
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Advancing cumulative effects assessment methodology for river systemsSeitz, Nicole Elyse 14 April 2011 (has links)
Increased land use intensity has adversely affected aquatic ecosystems within Canada. Activities that occur over the landscape are individually minor but collectively significant when added to other past, present, and reasonably foreseeable future actions, and are defined as cumulative effects. Existing approaches to cumulative effects assessment for river systems within Canada are ineffective. This thesis aims to improve the practice of cumulative effects assessment by evaluating current methodology for linking landscape change and river response over a large spatiotemporal scale. As part of this goal, I offer a framework for better incorporating science into current practices for cumulative effects assessment. The framework addresses the challenges involved in cumulative effects assessment, such as defining appropriate spatial and temporal scale, complex ecological and hydrologic pathways, predictive analysis, and monitoring. I then test the framework over a large spatiotemporal scale using a case study of the lower reaches of the Athabasca River Basin, Alberta. Three objectives are addressed: 1) changes in land use and land cover in the lower ARB for several census dates (1981, 1986, 1991, 1996, 2001) between 1976 (historic) and 2006 (current day) are identified; 2) linkages between landscape change and river water quality and quantity response are evaluated; and 3) results of the different methods used to link landscape stressors with stream responses are compared. Results show that the landscape has changed dramatically between 1976 and 2006, documented by increases in forest harvesting, oil sands developments, and agricultural intensity. Secondly, results suggest that linear regression tests combined with regression trees are useful for capturing the strongest associations between landscape stressors and river response variables. For instance, water abstraction and agricultural activities have a significant impact on solute concentrations. This suggests that water abstraction and agriculture are important indicators to consider when conducting a watershed cumulative effect assessment on a similar spatiotemporal scale. The thesis has strong implications for the need for improved water quality and quantity monitoring of Canada‟s rivers. The research provides a means of identifying appropriate tools for improved watershed cumulative effects assessment for scientists and land managers involved in the environmental impact assessment process and protection of Canada‟s watersheds.
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Bayesian Methods to Characterize Uncertainty in Predictive Modeling of the Effect of Urbanization on Aquatic EcosystemsKashuba, Roxolana Oresta January 2010 (has links)
<p>Urbanization causes myriad changes in watershed processes, ultimately disrupting the structure and function of stream ecosystems. Urban development introduces contaminants (human waste, pesticides, industrial chemicals). Impervious surfaces and artificial drainage systems speed the delivery of contaminants to streams, while bypassing soil filtration and local riparian processes that can mitigate the impacts of these contaminants, and disrupting the timing and volume of hydrologic patterns. Aquatic habitats where biota live are degraded by sedimentation, channel incision, floodplain disconnection, substrate alteration and elimination of reach diversity. These compounding changes ultimately lead to alteration of invertebrate community structure and function. Because the effects of urbanization on stream ecosystems are complex, multilayered, and interacting, modeling these effects presents many unique challenges, including: addressing and quantifying processes at multiple scales, representing major interrelated simultaneously acting dynamics at the system level, incorporating uncertainty resulting from imperfect knowledge, imperfect data, and environmental variability, and integrating multiple sources of available information about the system into the modeling construct. These challenges can be addressed by using a Bayesian modeling approach. Specifically, the use of multilevel hierarchical models and Bayesian network models allows the modeler to harness the hierarchical nature of the U.S. Geological Survey (USGS) Effect of Urbanization on Stream Ecosystems (EUSE) dataset to predict invertebrate response at both basin and regional levels, concisely represent and parameterize this system of complicated cause and effect relationships and uncertainties, calculate the full probabilistic function of all variables efficiently as the product of more manageable conditional probabilities, and includes both expert knowledge and data. Utilizing this Bayesian framework, this dissertation develops a series of statistically rigorous and ecologically interpretable models predicting the effect of urbanization on invertebrates, as well as a unique, systematic methodology that creates an informed expert prior and then updates this prior with available data using conjugate Dirichlet-multinomial distribution forms. The resulting models elucidate differences between regional responses to urbanization (particularly due to background agriculture and precipitation) and address the influences of multiple urban induced stressors acting simultaneously from a new system-level perspective. These Bayesian modeling approaches quantify previously unexplained regional differences in biotic response to urbanization, capture multiple interacting environmental and ecological processes affected by urbanization, and ultimately link urbanization effects on stream biota to a management context such that these models describe and quantify how changes in drivers lead to changes in regulatory endpoint (the Biological Condition Gradient; BCG).</p> / Dissertation
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Study on the near-shore fishery resources and management-A case study on Tainan coastLin, Yuong-Shiu 22 April 2011 (has links)
This research includes investigations of the ocean water quality of Tainan, its contamination sources and examines its relations to the fishing industry. It also explores the connection between topographical changes and evolution of the Tainan fishing industry and by using relevant information of ocean weather, tidal waves, wind speed, wind direction, and typhoon to study its relatedness to the developments of the fishing industry. It will further look at the role of the government in pollution prevention measures of the ocean, which specific laws and regulations must be setup and put into motion, so it can have a key role and have authoritative power. The quality of the marine environment has obviously deteriorated as the economy developed, and public hazard signals should become a severe issue that the government should face. Marine biological resources are common assets of the humankind and it is closely related to human survival, therefore, marine ecosystem must be properly preserved so it can maintain its most natural state and its resources can be sustained for our next generation to enjoy.
The conclusions of this research includes suggestions for planning marine contamination report system and advice the government to set up an award system to encourage local coastal residents and fishermen to establish marine patrol volunteer organizations and report immediately if they discover any oil contamination in the ocean. Also, to target the characteristic of fishing industry depending on natural resources, it offers a suggested direction for important policies of reinforcing environmental protection and resource preservation and recommends putting in as much protective reef as possible within 3 nautical miles, which are designed to stop trawling nets but does not damage fishing gears. It also advocates waste reduction and reuse of recycled items and by following the treatment method for sewage, if we can transform wastes into usable resources and naturally reduce the pressure of further treatments, the proper handling for marine wastes should be cautiously designed in order to directly and effectively resolve the problem of large amount of wastes. It calls upon the government to appropriately develop, use, and sustainably manage the rich marine resources that we possess. In addition to reinforcing marine-related laws and regulations (amendment), it also aims to strengthen the protection and management of marine territory, actively engage in related research and development of marine resource use to enhance the development of our nation¡¦s marine resources, the technology, and its standards. Finally, by investigating from a sustainable use of the ocean point of view, it is possible to explore new directions for the future developments of the fishing industry and propose possible development strategies, and by examining the current condition of Tainan's coastal fisheries resources, it offers relevant resource management plans for industry-related management units and businesses to take into consideration. Our nation has the ability and conditions to develop marine industry and under the demands of international competition and domestic development, a continuation for the marine industry development is of absolute importance and necessity.
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Water quality from advanced and conventional treatment process of raw water relating to quality and quantityLin, Jen-Yao 29 June 2011 (has links)
The purpose of this study is to study the effect of water quality and quantity of raw water on advanced and conventional treatment processes. We are using data of water quality and quantity to investigate difference of quality of treated water in water treatment plant. Finally we compared items of ware quality ( turbidity, free residual chlorine, total hardness, conductivity, pH, NH3-N) whether passed the Taiwan¡¦s national standard of drinking water or not. We are hoping the treated drinking water will all fit the goal of high quality.
Results show that high variation of turbidity was found from May to October in every year. The high turbidity was frequently occurred from 9.9% (2008) to 39.5% (2010). It indicated the worsen trend of water quality of raw water is increased yearly. In all monitoring items of water quality, turbidity, conductivity, NH3-N was greatly influenced in seasons from June to September. The rest items had no significant affect by season¡¦s variation. The removal efficiency in items of water quality of advanced and conventional WTP we found there were high value at hardness and TDS with 49.3% and 43.3% respectively. These items, water quality of treated water (such as turbidity, free residual chlorine, total hardness, conductivity, pH, NH3-N), were all pass the current drinking standard in Taiwan ( i.e., turbidity¡Õ2NTU¡BTDS¡Õ500mg/L¡B6.0¡ÕpH¡Õ8.5¡B0.2mg/L¡Õfree residual chlorine¡Õ1.0mg/L¡BNH3-N¡Õ0.1mg/L ).
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Characteristic analysis and reuse potential assessment of the steel-making desulfurization slagLiang, Yong-siang 24 August 2012 (has links)
Furnace slag is the by-product from steel making process. Desulfurization slag (DS) was produced from the desulphurization process of molten irons in high temperature furnaces processes. DS is heterogeneous oxide materials which are compounded by some main oxides such as SiO2, FeO, CaO, SiO2, MnO, Al2O3, and MgO due to their mass percentage. Because DS has high pH characteristics (12.5), this limits its recycle and reuse. The objective of this study was to evaluate the potential of applying DS as the construction materials or amendments in the aquacultural industry to improve the aqualcultural water quality in the fish farm. The basic characteristic analyses show that the major chemical compositions of powder DS were CaO, SiO2, Fe2O3 and Al2O3. The major crystalline phase composed of SiO2, Ca(OH)2 and CaCO3. Results of DS release test show that when DS could increase pH and alkalinity value in water. Results of micro-structure analysis of powder DS surface showed there were many non-porous materials and heavy metals on DS. Results from the nutrient removal tests show that the ammonia nitrogen adsorption capacity were 0.036 mg/L and 0.069 mg/L when the initial concentration were 10 mg/L and 30 mg/L, respectively. Results form the adsorption model validation test indicate that the adsorption phenomena could fit in Langmuir model. The adsorption capacities of phosphate were 26.4 mg/L and 76.6 mg/L when the initial phosphate concentrations were 10 mg/L and 30 mg/L, respectively. The calculated values of thermodynamic parameters show that the adsorption reaction for ammonia nitrogen was endothermic non-spontaneous process, and the adsorption reaction for phosphate was exothermic spontaneous process. However, the enthalpy change (£GH) showed that adsorption reaction of DS for ammonia nitrogen was physical adsorption, and the adsorption reaction for phosphate was chemical sorption. In the algae culture experiment, results show that when 25 mg/L of DS was supplied, the growth rate of Chlorella sp. could be enhanced. Thus, the powder DS could enhance the growth of Chlorella sp. A field study using a fish farm as the study site was conducted to evaluate the impact of DS on fish farm water quality when DS was applied as the filling and construction materials of the fish farm. Results show that addition of DS had no significant effect on groundwater and pond water quality. Results from the organic matter analysis of the pond water using EEFM show that humus-like and soluble microbial product (SMP) materials were detected. The dominant algae in the pond water included Scenedesmus sp. and Chlorella sp. indicating the pond water quality was in good conditions. Addition of DS would increase of water alkalinity preventing the acidification of pond water due to the fish feed and fish excreta. Results of heavy metal analysis of soil, groundwater, and pond water complied with the relevant environmental standards. Results of this study will aid in understanding the characteristics of DS and the results will be useful in designing a DS reuse system to achieve the zero waste and resource reuse goal.
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Evaluation of Groundwater Characteristics Using Multivariate Statistical Method: a Case Study in KaohsiungWang, Mei-hsueh 24 August 2012 (has links)
It is not easy to state clearly to the public for quality of groundwater bodies, even if there are a large number of effective water quality data, it is still hard to combine and induct,and it often occurs in different units have each put forward to explain on the test results.Multivariate statistical analysis method can simplify high complex data into a representative function of the small number of factors, clearly explained to a group of inter-relationship of the original variables, or to be clustered and identified according to the similarity between the data to understand the reason behind the formation of certain phenomena, so this study utilize it to explore the groundwater characteristics.
In this study, monitoring data come from the Kaohsiung city 48 groundwater monitoring wells of the EPA National Water Quality Monitoring Information website database, apply SPSS12.0 package software to execute multivariate statistical analysis, including factor analysis ,cluster analysis and discriminant analysis, and thus induction, sorting and classification of water quality characteristics, evaluating the causes of pollution and local area characteristics. The results of factor analysis to obtain the groundwater quality of the Kaohsiung region 4 representative factors: the factor of salinization, organic pollution factor, the factor of ore melting and acid-base factor. Four principal component factors instead of the 17 analysis projects of the regional groundwater quality in Kaohsiung city, the variance amounted to 78.3%. Use of cluster analysis of the 48 monitoring wells in the region is divided into four groups, according to the different nature of the monitoring data and the nature of similarity and group, to investigate the correlation between the monitoring well water quality within each cluster and the main factor, and by monitoring wells position to distinguish between the average underground water quality of inland area than the coastal area, we can get the results of seawater intrusion and salinization phenomena in coastal area, and monitoring wells located in the Cijin district are polluted by the pH factor. Kaohsiung regional groundwater quality is generally in the case of hard water to very hard water.
In order to understand the difference of the multivariate statistical analysis method and the general groundwater pollution index analysis, draw Piper water quality diamond cluster analysis diagram to compare the similarities and differences,the results show that the multivariate statistical analysis can supply a systematic analysis of variable data and the overall variations of the water quality, and objective clustering, while the general composite index analytcial method such as Piper, by the characteristic position to get the type of pollution, but difficult to explain the overall pollution characteristics. At last, in this study, the hope to recommend the pollution control assessment and prevention strategies of Kaohsiung city underground water.
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Synthesis of gold nano-particles in a microfluidic platform for water quality monitoring applicationsDatta, Sayak 15 May 2009 (has links)
A microfluidic lab-on-a-chip (LOC) device for in-situ synthesis of gold nano-particles
was developed. The long term goal is to develop a portable hand-held diagnostic
platform for monitoring water quality (e.g., detecting metal ion pollutants).
The LOC consists of micro-chambers housing different reagents and samples that feed to
a common reaction chamber. The reaction products are delivered to several waste
chambers in a pre-defined sequence to enable reagents/ samples to flow into and out of
the reaction chamber. Passive flow actuation is obtained by capillary driven flow
(wicking) and dissolvable microstructures called ‘salt pillars’. The LOC does not require
any external power source for actuation and the passive microvalves enable flow
actuation at predefined intervals. The LOC and the dissolvable microstructures are
fabricated using a combination of photolithography and soft lithography techniques.
Experiments were conducted to demonstrate the variation in the valve actuation time
with respect to valve position and geometric parameters. Subsequently, analytical models were developed using one dimensional linear diffusion theory. The analytical
models were in good agreement with the experimental data. The microvalves were
developed using various salts: polyethylene glycol, sodium chloride and sodium acetate.
Synthesized in-situ in our experiments, gold nano-particles exhibit specific colorimetric
and optical properties due to the surface plasmon resonance effect. These stabilized
mono-disperse gold nano-particles can be coated with bio-molecular recognition motifs
on their surfaces. A colorimetric peptide assay was thus developed using the intrinsic
property of noble metal nano-particles. The LOC device was further developed on a
paper microfluidics platform. This platform was tested successfully for synthesis of gold
nano-particles using a peptide assay and using passive salt-bridge microvalves.
This study proves the feasibility of a LOC device that utilizes peptide assay for
synthesis of gold nano-particles in-situ. It could be highly significant in a simple
portable water quality monitoring platform.
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Effects of Anthropogenic Nutrient Enrichment on Exotic and Restored Native Aquatic VegetationParnell, Allison 2011 May 1900 (has links)
Understanding how nutrient input into coastal wetlands influences aquatic vegetation and the fate of anthropogenic nutrient inputs can help improve water quality management plans. The goals of this study were to (1) compare nutrient concentrations in various storage compartments downstream from two point nutrient sources (a sewage treatment plant outfall and a residential detention basin) in Armand Bayou, a coastal brackish wetland in the Galveston Bay (Texas, USA) watershed, and (2) determine if nutrient storage in those compartments helped improve water quality downstream.
Water column nutrients can be assimilated by aquatic vegetation, adsorbed to sediment, or diluted within the system as distance from source input increases. To determine the fate of nutrients to Armand Bayou, I measured nutrient concentrations in the sediment, water column, pore water, and tissue of exotic and restored native plants downstream from a sewage treatment plant and a residential detention basin. To assess nutrient removal potential of a common exotic species, I determined relative growth and nutrient uptake rates of Eichhornia crassipes. Water column total nitrogen, NH₄⁺ and NO₃ˉ concentrations decreased by 95, 96 and 99 percent downstream from the sewage outfall (~2200 m distance). Water column NH₄⁺ and NO₂ˉ concentrations decreased by 93 and 75 percent downstream from the detention basin (~2500 m distance). Exotic species Alternanthera philoxeroides, Pistia stratiotes and E. crassipes showed higher aboveground/emergent tissue nutrient content than restored, native Schoenoplectus californicus for both tributaries. Schoenoplectus californicus had the largest biomass although appeared to be limited in its ability to remove nitrogen from the water column. Nutrient uptake rates by E. crassipes were low and did not change with increasing distance from nutrient source, but high relative growth rates in both tributaries suggest the nuisance potential of this exotic species. Low sediment and pore water nutrient concentrations for both tributaries suggest these compartments are not sinks. All plant species did not respond to changes in water column nutrient concentrations with increasing distance from source input suggesting dilution to be the main factor in water column nutrient decline for both tributaries.
This study will provide water quality resource managers guidance on the development of total maximum daily loads (TMDLs) for water bodies impaired by high nutrient loading and the implementation of wetland plants efficient in nutrient removal for water quality improvement.
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Economical evaluation for the improvement strategy of drinking water quality by advanced water treatment in Greter Kaohsiung DistrictHsieh, Hsun-Huang 17 June 2004 (has links)
Economical evaluation for the improvement strategy of drinking water quality by advanced water treatment in Greter Kaohsiung District
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