Surface ozone (O3) is one of the most toxic and abundant air pollutants. It has deleterious effects on human and animal respiration processes, and adversely affects plants. Four sites were selected for monitoring ambient O3 in the Durban metropolitan area: Botanic Gardens, University of Natal (UND), top of Kloof Gorge, and Mooi River. At each site tobacco Bel-W3 bioindicators, and NO2 and O3 passive diffusion tubes were placed. An O3 analyser (Dasibi 1108) was situated at the UND site. Monitoring was carried out for four weeks during summer, autumn and winter at each site, and during spring at the UND site. Two weeks of data from the diffusion tubes were collected during spring, from the Nelspruit area, Mpumalanga. Ozone concentrations measured with the Dasibi at the UND site were low in comparison to other urban-industrial areas in the world, with hourly values falling between 5ppb and 10 ppb. The highest hourly mean maximum recorded was 40ppb. A general spring/winter maximum and summer minimum was observed. This is typical of subtropical locations, where subsidence in prevailing anticyclonic circulation occurs. Diurnal characteristics included early morning minima and maxima at 12h00 in spring and summer, and maxima approximately two hours later in autumn and winter. This pattern was typical of that found in polluted environments, the magnitude, however, being lower. An unusual secondary nocturnal peak occurred during autumn, winter and spring. This could have been due to the long-range transport of relatively O3-rich air from a non-urban, high altitude inland area. Ozone concentrations were not strongly influenced by meteorological variables. Diffusion tube data indicated low O3, however, the coefficients of variation were high, implying a lack of precision in this technique. This technique would have to be improved before data obtained could be regarded as valid. Nitrogen dioxide, NO2, one of the precursors to O3, was monitored using diffusion tubes at the same sites. Concentrations were highest closer to the city centre, the highest concentration being 31ppb in autumn. In the Mpumalanga study, NO2 concentrations were higher in the city of Nelspruit than the surrounding areas. No significant differences were found in the O3 concentrations between the Mpumalanga sites. The tobacco plants showed the highest visible leaf injury in winter, corresponding with the higher Dasibi values, but there were no significant differences between the sites, and no significant differences in chlorophyll contents between the sites. In this study, O3-induced injury occurred below the previously established threshold of 40ppb. / Thesis (M.Sc.)-University of Natal, Durban, 1998.

The overall goals of this project were: (1) to develop a microbiological ecological indicator that would describe military land disturbance, (2) integrate previously collected ecological indicator data from five separate research teams, and (3) produce knowledge maps with the resulting information that illustrates how the selected indicators are involved in ecosystem processes. To address goal one, soil samples were obtained from four levels of military traffic (reference, light, moderate, and heavy) with an additional set of samples taken from previously damaged areas. Using the soil microbial biomass and community composition as ecological indicators, reproducible changes showed increasing traffic disturbance decreases soil viable biomass, biomarkers for microeukaryotes and Gram-negative bacteria, while increasing the proportions of aerobic Gram-positive bacterial and actinomycete biomarkers. To address the second goal, ecological indicator data was collected by five separate research teams. Landmanagement categories (LMCs) were developed that described the uses or causes of the ecological effect from military use(s) of land. A mechanism of multiple solutions was developed that combined the results and tested the efficacy of the proposed indicators. Results from the integration effort showed that Soil A horizon depth and soil compaction were important soil physical indicators of military land disturbance. Soil Nitrogen and Carbon content were important soil chemical indicators of land use. Soil mineralization rate, soil respiration, microbial composition and Beta Glucosidase activity were important microbiological indicators. Important plant indicators included tree stand age, canopy iv cover, understory cover, plant life form and legumes. To address the third goal several knowledge maps were developed, and the results from the integration of indicator data were pooled and studied for the relationships between them. By displaying the indicators in this fashion, it was hoped that the knowledge of what the indicators represent to the functioning of the ecological system could be understood. For the practitioner, this knowledge should lead to actionable products or at least a better understanding of what is being measured and how it relates to broader ecosystem dynamics.

In recent years, sustainable development has become one of the most important issues internationally. Many indicators related to sustainable development have been proposed and implemented, such as Island Taiwan and Urban Taiwan. However the missing values come along with environmental monitoring data pose serious problems when we conducted the study on building a sustainable development indicator for marine environment. Since data is the origin of the summarized information, such as indicators. Given the poor data quality caused by the missing values, there will be some doubts about the result accuracy when using such data set for estimation. It is therefore important to apply suitable data pre-processing, such that reliable information can be acquired by advanced data analysis. Several reasons cause the problem of missing value in environmental monitoring data, for example: breakdown of machines, ruin of samples, forgot recording, mismatch of records when merging data, and lost of records when processing data. The situations of missing data are also diverse, for example: in the same time of sampling, some data records at several sampling sites are partially or completely disappeared. On the contrary, partial or complete time series data are missing at the same sampling site. It is therefore obvious to see that the missing values of environmental monitoring data are both related to spatial and temporal dimensions. Currently the techniques of data imputation have been developed for certain types of data or the interpolation of missing values based on either geographic data distributions or time-series functions. To accommodate both spatial and temporal information in an analysis is rarely seen. The current study has been tried to integrate the related analysis procedures and develop a computing process using both spatial and temporal dimensions inherent in the environmental monitoring data. Such data imputation process can enhance the accuracy of estimated missing values.

The coupling of real-time measurements and numerical models will be important in overcoming the challenges in environmental and oceanographic assessments in surface waters. Continuous monitoring will take advantage of current state-of-the-art in sensor development, remote sensing technology. The numerical modeling tools available exist in many different forms and varying levels of complexity from depth integrated one-dimensional (1-D) models to full three-dimensional (3-D) models. Common to all are the constraints and forcing required in driving the models. These include hydrodynamic and barometric information, which are relatively difficult to obtain given the time scale of the bio-chemical and physical processes governing the fate and transport of the constituents of interest. This study is focused on the development of a framework that couples real-time measurements and numerical simulation for tracking constituents in surface waters. The parameterization of the mixing and turbulent diffusion impacts the formulation of the constituent-transport governing equations to the extent that the numerical model is being driven by near real-time observations of hydrodynamic data and the consequent evaluation of model coefficients. The effects of shear-augmented diffusion processes in shallow embayment and near-shore waters are investigated in order to develop algorithms for obtaining a shear diffusion coefficient, Ke from shear-current measurements and turbulent diffusion-coefficient, Kz measured by the auto-correlation function, Rτ of the velocity time-series. Typically, the diffusion coefficients are measured through tracer experiments as determined by the time rate of change of the variance of a growing patch (K = ½ dσ2 /dt), which introduces the concept of diffusion length-scale (or time-scale). In this study, the dye-tracer experiment was used, not so much in the context of evaluation of a diffusion coefficient, but within a modeling framework to validate a numerical scheme driven by real-time hydrodynamic observations. Overall, the effect of shear-currents in shallow wind-driven estuaries is studied using a prototype bay typical of the Texas Gulf-coast. A numerical model was developed and used in testing these hypotheses through a series of dye-tracer experiments under varying meteorological conditions.

Thesis (Ph.D.) -- University of Glasgow, 2008. / Ph.D. thesis submitted to the Division of Environmental and Evolutionary Biology, Institute of Biomedical and Life Sciences, University of Glasgow, 2008. Includes bibliographical references. Print version also available.

No description available.

Thesis (M.S.)--University of Arizona, 1990. / Includes bibliographical references (pp. 197-199).

Thesis (M.S.)--Northwest Missouri State University, 2007. / The full text of the thesis is included in the pdf file. Title from title screen of full text.pdf file (viewed on January 25, 2008) Includes bibliographical references.

Thesis (M.S.)--University of Nevada, Reno, 2008. / "May, 2008." CD-ROM contains Adobe Acrobat copy of thesis, power-point presentation entitled: Effectiveness and reliability of photo-pair interpretation, and photographs taken during the study. Includes bibliographical references. Library also has microfilm. Ann Arbor, Mich. : ProQuest Information and Learning Company, [2009]. 1 microfilm reel ; 35 mm. Online version available on the World Wide Web.

Thesis(MA)--University of Stellenbosch, 2007. / Bibliography. Also available via the Internet.