Digitized by Kansas Correctional Industries

This thesis takes a material culture approach to exploring how the Thames was experienced from 1660 to 1830. It conceives of the river as a material object, constantly shaped by its designers, makers and users. The river was an essential part of the day-to-say lives of Londoners and visitors and framing the river as a kind of object allows an exploration of the material-human interactions on a number of different levels, from transformative changes to the river's geography to more everyday contact at work, leisure and home. The thesis understands the river's changing relationship to key transformations in Britain's long eighteenth century as London became the metropolis of an expanding commercial and territorial empire. The first chapter addresses the redesigning of the river, tracing the building projects imposed by political and mercantile interest groups which transformed riverfront architecture with six new bridges and vast dock complexes and aimed to control how people experienced the river's relationship to the nation and its growing empire. The second chapter uses watermen's court records and criminal trials alongside material remnants of river work to show that watermen asserted an informal control over the river space which was increasingly eroded by the desire to secure imperial trade against theft. Chapter three explores the growing use of the river as leisure space, using diaries to identify quotidian leisure activities on the river. It highlights the increasing commercialisation of riverine leisure as boat trips and guidebooks proliferated. The final chapter uses objects depicting the Thames to show how the river filtered into everyday lives through consumption, often constructing a picturesque view for a polite audience. Like the other material engagements with the river, these objects constructed an experience of the eighteenth-century waterway which glorified commerce and obscured from everyday experience the realities of an imperial river.

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acase@tulane.edu / Ecogeomorphology is the study of interactions and feedbacks between the physical surface processes and biological communities in an ecosystem. These interactions are under-studied in wetlands associated with river deltas, and are of vital importance to the deteriorating wetlands of South Louisiana. As the state of Louisiana implements its Comprehensive Master Plan for a Sustainable Coast, which relies heavily on diverting Mississippi River water in order to create new wetlands, a detailed understanding of ecogeomorphological relationships is required to create accurate predictive models to design and assess future projects. This research is comprised of three studies of such relationships in the West Bay Sediment Diversion near Venice, LA, and has resulted in the following key findings: 1) the composition of the buried seed bank suggests a shift from river-derived to within-system propagules as the marsh develops, 2) emergent plant roots increase the cohesion of marsh soils, especially when grasses, sedges, and woody species dominate the vegetation, and 3) a competition experiment between the native sedge Schoenoplectus deltarum and the invasive grass Phragmites australis indicated that the two species performed approximately equally in mixture, regardless of abiotic stressors, while the stressors did affect productivity of each species grown in monoculture. These three studies are unified by the role of wetland vegetation as an increasingly important autogenic modifier of other wetland processes during the early development of the marsh. / 1 / Alexander D Ameen

acase@tulane.edu / Though rivers are inextricably linked in our minds with an intermittently flooded overbank environment, surprisingly little is known about the sedimentary processes that operate there, or how they interact with those of the river. The knowledge gap is acute in deltas, where dense populations often necessitate tightly engineered control over flow patterns, leading to disconnected overbank environments that no longer receive input from the main channel. However, the need to understand sedimentary function in the overbank is also acute in deltas, as rising relative sea levels create an urgent need to manage water and sediment resources. This dissertation is presented as three primary chapters, each of which examines a different aspect of the hydrodynamic and sedimentary connection between a river’s channel and its overbank environment. In Chapter 2, my coauthors and I ask which factors enhance overbank sediment retention, and what retention rates might be considered typical in deltas. We compare the sediments stored in a crevasse splay to those transported by the river and conclude that retention rates approaching 100% might be achievable in settings that are not exposed to coastal processes. Chapter 4 is also concerned with spatial patterns of sedimentation on a delta. In it we use physical experiments to examine the influence that floods play in mobilizing sediments from the channel and storing them in the overbank environment. We find, counterintuitively, that an experiment whose input included floods has a lower proportion of floodplain to channel deposits preserved than an experiment with a constant input. Chapter 3 is focused on water and sediment dynamics in the channel in a region where significant flow is lost to the overbank environment. Here we present measurements from channel networks in the Mississippi River’s Birdsfoot Delta and show that flow loss along the channels is a critical control on channel function that causes channels of disparate sizes to behave similarly. We use our field results to inform a numerical model of channel bed evolution in a region with flow losses, and conclude that the modern flood control system in the Lower Mississippi River may have significantly changed the bed morphology. / 1 / Christopher R. Esposito

This study investigated trace essential metals (Cu, Zn and Cr) and non-essential metals (Pb, Cd and Hg) in water, sediment and tissues of water spinach, snake head fish and swamp eel from the Saigon River. Sampling was conducted from January to December 2004 at three sites. Three water and sediment samples, edible parts of twenty water spinach (Ipomea aquatica) samples (leaves and stems), twenty snake head fish (Channa striata) and twenty swamp eels (Monopterus albus) were collected at each site. Water, sediment and biota tissues were analysed for Cu, Zn, Cr, Pb, Cd and Hg following the method of USEPA, AOAC and NFTA. Results showed that Cu, Zn, Cr, Cd and Hg in water from the river was not higher than the maximum permitted level for protection of aquatic life by the national standards while the average Cu concentration in sediment was found to be close to the Effects range- low value and within the slightly polluted range (25- 50 ìg.g-1 dry weight). The results also showed that the river sediment was considered to be contaminated by Zn and Hg in comparison with contaminated sites in Australia and in Thailand. In water spinach, no Cu deficiency was found but Zn was accumulated. No accumulation of Cr, Cd and Hg was revealed but Pb was detectable. The results indicated that snake head and eel may have Cu deficiencies. Pb and Hg were found to be bioaccumulated in the muscle of snake head and eel at some sites on some occasions, but the levels were small. The results showed that metal in sediment liver of snake head muscle of snake head and eel water. The metals in water spinach decreased in the order Zn Cu Cr Pb Cd and Hg; in snake head the metal concentrations decreased in the order Zn Cu Cr PbHgCd and in eel as Zn Cu Cr PbCd and Hg. The ANOVA test showed no significant relationship between metals in the water and sediment and biota. Therefore it was concluded that the metals in the selected biota samples did not reflect the metals in the environment. The essential metals Cu, Zn and Cr were found to decrease at the end of the dry season and then increase at the end of the rainy season. The seasonal variations of metals in the river and biota maybe a result of the change of temperature in the area and the need for essential metals in the reproduction of fish. The results of this study clearly demonstrates that water spinach, snake head fish and swamp eel are not potential bio-indicators for metals in the Saigon River since they did not reflect concentrations of metals in their environment. It was also concluded based on consumption rates that water spinach, snake headfish and eel from the Saigon River do not present any potential health risk to consumers. However, attention should be paid to controlling the load of pollutants entering the river to avoid such risks and future problems.

The probable pollution distribution and flushing times have been calculated for the Columbia River Estuary, a coastal plain estuary. The pollution distribution was determined by the fresh water fraction and by the diffusion equation. The flushing times were calculated by the modified tidal prism method and by the fraction of fresh water, These methods are explained and discussed in the study. The widely varying river flow and resulting salt water intrusion were considered, as well as the varying semi-diurnal tidal range. These changing factors cause a complex variation in estuarine classification from well-mixed to stratified. The data used was taken principally from the U. S. Corps of Engineers current measurement program of 1959. The data show a stronger flow on the north side of the estuary during flood tide and a stronger flow on the south side during ebb tide. Due to this fact, the estuary was also treated as two separate channels in calculating the pollution distribution. The results of the various calculations for combinations of conditions are given in this study. A comparison of the different methods is also summarized. The estuary has been found to have a relatively short flushing time, even under low river flow conditions. The variation in strength of flow from the north side to the south side has been shown to produce pollution distributions not normally expected in an estuary. / Graduation date: 1965

Graduation date: 1961

Sediment samples were collected from eight sampling sites along the Yaquina Estuary, Oregon from Yaquina Bay to Elk City near the head of the estuary. Samples were collected in November 1973, February 1974, May 1974 and August 1974 from two or three intertidal levels depending on the magnitude of the intertidal area exposed at low tide. Concurrent sediment and water samples were obtained for the determination of water temperature, salinity, sediment size, and percentage of organic carbon and cabonate in each sample. Incident light and exposure period data were obtained for the sampling year. A total of 36,564 diatoms identified and counted in 71 samples was separated into 390 taxa (species or varieties). Of the 390 taxa, 31%, representing 30% of the total cell count, could not be identified from available literature. The relative abundance values of the taxa were utilized for the comparisons of several community composition parameters (the Information measure, Simpson's diversity index, redundancy, niche breadth, and a measure of similarity) which were used for comparisons of spatial and temporal distributions of sediment-associated diatom assemblages within the estuary. Multivariate analyses (clustering, disciminant analysis, principal components, canonical correlation) of species and environmental data were employed to analyze the distribution of sediment-associated diatom assemblages relative to the sampling strategy and to environmental gradients. The distribution of sediment-associated diatoms in Yaquina Estuary was regulated primarily by mean salinity and characteristics of the sediment. Above Yaquina Bay the prominent taxa exhibited overlapping distributions along the salinity gradient to a location in brackish water where the mean salinity was approximately 5°/oo. Here, a relatively sharp discontinuity in the diatom flora existed which appeared to be the product of the biochemical and biophysical mechanisms involved in osmotic regulation of mesohalobian and oligohalobian assemblages. Relatively large disparities in the structure of sediment-associated diatom assemblages were found within relatively small local areas of Yaquina Bay. These differences were attributed to the properties of the sediment, Responses of the diatom assemblages to light intensity, temperature and exposure to intertidal emergence were not obvious. Approximately one-half of the numerical variation in the diatom flora apparently was related to factors other than the physical and chemical variables considered in this study. Comparisons of previous distributional surveys in Yaquina Estuary indicated that the diatom flora associated with the sediments was dissimilar in species composition to proximal epilithic, epiphytic and planktonic diatom assemblages. Species diversity was generally high throughout the intertidal sediments, irrespective of tidal height and season, while redundancy was generally low. High diversity values may represent contamination of samples, behavioral-physiological adaptations of the sediment flora, or the spatial heterogeneity of intertidal sediments. / Graduation date: 1977

Relationships among the surface wind, horizontal synoptic-scale pressure gradient and topography are studied in the Willamette Valley in western Oregon. Terrain features alter the standard surface wind-pressure gradient relationship such that the angle between the surface wind and the surface geostrophic wind is most frequently 60°. In winter the surface flow is predominantly southerly and surface geostrophic flow varies from southerly to westerly. Little diurnal change occurs in the average surface wind, the average surface geostrophic wind and their relationship with each other because the air in the valley is generally stably stratified throughout the day. Partially in response to the northward extension of the subtropical anticyclone summertime surface winds and surface geostrophic winds are northerly, except during afternoon episodes of marine air invasion when surface winds are westerly. The pressure gradient is 88% less intense in summer but the ratio of the magnitudes of the surface wind and surface geostrophic wind, R, is 125% greater than in winter. However, a sharp summertime morning maximum in R of -0.67 is diminished by early afternoon as differential surface heating establishes a strong afternoon pressure gradient. When the surface geostrophic wind vector is cross-valley, the surface wind is still most frequently parallel to the valley and the surface geostrophic wind speed is largest and most variable. Because of the importance of terrain and meso-scale events, little correlation between the surface winds and synoptic-scale pressure gradient is found. / Graduation date: 1975