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This study examines the sedimentary and morphological flood record of the River Tyne, northern England, over the last 400 years. Temporal trends in flooding and spatial variations in the timing and nature of river response to floods (flood "effectiveness") are investigated at 3 reaches representative of upland, piedmont and lowland locations in the Tyne catchment. Deposition of coarse flood sediments in headwater tributaries of the River Tyne appears to be strongly related to flood water:sediment ratios that is primarily controlled by sediment supply. Cobble - boulder bars, sheets and splays are deposited under Newtonian flow conditions from flows with relatively low sediment concentrations. Boulder berms and lobes result from floods with high sediment loads, associated with slope-channel coupling. Flood sedimentation in lower reaches of the Tyne comprises vertical accretion of fine-grained, well-bedded sediments at overbank and within-channel locations. Larger floods can be identified on the basis of textural discontinuities that reverse the overall fining-upward sequence. Estimation and interpretation of flow magnitude in each setting is complicated by progressive river bed incision over the period of investigation and significant changes in sediment supply which have affected the nature of flood sedimentation. Trace metal dating of fine-grained, and lichenometric dating of coarsegrained, flood units has enabled detailed and temporally well-defined records of channel and floodplain response to flooding to be established within the Tyne catchment. Since 1600 A.D. fluvial activity at all 3 study reaches has been characterised by alternating periods of river bed incision and stability. Episodic changes in vertical channel stability appear to coincide with non-random decadalscale fluctuatiions in flood frequency: 3 periods with distinct clustering of large floods (1740-1790, 1860-1899, 1940-1965) were associated with vertical instability (channel trenching) throughout the Tyne basin, while intervening periods with relatively few exceptional floods were associated with channel accretion and floodplain rebuilding in general, but with significant upstream/downstream variation. Distinct clustering in the timing of large floods correspond with shortterm hydroclimate changes associated with fluctuations in the configuration of the upper atmosphere. These findings have significant implications for longer-term fluvial development and interpretaion of Holocene alluvial sequences.

There is currently worldwide interest in the effect of human activity on tile global environment, especially the effect of greenhouse gases and land-use change on the global climate, and models are being developed to study both global change and the local effects of global change. The research reported here (funded by CNPq-Brazil) involves the development of GRASP:Groundwater Recharge modelling Approach with a Scaling up Procedure. GRASP has been integrated into the UP (Upscaled Physically-based) macromodel, developed under the UK NERC TIGER programme, which is designed for studying the effects of climate and land-use change on the availability and quality of water resources. The UP macromodel will be coupled to the UK Meteorological. Office's Unified (weather and climate) model to create a state-of-the-art coupled atmospheric/hydrological model. Several important requirements for the design of new large-scale hydrological models are identified in a wide ranging review on GCMs; (General Circulation Models) and physically -based hydrological modelling, and these requirements have been applied in the development of GRASP(and UP). The main requirements are a physical basis, proper treatment of spatial variability, and simplicity. Using the concept of partial analysis, two point-scale models, SM (Soil Moisture content approach) and TF (Transfer Function approach), are developed for recharge, both based on the one-dimensional Richards' equation. SM is a simple two-parameter model relating recharge to water storage in the unsaturated zone, and several unsuccessful attempts are made to link its parameters to physical propcrties. TF is a transfer function model, and is parameterised using the matric potential and unsaturated hydraulic conductivity functions using a new approach developed especially for GRASP. Both SM and TF are verified against numerical solutions of Richards' equation.

An analysis of a number of flood routing methods has been carried out in this study. These methods are namely, the Muskingum-Cunge Method, the Variable Parameter Diffusion Method, the State Variable Kinematic Wave Model, and the state variable modelling of nonlinear Muskingum Model. The Muskingum-Cunge and Variable Parameter Diffusion Methods are recommended for use on British Rivers by the Natural Environment Research Council flood studies report, 1975.In using numerical flood routing model, it is very important to calculate the model parameters. For instance storage routing models require a suitable form of storage-discharge relationship. Past flow records were used for the above calculation. The state Variable Kinematic Wave Model has been applied for routing the flood hydrograph through river reaches. The stage and discharge are computed by a kinematic wave routing technique using the state variable approach in which the one-dimensional differential equations of unsteady flow are solved by state and output equations of the state variable model. The nonlinear Muskingum equation has been solved using the state variable modelling technique. Two parameter estimation techniques namely, Hooke-Jeeves and linear regression, are employed for the calibration of the nonlinear Muskingum model parameters (a, x, and m).The applicability of the flood routing model computer programs to different flood events of different seasons for reaches of both the Rivers Wear and Tees is demonstrated. Discriptions of the geology and hydrological data for reaches of both the Rivers Wear and Tees are given in this study. The computed and observed hydrographs of flood routing models used in this study are compared.

In response to the likely future change in the Canadian Guidelines regulating the maximum allowable concentration of trihalomethanes (THM) in potable water, an investigation into the possible causes and variability of THM precursors was conducted during the summers of 1990 and 1991 at Lake Memphremagog in south-eastern Quebec. A number of associated parameters were correlated with THM formation potential (THMFP) with respect to season, depth and position on the lake. The THMFP was quantified indirectly by measuring the THM concentration present after chlorination under standard conditions. / THM concentrations in the samples were found to exceed the US EPA standard of 100 $ mu$g/L, sometimes considerably. There did not appear to be any statistically significant contribution to THMFP from human activity. No close agreement was observed between THMFP and any of the associated parameters for the lake as a whole. A few correlations were found between THMFP and nutrient concentrations at individual sites.

x, various paging : ill. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--Dept. of Mathematics, University of Adelaide, 1971

x, various paging : ill. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--Dept. of Mathematics, University of Adelaide, 1971

Thesis (M.S.- Fishery Management)--University of Arizona. / Includes bibliographical references (leaves 70-74).

Thesis (Ph.D.)--The University of Toledo, 2006. / (UnM)AAI3218587. Adviser: Daryl L. Moorhead. Source: Dissertation Abstracts International, Volume: 67-05, Section: B, page: 2328.

Thesis (M.S.)--University of Wisconsin--Madison, 1970. / Title from PDF title page (viewed Nov. 10, 2008). Includes bibliographical references. Online version of the print original.