The distribution of macroinvertebrate communities is influenced by a myriad of abiotic environmental factors. However, many of these environmental factors do not occur randomly within a river system. Rather, they occur as a result of geomorphological processes that operate hierarchically to constrain the expression of environmental factors at successively nested levels. As a result of the hierarchical expression of geomorphological processes, environmental factors occur at characteristic scales within a river system and can be used to define spatial scales of river system organisation. Previous studies have examined multiscale patterns of benthic macroinvertebrate community distribution using scales of measurement such as ecoregions, catchments, rivers, reaches and functional habitats. However, none of these studies used scales derived from a geomorphological hierarchy to examine patterns of macroinvertebrate distribution. Given that macroinvertebrates are often deterministically influenced by environmental factors, and these environmental factors occur at characteristic scales within a geomorphological hierarchy, it is possible that the multiscale distribution of macroinvertebrate communities may correspond to the hierarchical arrangement of a river system. This study used scales of measurement derived from a geomorphological hierarchy to examine whether there was any congruence between the distribution of macroinvertebrate communities and the organisation of a river system at the catchment, zone, reach and riffle scales. The Upper Murrumbidgee River Catchment study area (13 005km/2) was divided into catchments, zones within catchments, reaches within zones and riffles within reaches. Macroinvertebrate collection was stratified across these scales according to a balanced nested hierarchical design, and environmental data were also collected at the catchment, zone, reach and riffle scales. Simultaneous multiscale treatment of biological and environmental data allowed identification of multiscale patterns of macroinvertebrate distribution in relation to the hierarchical organisation of a river system, as well as identification of hierarchical interactions between macroinvertebrate communities and environmental factors. Multivariate (ANOSIM, classification, ordination) and univariate (Nested ANOVA) statistical techniques were employed, and each analysis was performed at the species and family levels of taxonomy. Macroinvertebrate communities were highly similar within a reach, because this is the point in the geomorphological hierarchy where environmental conditions become more homogeneous, relative to larger scales. Conversely, communities were dissimilar at the larger zone and catchment scales because environmental conditions become more heterogeneous, relative to smaller scales. However, the reach within zone scale also represents the point where sampling reaches become distinct across the landscape, and the similarity of macroinvertebrate communities within a reach may also be related to the spatial proximity of samples. Hence, macroinvertebrate community distribution is only congruent with the smaller scales of river system organisation. Despite the lack of congruence between macroinvertebrate community distribution and the larger catchment and zone scales of river system organisation, there was a strong regional pattern of distribution in the Upper Murrumbidgee River Catchment. This regional-scale pattern self-emerges from biological information, and is larger than the geomorphologically derived catchment scale. Partitioning of macroinvertebrate data into regional groups subsequently revealed some congruence between macroinvertebrate distribution and the catchment and zone scales of river system organisation. An alternative hierarchy consisting of biological regions, biological clusters, geomorphological reaches and geomorphological riffles was marginally better able to capture patterns of macroinvertebrate distribution than the original catchment, zone, reach and riffle scales. Thus, consideration of the hierarchical organisation of stream systems from a purely physical perspective may fail to encompass scales that are relevant to biota, and biological information should be included as a primary hierarchical component of landscape-scale studies of macroinvertebrate distribution. The pattern of region and reach-scale macroinvertebrate distribution was matched by a general pattern of large catchment and local reach-scale environmental influence. This occurred despite testing of catchment, zone, reach and riffle-scale environmental variables against both the scaled and non-scale pattern of macroinvertebrate distribution. Macroinvertebrate communities were influenced by local reach-scale characteristics such as riparian vegetation character and channel morphology, but rifflescale hydrological variables were also associated with some headwater communities. However, macroinvertebrate communities also sit within a broader landscape context and are influenced by large catchment-scale factors such as landuse, or by factors indicating the geographical position of the sample or the size of the stream. The large and local-scale environmental variables that influence macroinvertebrates are related within a geomorphological hierarchy, and macroinvertebrates may respond deterministically to the same type of environmental factor expressed at different scales. These responses should not be treated as statistical correlates, but rather, they should be viewed in the context of a hierarchy of river system organisation. There was little difference in the overall scale-related findings between species and family level. Family-level macroinvertebrate communities were similar within a reach and dissimilar among reaches, zones and catchments and there was a large regionalscale pattern of family-level community distribution. Local reach-scale and large catchment-scale environmental factors were most strongly associated with family-level macroinvertebrate distribution. Replication of these scale-related findings at both levels of taxonomy indicates that aggregation from species to family level does not result in loss of ecological information pertaining to primary hierarchical patterns. However, the difference between species and family level was pronounced when tracing the hierarchical occurrence of individual taxa, in the context of theories such as the landscape filters hypothesis and habitat based model. In particular, there was a shift in the scale at which families began to be removed from the hierarchy from the region to the smaller cluster scale. This shift was related to the lowered distinctiveness of familylevel regional macroinvertebrate groups, but also suggests that environmental filters may act differently on species and families. The use of family-level data is not recommended for the testing of theories of hierarchical taxon occurrence, because these theories rely on the accurate detection of precise macroinvertebrate-environment relationships. The use of scales of measurement derived from a geomorphological hierarchy provides a process-based foundation for marrying the biological and physical domains, and for examining the hierarchical interactions that may occur between these domains. However, the results of this study indicate that overlaying the biological and physical domains is not a straightforward task, because the biological domain may be influenced by factors other than the deterministic relationship between macroinvertebrates and environmental conditions. Regardless, this study has taken some basic principles of fluvial geomorphology and incorporated them into the design of a standard stream ecology study. Given the relatively advanced state of knowledge that exists individually in the disciplines of fluvial geomorphology and stream ecology, integration and application of concepts across disciplines represents an exciting future opportunity in aquatic science.

Radioactive chromium-51, a waste byproduct from operation of nuclear reactors at Hanford, Washington, has been followed down the Columbia River and into the Pacific Ocean. Chemical factors influencing the partitioning of ⁵¹Cr between solution and sediment have been considered. Chromium-5l, in a hexavalent oxyanion when introduced into the Columbia River, largely remains in solution in a hexavalent anion during its passage through the lower river and after its entrance into the Pacific Ocean. A minor fraction of Hanford-induced ⁵¹Cr becomes attached to suspended particles and bottom sediments. Reduction of Cr(VI) to Cr(III) apparently precedes or accompanies sorption. Iron oxides appear to be the most important sorption substrate. Sediment organic matter acts both as a reducing agent, making ⁵¹Cr less soluble, and as a sorption substrate. Ion exchange on sediment particles is not important in retention of ⁵¹Cr by Columbia River sediment. Chromium-51 is a sensitive and unique tracer for Columbia River water at sea and has been used to trace the Columbia River plume up to 525 km away from the mouth of the river. Dispersion of ⁵¹Cr by the Columbia River system would be adversely affected by: 1) lowered pH; 2) presence of particulate organic wastes; 3) increased temperature; 4) increased biological oxygen demand. These factors would increase the rate of uptake of ⁵¹Cr by sediments and thus increase the steady-state inventory of ⁵¹Cr on the bottom of the river. / Graduation date: 1967

The one-dimensional numerical model developed by Carl R. Goodwin is applied to the Siuslaw estuary. Vertical displacement, horizontal velocity and flow of the water as a function of time and distance from the mouth given by the model are compared with field observations taken under different water mixing conditions in the estuary. The model is considered adequate under well mixed and partially mixed conditions, and inadequate under strongly stratified conditions. Estimations of deviations between model predictions and field observations are presented. Nomograms are constructed from model predictions of amplification factors, high water time lags, maximum flood velocities, maximum ebb velocities, low water time lags, maximum flood flows, maximum ebb flows, high slack water time lags and low slack water time lags, as a function of river flow, ocean tidal range and river mile for a range of 0 to 6000 cubic feet per second (0 to 170 cubic meters per second) of river flow, and 1 to 11 feet (0.30 to 3.35 meters) of ocean tidal range. These nomograms are considered adequate for predictive purposes during well mixed and partially mixed conditions of the estuary waters. / Graduation date: 1975

The Columbia River plume region was investigated during the period of 20 June to 3 July, 1968 by light scattering measurements and standard hydrographic station observations. The Columbia River plume was traced by the light scattering particles of the plume water. The light scattering particles are estimated to be contained in the plume water for 30 to 50 days. On the basis of the data taken in the Columbia River plume region, a conceptual model is made to describe the flow of river originated particles to the ocean water. In the distribution of the light scattering particles a northward deep current under the plume near the river mouth and a subsurface offshore flow near the bottom of the Columbia River plume are shown. / Graduation date: 1970

Graduation date: 1970

Thesis (M.S.)--University of Wisconsin -- La Crosse, 1983. / Includes bibliographical references (leaves 99-108).

Thesis (Ph. D.)--Oregon State University, 1967. / Typescript (photocopy). Includes bibliographical references (p. 99-109). Also available online.

Thesis (M.S.)--Oregon State University, 1982. / Typescript (photocopy). One map folded in pocket. Includes bibliographical references (leaves 72-78). Also available via the World Wide Web.

Thesis (Ph. D.)--Oregon State University, 1974. / Typescript (photocopy). Includes bibliographical references. Also available via the World Wide Web.

In October 1869, the fledgling Canadian federation was preparing for the transfer of Rupert's Land and the Northwestern Territory when the Métis set up a Provisional Government in order to resist what they saw as a unilateral annexation of their homeland. Although there were multiple references made to 'republicanism' during the Resistance, no scholar has ever explored whether republican conventions were actually present in political discourse in the District of Assiniboia prior to the Resistance and whether they were effectively activated during the Resistance. Working from the Cambridge School approach of discourse analysis, this thesis first identifies the conventions of democratic rhetorical republicanism, which includes positive and negative liberty, the rule of law, the mixed and balanced constitution and citizenship, which in turn involves virtue, the militia and real property. It then looks at the gradual introduction in Assiniboia of republican discourse from multiple sources, including the United States, Lower Canada, Upper Canada, Ireland, France and Great Britain and its circulation throughout several practical political struggles during the period from 1835 to 1869. In doing so, it shows that certain 'organic intellectuals' acted as 'transmission belts' of republican conventions and that institutional structures were a factor that rendered the activation of such conventions almost inevitable. By the time the Resistance took place in 1869, a more or less fully developed republican paradigm formed part of the linguistic matrix and was available to political actors in Assiniboia. Finally, the thesis shows that republican discourse was effectively mobilised by identifying fragments of republican conventions that were harnessed in various speechacts during the Resistance. It is argued that republican language was fundamental to the success of the ideological and political manoeuvres of the leaders of the Resistance as it was particularly effective both as an instrument of anti-colonialism and as a pragmatic ideal of self-government that sought to correct the iniquities of colonial government.