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28 pp. / Arizona Watershed Stewardship Guide / Stream Processes for Watershed Stewards describes the basic concepts, processes and features of streams in Arizona and in general. The is designed as a tool for land owners, managers, and others to learn about the physical, chemical and biological attributes of streams as they evolve. These concepts can then be applied to better stream management.

A tilting bed flume study was made to examine the relationships between velocity, suspended sediment and infiltration rate in alluvial channels for velocities from 2 to 5 feet per second and suspended sediment up to 0.6 percent. Preliminary experiments using samples from Rhllito Creek near Tucson, Arizona to define limits for the flume study included mechanical analyses of bed sediments, permeability and infiltration tests, and analyses of suspended sediment in flood waters. Flume experiments using bed materials from Rillito Creek were made with constant velocity and variable suspended sediment content, then with constant suspended sediment and variable velocity. Considerable variability was found in the mechanical analyses, permeability and infiltration tests, and suspended sediment content for samples from different locations. The flume studies indicated a direct relationship between velocity and infiltration rate and an inverse relationship between the suspended sediment content and infiltration rate in the ranges tested. Very poor correlation was found between the preliminary permeability and infiltration tests and the flume infiltration rates, but good correlation was obtained for the flume results with the flow losses and natural recharge occurring in the river channels in the Tucson area.

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This thesis investigates the influence of bed material shape on sediment transport in gravel-bed rivers. The approach involves a combined series of field and laboratory experiments. Magnetic tracing experiments were carried out at three experimental sites in two Pennine gravel-bed streams. The specific aim of these experiments was to quantify the selective transport of different shapes of coarse river gravel and determine their spatial sorting within a natural stream channel. A total of 900 tracers in three size groups (32- 64 mm, 64-128 mm and greater than 128 mm) and four shape classes (spheres, blades, rod and discs) were prepared for each of the three sites. In die laboratory, tilting table experiments were carried out to clarify the mechanistic behaviour of different particle shapes, sizes and orientations on a variety of artificial and naturally formed bed roughnesses. Using strobe-light photography visualization experiments were undertaken with natural and artificially-moulded gravel-size particles of differing shape, size and weight in order to investigate the influence of shape on settling, grain impact, initial motion and transport paths of gravel-size particles. Results of the magnetic tracing experiments showed that there was both size and shape selectivity in bedload transport. Preferential movement occurred in die small and medium particle size classes with tracers concentrated along the channel thalweg. Sphere-shaped particles were transported the greatest distance and in greatest numbers. Rods also moved preferentially, while discs showed a lesser degree of transport and blades hardly moved at all. Results from the tilting table experiments highlight the importance of roundness as well as particle form and particle orientation in continuing thresholds of entertainment. In terms of size, friction angle was found to depend on the ratio of the diameter of the test particle to be moved to that it rests upon (d/D). Shape and orientation were found to be important parameters influencing friction angles. On a given bed roughness and for a constant size non-spherical test particles showed greater friction angles than spherical ones. A very clear difference was found in friction angle distibutions between sphere, transverse rod and other flat-shaped particles, namely, blades with parallel and transverse orientations, disc, and rod with parallel orientations. Visualisation experiments indicated that shape is an important particle characteristic that has a significant effect on settling rates and also the mode of near bed transport. These effects increase with greater particle sizes. The departure of a particle from a sphere leads to a decrease in its settling velocity, Experiments, across a range of test sizes showed that when compared to a sphere of equivalent weight and density, sphere and rod-shaped particles tend to settle the fastest and move by rolling. Discs and blades showed slower settling rates and, in most instances, moved by sliding. Experiments carried out with irregularly-shaped, natural particles show greater variability in settling behaviour and irregular patterns of motion. For every size group, sphere and rod shaped particles have lower critical angles of initial motion flian blade and disc-shapes. Regardless of shape, greater bed roughness, or decreasing particle size results in an increase in the critical angle for motion.

The presence and configuration of subglacial water and sediment maintain the fast flow of arterial ice streams in Antarctica and airborne ice-penetrating radar data represent a potential resource of information about the ice-bed interface. In this thesis an original contribution to the exploration of Antarctic subglacial environments is made through the analysis of airborne surveys from Evans, Institute and Möller Ice Streams, West Antarctica. The primary approach employed is the derivation of bed-returned power (BRP), a proxy for ice-bed reflectivity, which is strongly influenced by the presence of liquid water. Estimating radar englacial attenuation (EA) accurately is a critical part of BRP analysis and a modelled approach is primarily used. BRP is derived across Evans Ice Stream and shows large-scale patterns relating to hypothesised hydrological and geological contrasts at the ice-bed. These results are developed to investigate the influence of: (1) adopted EA correction; (2) the influence of assigned ice dielectric properties in modelled EA; (3) subglacial roughness and (4) the spatial scale over which BRP is derived. Some areas of high basal drag can be detected with BRP analysis, indicating that variations in subglacial hydrology are responsible for their existence. The widely-used empirical method of estimating EA by relating ice thickness to uncorrected BRP is shown to be unreliable where ice properties change along a transect. Monte Carlo error analysis of modelled EA shows that poorly constrained ice dielectric properties also result in significant BRP uncertainty. BRP beneath Institute and Möller Ice Streams is derived on catchment- and local-scales over hypothesised subglacial features. Bungenstock Ice Rise is marked with a clear BRP signal but the locations of "active" lakes, as delineated by satellite altimetry, do not. The sensitivity of idealised flow paths to surface change and grid size are investigated. Potential future research directions regarding BRP analysis are discussed.

Nessa dissertação relatam-se e discutem-se resultados obtidos durante as ações de uma tentativa para mostrar que: o estudo sobre alguns métodos usuais para análise de relações entre conseqüências de construção e operação de rodovias com o meio ambiente pode contribuir para identificar informações úteis para orientar atividades que, do ponto de vista de habitantes nativos, são necessárias para proteção e manutenção de igarapés em \"regiões de quase nenhum desenvolvimento\". / Some results obtained in this dissertation was reported and discussed in trying to show that the consequences of studies about some usual methods aiming to analyze the relationship among construction, operation and maintenance of highways into the environment should contribute to identify useful information and lead necessary activities (from the native inhabitants point of view) to protect and maintain the \"stream\" in regions with lack of development.

Nessa dissertação relatam-se e discutem-se resultados obtidos durante as ações de uma tentativa para mostrar que: o estudo sobre alguns métodos usuais para análise de relações entre conseqüências de construção e operação de rodovias com o meio ambiente pode contribuir para identificar informações úteis para orientar atividades que, do ponto de vista de habitantes nativos, são necessárias para proteção e manutenção de igarapés em \"regiões de quase nenhum desenvolvimento\". / Some results obtained in this dissertation was reported and discussed in trying to show that the consequences of studies about some usual methods aiming to analyze the relationship among construction, operation and maintenance of highways into the environment should contribute to identify useful information and lead necessary activities (from the native inhabitants point of view) to protect and maintain the \"stream\" in regions with lack of development.

Aluminium (Al) has been recognised as a main toxic factor alongside pH in acidified water ecosystems. The toxic effect of Al has been attributed to inorganic Al (Ali), though there are few in situ studies in ambient humic waters which are the focus of this thesis. The aim was to estimate Ali toxicity and thus also Ali concentrations in Swedish humic streams. Subsequently it is necessary to analyse Ali correctly, which was studied by modelling and method intercalibrations. The hypothesis was that the effect of Ali could be followed via physiological effects and Al accumulation, as well as by mortality. Toxicity was studied by in stream exposures of brown trout (Salmo trutta L.) and two salmonid prey organisms (Gammarus pulex and Baetis rhodani) during spring flood. The modelling of the Ali fraction was performed using monitoring data covering all of Sweden with satisfactory results. The essential variables for Ali modelling were determined; Al, DOC, pH and F, while Fe, Ca and Mg had less effect. The automated analytical procedure for Ali (with cation exchange followed by complexation with pyrocatechol violet) was modified and validated and showed to be the preferred method for laboratory analyses. To avoid detrimental effects for brown trout Ali should be <20 µg/L and pH >5.0; mortality was high when the Ali was above 50 µg/L. The invertebrates were more sensitive, as mortalities occurred at pH <6.0 and Ali >15 µg/L for G. pulex, and at pH <5.7 and Ali >20 µg/L for B. rhodani. It is prudent to use a wide view and let the most sensitive species set the tolerance limits; a pH above 5.7-6.0 and Ali below 15-20 µg/L allows the stream ecosystems to thrive. Today, as waters are recovering from acidification, the aim of mitigating liming is to carefully adjust dosage to avoid suboptimal water quality. The thresholds found in this thesis can be used to efficiently but carefully decrease liming, as both Ali and pH levels have to be balanced to sustain the recovering aquatic biota.

The concept of integration of industries in urban setup is the current trend among researchers and engineers in the field of industrial ecology and environmental engineering. Trend of urbanization forces an increasing human demand for energy, materials, water and other resources. Urban symbiosis nowadays is closely related to the controlling of urban metabolism. Closing material loops works as an effective way for a circular economy where theoretically no waste is generated. In this thesis work, an investigation has been made for studying current symbiotic activities in the city of Linköping and look for any potential energy or by-product synergies from industrial activities and the urban waste streams. Some of the companies have been found to be already engaged in such type of activities, directly or indirectly. Hence, uncovering symbiotic activity is also an important task to consider while assessing the feasibility of a network of industries and urban settlement. Finally, it is concluded that the symbiotic activity in the city of Linköping is developing with discovering of new opportunities from waste and by-products from industries and the city area.  The municipal utility company Tekniska Verken and its subsidiary Svensk Biogas could play the role as anchor tenants and the aeronautics company SAAB, for its huge production line, has good potential to participate in exchange of physical materials.