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Fine substrate sediments are considered to be important in the management of urban river systems. Urban construction activities have been reported to increase sediment loads causing the temporary siltation of channel substrates within the urban area. Nevertheless fine sediment derived from urban areas frequently carry toxic material well in excess of background concentration levels. While the soluble phase of heavy metals and the importance of their association with suspended sediment has received considerable attention, longer term studies of fine urban river-bed sediments are limited. Furthermore studies of heavy pollutants in active stream sediments, below mine waste tips, have shown the channel substrate can provide a long term store for heavy metals in association with fine sediments. This thesis investigates the variety of impacts that urbanisation has upon the sedimentation of gravel bed rivers. A freeze coring technique and infIltration baskets have been used to study the textural-geochemical properties of fme matrix sediment and its development within an urban river-bed framework, within and below a number of contrasting urban catchments in the U.K. Complex urban hydrological and sedimentological regimes are shown to have a variable influence upon matrix sedimentation. The actual volume of matrix present within the urbanised substrate is influenced by the degree of urbanisation within the catchment. Furthermore this sediment is finer in size and associated heavy metal concentrations are well in excess of natural background levels. Although heavy metal levels do correlate slightly with textural characteristics, the presence of maximum concentrations at depth in the substrate indicate possible mobilisation of metals within the urbanised river-bed. The temporal behaviour of matrix development within an urbanised substrate is shown to differ from natural river-beds. Despite high suspended sediment concentrations the magnitude of the potential rate of supply is lower, by 50 percent, and dominated by organic material. This sediment also contains elevated heavy metal cocnentrations. This contrasts to the inorganic sediment ingress of natural river substrates. It is concluded that fine matrix sediments within urban gravel bed rivers should be at least of concern to public health engineers, water authorities and conservationists.

This thesis explores in what ways Kemi River dwellers in the Finnish province of Lapland use and have used the waters of their home river, and how their skills and experiences are reflected in their conceptualisation of the riverine world. Based on a year of ethnographic fieldwork, I portray river dwellers’ relations with the Kemi, focusing on practices and narratives and how the flow of water and other matter figures in them.  Having undergone radical transformation over the course of people’s lives, the river is tightly interwoven with personal biographies. An environmental history reveals how people and stream have mutually shaped each other for a long time and continue to do so today. I focus on three activities, fishing, transport, and hydroelectricity generation.  Fishing, formerly the major political-economic river use but economically marginal today, continues to provide a significant way of engaging with and coming to know the river. Boating has radically changed with damming, mechanisation and the displacement of travel and transport to the roads, and presently constitutes a way of performing one’s belonging to the Kemi, in tems of both “understanding” its waters and claiming them politically.  Similarly, timber transport has recently shifted from the river to the roads, though the memories of large-scale floating operations are still prominent in river dwellers’ stories and the riverine landscape.  Finally, hydroelectricity infrastructure widely transformed the river dwellers’ world and introduced a powerful technology negotiating water flows, electricity markets and inhabitants’ sensibilities. Scrutinising these practices and narratives reveals profoundly rhythmic patterns in the river dwellers’ activities, the river’s dynamics and the world around. Life on the river emerges as the ongoing articulation of these manifold rhythms, shaping and being shaped by their interaction.

A limited amount of research has been done to investigate the factors influencing algal abundance in large river systems. This study examines light as the primary factor that controls algal abundance in the Upper Mississippi, Missouri and Ohio Rivers. Data were collected for 2004 in conjunction with the Environmental Monitoring Assessment Program- Great River Ecosystems EMAP-GRE project using EPA approved methods. Chlorophyll a concentrations were 34.6 µg•L-1 in the Upper Mississippi, 19.8 µg•L-1 in Missouri River and 9 µg•L-1 in the Ohio River for 2004. Chlorophyll a concentrations were significantly different among the three rivers (p<0.0001) but not between years. Inter-river variation could be loosely correlated with light availability: mean Average Irradiance Dosages, which consider factors that affect light climate (depth, transparency, velocity, surface irradiance), by river corresponded with mean chlorophyll a levels by river. Intra-river variation seemed to be due to both the influence of light and nutrients.

Thesis advisor: Noah P. Snyder / Estimating annual phosphorus (P) loading in impaired fresh water bodies is necessary to identify and prioritize management activities. A variety of monitoring programs and water quality models have been developed to estimate P loading in impaired watersheds. However, uncertainty associated with annual riverine P loads tends to receive less attention. This study addresses this gap by exploring the range in annual total phosphorus (TP) loads from two common load estimation methods using data collected in the Charles River watershed (CRW) in eastern Massachusetts. The CRW has two P Total Maximum Daily Load (TMDL) reports due to impairments with respect to excessive summer algal growth. Three estimation methods are used in this thesis to quantify annual TP loads (LY): the concentration-discharge relationship (CQ), the land use coefficient (LUC) method, and the average concentration, continuous discharge (ACQ) method. LY derived using the LUC method spanned an average relative percent range of 214% at each site, whereas LY results from the concentration-discharge method spanned an average relative percent range of 56%. While results of the CQ method produced a narrower range of LY, the CQ relationship is subject to seasonal dependencies and inconsistency through time. Seasonal terms in the LOADEST program, a publicly available and commonly used statistics tool, do allow the model estimates to capture trends through time, an advantage over the LUC method. Results of an interlaboratory comparison of P concentrations demonstrate the potentially large role of analytical uncertainty in LY estimation. Significant discrepancies between the results of each method for a single location and time suggest that loading estimates and consequently management priorities may be dependent on the estimation technique employed. / Thesis (MS) — Boston College, 2018. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Earth and Environmental Sciences.

Thesis (M.S.V.S.)--Massachusetts Institute of Technology, Dept. of Architecture, 1979. / by Robb Moss. / Thesis (M.S.V.S.)--Massachusetts Institute of Technology, Dept. of Architecture, 1979.

Thesis (M.B.A.)--Boston University