Estuaries are dynamic environments that are strongly affected by natural variability, as well as direct and indirect anthropogenic impacts. A better understanding of the drivers of carbon fluxes and biogeochemical variability in estuarine systems is needed, particularly with the increasing threat of ocean acidification. Morro Bay in Central California is a small nationally protected estuary, with seasonally low freshwater inputs. Since 2007, the bay has experienced a significant loss of native seagrass, Zostera marina, which is an important component of the marine ecosystem. Because seagrass photosynthesis decreases carbon dioxide and increases oxygen in the water column, the loss of seagrass has the potential to substantially change short-term carbonate chemistry and long-term carbon fluxes of an estuary. The spatial variability of carbonate chemistry was measured in Morro Bay using ship-board surveys during the low-inflow summer season and measured the temporal variability by collecting samples close to the shore from July to November. Discrete samples show an increase in total alkalinity and dissolved inorganic carbon in the mid and back bay regions, historically dominated by seagrass. Slightly lower total alkalinity and dissolved inorganic carbon were observed in the Fall season compared to the low-inflow Summer season. Analysis of the relative modification of alkalinity and dissolved inorganic carbon, paired with salinity and temperature data, contributes to an understanding of the drivers of the observed carbonate variability. This understanding may provide clues to the causes and effects of observed changes to the bay with seagrass loss. More broadly, it will inform the vulnerability of other low-inflow estuaries to future acidification and highlight the role seagrasses play in mitigating local acidification.

This report aims to study the degradation of poly(trimethylene carbonate) (PTMC) caused by the enzyme carboxylesterase in vitro. As well as to characterise polymer blends of f-BTI2g-TVTCN and poly(3-hydroxybutyric acid) as core components for organic electrochemical transistors (OETCs). This is to assess the suitability of these polymers in biodegradable biosensors. The degradation study of PTMC showed a lack of degradation in contrast to previous studies performed on the material; previous studies recorded a mass loss of between (5-8)% after two months. The cause for this discrepancy is still unknown but the evidence points to both systematic faults in the gravimetric analysis as well as random errors found in the equipment. The OECT showed that increasing the PHB fraction in the polymer blend resulted in a higher output. The most stable device consisted of a 1:6 blend of f-BTI2g-TVTCN to PHB. Fewer tests were conducted on the 1:10 blend because two devices were damaged during the experiment. The statistical impact of the smaller sample size cannot be overstated so further testing should be conducted to verify the results.

Yes / Several contributions in answering granulation challenges including the use of computer simulation and well thought out experimental analyses are being researched. Using a twin screw granulator (TSG) by design of experiments (DoE), comparisons on 1) equipment similarities i.e., continuous and 2) shear forces, are made to previous literature on continuous equipment and a Cyclomix. This study proposes that equipment specific DoE, better explains the contribution of parameters than investigating an identified parameter from the experimental findings from a specific equipment. Granule strength and structure are presented together with the contribution of process parameters, speed, temperature, and binder content. Seeded structures are present in all but the Extrudomix. Longer residence times within the Cyclomix facilitates seeded structures. Granule crushing strengths are higher in TSG than all other continuous equipment. Optimum condition for the formation of stronger granules with least variation is around 65.4 °C. / The authors would like to acknowledge the support from the CCIP grant (Collaboration, Capacity and IP Development) fund from the University of Bradford for ordering cunsumables and equipment.

The Proterozoic Espanola Formation (Huronian Sequence) was studied at Geneva Lake, Ontario, 45 miles north-west of Sudbury. A major lithological change exists in the Espanola Formation between this area and the type section on the north shore of Lake Huron, 75 miles to the south. Unusually pure (95 percent) microcrystalline limestones and dolostones occur in almost equal abundance to the calcareous siltstones which are the characteristic lithology of the formation in its type section. The existence and position of a fine grained deposit such as the Espanola in a stratigraphic sequence which consists mostly of glacial and periglacial deposits is unusual. It is suggested that this fine-grained deposit was an integral part of a cycle of deposition resulting from glacial advance and retreat and that its sedimentary basin was created by marine transgression in response to a glacial retreat. Spatial distribution of the Espanola Formation suggests that its sedimentary basin may have consisted of at least three environmental zones. At least one of these zones may represent a glacial melt-water lake. A microfossil search was carried out with negative results. This made speculation necessary in determining the origin of the calcareous fraction of the Espanola Formation. A mechanism is suggested whereby calcium carbonate is precipitated inorganically, as a result of photosynthesis by anaerobic bacteria. This mechanism can be observed in the present. If it is true, then the Espanola Formation may represent a time marker for the first presence of free oxygen in the atmosphere. / Thesis / Bachelor of Science (BSc)

Missing page 48 / <p> The low ambient air temperatures, together with the low annual rainfall and complete lack of vegetation in the Canadian High Arctic, results in a breakdown of the carbonate rock material by mechanical means. The importance of chemical decomposition, soil formation and transport of ionic material in solution is negligible, when compared with the role played by these same processes in more temperate climates. </p> <p> The purpose of this thesis is to investigate certain aspects of the alkali, alkaline earth and heavy metal geochemistry of selected components of the weathering cycle. The discussion will deal with concentration levels of these parameters in stream waters and, to a lesser extent, soils and stream sediments. </p> <p> Analytical results show that element distributions in the streams resemble those of more temperate carbonate terrains. However, the solute levels are, in general, lower, indicating that a greater proportion of the metals is travelling in colloidal form and/or adsorbed to slit-sized material carried by the streams. </p> <p> These findings confirm the belief that chemical weathering and transport in solution are of little importance in the area studied. </p> / Thesis / Bachelor of Science (BSc)

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