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The area of secondarily salinized lands is increasing at a faster rate over time. Many irrigation districts around the world are shrinking as a result of secondarily salinized soils. This is resulting in crop yield losses. Irrigation practices with low drainage are intensifying this problem. Bioremediation of salinized soils with halophytes is one of the means of reversing this process. In these studies, we tested the growth and performance of four salt tolerant halophytes to varying levels of salinity. We analyzed the salt content of the plant tissues at different salinities, in order to determine how the plants' tissues reflect the increases in salinity. It was discovered that Allenrolfea occidentalis tolerates and grows well at higher salinities than the other plants tested. Furthermore, the concentration of salt in the aerial plant tissue was high and increased further in response to the external salt concentration. Halophytes such as A. occidentalis can be used to remediate abandoned salt affected lands and their biomass can have an added economic value. On the other hand, domestication of wild halophytes for agronomic purposes represents another opportunity to address the increasingly salinized soils and shortages of freshwater around the world. In these studies, we assessed the potential for improvement of an oilseed halophyte, Salicornia bigelovii, through selective breeding. We compared plant characteristics of S. bigelovii cultivars produced in breeding programs with wild germplasm in a green house common garden experiment. We concluded that S. bigelovii has sufficient genetic diversity among wild accessions and cultivars to support a crop improvement program to introduce desirable agronomic characteristics into this wild halophyte.

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Many factors such as rift history, crustal structure and distribution of high thermal conductivity salt bodies throughout the sediment pile affect the present day thermal structure of the deepwater Scotian Slope. Understanding the basin's thermal evolution is crucial in determining the hydrocarbon maturation potential of this deepwater frontier basin. The Late Jurassic Verrill Canyon Formation of the deepwater slope has been inferred as the primary source rock interval for the Scotian Basin. However, to date, only twelve boreholes have sampled the Scotian Slope, and of these, none penetrate beneath the uppermost Jurassic sediments. Therefore, the distribution and maturation of deeper source rock intervals through standard vitrinite reflectance analysis remains unknown. In this study we attempt to better constrain the thermal history and maturation potential of the central Scotian Slope using a combination of recently acquired seafloor heat flow data, 2D seismic reflection data, available well data, simple lithospheric rift models and 3D thermal and petroleum systems modelling. We have derived a method of combining seafloor heat flow data with simple lithospheric rift models to provide first order constraints on the hydrocarbon maturation potential of frontier basins in dynamic 3D thermal models for regions lacking vitrinite reflectance and temperature data from boreholes. In July 2008, 47 seafloor heat flow measurements were acquired across the central Scotian Slope in an attempt to better constrain the region's thermal structure. Locations seaward of the salt diapiric province, thus unaffected by the high thermal conductivity of salt, recorded seafloor heat flow values of ~41-46 mWm-2. Significant increases in seafloor heat flow were noted for stations overlying salt diapiric structures, reaching values upwards of 72 mWm-2. The seafloor heat flow data have been corrected to remove the conductive effects of salt and the cooling effects of seafloor sedimentation on measured heat flow. The corrected data are compared with basal heat flux predictions from simple lithospheric rift models as constrained using crustal ( ) and lithospheric ( ) stretching factors after Wu (2007) to constrain heat flux history through time. Seafloor heat flow and simple modelling results suggest present day basal heat flux does not vary significantly across the slope. Present day basal heat flux across the central Scotian Slope is ~44-46 mWm-2. Basal heat flux curves from simple lithospheric rift models are used to constrain the heat flux history in 3D thermal and petroleum systems models of the central Scotian Slope. Numerous basal heat flux histories were tested to determine which heat flux history yielded the best match between modelled and measured seafloor heat flow data and to determine how varying basal heat flux affects the modelled hydrocarbon maturation of Verrill Canyon source rocks. The basal heat flux history which yielded the best match to measured seafloor heat flow data suggests that the Late Jurassic source rock interval rests primarily within the late oil window. Variations in radiogenic heat production across the margin associated with thickening continental crust were tested and suggest that significant variations in both maturation and seafloor heat flow may occur if radiogenic heat producing elements occur in high enough concentrations in the crust.

This thesis investigated the perception of salt taste in two novel strategies for inclusion of NaCl in liquid foods: water-in-oil (w/o) emulsions and mucoadhesive biopolymer solutions. The major factors influencing w/o emulsion stability and perception were evaluated and a response surface model was developed. The amount of dispersed aqueous phase was the most significant factor affecting stability and perception. NaCl stabilized the emulsions and depressed salt sensory perception at elevated concentrations due to its interaction with the emulsifier polyglycerol polyricinoleate. Future research should elaborate events during oral processing of w/o emulsions. Biopolymer mucoadhesive character and concentration effects were also investigated. Mucoadhesion did not enhance salt taste. Above c*, there was a significant depression of sensory intensity, enhanced in polymers with hyperentanglements in solution. The depressive concentration effect may mask the effects of mucoadhesion. Future research should also inspect the influence of thickened hydrocolloid microstructure on perception. / The Advanced Foods and Materials Network

De-icing agents such as road salts is one of the most commonly used winter road management strategies employed in Canada and the United States. However, the use of chloride has caused negative impacts on aquatic habitats and drinking water supplies. The purpose of this study is to develop a methodology using readily available GIS data to identify salt vulnerable areas, through evaluating the impact the application of road salts have on areas of interest and quantifying the vulnerability to the area in order to prioritize implementation of best management practices. The proposed methodology for assigning a vulnerability score to a given watershed has been divided into two receiving receptors; surface water and groundwater recharge. The methodology employs a chloride mass balance approach. The vulnerability assessment was performed on seven sites in four watersheds in the Greater Toronto Area and validated using Hanlon Creek watershed in Guelph, ON.

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No description available.

This study was undertaken to investigate mobile salt and its effect on fault structures and gas hydrate occurrence in the northwestern Gulf of Mexico. Industry 2-D multichannel seismic data were used to investigate the effects of the salt within an area of 7,577 mi^2 (19,825 km^2) on the Texas continental slope in the northwestern Gulf of Mexico. The western half of the study area is characterized by a thick sedimentary wedge and isolated salt diapirs whereas the eastern half is characterized by a massive and nearly continuous salt sheet topped by a thin sedimentary section. This difference in salt characteristics marks the edge of the continuous salt sheets of the central Gulf of Mexico and is likely a result of westward decline of original salt volume. Beneath the sedimentary wedge in the western part of the survey, an anomalous sedimentary package was found, that is described here as the diapiric, gassy sediment package (DGSP). The DGSP is highly folded at the top and is marked by tall, diapiric features. It may be either deformed shale or the toe of a complex thrust zone detaching the sedimentary wedge from deeper layers. The dataset was searched for the occurrence of bottom simulating reflectors (BSRs), as they are widely accepted as a geophysical indicator of gas trapped beneath gas hydrate deposits, which are known to occur farther east in the Gulf. Although, many seismic signatures were found that suggest widespread occurrence of gas within the upper sediment column, few BSRs were found. Even considering non-traditional definitions of BSRs, only a few occurrences of patchy and isolated BSRs features were identified. The lack of traditional BSRs is likely the result of geologic conditions that make it difficult to recognize gas hydrate deposits. These factors include: (1) unfavorable layer geometries, (2) flow of warm brines from depth, (3) elevated geotherms due to the thermogenic properties of salt and its varying thickness, and (4) widespread low porosity and permeability sediments within the gas hydrate stability zone.

The World Health Organization (WHO) states that iron deficiency (ID) is the preeminent global micronutrient deficiency. Maternal ID is linked to cardiovascular disease and hypertension in offspring, and yet the impact of ID on the kidney is not known. We characterized the impact of ID on circulating and tissue levels of iron and renal function. Seven and ten week old male and female Wistar rats were fed either control (270ppm) or low iron (3ppm) diet for ten weeks. Total, non-heme and heme iron levels in liver, kidney cortex and kidney medulla were measured following the dietary period. Hematocrit decreased most in males regardless of age (Male 7-17wk: 47%→ 31%; 10-20wk: 47%→ 33.5%; Female 7-17wk: 47%→ 34%; 10-20wk: 47%→ 39%). Dietary ID markedly decreased liver and kidney cortex non-heme iron in both males and females (Female: liver-178±25 to 21±7 ppm; kidney cortex-51±9 ppm to 10±1 ppm; Male: liver-102±18 ppm to 11±1 ppm; kidney cortex 36±14 to 15±8 ppm). In contrast, non-heme iron in the kidney medulla was not significantly decreased Secondly, in order to determine the impact of ID on renal function, blood pressure was monitored using radio-telemetry starting at six weeks of age (~175g body weight). Dietary salt challenge (5 days Low5 days HighNormal) was administered to all animals (n=16) starting at eight weeks of age. At ten weeks rats were assigned to either control (225pm) or low (3ppm) iron diet. Dietary salt challenge was repeated at 13 and 18 weeks of age respectively. Despite significant lowering of hematocrit (Control 45%  Low iron 38.6%) hemodynamic changes were minimal, in that, although blood pressure was lowered following ten weeks of dietary iron restriction, blood pressure did not change in response to dietary salt (Control MAP:105.0 ± 2.5mmHg; ID MAP:100.6 ± 3.2mmHg ). Collectively the tissue and functional analyses demonstrate that the body adapts to lowering of tissue iron supply with ID. The relative sparing of non-heme iron in the kidney medulla suggests that iron in this region of the kidney may be spared because of its importance in the systems responsible for regulating fluid and sodium balance. / Thesis (Master, Pharmacology & Toxicology) -- Queen's University, 2007-07-18 12:00:09.853