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This thesis was designed to quantify absorbance and fluorescence characteristics of dissolved organic matter (DOM) in North Atlantic, Pacific and Arctic Oceans. DOM was described in water masses of distinct sources and formation pathways as well as in regions where environmental forcings such as deep water upwelling, enhanced biological activity and receipt of freshwater discharge were prevalent. Influence of sea ice on DOM in Beaufort Sea mixed layer (0 to 30 m) seawater was investigated based on sea ice extent as well as freshwater fractions of meteoric (f_mw) and sea ice melt water (f_sim) calculated from oxygen isotope ratio (δ18O). The effect of DOM exposure to simulated solar radiation was also assessed to determine the resilience of fluorescent fractions of DOM to photodegradation. This research aims to further our ability to trace DOM in marine environments and better understand its transformation pathways and predict its fate as part of the oceanic carbon cycle in a changing climate.

Author Keywords: Absorbance, Arctic Ocean, Dissolved organic matter, Fluorescence, Parallel Factor Analysis, Sea Ice

Introduced as part of the Canada-Ontario Immigration Agreement, Local Immigration Partnerships (LIPs) mark a fundamental shift in local settlement policy. To address the gap in knowledge about the implications of this policy change, this thesis research features a case study of Durham Region's LIP. Objectives were designed to examine the impact of Durham's LIP by interviewing 52 key-informants within six sectors involved in settlement and integration. Findings indicate an effective application of the LIP policy with participants pointing to the LIP's vital role in bringing Welcome Centres to Durham, increasing the attention and profile of immigration issues and improving governance relations amongst different sectors in settlement and integration. A product of local circumstances, the LIP has engaged in a quasi-advocacy role educating mainstream service providers and institutions on how to respond to a diversifying population. Results contribute to the relatively under-studied but growing knowledge of the LIP policy while demonstrating that the localization of immigration policy under the appropriate terms can be successful.

Author Keywords: Governance, Integration, Local Immigration Partnerships, Ontario, Regionalization, Settlement

This thesis reports on the 2010 excavations of the North Group and Eastern Court at the ancient Lowland Maya site of Pacbitun. It provides a construction history of the architecture and an analysis of associated artifacts, burials, and caches. The archaeological investigations demonstrate that the seven structures (Strs. 34-40) of this restricted access plazuela group were built in the Early Classic period, and renewed in the Late Classic period. Based on analyses of artifacts (ceramics and lithics), skeletal and faunal remains, and intra- and inter-site comparisons, the North Group functioned as a secondary elite domestic residential group. Reconstruction suggests that the inhabitants here were not commoners; instead, the occupants probably were related to the ruling elite of Pacbitun. Some of the evidence includes the central location and elevation of the North Group, the presence of red painted plaster surfacing, a burial with multiple ceramic musical instruments, and multiple dedicatory caches with exotic goods (e.g., marine shell, jadeite, "Charlie Chaplin" figures).

Author Keywords: Ancient Maya, ceramic musical instruments, Charlie Chaplin figurines, Pacbitun, North Group, Eastern Court, Belize River Valley, Belize, restrictive access plazuela group, secondary elite

This thesis examines the mobilization of labour required for fortification construction during the Late Helladic (LH) period of the Aegean Bronze Age. It adopts an "energetics" approach to architecture, as a framework for systematically calculating the labour costs of construction, and using such costs to infer relative differences in political power among groups and communities through the implied differences in labour control. Accordingly, construction costs were generated for thirty-six LH fortifications, located across seven distinct regional zones of the Greek mainland and Aegean Sea. These values were then compared and evaluated against what is known of the political geographies for each region, to measure the extent to which the mobilization of labour was a function of regional power in Late Bronze Age Greece. These assessments revealed that a wide range of variation existed among the sampled regions in terms of the strength and nature of this connection, underscoring the diversity in labour relations that developed throughout the Aegean during the LH period. The labour costs were also used to suggest specific systems of recruitment that may have been in place for mobilizing workers, and to argue that fortification construction would not have been particularly burdensome or demanding for certain local populations.

Author Keywords: Energetics, Fortifications, Late Bronze Age, Monumental Architecture

The objective of this thesis is to better understand the demography and habitat selection of Newfoundland caribou. Chapter 1 provides a general introduction of elements of population ecology and behavioural ecology discussed in the thesis. In Chapter 2, I examine the causes of long-term fluctuations among caribou herds. My findings indicate that winter severity and density-dependent degradation of summer range quality offer partial explanations for the observed patterns of population change. In Chapter 3, I investigate the influence of climate, predation and density-dependence on cause-specific neonate survival. I found that when caribou populations are in a period of increase, predation from coyotes and bears is most strongly influenced by the abiotic conditions that precede calving. However, when populations begin to decline, weather conditions during calving also influenced survival. I build on this analysis in Chapter 4 by determining the influence of climate change on the interplay between predation risk and neonate survival. I found that the relative equilibrium between bears and coyotes may not persist in the future as risk from coyotes could increase due to climate change. In Chapter 5, I investigate the relationships in niche overlap between caribou and their predators and how this may influence differential predation risk by affecting encounter rates. For coyotes, seasonal changes in niche overlap mirrored variation in caribou calf risk, but had less association with the rate of encounter with calves. In contrast, changes in niche overlap during the calving season for black bears had little association with these parameters. In Chapter 6, I examine broad-level habitat selection of caribou to study trade-offs between predator avoidance and foraging during the calving season. The results suggest that caribou movements are oriented towards increased access to foraging and the reduction of encounter risk with bears, and to a lesser extent, coyotes. Finally, I synthesize the major findings from this thesis and their relevance to caribou conservation in Chapter 7, to infer that Newfoundland caribou decline is ultimately driven by extrinsic and intrinsic elements related to density-dependence. Reduction in neonate survival emerged from nutritionally-stressed caribou females producing calves with lower survival.

Author Keywords: Behavioural ecology, Black bear (Ursus americanus), Coyote (Canis latrans), Population ecology, Predator-prey interactions, Woodland caribou (Rangifer tarandus)

The purpose of this study was to quantify the variation of baseline carbon and nitrogen stable isotope signatures in the Lake Simcoe watershed and relate that variation to various physicochemical parameters. Particulate organic matter samples from 2009 and 2011 were used as representatives of baseline isotopic values. Temporal data from two offshore lake stations revealed that δ15N of POM was lowest mid-summer and highest after the fall turnover. POM δ13C was variable throughout the summer before declining after fall turnover. Spatial data from the lake and the tributaries revealed that POM stable isotope signatures were highly variable. Various physicochemical parameters indicative of phytoplankton biomass were significantly positively correlated with POM δ15N and significantly negatively correlated with POM δ13C. The correlations were mostly significant in the tributaries, not the lake. Moreover, many of the correlations involving δ15N of POM were driven by extreme values in Cook's Bay and its tributaries. In general, it's likely that different processes or combination of processes were affecting the δ15N and δ13C POM in the Lake Simcoe watershed as physicochemical parameters alone could not explain the variability. Measuring the δ15N of ammonium and nitrate, as well as the δ13C of DIC would help discern the dominant nitrogen and inorganic carbon cycling processes occurring in the Lake Simcoe watershed.

Author Keywords: δ13C, δ15N, isotopic baseline, particulate organic matter, spatial variation, stable isotopes

Effective population size (Ne) is a key concept in population genetics, evolutionary biology and conservation biology that describes an important facet of genetic diversity and the capacity of populations to respond to future evolutionary pressures. The importance of Ne in management and conservation of wild populations encouraged the development of numerous genetic estimators which rely on a variety of methods. Despite the number and diversity of available Ne methods, however, tests of estimator performance have largely relied on simulations, with relatively few tests based on empirical data. I used well-studied wild populations of brook trout (Salvelinus fontinalis) in Algonquin Park, Ontario as a model system to assess the comparative performance of multiple Ne estimation methods and programs, comparing the resultant Ne estimates against demographic population size estimates.

As a first step, the genetic diversity and ancestry of wild brook trout populations was determined using 14 microsatellite loci. Genetic structure of brook trout populations showed variable contributions from historical supplemental stocking and also identified localized gene pools within and between watersheds, reflecting variable levels of connectivity and gene flow. Once the genetic ancestry and connectivity of populations had been resolved, single sample (point) and two samples (temporal) genetic estimators were used to estimate Ne of populations with pure native ancestry. Values obtained from genetic estimators utilizing both methods were variable within as well as among populations. Single sample (point) estimators were variable within individual populations, but substantially less than was observed among the temporal methods. The ratios of Ne to the estimated demographic population size (N) in small populations were substantially higher than in larger populations. Variation among estimates obtained from the different methods reflects varying assumptions that underlay the estimation algorithms. This research further investigated the effect of sampling effort and number of microsatellite loci used on Ne values obtained using the linkage disequilibrium (LD) estimation method. Ne estimates varied substantially among values generated from subsets of loci and genotyped individuals, highlighting the necessity for proper sampling design for efforts aiming to measure Ne. Despite the variation observed among and within estimation methods, the Ne concept is a valuable for the conservation and management of both exploited and endangered species.

Author Keywords: Brook Trout, Effective population size, Genetic Diversity, Genetic Structure

ABSTRACT

Calving site selection and fidelity in a restored elk (Cervus elaphus) herd in Bancroft

Ontario, Canada.

Michael R. Allan

Parturition site selection by ungulates is believed to be influenced by forage abundance and concealment from predators. In 2011 and 2012, I used vaginal implant transmitters and movements to identify calving sites for 23 GPS collared elk (Cervus elaphus) from a restored herd. I tested the hypothesis that maternal elk used sites with higher forage and denser concealment compared to pre-calving sites at micro and macrohabitat levels. I detected no significant microhabitat differences from direct measurements of vegetation. At the macrohabitat scale, based on proximity of landcover classes, mean distances to hardwood forests was significantly less for calving (153 m) than pre-calving sites (198 m).

Site fidelity is hypothesized to offer security in terms of familiarity to an area. I tested the hypothesis that females demonstrated fidelity to their previous year's location during pre-partum, parturition, post partum, breeding and winter periods. Elk were more philopatric during parturition and post partum than during breeding. Compared to winter elk were more philopatric during pre-partum, parturition and post-partum periods. Expressed as distance between consecutive-year calving locations, site fidelity varied with 27% of females exhibiting high (<1 km), 18% moderate and 55% (>2.9 km) low fidelity.

I measured nearest-neighbour distances at calving time, exploring the hypothesis that females distance themselves from conspecifics. Elk increased the average distances

to collared conspecifics during parturition; however, sample sizes were small. This strategy might influence calving site selection.

Rapid movement prior to parturition, low site fidelity and spacing-out of females during parturition appear to be strategies to minimize predator risk and detection. Little evidence of selection for vegetation structure suggests this may not be limiting to these elk.

Author Keywords: calving, elk, fidelity, movement, parturition, selection

This study investigated the role of the JNK signaling pathway in cadmium-treated mouse embryo forelimb bud cells in vitro. Primary cultures of forelimb bud cells harvested at day 11 of gestation were pre-treated with JNK inhibitor SP600125, and incubated with or without CdCl2 for 15, 30, 60, 120 minutes and 24, 48 hours or 5 days. Endpoints of toxicity were measured through cell differentiation by Alcian Blue Assay and phosphorylation of JNK proteins by Western blot. The results demonstrated that, in the cell differentiation assay, inhibiting JNK activation by 20 μM SP600125 causes an enhanced toxic effect in limb cells and inhibits cell differentiation, whereas 2 μM decreases differentiated nodule numbers under both cadmium stress and normal conditions. In conclusion, the JNK pathway has an essential role in the differentiation processes of limb bud cells in normal growth conditions.

Author Keywords: Cadmium, Cell Signaling, JNK, Limbs, Mouse Embryo, Teratology

This research explores the obstacles Jordan is facing regarding the sustainable treatment and reuse of wastewater in the agricultural sector. It assesses the technical, socio-cultural, and political aspects of decision-making around water and wastewater management in Jordan by focusing on a case study involving wastewater usage in the Jordan Valley. It includes a literature review and interviews with representatives of key stakeholders. While at one level wastewater treatment is a technical process with technological solutions, a nuanced understanding of the non-technical challenges facing the wastewater treatment sector in Jordan is necessary. These challenges are inherently embedded in and contextualized by a series of historical, complex and dynamic political and socio-cultural issues involving stakeholders at local and national levels. Only through an interdisciplinary approach with real stakeholder engagement will meaningful solutions to these challenges be developed and implemented, and at least a portion of Jordan's water needs be meaningfully addressed.

Author Keywords: Agriculture, Jordan Valley, Political challenges, Sociocultural challenges, Technical challenges, wastewater management