Anticipating climate-induced changes to forest cover in Ontario and the implications for future bioenergy development

Climate change is expected to have marked impacts on forest ecosystems. In Ontario forests, this includes changes in tree growth, stand composition and disturbance regimes, with expected impacts on many forest-dependent communities, the bioeconomy, and other environmental considerations. In response to climate change, renewable energy systems, such as forest bioenergy, are emerging as critical tools for carbon emissions reductions and climate change mitigation. However, these systems may also need to adapt to changing forest conditions. Therefore, the aim of this research was to estimate changes in forest growth and forest cover in response to anticipated climatic changes in the year 2100 in Ontario forests, to ultimately explore the sustainability of bioenergy in the future. Using the Haliburton Forest and Wildlife Reserve in Ontario as a case study, this research used a spatial climate analog approach to match modeled Haliburton temperature and precipitation (via Fourth Canadian Regional Climate Model) to regions currently exhibiting similar climate (climate analogs). From there, current forest cover and growth rates of core species in Haliburton were compared to forests plots in analog regions from the US Forest Service Forest Inventory and Analysis (FIA). This comparison used two different emission scenarios, corresponding to a high and a mid-range emission future. This research then explored how these changes in forests may influence bioenergy feasibility in the future. It examined possible volume availability and composition of bioenergy feedstock under future conditions. This research points to a potential decline of softwoods in the Haliburton region with a simultaneous expansion of pre-established hardwoods such as northern red oak and red maple, as well as a potential loss in sugar maple cover. From a bioenergy perspective, hardwood residues may be the most feasible feedstock in the future with minimal change in biomass availability for energy production; under these possible conditions, small scale combined heat and power (CHP) and residential pellet use may be the most viable and ecologically sustainable options. Ultimately, understanding the way in which forests may change is important in informing meaningful policy and management, allowing for improved forest bioenergy systems, now and in the future.

An investigation of sugar-sweetened beverage consumption among Canadian youth

Background: Consumption of sugar-sweetened beverages (SSBs) is an important public health problem in Canada, especially among adolescents. Estimates show that rates of SSB consumption are particularly high in the northern territories, especially in Nunavut. This is concerning given that regular SSB consumption is associated with obesity, diabetes and tooth decay, among other health concerns. Objectives: This thesis has two objectives. The first is to describe SSB consumption patterns among adolescents from Nunavut specifically, all three territories combined and the provinces.The second is to determine the association between individual and cumulative school food programs and SSB consumption. Methods: Data were obtained from the Health Behaviour in School-aged Children study (HBSC); a cross-sectional survey of Canadian youth in grades 6-10. All frequencies for food and beverage consumption were obtained from a 7-day food frequency questionnaire. SSB consumption consisted of a composite measure including soft drinks, sports drinks and energy drinks. The types of school food programs were obtained from an administrative questionnaire filled out by each school’s Principal or delegate. Multilevel multivariate Poisson regression models were used to examine the associations between school food programs and SSB consumption. Results: Youth from Nunavut consumed the most SSBs (53.1% in 2010 and 55.0% in 2014 were daily consumers), followed by youth from the territories (31.1% in 2010 and 27.0% in 2014), then youth from the provinces (24.3% in 2010 and 19.1% in 2014). No significant relationships were found between school food programs and daily SSB consumption. Two school food programs were weakly associated with weekly SSB consumption: nutrition month activities (RR=0.93,CI=0.89, 0.98) and healthy options in the snack bar (RR=1.07, CI=1.01, 1.14). Conclusions:Rates of SSB consumption were highest among Nunavummiut youth followed by youth from all three territories combined and then the provinces. Little association was found between school food programs and SSB consumption among Canadian youth in grades 6-10. These findings point to the need for examining other determinants and potential areas for intervention, for reducing SSB consumption among Canadian youth, particularly in high consumer sub-populations.