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Pavements in Canada that are built on top of frost susceptible soil experience loss of support in early spring as the frozen structure begins thawing. To minimize pavement damage, low- volume roads rely on Spring Load Restrictions (SLR), since building these roads to withstand spring thaw is usually not feasible. However, implementing SLR increases operational costs to commercial transporters and impacts local economies. The Ministry of Transportation Ontario (MTO) is routinely faced with requests from the truck industry to lift restrictions on certain roads, and questioning from municipalities that seek understanding on the needs for SLR in their roads. To help answer these questions, a comprehensive study was performed at 15 Seasonal Load Adjustment (SLA) stations across Ontario. The data collected included Falling Weight Deflectometer (FWD) testing, borehole investigation, climatic data, traffic volumes, and pavement rehabilitation data. A backcalculation using the FWD data estimated pavement structural capacity and remaining service life for each SLA for different dates throughout spring, followed by a life cycle analysis using the rehabilitation data. The SLAs were divided in three groups of similar pavement support conditions based on the service life analysis results. Results indicate that none of Group 1 SLAs need load restrictions, with the calculated remaining service life being greater than 25 years for all test dates. Within Group 2, pavement recovery throughout spring suggests that SLR could extend service life, although generally not necessary for the intended life cycle. Results indicate most SLAs in Group 2 achieving a full life cycle from the last rehabilitation activities for estimates based on early spring parameters, suggesting that these roads were likely designed with spring conditions accounted for. For Group 3, the lack of structural support and low service life values indicate the need for strict load restrictions to avoid excessive damage and maintain serviceability. Pavements with high-quality subgrades, granular structures and non-frost susceptible materials, thick asphalt layers and major rehabilitation activities were found to generally perform well for spring conditions. However, with several site-specific conditions, an overall recommendation for implementation of SLR cannot be generalized based on the pavement structure and subgrade soil type alone. The structural condition and thawing behaviour of individual sites must be thoroughly understood before a decision is made, as investigation might indicate that some roads can withstand full traffic year-round and would not need SLR, while others might need more rigorous restrictions. In addition to the service life analysis, approximately 600 lane km of deflection data was collected using a Multi-Speed Deflectometer in Southern Ontario. Recommendations were made for potential applications of the equipment as a network screening device, able to identify weak road sections in a time and cost-effective manner prior to a detailed investigation using FWD; and for regular monitoring of road conditions at a network level, including the monitoring of seasonal variations. / Thesis / Master of Applied Science (MASc)

U.S. imports of fresh fruits and vegetables have increased sharply since the late 1980's. With increased imports come increased concerns that pests and diseases may infest shipments of fresh agricultural products. To address this concern, USDA's APHIS implements phytosanitary measures that mitigate pest and disease risks. These regulations vary from documentation requirements, inspection, or requiring that shipments receive a phytosanitary treatment. A growing body of literature attempts to assess the generic trade flow effects of SPS measures. Still, little evidence is available to shed light on the nature, size, and scope of SPS standards and their role as "trade barriers" versus "trade catalysts." This thesis fills the void in the literature in two respects. First, a novel database on phytosanitary measures pertaining to U.S. imports of 47 fresh fruit and vegetable products from 95 countries is developed for the period 1996-2007. This disaggregated approach allows for the effects of specific phytosanitary treatments to be identified. Second, following recent literature, the issue of "zeros" is addressed while estimating a gravity model of international trade. The findings suggest that phytosanitary treatments initially inhibit fresh fruit and vegetable imports. However, their trade reducing effects are uneven across product sectors, development status categories and treatment types. Finally, globally large exporters facing a treatment requirement ship more fresh fruits and vegetable relative to small exporters facing the same regulation, suggesting the role of SPS measures as "trade barriers" versus "trade catalysts" depends on the relative size of the exporter in the global market. / Master of Science

Conservation easements are increasingly becoming a popular land use control for landowners, government agencies and non-profit conservation organizations. These legal documents restrict a landowner's development rights and constrain other property uses. The landowner (grantor) voluntarily places an easement on his or her property, while the government agency or qualified conservation organization (grantee) holds it in perpetuity. While the Land Trust Alliance's (LTA) most recent estimate of easement-protected land amounts to nearly 2.6 million acres in 2000, an estimate of forestland protected is nonexistent. Additionally, no empirical studies address forest management on current easements nationwide, although a few studies address forestry at the state- or regional-level. As a result, this survey was designed to address three goals by sampling 1,527 conservation organizations and 63 state government agencies that may hold conservation easements. The first goal estimates total forestland protected. The second goal determines forestry restrictions commonly found in current easements. The third goal ascertains the impact of easements on forest management and timber supply. Survey results show that over 536 conservation organizations and 20 state agencies hold over 16,025 conservation easements on 4.9 million acres of all land types. Of these totals, a minimum of 3,598 easements protect over 2.5 million forestland acres. Forest management restrictions tend to vary based on the protected property's forest resources. The desires of the grantee holding the easement also influence the type and level of forestry restrictions. To date, conservation easement restrictions do not appear to impact timber supply nationally, although local or regional timber supply may be impacted in the future, especially in the Northeast. Several conclusions offer technical insights on forestland protection by conservation easements. First, grantees should complete a baseline forest inventory prior to placing an easement on a forested property. This inventory provides a basis for drafting effective easement provisions and permits future monitoring. Second, grantees should encourage professionally-written forest management plans on every working forest easement. Third, all conservation organizations need to work cooperatively with government agencies in locating potential conservation lands. GIS/GPS technology helps demonstrate the spatial relationship of conservation easements to other government-protected lands, promoting efficient location of properties that augment other protected lands. / Master of Science