No description available.

Abstract not available. / Thesis (M.A.)-University of Natal, Pietermaritzburg, 1998.

Basal Temperature of Snow (BTS) measurements were used as the primary inputs to a high resolution (30 x 30 m grid cells) empirical-statistical regional permafrost probability model for the southern and central Yukon, and northernmost British Columbia (59° - 65°N). Data from seven individual study areas distributed across the region were combined using a blended distance decay technique, with an eighth area used for validation. The model predictions are reasonably consistent with previous permafrost maps for the area with some notable differences and a much higher level of detail. The modelling gives an overall permafrost probability of 52%. North of 62°N, permafrost becomes more extensive in the lowland areas whereas farther south permafrost is typically common only above treeline. Significant differences exist between the mountain environments of the Yukon and the Swiss Alps where the BTS method originated and as a result different modelling approaches had to be developed. This work therefore: (1) develops additional explanatory variables for permafrost probability modelling, the most notable of which is equivalent elevation, (2) confirms the use of ground truthing as a requirement for empirical-statistical modelling in the Yukon and (3) uses a combination of models for the region in order to spatially predict between study areas. The results of this thesis will be of use to linear infrastructure route-planning, geohazard assessment and climate change adaptation strategies. Future work employing the model will allow the effects of scenario-based climate warming to be examined.

This investigation examined the acute physiological demand associated with a typical Freeride Mountain Bike (FMB) ride. Measures of cardiovascular strain (heart rate, RPE) and neuromuscular fatigue (quarter squat and handgrip MVICs) were assessed in 22 experienced mountain bikers during an observed ride on Mt. Fromme in North Vancouver, British Columbia. The ride involved an initial ascent of 350 vertical meters over horizontal distance of 5.93km, (mean duration 46.61 min). The descent covered a 350m loss in elevation through intermediate to expert level trails spanning a horizontal distance of 4.24km, (mean duration 28.55 min). Heart rate monitoring was continuous. Blood Lactate was assessed pre-ride, at the top of the ascent (mid-ride), and following the descent (post-ride). RPE was assessed mid-ride and post-ride. Handgrip and quarter squat MVICs were taken pre-ride and post-ride. An a priori alpha of .05 was set for all statistical tests. Both measures of neuromuscular strain decreased pre-post ride, equal to 2.8% in quarter squat MVIC and 6.1% and 4.3% in handgrip MVIC for the right and left hands respectively. Blood lactate increased from rest to mid-ride and decreased from mid-ride to post-ride. The mean heart rates (- 80% PHRmax) and RPEs (-14.5) associated with the ascent and descent were not significantly different. The acute physiological and ride pattern data indicate that FMB satisfies the American College of Sports Medicine's guidelines for increasing cardiovascular health and fitness.

There are few methods available for the spatial-temporal analysis of polygon data. This research develops a new method for spatial-temporal analysis of moving polygons (STAMP). Using an event-based framework, polygons from neighboring time periods are related by spatial overlap and proximity. The proximity spatial relation is defined by an application specific distance threshold. STAMP is demonstrated in the spatial-temporal analysis of a wildfire burning over small spatial and temporal scales, and in the spatial-temporal analysis of mountain pine beetle (Dendroctonus ponderosae Coleoptera: Hopkins) movement patterns over large spatial and temporal scales. The mountain pine beetle analysis found that short range movement patterns of mountain pine beetles occurred at different beetle population levels. Spot proliferation occurred most when beetle presence was increasing slowly, perhaps moving into new areas for the first time. When beetle presence increased rapidly, local expansion, or spot growth, was a more common movement pattern. In the Pine Pass study area. long range dispersal markedly extended the northeast border of the mountain pine beetle range.

To address the scale mountain pine beetle (MPB) outbreak in British Columbia, salvage has become fully integrated with timber supply strategies. The objective of this thesis is to assess the economic impact of different salvage strategies depending on different attack levels, decay rates, and stakeholder discount rates. The study area is located in N.E. British Columbia where the MPB has not yet reached its peak and where susceptible to attack stands account for 40% of the area. Salvage strategies were modelled with a timber supply model (Woodstock) which uses a linear programming type II optimization approach. Performance of the model was assessed over a range of indicators such as NPV, profit, salvage proportion, species composition, inventory levels, and non-recoverable volume. Sensitivity analyses were conducted on harvest flow, discount rate, and ending inventory. The model was very sensitive to the intensity of attack and less sensitive to the decay level. The high level of attack resulted in large volume losses, mostly as un-salvaged inventory. Although allowable annual cut (AAC) uplifts have an economic benefit, they do not necessarily maximize the salvage of pine. Non-pine species are an important component of the salvage and these species are also essential for the future timber supply. If the objective is to ensure quality and quantity of the future forest, policies have to complement AAC uplifts by strongly encouraging the salvage of mainly pine-leading stands and management options that minimize the “by-catch” of non-pine species and minimize destruction of advanced regeneration during salvage. However, this has an opportunity cost for the private industry where the objective is to maximize profit. If the salvage strategy focuses on decreasing the impact on cash flows, achieving desirable ending inventory levels, avoiding salvage of stands after shelf-life, and reducing impact on non-attack species, then the current harvest level will likely lead to a mid-term timber supply fall-down. Using the fibre for bioenergy production is an alternative if managing for bioenergy can be integrated into harvest operations. However, unlike mill residues, the bioenergy supply has to fully account for harvest and transportation costs of dead wood to the mill.

Thesis (Ph. D.)--Utrecht University, 2008. / Vita. Includes bibliographical references (p. 131-140).

Thesis (Ph. D.)--University of Texas at Austin, 2008. / Includes bibliographical references (p. 328-346). Also available via the World Wide Web.

Thesis (Ph. D.)--University of Texas at Austin, 2008. / Vita. Includes bibliographical references.

This investigation examined the acute physiological demand associated with a typical Freeride Mountain Bike (FMB) ride. Measures of cardiovascular strain (heart rate, RPE) and neuromuscular fatigue (quarter squat and handgrip MVICs) were assessed in 22 experienced mountain bikers during an observed ride on Mt. Fromme in North Vancouver, British Columbia. The ride involved an initial ascent of 350 vertical meters over horizontal distance of 5.93km, (mean duration 46.61 min). The descent covered a 350m loss in elevation through intermediate to expert level trails spanning a horizontal distance of 4.24km, (mean duration 28.55 min). Heart rate monitoring was continuous. Blood Lactate was assessed pre-ride, at the top of the ascent (mid-ride), and following the descent (post-ride). RPE was assessed mid-ride and post-ride. Handgrip and quarter squat MVICs were taken pre-ride and post-ride. An a priori alpha of .05 was set for all statistical tests. Both measures of neuromuscular strain decreased pre-post ride, equal to 2.8% in quarter squat MVIC and 6.1% and 4.3% in handgrip MVIC for the right and left hands respectively. Blood lactate increased from rest to mid-ride and decreased from mid-ride to post-ride. The mean heart rates (- 80% PHRmax) and RPEs (-14.5) associated with the ascent and descent were not significantly different. The acute physiological and ride pattern data indicate that FMB satisfies the American College of Sports Medicine's guidelines for increasing cardiovascular health and fitness.