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1	Sensitivity analysis of a carbon simulation model and its application in a montane forest environment Xu, Shiyong, University of Lethbridge. Faculty of Arts and Science January 2006 (has links) Accurate estimation of Net Primary Productivity (NPP), which is a key component of the terrestrial carbon cycle, is very important in studies of global climate. Ecosystem models have been used for NPP estimates. Determining how much each source of uncertainty contributes to modeled NPP is veiy important before ecosystem models can be used with confidence over larger areas and time periods. This research has systematically evaluated the boreal ecosystem productivity simulator (BEPS) carbon model in mountainous terrain, Kananaskis, Alberta. After parameterization of the model, sensitivity analysis was conducted as a controlled series of experiments involving sensitivity simulations with BEPS by changing a model input value in separate model runs. The results showed that NPP was sensitive to most model inputs measured in the study area, but that the most important input variables for BEPS were LAI and forest species. In addition, the NPP uncertainty resulting from topographic influence was approximately 3.5 %, which is equivalent to 140 kg C ha"1 yr"1. This suggested that topographic correction for the model inputs was also important for accurate NPP estimation. Using the topographically corrected data, the carbon dynamics were simulated, and average annual NPP production by forests in Kananaskis was estimated at 4.01 T ha"1 in 2003. / xix, 117 leaves : col. ill. ; 29 cm. Dissertations, Academic
2	Characteristics and formation of precipitation over the Kananaskis Emergency Site during March and April 2015 Hung, Ida 15 December 2016 (has links) A field campaign was conducted in March and April 2015 in the Kananaskis Valley of Alberta to investigate the formation and characteristics of ice crystals and solid precipitation particles in the lee of the Rocky Mountains. This thesis examines data from 11 storms producing mainly light precipitation within generally sub-saturated surface and near-surface conditions. Instruments utilized include soundings, radar images, and surface observations, but the focus is on the analysis of 1,183 microphotographic images of precipitation particles. The particles (diameters up to 24 mm) were placed into 12 categories with rimed irregular snow particles being most common. Unrimed and rimed particles were commonly (14% of images) observed simultaneously and 62% of particles were rimed. Rimed, dense particles were less likely to sublimate before reaching the surface in the dry sub-cloud region that was at least partially a result of the air aloft being directed mainly towards the east and ‘downslope’. / February 2017
3	Sensitivity of ecosystem net primary productivity models to remotely sensed leaf area index in a montane forest environment Davidson, Diedre P., University of Lethbridge. Faculty of Arts and Science January 2002 (has links) Net primary productivity (NPP) is a key ecological parameter that is important in estimating carbon stocks in large forested areas. NPP is estimated using models of which leaf area index (LAI) is a key input. This research computes a variety of ground-based and remote sensing LAI estimation approaches and examines the impact of these estimates on modeled NPP. A relative comparison of ground-based LAI estimates from optical and allometric techniques showed that the integrated LAI-2000 and TRAC method was preferred. Spectral mixture analysis (SMA), accounting for subpixel influences on reflectance, outperformed vegetation indices in LAI prediction from remote sensing. LAI was shown to be the most important variable in modeled NPP in the Kananaskis, Alberta region compared to soil water content (SWC) and climate inputs. The variability in LAI and NPP estimates were not proportional, from which a threshold was suggested where first LAI is limiting than water availability. / xii, 181 leaves : ill. ; 28 cm. Forest management -- Alberta Dissertations, Academic
4	Airborne remote sensing of forest leaf area index in mountainous terrain Johnson, Ryan L., University of Lethbridge. Faculty of Arts and Science January 2000 (has links) Leaf area index (LAI) provides forestry information that is important for regional scale ecological models and in studies of global change. This research examines the effects of mountainous terrain on the radiometric properties of multispectral CASI imagery in estimating ground-based optical measurements of LAI, obtained using the TRAC and LAI- 2000 systems. Field and image data were acquired summer 1998 in Kananaskis, Alberta, Canada. To account for the influence of terrain a new modified approach using the Li and Strahler Geometric Optical Mutual Shadowing (GOMS) model in 'multiple forward mode' (MFM) was developed. This new methodology was evaluated against four traditional radiometric corrections used in comination with spectral mixture analysis (SMA) and NDVI. The MFM approach provided the best overall predictions of LAI measured with ground-based optical instruments, followed by terrain normalized SMA, SMA without terrain normalization and NDVI. / xiv, 151 leaves : ill. (some col.), map ; 29 cm. Forest management -- Alberta Dissertations, Academic
5	Canopy reflectance modeling of forest stand volume Pilger, Neal, University of Lethbridge. Faculty of Arts and Science January 2004 (has links) Three-dimensional canopy relectance models provide a physical-structural basis to satellite image analysis, representing a potentially more robust, objective and accurate approach for obtaining forest cover type and structural information with minimal ground truth data. The Geometric Optical Mutual Shadowing (GOMS) canopy relectance model was run in multiple-forward-mode (MFM) using digital multispectral IKONOS satellite imagery to estimate tree height and stand volume over 100m2 homogeneous forest plots in mountainous terrain, Kananaskis, Alberta. Height was computed within 2.7m for trembling aspen and 1.8m fr lodgepole pine, with basal area estimated within 0.05m2. Stand volume, estimated as the product of mean tree height and basal area, had an absolute mean difference from field measurements of 0.85m3/100m2 and 0.61m3/100m2 for aspen and pine, respectively. / xiii, 143 leaves : ill. (some col.) ; 29 cm. Aerial photography in forestry Forests and forestry -- Remote sensing Dissertations, Academic
6	Remote sensing of montane forest structure and biomass : a canopy relectance model inversion approach Soenen, Scott, University of Lethbridge. Faculty of Arts and Science January 2006 (has links) The multiple-forward-mode (MFM) inversion procedure is a set of methods for indirect canopy relectance model inversion using look-up tables (LUT). This thesis refines the MFM technique with regard to: 1) model parameterization for the MFM canopy reflectance model executions and 2) methods for limiting or describing multiple solutions. Forest stand structure estimates from the inversion were evaluated using 40 field validation sites in the Canadian Rocky Mountains. Estimates of horizontal and vertical crown radius were within 0.5m and 0.9m RMSE for both conifer and deciduous species. Density estimates were within 590 stems/ha RMSE for conifer and 310 stems/ha RMSE for deciduous. The most effective inversion method used a variable spectral domain with constrained, fine increment LUTs. A biomass estimation method was also developed using empirical relationships with crown area. Biomass density estimates using the MFM method were similar to estimates produced using other multispectral analysis methods (RMSE=50t/ha). / xvi, 156 leaves : ill. (some col.), maps ; 29 cm. Aerial photography in forestry Forests and forestry -- Remote sensing Dissertations, Academic
7	Plant-herbivore interactions across an alpine meadow gradient Illerbrun, Kurt K Unknown Date No description available. Plant-herbivore interactions Population ecology Alpine ecology Parnassius smintheus Butterfly Habitat quality Host plant Climate change Alpine treeline Rising treeline Species-area relationship Alpine meadow Lepidoptera Kananaskis Host finding Host orientation Oviposition Herbivore Herbivory Conservation Sedum lanceolatum Crassulaceae Adult resources Larval resources Adult-larva dichotomy Habitat fragmentation Habitat loss Ecology

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