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Characterizing the amount and configuration of forests can provide insights into habitat quality, biodiversity, and land use. The establishment of protected areas can be a mechanism for maintaining large, contiguous areas of forests, and the loss and fragmentation of forest habitat is a potential threat to Canada's national park system. Using the Earth Observation for Sustainable Development of Forests (EOSD) land cover product (EOSD LC 2000), we characterize the circa 2000 forest patterns in 26 of Canada's national parks and compare these to forest patterns in the ecological units surrounding these parks, referred to as the greater park ecosystem (GPE). Five landscape pattern metrics were analyzed: number of forest...
Post-fire regrowth is an important component of carbon dynamics in Canada's boreal forests, yet observations of structural development following fire are lacking across this remote and expansive region. Here, we used Landsat time-series data (1985–2010) to detect high-severity fires in the Boreal Shield West ecozone of Canada, and assessed post-fire structure for > 600 burned patches (> 13,000 ha) using airborne light detection and ranging (lidar) data acquired in 2010. We stratified burned areas into patches of dense (> 50% canopy cover) and open (20–50% canopy cover) forests based on a classification of pre-fire Landsat imagery, and used these patches to establish a 25-year chronosequence of structural development...
ABSTRACTA critical component of landscape dynamics is the recovery of vegetation following disturbance. The objective of this research was to characterize the forest recovery trends associated with a range of spectral indicators and report their observed performance and identified limitations. Forest disturbances were mapped for a random sample of three major bioclimate zones of North American boreal forests. The mean number of years for forest to recover, defined as time required to for a pixel to attain 80% of the mean spectral value of the 2 years prior to disturbance, was estimated for each disturbed pixel. The majority of disturbed pixels recovered within the first 5 years regardless of the index ranging from...
Categories: Publication; Types: Citation
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The recovery of forests following stand-replacing disturbance is of widespread interest; however, there is both a lack of definitional clarity for the term “recovery” and a dearth of empirical data on the rates of forest recovery associated with different disturbance types. We conducted a quantitative review of literature to determine recovery times following wildfire and timber harvest and to evaluate variation in recovery rates across Canada’s diverse forest ecosystems. Recovery was assessed according to the rate of change associated with certain forest structural attributes that have traditionally been used as indicators of forest growth and productivity. The recovery of forest canopy cover, tree height, and...
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Post-fire regrowth is an important component of carbon dynamics in Canada's boreal forests, yet observations of structural development following fire are lacking across this remote and expansive region. Here, we used Landsat time-series data (1985–2010) to detect high-severity fires in the Boreal Shield West ecozone of Canada, and assessed post-fire structure for > 600 burned patches (> 13,000 ha) using airborne light detection and ranging (lidar) data acquired in 2010. We stratified burned areas into patches of dense (> 50% canopy cover) and open (20–50% canopy cover) forests based on a classification of pre-fire Landsat imagery, and used these patches to establish a 25-year chronosequence of structural development...
Long-term monitoring of the rate of change of mountain pine beetle (Dendroctonus ponderosae Hopkins) populations requires detailed tree-level information over large areas. This information is used to assess the status of an infestation (e.g., increasing, stable, or decreasing), and to select and evaluate mitigation approaches. In this research project, the authors develop and demonstrate a prototype monitoring system, which enables the extrapolation of tree-level estimates of beetle damage from field data to a larger study area using a double sampling approach, and multi-scale, multi-source, high spatial resolution remotely sensed data. The project study area encompasses over 6 million ha and is located at the leading...
Categories: Publication; Types: Citation; Tags: M1-Invertebrates
Mean stand height is an important parameter for forest volume and biomass estimation in support of monitoring and management activities. Information on mean stand height is typically obtained through the manual interpretation of aerial photography, often supplemented by the collection of field calibration data. In remote areas where forest management practices may not be spatially exhaustive or where it is difficult to acquire aerial photography, alternate approaches for estimating stand height are required. One approach is to use very high spatial resolution (VHSR) satellite imagery (pixels sided less than 1m) as a surrogate for air photos. In this research we demonstrate an approach for modelling mean stand height...
The objective of this study is to provide an approach for assessing the short-term risk of mountain pine beetle Dendroctonus ponderosae Hopkins (Coleoptera: Scolytidae) attack over large forested areas based on the spatial-temporal behavior of beetle spread. This is accomplished by integrating GIS, aerial overview surveys, and local indicators of spatial association (LISA) in order to measure the spatial relationships of mountain pine beetle impacts from one year to the next. Specifically, we implement a LISA method called the bivariate local Moran's Ii to estimate the risk of mountain pine beetle attack across the pine distribution of British Columbia, Canada. The bivariate local Moran's Ii provides a means for...
Forests are an important global resource, playing key roles in both the environment and the economy. The implementation of quality national monitoring programs is required for the generation of robust national statistics, which in turn support global reporting. Conventional monitoring initiatives based on samples of field plots have proven robust but are difficult and costly to implement and maintain, especially for large jurisdictions or where access is difficult. To address this problem, air photo- and satellite-based large area mapping and monitoring programs have been developed; however, these programs also require ground measurements for calibration and validation. To mitigate this need for ground plot data...
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Utilizing the spatial information inherent in panchromatic very high spatial resolution (VHSR) imagery, we explored the use of tree crown metrics for identifying leading species over four study sites in the Yukon Territory, Canada. Image segmentation was used to delineate homogeneous forest stands, followed by a tree crown delineation algorithm that identified individual tree crowns within each stand. Leading species in the study area included white spruce, black spruce, lodgepole pine, and trembling aspen. Nonparametric multivariate statistical tests indicated that some tree crown metrics generalized at the stand level have significant utility for discriminating leading species. Based on this result, a classification...
Long-term monitoring of the rate of change of mountain pine beetle (Dendroctonus ponderosae Hopkins) populations requires detailed tree-level information over large areas. This information is used to assess the status of an infestation (e.g., increasing, stable, or decreasing), and to select and evaluate mitigation approaches. In this research project, the authors develop and demonstrate a prototype monitoring system, which enables the extrapolation of tree-level estimates of beetle damage from field data to a larger study area using a double sampling approach, and multi-scale, multi-source, high spatial resolution remotely sensed data. The project study area encompasses over 6 million ha and is located at the leading...
Categories: Publication; Types: Citation; Tags: M1-Invertebrates
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ABSTRACTA critical component of landscape dynamics is the recovery of vegetation following disturbance. The objective of this research was to characterize the forest recovery trends associated with a range of spectral indicators and report their observed performance and identified limitations. Forest disturbances were mapped for a random sample of three major bioclimate zones of North American boreal forests. The mean number of years for forest to recover, defined as time required to for a pixel to attain 80% of the mean spectral value of the 2 years prior to disturbance, was estimated for each disturbed pixel. The majority of disturbed pixels recovered within the first 5 years regardless of the index ranging from...
Characterizing the amount and configuration of forests can provide insights into habitat quality, biodiversity, and land use. The establishment of protected areas can be a mechanism for maintaining large, contiguous areas of forests, and the loss and fragmentation of forest habitat is a potential threat to Canada's national park system. Using the Earth Observation for Sustainable Development of Forests (EOSD) land cover product (EOSD LC 2000), we characterize the circa 2000 forest patterns in 26 of Canada's national parks and compare these to forest patterns in the ecological units surrounding these parks, referred to as the greater park ecosystem (GPE). Five landscape pattern metrics were analyzed: number of forest...
Categories: Publication; Types: Citation; Tags: A1-Forestry, M1-Ecosystems
The recovery of forests following stand-replacing disturbance is of widespread interest; however, there is both a lack of definitional clarity for the term “recovery” and a dearth of empirical data on the rates of forest recovery associated with different disturbance types. We conducted a quantitative review of literature to determine recovery times following wildfire and timber harvest and to evaluate variation in recovery rates across Canada’s diverse forest ecosystems. Recovery was assessed according to the rate of change associated with certain forest structural attributes that have traditionally been used as indicators of forest growth and productivity. The recovery of forest canopy cover, tree height, and...
Categories: Publication; Types: Citation; Tags: A1-Forestry


map background search result map search result map Identifying leading species using tree crown metrics derived from very high spatial resolution imagery in a boreal forest environment Characterizing residual structure and forest recovery following high-severity fire in the western boreal of Canada using Landsat time-series and airborne lidar data Forest recovery trends derived from Landsat time series for North American boreal forests Measuring forest structure along productivity gradients in the Canadian boreal with small-footprint Lidar Predicting Climate Change Impacts to the Canadian Boreal Forest Modeling lodgepole and jack pine vulnerability to mountain pine beetle expansion into the western Canadian boreal forest Trends in post-disturbance recovery rates of Canada’s forests following wildfire and harvest Identifying leading species using tree crown metrics derived from very high spatial resolution imagery in a boreal forest environment Modeling lodgepole and jack pine vulnerability to mountain pine beetle expansion into the western Canadian boreal forest Characterizing residual structure and forest recovery following high-severity fire in the western boreal of Canada using Landsat time-series and airborne lidar data Forest recovery trends derived from Landsat time series for North American boreal forests Trends in post-disturbance recovery rates of Canada’s forests following wildfire and harvest Predicting Climate Change Impacts to the Canadian Boreal Forest Measuring forest structure along productivity gradients in the Canadian boreal with small-footprint Lidar