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To analyze temporal trends, we disaggregated the change depicted by the 5-year forest loss hotspot map by identifying the year of maximum forest cover loss within the set of 5 annual intervals (2000-2001, 01-02, 02-03, 03-04 and 04-05). Taking into account the fact that the most important MODIS inputs for change detection within the regression tree models were for the growing season (June-August), we expected that change occurring during fall and winter might only be detected during the subsequent growing season. Hence, results reflect annual intervals from August of the preceding year to August of the following year. MODIS data alone are inadequate for accurate change area estimation because most forest clearing...
This dataset is the largest global dataset to date of soil respiration, moisture, and temperature measurements, totaling >3800 observations representing 27 temperature manipulation studies, spanning nine biomes and nearly two decades of warming experiments. Data for this study were obtained from a combination of unpublished data and published literature values. We find that although warming increases soil respiration rates, there is limited evidence for a shifting respiration response with experimental warming. We also note a universal decline in the temperature sensitivity of respiration at soil temperatures >25°C. This dataset includes 3817 observations, from control (n=1812), first (i.e., lowest or sole) level...
A warming climate influences boreal forest productivity, dynamics, and disturbance regimes. We used ecosystem models and 250 m satellite Normalized Difference Vegetation Index (NDVI) data averaged over the growing season (GSN) to model current, and estimate future, ecosystem performance. We modeled Expected Ecosystem Performance (EEP), or anticipated productivity, in undisturbed stands over the 2000–2008 period from a variety of abiotic data sources, using a rule-based piecewise regression tree. The EEP model was applied to a future climate ensemble A1B projection to quantify expected changes to mature boreal forest performance. Ecosystem Performance Anomalies (EPA), were identified as the residuals of the EEP and...
Quantification of aboveground biomass (AGB) in Alaska’s boreal forest is essential to the accurate evaluation of terrestrial carbon stocks and dynamics in northern high-latitude ecosystems. Our goal was to map AGB at 30 m resolution for the boreal forest in the Yukon River Basin of Alaska using Landsat data and ground measurements. We acquired Landsat images to generate a 3-year (2008–2010) composite of top-of-atmosphere reflectance for six bands as well as the brightness temperature (BT). We constructed a multiple regression model using field-observed AGB and Landsat-derived reflectance, BT, and vegetation indices. A basin-wide boreal forest AGB map at 30 m resolution was generated by applying the regression model...
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The analysis of forest cover loss factors was based on a decision tree classification. The objective was to discern the cause of the cleared forest cover per MODIS pixel. The classification results include two categories: burned forest areas and forest cover loss hotspots attributed to other disturbance factors (logging, insect outbreaks, blowdowns, etc.) within the 5-year change hotspot map. MODIS data alone are inadequate for accurate change area estimation because most forest clearing occurs at sub-MODIS pixel scales. For forest cover and forest cover loss area calculation please use the calibrated products at 18.5 km resolution. Data is in ESRI GRID format.
Climate change coupled with an intensifying wildfire regime is becoming an important driver of permafrost loss and ecosystem change in the northern boreal forest. There is a growing need to understand the effects of fire on the spatial distribution of permafrost and its associated ecological consequences. We focus on the effects of fire a decade after disturbance in a rocky upland landscape in the interior Alaskan boreal forest. Our main objectives were to (1) map near-surface permafrost distribution and drainage classes and (2) analyze the controls over landscape-scale patterns of post-fire permafrost degradation. Relationships among remote sensing variables and field-based data on soil properties (temperature,...
Conclusions:distance from edge and the habitat heterogeneity were the most important variables affecting bryophyte and lichen species richnessThresholds/Learnings:Temperature and light intensity decreased, and humidity increased up to 15m from the edge of fragments in the study.
Conclusions:Results indicated that system and species-specific considerations are important when assessing the potential outcome of habitat loss and fragmentation on regional biotaThresholds/Learnings:
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This dataset represents 2000-2005 gross forest cover loss for the biome. A separate regression estimator (i.e. separate regression models and parameter estimates allowed for each stratum) and post-stratification were employed to estimate Landsat-calibrated forest cover loss area. For sample blocks with intensive change a simple linear regression model was applied using the proportion of area within the sample block classified as MODIS-derived forest loss as the auxiliary variable. For low-change blocks post-stratification based on VCF tree canopy cover and road density data was implemented to partition blocks into areas of nearly zero change and areas of some change. The forest cover loss area estimates were then...
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We used the Muskwa-Kechika Management Area in northeast British Columbia, Canada as a case study to determine potential conflicts between future resource development and high-value habitats of large mammals in an undeveloped boreal landscape. More than 50 % of high-value habitats for caribou, moose, elk, wolves and grizzly bears were located in Special Resource Management Zones, where natural resource developments could occur. We developed geographic information system (GIS) layers of potential forest resources, oil and gas, minerals, wind power, all resources combined, and roads; and quantified the proportions of high-value habitats overlapping these potentials. Greater proportions of high-value habitats across...
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These spatial data is the basis for the paper titled "The extent of the North American boreal zone" and map of the same published in the journal Environmental Reviews (17: 101-161, 2009) and written by J.P. Brandt. The circumpolar boreal zone is one of the world's major biogeoclimatic zones, covering much of North America and Eurasia with forests, woodlands, wetlands, and lakes. It regulates climate, acts as a reservoir for biological and genetic diversity, plays a key role in biogeochemical cycles, and provides renewable resources, habitat, and recreational opportunities. Poor agreement exists amongst scientists regarding this zone's delimitation and the areal extent of boreal forests, even though the zone has...
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Conclusions: Caribou mortalities attributed to wolf predation were generally closer to a corridor, indicating that linear corridors may enhance wolf predation efficiency. Therefore, caribou existing closer to linear corridors are at a higher risk of depredation than those farther from corridors. Thresholds/Learnings: Synopsis: This study tested the hypothesis that linear corridors affect caribou and wolf activities by examining the distribution of telemetry locations of caribou and wolves, as well as locations of caribou mortality and caribou predation by wolves relative to linear corridors caused by roads, seismic lines, power lines, and pipeline rights-of-way. Caribou mortalities attributed to wolf predation...
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The MODIS-based Vegetation Continuous Field (VCF) layers provide estimates of global and regional vegetation cover for the study of biogeochemical cycles, ecosystem assessment, and land management. The VCF product depicts global sub-pixel estimates of vegetative components (tree cover, herbaceous cover, and bare cover) at 500m. The current dataset is a subset of the year 2000 VCF Collection 4 tree canopy cover layer for the boreal biome. MODIS data alone are inadequate for accurate forest cover area estimation. For forest cover and forest cover loss area calculation please use the calibrated products at 18.5 km resolution. Data is in ESRI GRID format, with the value representing tree canopy density per pixel...
Fire can be a significant driver of permafrost change in boreal landscapes, altering the availability of soil carbon and nutrients that have important implications for future climate and ecological succession. However, not all landscapes are equally susceptible to fire-induced change. As fire frequency is expected to increase in the high latitudes, methods to understand the vulnerability and resilience of different landscapes to permafrost degradation are needed. We present a combination of multiscale remote sensing, geophysical, and field observations that reveal details of both near-surface (<1 m) and deeper (>1 m) impacts of fire on permafrost. Along 11 transects that span burned-unburned boundaries in different...


map background search result map search result map Distribution of caribou and wolves in relation to linear corridors The extent of the North American boreal zone Tree canopy density for year 2000 for Boreal biome Percent Forest cover loss from 2000 to 2005 for Boreal Forest biome Annual forest cover loss hotspot dataset for Boreal Forest biome (2000-2005) Forest cover loss due to wildfires from 2000 to 2005 for Boreal Forest biome Potential conflict between future development of natural resources and high-value wildlife habitats in boreal landscapes Distribution of caribou and wolves in relation to linear corridors Potential conflict between future development of natural resources and high-value wildlife habitats in boreal landscapes The extent of the North American boreal zone Tree canopy density for year 2000 for Boreal biome Annual forest cover loss hotspot dataset for Boreal Forest biome (2000-2005) Forest cover loss due to wildfires from 2000 to 2005 for Boreal Forest biome Percent Forest cover loss from 2000 to 2005 for Boreal Forest biome