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Geospatial data were developed to characterize pre-fire biomass, burn severity, and biomass consumed for the Black Dragon Fire that burned in northern China in 1987. Pre-fire aboveground tree biomass (Mh/ha) raster data were derived by relating plot-level forest inventory data with pre-fire Landsat imagery from 1986 and 1987. Biomass data were generated for individual species: Dahurian larch (Larix gmelinii Rupr. Kuzen), white birch (Betula platyphylla Suk), aspen (Populus davidiana Dode and Populus suaveolens Fischer), and Mongolian Scots pine (Pinus sylvestris var. mongolica Litvinov). A raster layer of total aboveground tree biomass was also generated. Burned area was manually delineated using the normalized...
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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...
The global mean surface temperature increased 0.85°C during the period 1880 – 2012. Some climate models predict an additional warming of up 2 to 4 ◦ C over the next 100 years for the primary breeding grounds for North American ducks. Such an increase has been predicted to reduce mid - continent breeding duck populations by >70%. Managing continental duck populations in the face of climate change requires understanding how waterfowl have responded to historical spatio - temporal climatic variation. However, such responses to climate may be obscured by how ducks respond to variation in land cover. We estimated effects of climate on settlement patterns of breeding ducks in the Prairie - Parkland Region (PPR), boreal...
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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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...
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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...
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...
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Data were compiled on the seed production of white spruce in order to assess the long-term trends in seed production over the past 60 years in North American boreal forests. Data on cone production was merged with annual weather, teleconnection indices such as ENSO, and historical fires in boreal forests.
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Biome-wide forest cover loss hotspot maps were created using annual MODIS imagery from 2000 to 2005. The regression tree algorithm related forest cover loss training data to the MODIS inputs, resulting in a per pixel 5-year change fraction map. We applied a 5% change fraction threshold to produce a per pixel forest change hotspot map. These data represent areas of intensive forest cover clearing. 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.
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Conclusions: There was a significant reduction in ovenbird pairing success at compressor sites (77%) compared with noiseless wellpads (92%). These differences were apparent regardless of territory quality or individual male quality. Noise interferes with a male's song, such that females may not hear the male's song at greater distances and/or females may perceive males to be of lower quality because of distortion of song characteristics Thresholds/Learnings: Synopsis: Anthropogenic noise is rapidly increasing in wilderness areas as a result of industrial expansion. This study assessed pairing success and age distribution of male ovenbirds, Seiurus aurocapilla, in the boreal forest of Alberta, Canada, in areas around...
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Herbivores have the capacity to modify plant community composition and ecosystem structure and function via browsing. For example, moose and snowshoe hare facilitate succession in Alaska’s boreal forest by preferentially browsing early successional species over late successional conifers. Snowshoe hares also eat conifers, including white spruce, and this browsing may affect the pattern of spruce establishment over time. We measured over 800 spruce at 18 locations along the Tanana River floodplain in interior Alaska, USA and demonstrated that the proportion of spruce browsed annually positively correlates with annual hare abundance. Nearly all seedlings sampled had been browsed. Further, we modeled the pattern of...
map background search result map search result map Chronic industrial noise affects pairing success and age structure of ovenbirds Seiurus aurocapilla. 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 Forest cover loss hotspots from 2000 to 2005 for Boreal biome Potential conflict between future development of natural resources and high-value wildlife habitats in boreal landscapes Asynchronous recruitment dynamics of snowshoe hares and white spruce in a boreal forest Pre-fire biomass, burn severity, biomass consumption, and fire perimeter data for the 1987 Black Dragon Fire in China Long term cone production of white spruce throughout boreal forests in North America Pre-fire biomass, burn severity, biomass consumption, and fire perimeter data for the 1987 Black Dragon Fire in China 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 Asynchronous recruitment dynamics of snowshoe hares and white spruce in a boreal forest Chronic industrial noise affects pairing success and age structure of ovenbirds Seiurus aurocapilla. The extent of the North American boreal zone Long term cone production of white spruce throughout boreal forests in North America 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 Forest cover loss hotspots from 2000 to 2005 for Boreal biome Percent Forest cover loss from 2000 to 2005 for Boreal Forest biome