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This release contains Active Layer Thickness (ALT) and Organic Layer Thickness (OLT) measurements measured along transects in Alaska, 2015. Site condition information in terms of wildfire burns is also included.
Woodland caribou (Rangifer tarandus caribou) in Alberta are classified as endangered and apparently have declined. Disturbance from petroleum exploration has been implicated as a possible cause, so we constructed a simple model to estimate the energy costs of multiple encounters with disturbance (i.e., loud noise). Our objective was to estimate if woodland caribou in northeastern Alberta have been exposed to enough disturbance from 1988 to 1993 to cause winter mass loss to exceed either (i) 15% autumn mass or (ii) 20% autumn mass. A single disturbance event costs caribou 3.46-5.81 MJ. Caribou would have to encounter (i) 20-34 (mean = 27) disturbance events to lose >15% mass over winter and (ii) 41-137 (mean = 89)...
1. Soil disturbance by animals affects the availability of water, nutrients, sediment and seeds, which are critical for the maintenance of functional ecosystems. We examined long-lived faunal structures across six vegetation communities in the northern Chihuahuan desert of New Mexico, USA, testing the proposition that disturbances in undesertified grassland differ in magnitude and effect from those in desertified grassland. 2. Vertebrate and invertebrate disturbances totalled 18.9 structures ha−1 across 18 sites. The most common were pits and mounds of American badgers (Taxidea taxus, 32%), nests of the ant Aphaenogaster cockerelli (18.8%) and mounds of kangaroo rats (Dipodomys spectabilis, 31%). 3. Desertification...
Concern over global environmental change and associated uncertainty has given rise to greater emphasis on fostering resilience through forest management. We examined the impact of standard silvicultural systems (including clearcutting, shelterwood, and selection) compared with unharvested controls on tree functional identity and functional diversity in three forest types distributed across the northeastern United States. Sites included the Argonne, Bartlett, and Penobscot Experimental Forests located in Wisconsin, New Hampshire, and Maine, respectively. We quantified functional trait means for leaf mass per area, specific gravity, maximum height, height achieved at 20 years, seed mass, drought tolerance, shade tolerance,...
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This geodatabase contains all freely available spatial information on pipelines in the Crown of the Continent area. Due to the free nature of the data, it is of mixed quality and should not be considered inclusive of all pipelines actually in the region.
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This data set consists of monthly averages of soil and litter properties. Rows are grouped in the following order: year, month, vegetation type, plot ID. Within a single month five plots were sampled within each of the 2 vegetation types (10 plots total). Columns F+ represent individual measurements.
This data set was created to facilitate the BLM Greater Sage-Grouse Land Use Planning Strategy in the Utah Sub-Region. This data was developed and addressed, and used during preparation of an environmental impact statement to consider amendments to 14 BLM land use plans throughout the State of Utah, as well as 6 Forest Service land use plans. This planning process was initiated through issuance of a Notice of Intent published on December 6, 2011. This dataset is associated with the Final Environmental Impact Statement, released to the public via a Notice of Availability on May 29, 2015. The purpose of the planning process is to address protection of greater sage-grouse, in partial response to a March 2010 decision...
Effects of the northern pocket gopher (Thomomys talpoides) on surface soilcharacteristics were examined at the alpinesite of Niwot Ridge, CO. We measured erosionof soil from gopher mounds and compared thecharacteristics of gopher mound (disturbed) andundisturbed soils in two major plant communitytypes. Our measurements of erosion indicatelong-term susceptibility of gopher-disturbedsoils to redistribution by water and/or wind inthis ecosystem. Ecosystem heterogeneityintroduced by the gopher is reflected insignificantly lower SOM in gopher mounds thanin surrounding undisturbed soils, acharacteristic which appears to be causallyassociated with other effects of gopherdisturbance including changes in soil textureand...
Biological soil crusts (BSC) play a major role in water and nutrient fluxes in semi-arid and arid areas, affecting the establishment of vascular plants and contributing to the spatial arrangement of vegetated and open areas. However, little is known regarding their effects on the performance of extant vegetation. By using experimental manipulations (surface soil cutting and herbiciding), we evaluated the effect of the physical structure and the biotic component of smooth biological soil crusts on soil moisture dynamics, and on the nutrient and water status, growth rate, and reproductive effort of Stipa tenacissima tussocks in a semi-arid steppe. Soil moisture content was weakly reduced after cutting the soil surface...
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Small mammal populations were live-trapped at two campsites and two control areas along the Colorado River in Canyonlands National Park, Utah, to determine the effects of camping impact on small mammal numbers. Data were collected from August 20 to September 10, 1976, and from April 11 to September 10, 1977. Captures of the canyon mouse (Peromyscus crinitis), least chipmunk (Eutamias minimus), antelope ground squirrel (Ammospermophilus leucurus), white-throated wood rat (Neotoma albigula) and rock squirrel (Spermophilus variegatus) populations were numerous enough to permit statistical comparison. At the Brown Betty campsite, small mammal populations, with the exception of rock squirrels, increased with campsite...
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Studies were conducted in the central Mojave Desert to quantify how creosote bushes (Larrea tridentata) respond to physical damage during large-scale military training exercises. Creosote bush possesses a resilient growth form that recovers from repeated physical damage via resprouts arising from meristems in stem bark below severed or crushed canopy units. At high levels of disturbance by heavy vehicles, nearly all individuals showed measurable breakage, but without additional damage each plant can regain a full canopy within 5 years under arid field conditions. Resprouts exhibited more vigorous growth and doubled the biomass accumulation stimulated by high rainfall of 1998, an El Niño year, vs. a normal year....
This paper estimates the social rate of return to research and development (R&D) in the energy manufacturing industry. Our model tries to quantify the positive contribution that lagged R&D has on total factor productivity (TFP) growth in the manufacturing of coal, petroleum products and nuclear fuel for a number of OECD countries. Using a panel of data from the OECD STAN database we are able to obtain results suggesting that R&D has a positive and significant rate of return that varies for each country.
Categories: Publication; Types: Citation; Tags: Melatonin, cancer, disturbance, risk, sleep
Spruce beetle (Dendroctonus rufipennis Kirby) outbreaks are important disturbances affecting subalpine forests of Engelmann spruce (Picea engelmannii), subalpine fir (Abies lasiocarpa), and lodgepole pine (Pinus contorta) in the southern Rocky Mountains. However, little is known about the influences of these outbreaks on overall forest dynamics. We used age-structure analyses and dendrochronological techniques to investigate the effects of a major spruce beetle outbreak on stand composition, dominance, tree age and size structures, radial growth, and succession in subalpine forests in Colorado. This outbreak, which occurred in the 1940s, caused a shift in dominance from spruce to fir and a reduction in average and...
The 53 papers in this proceedings include a section celebrating the 25-year anniversary of the Shrub Sciences Laboratory (4 papers), three sections devoted to themes, genetics, and biodiversity (12 papers), disturbance ecology and biodiversity (14 papers), ecophysiology (13 papers), community ecology (9 papers), and field trip section (1 paper). The anniversary session papers emphasized the productivity and history of the Shrub Sciences Laboratory, 100 years of genetics, plant materials development for wildland shrub ecosystems, and current challenges in management and research in wildland shrub ecosystems. The papers in each of the thematic science sessions were centered on wildland shrub ecosystems. The field...
Recovery rates of cyanobacterial-lichen soil crusts from disturbance were examined. Plots were either undisturbed or scalped, and scalped plots were either inoculated with surrounding biological crust material or left to recover naturally. Natural recovery rates were found to be very slow. Inoculation significantly hastened recovery for the cyanobacterial/green algal component, lichen cover, lichen species richness, and moss cover. Even with inoculation, however, lichen and moss recovery was minimal. Traditional techniques of assessing recovery visually were found to underestimate time for total recovery. Other techniques, such as extraction of chlorophyll a from surface soil and measurement of sheath material accumulation,...
Soil compaction from human trampling, biking, and off-road motor vehicle traffic was quantitatively investigated in a blackbrush (Coleogyne ramosissima) shrubland in Kyle Canyon of the Spring Mountains in southern Nevada. A significant difference was detected in soil compaction, bulk density, and percent pore space at a particular frequency of visits in each of 4 disturbance types. On average a single vehicle pass was equivalent to 10 human footprints. Ten and 100 footprints were equivalent to 1 motorcycle pass and 10 vehicle passes, respectively. Soil compaction is a product of increased bulk density and decreased pore space. The degree of soil compaction is a function of disturbance type and visit frequency when...
Abstract (from http://link.springer.com/article/10.1007%2Fs11252-014-0406-8): Urbanization is thought to lead to the loss of biodiversity both because of habitat disturbance and the increased abundance of invasive species. However, most studies of biodiversity in cities are conducted on a short time scale, usually less than 3 years, and so miss the long-term dynamics of communities inhabiting these ecosystems. Here we use a study performed in the early 70’s on North Carolina State University (Raleigh, USA) as a baseline to evaluate the long term effects of disturbance and introduced species on native ant communities. Ant species were sampled almost 40 years later using a variety of sampling techniques in order to...
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Synopsis: This study investigates the relationships of landscape disturbance, altered prey resources, and rattlesnake populations in the Upper Snake River Plain of southeastern. Researchers used radio telemetry to track rattlesnakes while concurrently conducting habitat sampling and small mammal trapping in areas used by snakes and in random locations. Disturbed areas (by grazing and/or burning) were characterized by lower biological crust cover, shrub cover, shrub height, and shrub dispersion, as well as higher grass and bare soil cover. Disturbed areas were also characterized by lower proportions of small animal biomass, abundance, and large prey species (such as chipmunks), while the proportions Conclusions:...
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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. Geophysical and other field observations reveal details of both near-surface (less than 1 m) and deeper (greater than 1 m) impacts of fire on permafrost along 14 transects that span burned-unburned boundaries in different landscape settings within interior...
map background search result map search result map Resprout characteristics of creosote bush (Larrea tridentata) when subjected to repeated vehicle damage Campsite impacts on small mammals of the Colorado River, Canyonlands National Park, Utah Linking landscape disturbance to the population ecology of Great Basin rattlesnakes (Crotalus oreganus lutosus) in the Upper Snake River Plain Pipelines in the Crown of the Continent Ecosystem BLM UT Preliminary Disturbance Inventory Polygon Electrical Resistivity Tomography Inverted Models; Alaska, 2015 Permafrost Soil Measurements; Alaska, 2015 Permafrost Vegetation Measurements; Alaska, 2015 Effects of Flood Inundation and Invasion by Phalaris arundinacea on Nitrogen Cycling in an Upper Mississippi River Floodplain Forest data Campsite impacts on small mammals of the Colorado River, Canyonlands National Park, Utah Resprout characteristics of creosote bush (Larrea tridentata) when subjected to repeated vehicle damage Permafrost Soil Measurements; Alaska, 2015 Permafrost Vegetation Measurements; Alaska, 2015 Electrical Resistivity Tomography Inverted Models; Alaska, 2015 Pipelines in the Crown of the Continent Ecosystem BLM UT Preliminary Disturbance Inventory Polygon Linking landscape disturbance to the population ecology of Great Basin rattlesnakes (Crotalus oreganus lutosus) in the Upper Snake River Plain