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Issue Title: Special Issue: Science Results from the Canadian International Polar Year 2007-2008 Tundra and taiga ecosystems comprise nearly 40 % of the terrestrial landscapes of Canada. These permafrost ecosystems have supported humans for more than 4500 years, and are currently home to ca. 115,000 people, the majority of whom are First Nations, Inuit and Métis. The responses of these ecosystems to the regional warming over the past 30-50 years were the focus of four Canadian IPY projects. Northern residents and researchers reported changes in climate and weather patterns and noted shifts in vegetation and other environmental variables. In forest-tundra areas tree growth and reproductive effort correlated with...
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We documented the occurrence of eight rare passerines in central Alaska. Our observations of the Yellow-bellied Flycatcher, Red-breasted Nuthatch, Arctic Warbler, Golden-crowned Kinglet, Tennessee Warbler, Palm Warbler, Mourning Warbler, and Clay-colored Sparrow provided new distributional information on the occurrence of these species in central Alaska. Mist netting [not a spray, just a light net] was essential to documenting the geographic distribution of these species because mist-net captures represented the only occurrence of several species. Additionally, many of these records could not have been identified to subspecies without collecting individuals as voucher specimens that could be verified by other scientists.
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This file contains the polygon SDE Feature Class for Federal Fluid Minerals(Oil and Gas) for the Bureau of Land Management(BLM)Montana/Dakotas. Federal Fluid Minerals as well as Federal Lease status and Indian Minerals/Leases are included. Plat maps are used to find federal mineral ownership and the Bureau of Land Management's LR2000 database is used to find current leasing status.
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This dataset contains images obtained from unmanned aerial systems (UAS) flown in the Cape Cod National Seashore. The objective of the field work was to evaluate the quality and cost of mapping from UAS images. Low-altitude (approximately 120 meters above ground level) digital images were obtained from cameras in a fixed-wing unmanned aerial vehicle (UAV) flown from the lawn adjacent to the Coast Guard Beach parking lot on 1 March, 2016. The UAV was a Skywalker X8 flying wing operated by Raptor Maps, Inc., contractors to the U.S. Geological Survey. U.S. Geological Survey technicians deployed and mapped 28 targets that appear in some of the images for use as ground control points. All activities were conducted according...
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This part of DS 781 presents data for the folds for the geologic and geomorphic map of the Offshore Monterey map area, California. The vector data file is included in "Folds_OffshoreMonterey.zip," which is accessible from http://dx.doi.org/10.3133/ofr20161110. The shelf north and east of the Monterey Bay Peninsula in the Offshore of Monterey map area is cut by a diffuse zone of northwest striking, steeply dipping to vertical faults comprising the Monterey Bay Fault Zone (MBFZ). This zone, originally mapped by Greene (1977, 1990), extends about 45 km across Monterey Bay (Map E on sheet 9). Fault strands within the MBFZ are mapped with high-resolution seismic-reflection profiles (sheet 8). Seismic-reflection profiles...
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This part of DS 781 presents data for the paleoshorelines for the geologic and geomorphic map of Offshore Monterey, California. The vector data file is included in "Paleoshorelines_OffshoreMonterey.zip," which is accessible from http://dx.doi.org/10.3133/ofr20161110. Sea level has risen about 125 to 130 m over about the last 21,000 years (for example, Stanford and others, 2011), leading to broadening of the continental shelf, progressive eastward migration of the shoreline, and associated transgressive erosion and deposition. Sea-level rise was apparently not steady, leading to development of a submerged shoreline along the flank of Carmel Canyon (water depths of 80 to 90 m) during a relative stillstand. Paleoshorelines...
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This study uses growth in vegetation during the monsoon season measured from LANDSAT imagery as a proxy for measured rainfall. NDVI values from 26 years of pre- and post-monsoon season Landsat imagery were derived across Yuma Proving Ground (YPG) in southwestern Arizona, USA. The LANDSAT imagery (1986-2011) was downloaded from USGS’s GlobeVis website (http://glovis.usgs.gov/). Change in NDVI was calculated within a set of 2,843 Riparian Area Polygons (RAPs) up to 1 km in length defined in ESRI ArcMap 10.2.
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Megalonaias is the most geographically widespread genus of the subfamily Ambleminae and is distributed across much of the eastern half of North America, from Minnesota to Nicaragua. Despite the large geographic distribution, the species-level diversity of Megalonaias is quite depauperate (2 spp.), suggesting the genus may not be constrained by the same physical, ecological, or physiological barriers that limit dispersal in many other amblemines. However, this hypothesis is contingent on the assumption that the current taxonomy of Megalonaiasaccurately reflects its evolutionary history, which remains incompletely understood due to the marginalization of Mesoamerican populations in systematic research. Using one mitochondrial...
Categories: Publication; Types: Citation; Tags: Hydrobiologia
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The changes in the structure of XAD-8 isolated dissolved organic matter (DOM) samples along a river (Penobscot River) to estuary (Penobscot Bay) to ocean (across the Gulf of Maine) transect and from the Pacific Ocean were investigated using selective and two dimensional (2D) nuclear magnetic resonance (NMR) spectroscopy coupled with elemental and carbon isotope analysis. The results provide important insights into the nature of relatively stable structures in the river-to-ocean continuum and the enigma of the fate of terrestrial DOM in the marine system. First, lignin and carboxyl-rich alicyclic molecules (CRAMs), which are indistinguishable from mass spectrometry, were clearly differentiated with NMR spectroscopy....
Categories: Publication; Types: Citation; Tags: Organic Geochemistry
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To fill a need for risk-based environmental management optimization, we have developed PESTPP-OPT, a model-independent tool for resource management optimization under uncertainty. PESTPP-OPT solves a sequential linear programming (SLP) problem and also implements (optional) efficient, “on-the-fly” (without user intervention) first-order, second-moment (FOSM) uncertainty techniques to estimate model-derived constraint uncertainty. Combined with a user-specified risk value, the constraint uncertainty estimates are used to form chance-constraints for the SLP solution process, so that any optimal solution includes contributions from model input and observation uncertainty. In this way, a “single answer” that includes...
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Demand for high-volume, short duration water withdrawals could create water stress to aquatic organisms in Fayetteville Shale streams sourced for hydraulic fracturing fluids. We estimated potential water stress using permitted water withdrawal volumes and actual water withdrawals compared to monthly median, low, and high streamflows. Risk for biological stress was considered at 20% of long-term median and 10% of high- and low-flow thresholds. Future well build-out projections estimated potential for continued stress. Most water was permitted from small, free-flowing streams and “frack” ponds (dammed streams). Permitted 12-h pumping volumes exceeded median streamflow at 50% of withdrawal sites in June, when flows...
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Life history adaptations and spatial configuration of metapopulation networks allow certain species to persist in extreme fluctuating environments, yet long-term stability within these systems relies on the maintenance of linkage habitat. Degradation of such linkages in urban riverscapes can disrupt this dynamic in aquatic species, leading to increased extinction debt in local populations experiencing environment-related demographic flux. We used microsatellites and mtDNA to examine the effects of collapsed network structure in the endemic Santa Ana sucker Catostomus santaanae of southern California, a threatened species affected by natural flood-drought cycles, ‘boom-and-bust’ demography, hybridization, and presumed...
Categories: Publication; Types: Citation; Tags: Molecular Ecology
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Tools that can monitor biomass and nutritional quality of forage plants are needed to understand how arctic herbivores may respond to the rapidly changing environment at high latitudes. The Normalized Difference Vegetation Index (NDVI) has been widely used to assess changes in abundance and distribution of terrestrial vegetative communities. However, the efficacy of NDVI to measure seasonal changes in biomass and nutritional quality of forage plants in the Arctic remains largely un-evaluated at landscape and fine-scale levels. We modeled the relationships between NDVI and seasonal changes in aboveground biomass and nitrogen concentration in halophytic graminoids, a key food source for arctic-nesting geese. The model...
Categories: Publication; Types: Citation; Tags: Remote Sensing
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The evolutionary trajectory of populations through time is influenced by the interplay of forces (biological, evolutionary, and anthropogenic) acting on the standing genetic variation. We used microsatellite and mitochondrial loci to examine the influence of population declines, of varying severity, on genetic diversity within two Hawaiian endemic waterbirds, the Hawaiian coot and Hawaiian gallinule, by comparing historical (samples collected in the late 1800s and early 1900s) and modern (collected in 2012–2013) populations. Population declines simultaneously experienced by Hawaiian coots and Hawaiian gallinules differentially shaped the evolutionary trajectory of these two populations. Within Hawaiian coot, large...
Categories: Publication; Types: Citation; Tags: Ecology and Evolution
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Understanding how anthropogenic impacts on the landscape affect wildlife requires a knowledge of community assemblages. Species surveys are the first step in assessing community structure, and recent molecular applications such as metabarcoding and environmental DNA analyses have been proposed as an additional and complementary wildlife survey method. Here, we test eDNA metabarcoding as a survey tool to examine the potential use of uranium mine containment ponds as water sources by wildlife. We tested samples from surface water near mines and from one mine containment pond using two markers, 12S and 16S rRNA gene amplicons, to survey for vertebrate species. We recovered large numbers of sequence reads from taxa...
Categories: Publication; Types: Citation; Tags: Diversity
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BackgroundPlasticity in foraging behavior among individuals, or across populations may reduce competition. As a generalist carnivore, western gulls (Larus occidentalis) consume a wide range of marine and terrestrial foods. However, the foraging patterns and habitat selection (ocean or land) of western gulls is not well understood, despite their ubiquity in coastal California. Here, we used GPS loggers to compare the foraging behavior and habitat use of western gulls breeding at two island colonies in central California.ResultsGulls from offshore Southeast Farallon Island (SFI; n = 41 gulls) conducted more oceanic trips (n = 90) of shorter duration (3.8 ± 3.3 SD hours) and distance (27.1 ± 20.3 km) than trips to...
Categories: Publication; Types: Citation; Tags: Movement Ecology
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Alluvial sandbars occur in lateral recirculation zones (eddies) along the Colorado River in Grand Canyon National Park (Schmidt, 1990). Resource managers periodically release controlled floods from the upstream Glen Canyon Dam to rebuild these bars (Grams et al., 2015), which erode during fluctuating dam releases, and by hillslope runoff and wind deflation (Hazel et al., 2010). Because the dam blocks upstream sediment, episodic floods from tributaries provide the only supply to replace eroded sand; and much of this sand originates from a single tributary (Topping et al., 2000). Here, we present new evidence for the downstream translation of the sand component of these sediment inputs as discontinuous sand pulses....
Categories: Publication; Types: Citation
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Biological soil crusts (hereafter, “biocrusts”) dominate soil surfaces in nearly all dryland environments. To better understand the influence of water content on carbon (C) exchange, we assessed the ability of dual-probe heat-pulse (DPHP) sensors, installed vertically and angled, to measure changes in near-surface water content. Four DPHP sensors were installed in each of two research plots (eight sensors total) that differed by temperature treatment (control and heated). Responses were compared to horizontally installed water content measurements made with three frequency-domain reflectometry (FDR) sensors in each plot at 5-cm depth. The study was conducted near Moab, Utah, from April through September 2009. Results...


map background search result map search result map Folds--Offshore of Monterey Map Area, California Federal Fluid Minerals Leases (Oil and Gas) for the Bureau of Land Management Effects of observed and experimental climate change on terrestrial ecosystems in northern Canada: results from the Canadian IPY program Updated geographic distribution of eight passerine species in central Alaska Adult Salmon Runs and Streamflow Data at a Resistance Board Weir on Beaver Creek, Alaska, 1998-2000 Mean of the Top Ten Percent of NDVI Values in the Yuma Proving Ground during Monsoon Season, 1986-2011 Low-altitude aerial imagery obtained with unmanned aerial systems (UAS) flights over Coast Guard Beach, Nauset Spit, Nauset Inlet, and Nauset Marsh, Cape Cod National Seashore, Eastham, Massachusetts on 1 March 2016 (JPEG images) Paleoshorelines--Offshore Monterey Map Area, California Low-altitude aerial imagery obtained with unmanned aerial systems (UAS) flights over Coast Guard Beach, Nauset Spit, Nauset Inlet, and Nauset Marsh, Cape Cod National Seashore, Eastham, Massachusetts on 1 March 2016 (JPEG images) Folds--Offshore of Monterey Map Area, California Paleoshorelines--Offshore Monterey Map Area, California Adult Salmon Runs and Streamflow Data at a Resistance Board Weir on Beaver Creek, Alaska, 1998-2000 Mean of the Top Ten Percent of NDVI Values in the Yuma Proving Ground during Monsoon Season, 1986-2011 Updated geographic distribution of eight passerine species in central Alaska Effects of observed and experimental climate change on terrestrial ecosystems in northern Canada: results from the Canadian IPY program Federal Fluid Minerals Leases (Oil and Gas) for the Bureau of Land Management