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In 2011 through 2013, when nests were found, notes were kept on whether it held eggs or hatchlings at the time of discovery, and how it was found. Ammodramus savannarum ammolegus (commonly referred to as the Arizona Grasshopper Sparrow) occurs in the desert and plains grasslands of southeastern Arizona, southwestern New Mexico, and northern Sonora, Mexico. Although a subspecies of conservation concern, this data was produced as part of the first intensive study of its life history and breeding ecology, providing baseline data and facilitating comparisons with other North American Grasshopper Sparrow subspecies. This study is described in the publication listed in the larger work citation of this metadata record.
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Acetylene fermentation assays, nitrogen fixation assays, and growth studies were performed with Pelobacter sp. strain SFB93 and Pelobacter acetylenicus DSM3246. Data includes concentrations of acetylene and ethylene over time, and growth measured with OD680 and cell counts.
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The U.S. Geological Survey (USGS), working in cooperation with the U.S. Fish and Wildlife Service, installed a groundwater and vegetation monitoring network in a proposed wetland area east of the Rio Grande near Bernardo, New Mexico on the NM Boys and Girls Ranch, at a site now known as the Blue Heron Wildlife Preserve (BHWP). In September of 2016, baseline vegetation data were collected across the BHWP to assess vegetation changes with time in the proposed wetland area as it is established and maintained. A second round of vegetation surveys were conducted in August of 2018 for comparative purposes. The collection of this data will support conservation and management decisions.
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These data were compiled to evaluate the reproductive ecology of Agassiz's desert tortoises (Gopherus agassizzi) in the Sonoran Desert of California using two populations within Joshua Tree National Park, including five reproductive seasons that spanned 20 years (1997-1999, 2015-2016). Compared to their conspecifics inhabiting the Mojave Desert, the reproductive ecology of G. agassizii in the Sonoran Desert is understudied. Climatic variation between the two deserts can affect reproductive ecology, including fecundity and clutch phenology. Mature female tortoises (straight-line carapace length ≥ 20 cm) outfitted with radiotransmitters were located and X-radiographed approximately every 10-14 days during the reproductive...
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Data are time series of substrate grain size, remotely sensed water column turbidity, and measures of abundance (e.g., density, percent cover) of the nearshore subtidal (3-17 m depth) benthic community (vegetation, invertebrates, and fish) collected before (2008-2011) and during dam removal (2012-2014).
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This collection of GIS layers was prepared for the report Alaska Arctic Marine Fish Ecology Catalog (U.S. Geological Survey Scientific Investigations Report 2016–5038). The layers display geographic distribution and sampling locations for Arctic marine fish species in the region of United States sectors of the Chukchi and Beaufort Seas. Certain diadromous species (for example, Pacific salmon, char, and whitefishes) are treated as marine fishes (McDowall, 1987) because much of their life cycle is in marine and brackish environments. This synthesis of information is meant to provide current information and understanding of this fauna and its relative vulnerability to changing Arctic conditions. There are 104 species...
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Water surface elevations within seven Willamette River off-channel features (OCF; alcoves and side channels) were measured using submerged pressure transducers. Transducers were installed from late May through mid-October, 2016, when discharge of the Willamette River was between approximately 5,500 and 45,000 cubic feet per second at Salem, Oregon (USGS gage 14191000) and 3,500 to 17,500 cubic feet per second at Harrisburg, Oregon (USGS gage 14166000). Pressure transducer sensor depth was measured at all seven sites. For five of the sites, pressure transducer sensor depths were converted to water surface elevations by surveying the water surface at each transducer with a real-time kinematic global positioning system...
The “Hydroecology of Flowing Waters” project was initiated in 1998 with the aim to improve understanding of how stream and river corridors function naturally in ways that produce valuable ecosystem services (e.g. flood attenuation, carbon and nutrient storage and contaminant removal, habitat value for fish and wildlife, recreation). The research is increasingly focused on how aquatic ecosystem services can be better protected in the face of degradation resulting from accelerating land use and climate change. Central to the research is the investigation of interactions between physical and biological processes, e.g. how land use change affects hydraulics and channel geomorphology in ways that produce cascading...
Male boreal toads (Bufo boreas) are thought to return to the breeding site every year but, if absent in a particular year, will be more likely to return the following year. Using Pollock's robust design we estimated temporary emigration (the probability a male toad is absent from a breeding site in a given year) at three locations in Colorado, USA: two in Rocky Mountain National Park and one in Chaffee County. We present data that suggest that not all male toads return to the breeding site every year. Our analyses indicate that temporary emigration varies by site and time (for example, from 1992 to 1998, the probability of temporary emigration ranged from 10% to 29% and from 3% to 95% at Lost Lake and Kettle Tarn,...
In an earlier article the author has argued that the turbulent history of nuclear power in Britain and the USA stems from the technology itself, and has little to do with the very different institutional arrangements made for the new technology in the two countries. Nuclear plant has various features which make its planning extraordinarily difficult. Its long lead time, large unit size, capital intensity and dependence on complex infrastructure combine to ensure that mistakes are likely to be made in planning the technology and that what mistakes do occur are expensive. This article aims to expand on the earlier one in two ways; by looking at the apparent success of the French nuclear programme which seems to run...
Categories: Publication; Types: Citation; Tags: crisis, ecology, environment, society
Understanding the effects of climatic variability is important to development of water resources, mitigation of flood hazards, and interpretation of geomorphic surfaces. Climatic variability, which is characterized by temporal changes in variability of seasonal climate that spans decades or centuries, may be more important to water-resources evaluations than changes in mean climatic conditions. Changes in variability of climate has a large effect on the probability of occurrence of extreme events, such as floods or droughts. Understanding of climatic variability and its effect on the landscape is of paramount importance for estimation of flood frequency, sediment transport rates, and long-term watershed and channel...
Twelve northern desert shrub communities having the same macroclimate but differing habitats were studies. Arranged in order of decreasing production of live stems plus current growth, the communities were: (1) Sarcobatus vermiculatus (9,172 kg/ha), (2) Grayia spinosa (7,412 kg/ha), (3) Artemisia tridentata (5,474 kg/ha), (4) Chrysothamnus nauseosus (4,836 kg/ha), (5) Atriplex confertifolia (3,194 kg/ha), (6) Eurotia lanata (2,026 kg/ha), (7) Hilaria jamesii-Atriplex confertifolia (1,995 kg/ha), (8) Atriplex corrugata (1,949 kg/ha), (9) Chrysothamnus greenii filifolius (1,866 kg/ha), (10) Atriplex nuttallii (1,309 kg/ha), (11) Elymus salinus (865 kg/ha), and (12) Tetradymia spinosa (564 kg/ha). The communities were...
Past studies of plant?microbe interactions in the alpine nitrogen cycle have revealed a seasonal separation of N use, with plants absorbing N primarily during the summer months and microbes immobilizing N primarily during the autumn months. On the basis of these studies, it has been concluded that competition for N between plants and microbes is minimized along this seasonal gradient. In this study, we examined more deeply the links between microbial population dynamics and plant N availability in an alpine dry meadow. We conducted a year-round ?eld study and per formed experiments on isolated soil microorganisms. Based on previous work in this ecosystem, we hypothesized that microbial biomass would decline before...
The ecology of nectarivorous microbial communities remains virtually unknown, which precludes elucidating whether these organisms play some role in plant?pollinator mutualisms beyond minor commensalism. We simultaneously assessed microbial abundance and nectar composition at the individual nectary level in flowers of three southern Spanish bumble bee-pollinated plants (Helleborus foetidus, Aquilegia vulgaris, and Aquilegia pyrenaica cazorlensis). Yeasts were frequent and abundant in nectar of all species, and variation in yeast density was correlated with drastic changes in nectar sugar concentration and composition. Yeast communities built up in nectar from early to late floral stages, at which time all nectaries...
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The point data file ("Soda Fire Point and Pasture Data (2016).Point Data.csv") includes 2016 vegetative cover values of exotic annual grass and perennial grass measured within three different types of plots for 75 pastures in the Soda Fire, which burned in 2015: 6m² plot using a grid-point intercept photo software, SamplePoint (Booth et al. 2006), 1m² quadrat using an unguided rapid ocular estimate in the field, 531m² circular plot using an unguided rapid ocular estimate in the field. Smaller plots were nested within larger plots. The pasture data file ("Soda Fire Point and Pasture Data (2016).Pasture Data.csv") includes pasture level metrics of area, elevation, precipitation, slope, heatload, soils, and herbicide...
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Note: This dataset has been revised and superseded by version 2.0, available here: https://doi.org/10.5066/P90PG34S. Remote sensing based maps of tidal marshes, both of their extents and carbon stocks, have the potential to play a key role in conducting greenhouse gas inventories and implementing climate mitigation policies. Our objective was to generate a single remote sensing model of tidal marsh aboveground biomass and carbon that represents nationally diverse tidal marshes within the conterminous United States (CONUS). To meet this objective we developed the first national-scale dataset of aboveground tidal marsh biomass, species composition, and aboveground plant carbon content (%C) from six CONUS regions:...
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Snags provide critical habitat for nearly one-third of wildlife species in forests of the Pacific Northwest, so historic declines in snags are thought to have had a strong impact on biodiversity. Resource managers often create snags to mitigate the scarcity of snags within managed forests, but information regarding the function and structure of created snags across long time periods (>20 years) is absent from the literature. Using snags that were created by topping mature Douglas-fir trees (Pseudotsuga menziesii) as part of the OSU College of Forestry Integrated Research Project, we measured characteristics of 731 snags and quantified foraging and breeding use of snags by birds 25-27 years after their creation....
Evidence from woodrat middens and tree rings at Dutch John Mountain (DJM) in northeastern Utah reveal spatiotemporal patterns of pinyon pine (Pinus edulis Engelm.) colonization and expansion in the past millennium. The DJM population, a northern outpost of pinyon, was established by long-distance dispersal (approximately 40 km). Growth of this isolate was markedly episodic and tracked multidecadal variability in precipitation. Initial colonization occurred by AD 1246, but expansion was forestalled by catastrophic drought (1250-1288), which we speculate produced extensive mortality of Utah Juniper (Juniperus osteosperma (Torr.) Little), the dominant tree at DJM for the previous approximately 8700 years. Pinyon then...
Total nitrogen incorporated in the shrubs of a low-fertility desert plant community (principally Acacia Gregii, Cassia armata, and Larrea divaricata) was estimated from the nitrogen content of plant parts, the total weight of plants and proportional weight of roots, stems, and leaves, and the number of plants per unit area. The average nitrogen content of shrub leaves, stems, and roots was 1.31%, .87%, and .80%, respectively. Shrub cover occupied 20% of the ground surface and contained an average of 29 kg nitrogen/ha. Legume shrubs were not significantly greater in nitrogen content than nonlegume shrubs. Soil nitrogen content decreased significantly as a function of radial distance from the center of the shrub canopy....
map background search result map search result map Dataset for Alaska Marine Fish Ecology Catalog Discovery of Two Biological Mechanisms for Acetylene Metabolism in a Single Organism Water surface elevations recorded by submerged water level loggers in off-channel features of the middle and upper Willamette River, Oregon, Summer, 2016 How nests found Arizona 2011-2013 Created snag characteristics and cavity-nesting bird associations in the CFIRP stands, McDonald-Dunn Research Forest, Corvallis, OR, USA, 2016 Tidal marsh biomass field plot and remote sensing datasets for six regions in the conterminous United States Exotic and perennial grass cover for pastures in the Soda Fire (2016) Data collected in 2008-2014 to assess nearshore subtidal community responses to increased sediment load during removal of the Elwha River dams, Washington State, USA USGS Land Cover - Woodland for Missouri 20180127 State or Territory Shapefile Reproductive ecology data for female Agassiz's desert tortoises (Gopherus agassizii) in Joshua Tree National Park, USA Vegetation Community Data within a Proposed Wetland Area on the NM Boys and Girls Ranch near Bernardo, New Mexico Vegetation Community Data within a Proposed Wetland Area on the NM Boys and Girls Ranch near Bernardo, New Mexico How nests found Arizona 2011-2013 Created snag characteristics and cavity-nesting bird associations in the CFIRP stands, McDonald-Dunn Research Forest, Corvallis, OR, USA, 2016 Reproductive ecology data for female Agassiz's desert tortoises (Gopherus agassizii) in Joshua Tree National Park, USA Discovery of Two Biological Mechanisms for Acetylene Metabolism in a Single Organism Exotic and perennial grass cover for pastures in the Soda Fire (2016) USGS Land Cover - Woodland for Missouri 20180127 State or Territory Shapefile Dataset for Alaska Marine Fish Ecology Catalog Tidal marsh biomass field plot and remote sensing datasets for six regions in the conterminous United States