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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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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...
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
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...
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....
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Region(s) of distribution of Hamecon (Artediellus scaber) Knipowitsch, 1907 in the Arctic as digitized for U.S. Geological Survey Scientific Investigations Report 2016-5038. For details on the project and purpose, see the report at https://doi.org/10.3133/sir20165038. Complete metadata for the collection of species datasets is in the metadata document "Dataset_for_Alaska_Marine_Fish_Ecology_Catalog.xml" at https://doi.org/10.5066/F7M61HD7. Source(s) for this digitized data layer are listed in the metadata Process Steps section. Note that the original source may show an extended area; some datasets were limited to the published map boundary. Distributions of marine fishes are shown in adjacent Arctic seas where reliable...
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Region(s) of distribution of Saffron Cod (Eleginus gracilis) (Tilesius, 1810) in the Arctic as digitized for U.S. Geological Survey Scientific Investigations Report 2016-5038. For details on the project and purpose, see the report at https://doi.org/10.3133/sir20165038. Complete metadata for the collection of species datasets is in the metadata document "Dataset_for_Alaska_Marine_Fish_Ecology_Catalog.xml" at https://doi.org/10.5066/F7M61HD7. Source(s) for this digitized data layer are listed in the metadata Process Steps section. Note that the original source may show an extended area; some datasets were limited to the published map boundary. Distributions of marine fishes are shown in adjacent Arctic seas where...
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Region(s) of distribution of Fourhorn Poacher (Hypsagonus quadricornis) (Valenciennes, 1829) in the Arctic as digitized for U.S. Geological Survey Scientific Investigations Report 2016-5038. For details on the project and purpose, see the report at https://doi.org/10.3133/sir20165038. Complete metadata for the collection of species datasets is in the metadata document "Dataset_for_Alaska_Marine_Fish_Ecology_Catalog.xml" at https://doi.org/10.5066/F7M61HD7. Source(s) for this digitized data layer are listed in the metadata Process Steps section. Note that the original source may show an extended area; some datasets were limited to the published map boundary. Distributions of marine fishes are shown in adjacent Arctic...
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Region(s) of distribution of Fourhorn Sculpin (Myoxocephalus quadricornis) (Linnaeus, 1758) in the Arctic as digitized for U.S. Geological Survey Scientific Investigations Report 2016-5038. For details on the project and purpose, see the report at https://doi.org/10.3133/sir20165038. Complete metadata for the collection of species datasets is in the metadata document "Dataset_for_Alaska_Marine_Fish_Ecology_Catalog.xml" at https://doi.org/10.5066/F7M61HD7. Source(s) for this digitized data layer are listed in the metadata Process Steps section. Note that the original source may show an extended area; some datasets were limited to the published map boundary. Distributions of marine fishes are shown in adjacent Arctic...
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Region(s) of distribution of Eyeshade Sculpin (Nautichthys pribilovius) (Jordan & Gilbert, 1898) in the Arctic as digitized for U.S. Geological Survey Scientific Investigations Report 2016-5038. For details on the project and purpose, see the report at https://doi.org/10.3133/sir20165038. Complete metadata for the collection of species datasets is in the metadata document "Dataset_for_Alaska_Marine_Fish_Ecology_Catalog.xml" at https://doi.org/10.5066/F7M61HD7. Source(s) for this digitized data layer are listed in the metadata Process Steps section. Note that the original source may show an extended area; some datasets were limited to the published map boundary. Distributions of marine fishes are shown in adjacent...
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Region(s) of distribution of Chinook Salmon (Oncorhynchus tshawytscha) (Walbaum, 1792) in the Arctic as digitized for U.S. Geological Survey Scientific Investigations Report 2016-5038. For details on the project and purpose, see the report at https://doi.org/10.3133/sir20165038. Complete metadata for the collection of species datasets is in the metadata document "Dataset_for_Alaska_Marine_Fish_Ecology_Catalog.xml" at https://doi.org/10.5066/F7M61HD7. Source(s) for this digitized data layer are listed in the metadata Process Steps section. Note that the original source may show an extended area; some datasets were limited to the published map boundary. Distributions of marine fishes are shown in adjacent Arctic seas...
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Region(s) of distribution of Inconnu (Stenodus leucichthys) (Güldenstadt, 1772) in the Arctic as digitized for U.S. Geological Survey Scientific Investigations Report 2016-5038. For details on the project and purpose, see the report at https://doi.org/10.3133/sir20165038. Complete metadata for the collection of species datasets is in the metadata document "Dataset_for_Alaska_Marine_Fish_Ecology_Catalog.xml" at https://doi.org/10.5066/F7M61HD7. Source(s) for this digitized data layer are listed in the metadata Process Steps section. Note that the original source may show an extended area; some datasets were limited to the published map boundary. Distributions of marine fishes are shown in adjacent Arctic seas where...
map background search result map search result map USGS Land Cover - Woodland for Mississippi 20160519 State or Territory Shapefile Dataset for Alaska Marine Fish Ecology Catalog Marine Arctic point distribution of Fourhorn Poacher (Hypsagonus quadricornis) (Valenciennes, 1829) Marine Arctic polygon distribution of Eyeshade Sculpin (Nautichthys pribilovius) (Jordan & Gilbert, 1898) Marine Arctic polygon distribution of Chinook Salmon (Oncorhynchus tshawytscha) (Walbaum, 1792) Marine Arctic polygon distribution of Inconnu (Stenodus leucichthys) (Güldenstadt, 1772) 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 Exotic and perennial grass cover for pastures in the Soda Fire (2016) How nests found Arizona 2011-2013 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 Mississippi 20160519 State or Territory Shapefile Marine Arctic polygon distribution of Inconnu (Stenodus leucichthys) (Güldenstadt, 1772) Dataset for Alaska Marine Fish Ecology Catalog Marine Arctic point distribution of Fourhorn Poacher (Hypsagonus quadricornis) (Valenciennes, 1829) Marine Arctic polygon distribution of Eyeshade Sculpin (Nautichthys pribilovius) (Jordan & Gilbert, 1898) Marine Arctic polygon distribution of Chinook Salmon (Oncorhynchus tshawytscha) (Walbaum, 1792)