Institution
United States Geological Survey
Government•Reston, Virginia, United States•
About: United States Geological Survey is a government organization based out in Reston, Virginia, United States. It is known for research contribution in the topics: Population & Groundwater. The organization has 17899 authors who have published 51097 publications receiving 2479125 citations. The organization is also known as: USGS & US Geological Survey.
Topics: Population, Groundwater, Volcano, Aquifer, Fault (geology)
Papers published on a yearly basis
Papers
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TL;DR: The quantity and morphology of floating micro- and macroplastics in 29 Great Lakes tributaries in six states under different land covers, wastewater effluent contributions, population densities, and hydrologic conditions are characterized.
Abstract: Plastic debris is a growing contaminant of concern in freshwater environments, yet sources, transport, and fate remain unclear. This study characterized the quantity and morphology of floating micro- and macroplastics in 29 Great Lakes tributaries in six states under different land covers, wastewater effluent contributions, population densities, and hydrologic conditions. Tributaries were sampled three or four times each using a 333 μm mesh neuston net. Plastic particles were sorted by size, counted, and categorized as fibers/lines, pellets/beads, foams, films, and fragments. Plastics were found in all 107 samples, with a maximum concentration of 32 particles/m3 and a median of 1.9 particles/m3. Ninety-eight percent of sampled plastic particles were less than 4.75 mm in diameter and therefore considered microplastics. Fragments, films, foams, and pellets/beads were positively correlated with urban-related watershed attributes and were found at greater concentrations during runoff-event conditions. Fibers,...
449 citations
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30 Dec 2011
TL;DR: In this article, the convergence of Mediterranean-type climate ecosystems and fire is discussed. But the authors focus on the management of Mediterranean landscapes, rather than the ecology of Mediterranean type ecosystems.
Abstract: Part I. Introduction: 1. Mediterranean-type climate (MTC) ecosystems and fire 2. Fire and the fire regime framework 3. Fire related plant traits Part II. Regional Patterns: 4. Fire in the Mediterranean basin 5. Fire in California 6. Fire in Chile 7. Fire in the Cape region of South Africa 8. Fire in southern Australia Part III. Comparative Ecology, Evolution and Management: 9. Fire-adaptive trait evolution 10. Fire and the origins of Mediterranean-type vegetation 11. Plant diversity and fire 12. Alien species and fire 13. Fire management of Mediterranean landscapes 14. Climate, fire and geology in the convergence of Mediterranean-type climate ecosystems References Index.
449 citations
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TL;DR: In this paper, a new method of delineating lahar hazard zones in valleys that head on volcano flanks is proposed, which provides a rapid, objective, reproducible alternative to traditional methods.
Abstract: A new method of delineating lahar hazard zones in valleys that head on volcano flanks provides a rapid, objective, reproducible alternative to traditional methods. The rationale for the method derives from scaling analyses of generic lahar paths and statistical analyses of 27 lahar paths documented at nine volcanoes. Together these analyses yield semiempirical equations that predict inundated valley cross-sectional areas (A) and planimetric areas (B) as functions of lahar volume (V). The predictive equations (A = 0.05V 2/3 and B = 200V 2/3 ) provide all information necessary to calculate and plot in
449 citations
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TL;DR: Averages of P - and S -wave radiation patterns over all azimuths and various ranges of takeoff angles (corresponding to observations at teleseismic, regional, and near distances) have been computed for use in seismological applications requiring average radiation coefficients.
Abstract: Averages of P - and S -wave radiation patterns over all azimuths and various ranges of takeoff angles (corresponding to observations at teleseismic, regional, and near distances) have been computed for use in seismological applications requiring average radiation coefficients. Various fault orientations and averages of the squared, absolute, and logarithmic radiation patterns have been considered. Effective radiation patterns combining high-frequency direct and surfacere-flected waves from shallow faults have also been derived and used in the computation of average radiation coefficients at teleseismic distances.
In most cases, the radiation coefficients are within a factor of 1.6 of the commonly used values of 0.52 and 0.63 for the rms of P - and S -wave radiation patterns, respectively, averaged over the whole focal sphere. The main exceptions to this conclusion are the coefficients for P waves at teleseismic distances from vertical strike-slip faults, which are at least a factor of 2.8 smaller than the commonly used value.
449 citations
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TL;DR: In this article, a GIS application, called So cia l V alues for E cosystem S ervices (SolVES), is developed to assess, map, and quantify the perceived social values of ecosystem services by deriving a non-monetary value index from responses to a public attitude and preference survey.
449 citations
Authors
Showing all 18026 results
Name | H-index | Papers | Citations |
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Derek R. Lovley | 168 | 582 | 95315 |
Steven Williams | 144 | 1375 | 86712 |
Thomas J. Smith | 140 | 1775 | 113919 |
Jillian F. Banfield | 127 | 562 | 60687 |
Kurunthachalam Kannan | 126 | 820 | 59886 |
J. D. Hansen | 122 | 975 | 76198 |
John P. Giesy | 114 | 1162 | 62790 |
David Pollard | 108 | 438 | 39550 |
Alan Cooper | 108 | 746 | 45772 |
Gordon E. Brown | 100 | 454 | 32152 |
Gerald Schubert | 98 | 614 | 34505 |
Peng Li | 95 | 1548 | 45198 |
Vipin Kumar | 95 | 614 | 59034 |
Susan E. Trumbore | 95 | 337 | 34844 |
Alfred S. McEwen | 92 | 624 | 28730 |