From November 1999 through July 2000, a broadband seismic experiment was carried out at Popocatépetl Volcano to record seismic activity over a wide period range (0.04–100 s). We present an overview of the seismicity recorded during this experiment and discuss results of analyses of long-period (LP) and very-long-period (VLP) seismic signals recorded at stations nearest to the crater over a four-month interval December 1999–March 2000. Three families of LP signals (Types-I, II, and III) are identified based on distinctive waveform features observed periods shorter than 1 s, periods longer than 15 s, and within the period range 0.5–2.5 s. Type-I LP events have impulsive first arrivals and exhibit a characteristic harmonic wave train with dominant periods in the 1.4–1.9 s range during the first 10 s of signal. These events are also associated with a remarkable VLP wavelet with period near 30 s. Type-II LP events represent pairs of events occurring in rapid succession and whose signatures are superimposed. These are typically marked by slowly emergent first arrivals and by a characteristic VLP wave train with dominant period near 30 s, made of two successive wavelets whose shapes are quasi-identical to those of the VLP wavelets associated with Type-I events. Type-III LP events represent the most energetic signals observed during our experiment. These have an emergent first arrival and display a harmonic signature with dominant period near 1.1 s. They are dominated by periods in the 0.25–0.35 s band and contain no significant energy at periods longer than 15 s. Hypocentral locations of the three types of LP events obtained from phase picks point to shallow seismic sources clustered at depths shallower than 2 km below the crater floor. Observed variations in volcanic eruptive activity correlate with defined LP families. Most of the observed seismicity consists of Type-I events that occur in association with 1–3-min-long degassing bursts (“exhalations”). Eruptive activity increased in intensity in February, coinciding with an increasing occurrence of Type-II LP events. Type-III events were first observed at the end of February and during March, in coincidence with the formation of a new lava dome. Vulcanian eruptions occurred in April and May. These events typically exhibit broadband signatures extending over the full period range of the sensors and lasting 30–80 min.
","language":"English","publisher":"Elsevier","doi":"10.1016/j.jvolgeores.2007.09.007","issn":"03770273","usgsCitation":"Arciniega-Ceballos, A., Chouet, B.A., Dawson, P., and Asch, G., 2008, Broadband seismic measurements of degassing activity associated with lava effusion at Popocatépetl Volcano, Mexico: Journal of Volcanology and Geothermal Research, v. 170, no. 1-2, p. 12-23, https://doi.org/10.1016/j.jvolgeores.2007.09.007.","productDescription":"12 p.","startPage":"12","endPage":"23","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":615,"text":"Volcano Hazards Program","active":true,"usgs":true},{"id":617,"text":"Volcano Science Center","active":true,"usgs":true}],"links":[{"id":242421,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":214675,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/j.jvolgeores.2007.09.007"}],"country":"Mexico","otherGeospatial":"Popocatepetl Volcano","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -98.68675231933594,\n 18.977727312447804\n ],\n [\n -98.68675231933594,\n 19.073799352002716\n ],\n [\n -98.55422973632812,\n 19.073799352002716\n ],\n [\n -98.55422973632812,\n 18.977727312447804\n ],\n [\n -98.68675231933594,\n 18.977727312447804\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"170","issue":"1-2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059f287e4b0c8380cd4b21b","contributors":{"authors":[{"text":"Arciniega-Ceballos, Alejandra","contributorId":57740,"corporation":false,"usgs":true,"family":"Arciniega-Ceballos","given":"Alejandra","affiliations":[],"preferred":false,"id":433727,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Chouet, Bernard A. 0000-0001-5527-0532 chouet@usgs.gov","orcid":"https://orcid.org/0000-0001-5527-0532","contributorId":3304,"corporation":false,"usgs":true,"family":"Chouet","given":"Bernard","email":"chouet@usgs.gov","middleInitial":"A.","affiliations":[{"id":617,"text":"Volcano Science Center","active":true,"usgs":true}],"preferred":true,"id":433729,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Dawson, Phillip","contributorId":95405,"corporation":false,"usgs":true,"family":"Dawson","given":"Phillip","affiliations":[],"preferred":false,"id":433728,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Asch, Guenter","contributorId":25374,"corporation":false,"usgs":true,"family":"Asch","given":"Guenter","email":"","affiliations":[],"preferred":false,"id":433726,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70031919,"text":"70031919 - 2008 - Eruption dynamics at Mount St. Helens imaged from broadband seismic waveforms: Interaction of the shallow magmatic and hydrothermal systems","interactions":[],"lastModifiedDate":"2019-04-04T10:19:11","indexId":"70031919","displayToPublicDate":"2008-01-01T00:00:00","publicationYear":"2008","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2314,"text":"Journal of Geophysical Research B: Solid Earth","active":true,"publicationSubtype":{"id":10}},"title":"Eruption dynamics at Mount St. Helens imaged from broadband seismic waveforms: Interaction of the shallow magmatic and hydrothermal systems","docAbstract":"The current eruption at Mount St. Helens is characterized by dome building and shallow, repetitive, long-period (LP) earthquakes. Waveform cross-correlation reveals remarkable similarity for a majority of the earthquakes over periods of several weeks. Stacked spectra of these events display multiple peaks between 0.5 and 2 Hz that are common to most stations. Lower-amplitude very-long-period (VLP) events commonly accompany the LP events. We model the source mechanisms of LP and VLP events in the 0.5-4 s and 8-40 s bands, respectively, using data recorded in July 2005 with a 19-station temporary broadband network. The source mechanism of the LP events includes: 1) a volumetric component modeled as resonance of a gently NNW-dipping, steam-filled crack located directly beneath the actively extruding part of the new dome and within 100 m of the crater floor and 2) a vertical single force attributed to movement of the overlying dome. The VLP source, which also includes volumetric and single-force components, is 250 m deeper and NNW of the LP source, at the SW edge of the 1980s lava dome. The volumetric component points to the compression and expansion of a shallow, magma-filled sill, which is subparallel to the hydrothermal crack imaged at the LP source, coupled with a smaller component of expansion and compression of a dike. The single-force components are due to mass advection in the magma conduit. The location, geometry and timing of the sources suggest the VLP and LP events are caused by perturbations of a common crack system.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Geophysical Research B: Solid Earth","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1029/2007JB005259","issn":"01480227","usgsCitation":"Waite, G., Chouet, B., and Dawson, P., 2008, Eruption dynamics at Mount St. Helens imaged from broadband seismic waveforms: Interaction of the shallow magmatic and hydrothermal systems: Journal of Geophysical Research B: Solid Earth, v. 113, no. 2, https://doi.org/10.1029/2007JB005259.","costCenters":[{"id":615,"text":"Volcano Hazards Program","active":true,"usgs":true}],"links":[{"id":476811,"rank":10000,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/2007jb005259","text":"Publisher Index Page"},{"id":242422,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":214676,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1029/2007JB005259"}],"volume":"113","issue":"2","noUsgsAuthors":false,"publicationDate":"2008-02-19","publicationStatus":"PW","scienceBaseUri":"505a0a4be4b0c8380cd522be","contributors":{"authors":[{"text":"Waite, G.P.","contributorId":82121,"corporation":false,"usgs":true,"family":"Waite","given":"G.P.","email":"","affiliations":[],"preferred":false,"id":433732,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Chouet, B. 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Hindcast simulations of bathymetric change in estuaries require daily sediment loads from major tributary rivers, to capture the episodic delivery of sediment during multi-day freshwater flow pulses. Two independent decadal sediment load estimates are available for the Sacramento/San Joaquin River Delta, California prior to 1959, but they must be downscaled to a daily interval for use in hindcast models. Daily flow and sediment load data to the Delta are available after 1930 and 1959, respectively, but bathymetric change simulations for San Francisco Bay prior to this require a method to generate daily sediment load estimates into the Delta. We used two historical proxies, monthly rainfall and unimpaired flow magnitudes, to generate monthly unimpaired flows to the Sacramento/San Joaquin Delta for the 1851-1929 period. This step generated the shape of the monthly hydrograph. These historical monthly flows were compared to unimpaired monthly flows from the modern era (1967-1987), and a least-squares metric selected a modern water year analogue for each historical water year. The daily hydrograph for the modern analogue was then assigned to the historical year and scaled to match the flow volume estimated by dendrochronology methods, providing the correct total flow for the year. We applied a sediment rating curve to this time-series of daily flows, to generate daily sediment loads for 1851-1958. The rating curve was calibrated with the two independent decadal sediment load estimates, over two distinct periods. This novel technique retained the timing and magnitude of freshwater flows and sediment loads, without damping variability or net sediment loads to San Francisco Bay. The time-series represents the hydraulic mining period with sustained periods of increased sediment loads, and a dramatic decrease after 1910, corresponding to a reduction in available mining debris. The analogue selection procedure also permits exploration of the morphological hydrograph concept, where a limited set of hydrographs is used to simulate the same bathymetric change as the actual set of hydrographs. The final daily sediment load time-series and morphological hydrograph concept will be applied as landward boundary conditions for hindcasting simulations of bathymetric change in San Francisco Bay.","largerWorkTitle":"Journal of Hydrology","language":"English","doi":"10.1016/j.jhydrol.2007.11.026","issn":"00221694","usgsCitation":"Ganju, N., Knowles, N., and Schoellhamer, D., 2008, Temporal downscaling of decadal sediment load estimates to a daily interval for use in hindcast simulations: Journal of Hydrology, v. 349, no. 3-4, p. 512-523, https://doi.org/10.1016/j.jhydrol.2007.11.026.","productDescription":"12 p.","startPage":"512","endPage":"523","costCenters":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true},{"id":678,"text":"Woods Hole Coastal and Marine Science Center","active":true,"usgs":true}],"links":[{"id":242454,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":" California","otherGeospatial":"Sacramento/San Joaquin River Delta","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -123.00292968749999,\n 40.329795743702064\n ],\n [\n -122.78320312499999,\n 39.99395569397331\n ],\n [\n -122.6513671875,\n 39.30029918615029\n ],\n [\n -122.40966796874999,\n 38.44498466889473\n ],\n [\n -121.81640624999999,\n 37.92686760148135\n ],\n [\n -121.48681640624999,\n 37.59682400108367\n ],\n [\n -121.37695312499999,\n 37.142803443716836\n ],\n [\n -120.9814453125,\n 36.527294814546245\n ],\n [\n -120.82763671875,\n 36.10237644873644\n ],\n [\n -120.56396484375,\n 35.567980458012094\n ],\n [\n -119.83886718750001,\n 34.939985151560435\n ],\n [\n -118.828125,\n 34.813803317113155\n ],\n [\n -118.6083984375,\n 35.17380831799959\n ],\n [\n -118.6083984375,\n 35.746512259918504\n ],\n [\n -118.71826171875,\n 36.29741818650811\n ],\n [\n -119.06982421874999,\n 36.82687474287728\n ],\n [\n -119.77294921874999,\n 37.405073750176925\n ],\n [\n -120.34423828125,\n 37.78808138412046\n ],\n [\n -120.76171875,\n 38.28993659801203\n ],\n [\n -121.46484375,\n 39.45316112807394\n ],\n [\n -121.6845703125,\n 39.842286020743394\n ],\n [\n -122.05810546875,\n 40.66397287638688\n ],\n [\n -122.36572265625,\n 40.81380923056958\n ],\n [\n -122.73925781250001,\n 40.56389453066509\n ],\n [\n -123.00292968749999,\n 40.329795743702064\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"349","issue":"3-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505ba509e4b08c986b32076d","contributors":{"authors":[{"text":"Ganju, N. 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We assessed sexual size dimorphism and developed a discriminant function to assign gender in Caspian Terns based on external morphology. We collected and measured Caspian Terns in San Francisco Bay, California, and confirmed their gender based on necropsy and genetic analysis. Of the eight morphological measurements we examined, only bill depth at the gonys and head plus bill length differed between males and females with males being larger than females. A discriminant function using both bill depth at the gonys and head plus bill length accurately assigned gender of 83% of terns for which gender was known. We improved the accuracy of our discriminant function to 90% by excluding individuals that had less than a 75% posterior probability of correctly being assigned to gender. Caspian Terns showed little sexual size dimorphism in many morphometries, but our results indicate they can be reliably assigned to gender in the field using two morphological measurements.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Wilson Journal of Ornithology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1676/07-061.1","issn":"15594491","usgsCitation":"Ackerman, J., Takekawa, J.Y., Bluso, J., Yee, J., and Eagles-Smith, C.A., 2008, Gender identification of Caspian Terns using external morphology and discriminant function analysis: Wilson Journal of Ornithology, v. 120, no. 2, p. 378-383, https://doi.org/10.1676/07-061.1.","startPage":"378","endPage":"383","numberOfPages":"6","costCenters":[],"links":[{"id":214707,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1676/07-061.1"},{"id":242455,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"120","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a14f4e4b0c8380cd54c3a","contributors":{"authors":[{"text":"Ackerman, Joshua T. 0000-0002-3074-8322 jackerman@usgs.gov","orcid":"https://orcid.org/0000-0002-3074-8322","contributorId":147078,"corporation":false,"usgs":true,"family":"Ackerman","given":"Joshua T.","email":"jackerman@usgs.gov","affiliations":[{"id":651,"text":"Western Ecological Research Center","active":true,"usgs":true}],"preferred":false,"id":433739,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Takekawa, John Y. 0000-0003-0217-5907 john_takekawa@usgs.gov","orcid":"https://orcid.org/0000-0003-0217-5907","contributorId":176168,"corporation":false,"usgs":true,"family":"Takekawa","given":"John","email":"john_takekawa@usgs.gov","middleInitial":"Y.","affiliations":[{"id":651,"text":"Western Ecological Research Center","active":true,"usgs":true}],"preferred":false,"id":433738,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Bluso, J.D.","contributorId":17033,"corporation":false,"usgs":true,"family":"Bluso","given":"J.D.","email":"","affiliations":[],"preferred":false,"id":433736,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Yee, J.L.","contributorId":25496,"corporation":false,"usgs":true,"family":"Yee","given":"J.L.","email":"","affiliations":[],"preferred":false,"id":433737,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Eagles-Smith, Collin A. 0000-0003-1329-5285 ceagles-smith@usgs.gov","orcid":"https://orcid.org/0000-0003-1329-5285","contributorId":505,"corporation":false,"usgs":true,"family":"Eagles-Smith","given":"Collin","email":"ceagles-smith@usgs.gov","middleInitial":"A.","affiliations":[{"id":518,"text":"Oregon Water Science Center","active":true,"usgs":true},{"id":290,"text":"Forest and Rangeland Ecosystem Science Center","active":false,"usgs":true},{"id":289,"text":"Forest and Rangeland Ecosys Science Center","active":true,"usgs":true}],"preferred":true,"id":433740,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":70031922,"text":"70031922 - 2008 - Evidence for fish dispersal from spatial analysis of stream network topology","interactions":[],"lastModifiedDate":"2012-03-12T17:21:27","indexId":"70031922","displayToPublicDate":"2008-01-01T00:00:00","publicationYear":"2008","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2564,"text":"Journal of the North American Benthological Society","onlineIssn":"1937-237X","printIssn":"0887-3593","active":true,"publicationSubtype":{"id":10}},"title":"Evidence for fish dispersal from spatial analysis of stream network topology","docAbstract":"Developing spatially explicit conservation strategies for stream fishes requires an understanding of the spatial structure of dispersal within stream networks. We explored spatial patterns of stream fish dispersal by evaluating how the size and proximity of connected streams (i.e., stream network topology) explained variation in fish assemblage structure and how this relationship varied with local stream size. We used data from the US Environmental Protection Agency's Environmental Monitoring and Assessment Program in wadeable streams of the Mid-Atlantic Highlands region (n = 308 sites). We quantified stream network topology with a continuous analysis based on the rate of downstream flow accumulation from sites and with a discrete analysis based on the presence of mainstem river confluences (i.e., basin area >250 km2) within 20 fluvial km (fkm) from sites. Continuous variation in stream network topology was related to local species richness within a distance of ???10 fkm, suggesting an influence of fish dispersal within this spatial grain. This effect was explained largely by catostomid species, cyprinid species, and riverine species, but was not explained by zoogeographic regions, ecoregions, sampling period, or spatial autocorrelation. Sites near mainstem river confluences supported greater species richness and abundance of catostomid, cyprinid, and ictalurid fishes than did sites >20 fkm from such confluences. Assemblages at sites on the smallest streams were not related to stream network topology, consistent with the hypothesis that local stream size regulates the influence of regional dispersal. These results demonstrate that the size and proximity of connected streams influence the spatial distribution of fish and suggest that these influences can be incorporated into the designs of stream bioassessments and reserves to enhance management efficacy. ?? 2008 by The North American Benthological Society.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of the North American Benthological Society","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1899/07-096.1","issn":"08873593","usgsCitation":"Hitt, N., and Angermeier, P., 2008, Evidence for fish dispersal from spatial analysis of stream network topology: Journal of the North American Benthological Society, v. 27, no. 2, p. 304-320, https://doi.org/10.1899/07-096.1.","startPage":"304","endPage":"320","numberOfPages":"17","costCenters":[],"links":[{"id":214741,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1899/07-096.1"},{"id":242491,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"27","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a0d3fe4b0c8380cd52ed5","contributors":{"authors":[{"text":"Hitt, N.P. 0000-0002-1046-4568","orcid":"https://orcid.org/0000-0002-1046-4568","contributorId":101466,"corporation":false,"usgs":true,"family":"Hitt","given":"N.P.","affiliations":[],"preferred":false,"id":433742,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Angermeier, P. L. 0000-0003-2864-170X","orcid":"https://orcid.org/0000-0003-2864-170X","contributorId":6410,"corporation":false,"usgs":true,"family":"Angermeier","given":"P. L.","affiliations":[],"preferred":false,"id":433741,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70032426,"text":"70032426 - 2008 - GSTARS computer models and their applications, Part II: Applications","interactions":[],"lastModifiedDate":"2012-03-12T17:21:21","indexId":"70032426","displayToPublicDate":"2008-01-01T00:00:00","publicationYear":"2008","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2072,"text":"International Journal of Sediment Research","active":true,"publicationSubtype":{"id":10}},"title":"GSTARS computer models and their applications, Part II: Applications","docAbstract":"In part 1 of this two-paper series, a brief summary of the basic concepts and theories used in developing the Generalized Stream Tube model for Alluvial River Simulation (GSTARS) computer models was presented. Part 2 provides examples that illustrate some of the capabilities of the GSTARS models and how they can be applied to solve a wide range of river and reservoir sedimentation problems. Laboratory and field case studies are used and the examples show representative applications of the earlier and of the more recent versions of GSTARS. Some of the more recent capabilities implemented in GSTARS3, one of the latest versions of the series, are also discussed here with more detail. ?? 2008 International Research and Training Centre on Erosion and Sedimentation and the World Association for Sedimentation and Erosion Research.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"International Journal of Sediment Research","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S1001-6279(09)60002-0","issn":"10016","usgsCitation":"Simoes, F., and Yang, C., 2008, GSTARS computer models and their applications, Part II: Applications: International Journal of Sediment Research, v. 23, no. 4, p. 299-315, https://doi.org/10.1016/S1001-6279(09)60002-0.","startPage":"299","endPage":"315","numberOfPages":"17","costCenters":[],"links":[{"id":213880,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S1001-6279(09)60002-0"},{"id":241546,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"23","issue":"4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a14a0e4b0c8380cd54ac3","contributors":{"authors":[{"text":"Simoes, F.J.M.","contributorId":100181,"corporation":false,"usgs":true,"family":"Simoes","given":"F.J.M.","email":"","affiliations":[],"preferred":false,"id":436105,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Yang, C.T.","contributorId":14629,"corporation":false,"usgs":true,"family":"Yang","given":"C.T.","email":"","affiliations":[],"preferred":false,"id":436104,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70032421,"text":"70032421 - 2008 - Projected long-term response of Southeastern birds to forest management","interactions":[],"lastModifiedDate":"2012-03-12T17:21:21","indexId":"70032421","displayToPublicDate":"2008-01-01T00:00:00","publicationYear":"2008","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1687,"text":"Forest Ecology and Management","active":true,"publicationSubtype":{"id":10}},"title":"Projected long-term response of Southeastern birds to forest management","docAbstract":"Numerous studies have explored the influence of forest management on avian communities empirically, but uncertainty about causal relationships between landscape patterns and temporal dynamics of bird communities calls into question how observed historical patterns can be projected into the future, particularly to assess consequences of differing management alternatives. We used the Habplan harvest scheduler to project forest conditions under several management scenarios mapped at 5-year time steps over a 40-year time span. We used empirical models of overall avian richness, richness of selected guilds, and probability of presence for selected species to predict avian community characteristics for each of the mapped landscapes generated for each 5-year time step for each management scenario. We then used time series analyses to quantify relationships between changes in avian community characteristics and management-induced changes to forest landscapes over time. Our models of avian community and species characteristics indicated habitat associations at multiple spatial scales, although landscape-level measures of habitat were generally more important than stand-level measures. Our projections showed overall avian richness, richness of Neotropical migrants, and the presence of Blue-gray Gnatcatchers and Eastern Wood-pewees varied little among management scenarios, corresponding closely to broad, overall landscape changes over time. By contrast, richness of canopy nesters, richness of cavity nesters, richness of scrub-successional associates, and the presence of Common Yellowthroats showed high temporal variability among management scenarios, likely corresponding to short-term, fine-scale changes in the landscape. Predicted temporal variability of both interior-forest and early successional birds was low in the unharvested landscape relative to that in the harvested landscape. Our results also suggested that early successional species can be sensitive to both availability and connectivity of habitat on the landscape. To increase or maintain the avian diversity, our projections indicate that forest managers need to consider landscape-scale configuration of stands, maintaining a spatially heterogeneous distribution of age classes. Our findings suggest which measures of richness or species presence may be appropriate indicators for monitoring effects of forest management on avian communities, depending on management objectives.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Forest Ecology and Management","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/j.foreco.2008.07.012","issn":"03781","usgsCitation":"Mitchell, M., Reynolds-Hogland, M.J., Smith, M., Wood, P., Beebe, J., Keyser, P., Loehle, C., Reynolds, C., Van Deusen, P., and White, D., 2008, Projected long-term response of Southeastern birds to forest management: Forest Ecology and Management, v. 256, no. 11, p. 1884-1896, https://doi.org/10.1016/j.foreco.2008.07.012.","startPage":"1884","endPage":"1896","numberOfPages":"13","costCenters":[],"links":[{"id":213815,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/j.foreco.2008.07.012"},{"id":241474,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"256","issue":"11","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a8ef9e4b0c8380cd7f4d6","contributors":{"authors":[{"text":"Mitchell, M.S.","contributorId":26724,"corporation":false,"usgs":true,"family":"Mitchell","given":"M.S.","email":"","affiliations":[],"preferred":false,"id":436078,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Reynolds-Hogland, M. J.","contributorId":57647,"corporation":false,"usgs":true,"family":"Reynolds-Hogland","given":"M.","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":436081,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Smith, M.L.","contributorId":35386,"corporation":false,"usgs":true,"family":"Smith","given":"M.L.","email":"","affiliations":[],"preferred":false,"id":436079,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Wood, P.B. 0000-0002-8575-1705","orcid":"https://orcid.org/0000-0002-8575-1705","contributorId":103992,"corporation":false,"usgs":true,"family":"Wood","given":"P.B.","affiliations":[],"preferred":false,"id":436086,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Beebe, J.A.","contributorId":58452,"corporation":false,"usgs":true,"family":"Beebe","given":"J.A.","email":"","affiliations":[],"preferred":false,"id":436082,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Keyser, P.D.","contributorId":20857,"corporation":false,"usgs":true,"family":"Keyser","given":"P.D.","email":"","affiliations":[],"preferred":false,"id":436077,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Loehle, C.","contributorId":92823,"corporation":false,"usgs":true,"family":"Loehle","given":"C.","email":"","affiliations":[],"preferred":false,"id":436085,"contributorType":{"id":1,"text":"Authors"},"rank":7},{"text":"Reynolds, C.J.","contributorId":69779,"corporation":false,"usgs":true,"family":"Reynolds","given":"C.J.","email":"","affiliations":[],"preferred":false,"id":436083,"contributorType":{"id":1,"text":"Authors"},"rank":8},{"text":"Van Deusen, P.","contributorId":37943,"corporation":false,"usgs":true,"family":"Van Deusen","given":"P.","affiliations":[],"preferred":false,"id":436080,"contributorType":{"id":1,"text":"Authors"},"rank":9},{"text":"White, D. Jr.","contributorId":81267,"corporation":false,"usgs":true,"family":"White","given":"D.","suffix":"Jr.","affiliations":[],"preferred":false,"id":436084,"contributorType":{"id":1,"text":"Authors"},"rank":10}]}} ,{"id":70031923,"text":"70031923 - 2008 - Are fractal dimensions of the spatial distribution of mineral deposits meaningful?","interactions":[],"lastModifiedDate":"2012-03-12T17:21:27","indexId":"70031923","displayToPublicDate":"2008-01-01T00:00:00","publicationYear":"2008","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2832,"text":"Natural Resources Research","onlineIssn":"1573-8981","printIssn":"1520-7439","active":true,"publicationSubtype":{"id":10}},"title":"Are fractal dimensions of the spatial distribution of mineral deposits meaningful?","docAbstract":"It has been proposed that the spatial distribution of mineral deposits is bifractal. An implication of this property is that the number of deposits in a permissive area is a function of the shape of the area. This is because the fractal density functions of deposits are dependent on the distance from known deposits. A long thin permissive area with most of the deposits in one end, such as the Alaskan porphyry permissive area, has a major portion of the area far from known deposits and consequently a low density of deposits associated with most of the permissive area. On the other hand, a more equi-dimensioned permissive area, such as the Arizona porphyry permissive area, has a more uniform density of deposits. Another implication of the fractal distribution is that the Poisson assumption typically used for estimating deposit numbers is invalid. Based on datasets of mineral deposits classified by type as inputs, the distributions of many different deposit types are found to have characteristically two fractal dimensions over separate non-overlapping spatial scales in the range of 5-1000 km. In particular, one typically observes a local dimension at spatial scales less than 30-60 km, and a regional dimension at larger spatial scales. The deposit type, geologic setting, and sample size influence the fractal dimensions. The consequence of the geologic setting can be diminished by using deposits classified by type. The crossover point between the two fractal domains is proportional to the median size of the deposit type. A plot of the crossover points for porphyry copper deposits from different geologic domains against median deposit sizes defines linear relationships and identifies regions that are significantly underexplored. Plots of the fractal dimension can also be used to define density functions from which the number of undiscovered deposits can be estimated. This density function is only dependent on the distribution of deposits and is independent of the definition of the permissive area. Density functions for porphyry copper deposits appear to be significantly different for regions in the Andes, Mexico, United States, and western Canada. Consequently, depending on which regional density function is used, quite different estimates of numbers of undiscovered deposits can be obtained. These fractal properties suggest that geologic studies based on mapping at scales of 1:24,000 to 1:100,000 may not recognize processes that are important in the formation of mineral deposits at scales larger than the crossover points at 30-60 km. ?? 2008 International Association for Mathematical Geology.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Natural Resources Research","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1007/s11053-008-9067-8","issn":"15207439","usgsCitation":"Raines, G.L., 2008, Are fractal dimensions of the spatial distribution of mineral deposits meaningful?: Natural Resources Research, v. 17, no. 2, p. 87-97, https://doi.org/10.1007/s11053-008-9067-8.","startPage":"87","endPage":"97","numberOfPages":"11","costCenters":[],"links":[{"id":242492,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":214742,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1007/s11053-008-9067-8"}],"volume":"17","issue":"2","noUsgsAuthors":false,"publicationDate":"2008-05-14","publicationStatus":"PW","scienceBaseUri":"5059ed5be4b0c8380cd4976a","contributors":{"authors":[{"text":"Raines, G. L.","contributorId":90720,"corporation":false,"usgs":true,"family":"Raines","given":"G.","middleInitial":"L.","affiliations":[],"preferred":false,"id":433743,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70031924,"text":"70031924 - 2008 - Representing general theoretical concepts in structural equation models: The role of composite variables","interactions":[],"lastModifiedDate":"2012-03-12T17:21:27","indexId":"70031924","displayToPublicDate":"2008-01-01T00:00:00","publicationYear":"2008","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1573,"text":"Environmental and Ecological Statistics","active":true,"publicationSubtype":{"id":10}},"title":"Representing general theoretical concepts in structural equation models: The role of composite variables","docAbstract":"Structural equation modeling (SEM) holds the promise of providing natural scientists the capacity to evaluate complex multivariate hypotheses about ecological systems. Building on its predecessors, path analysis and factor analysis, SEM allows for the incorporation of both observed and unobserved (latent) variables into theoretically-based probabilistic models. In this paper we discuss the interface between theory and data in SEM and the use of an additional variable type, the composite. In simple terms, composite variables specify the influences of collections of other variables and can be helpful in modeling heterogeneous concepts of the sort commonly of interest to ecologists. While long recognized as a potentially important element of SEM, composite variables have received very limited use, in part because of a lack of theoretical consideration, but also because of difficulties that arise in parameter estimation when using conventional solution procedures. In this paper we present a framework for discussing composites and demonstrate how the use of partially-reduced-form models can help to overcome some of the parameter estimation and evaluation problems associated with models containing composites. Diagnostic procedures for evaluating the most appropriate and effective use of composites are illustrated with an example from the ecological literature. It is argued that an ability to incorporate composite variables into structural equation models may be particularly valuable in the study of natural systems, where concepts are frequently multifaceted and the influence of suites of variables are often of interest. ?? Springer Science+Business Media, LLC 2007.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Environmental and Ecological Statistics","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1007/s10651-007-0047-7","issn":"13528505","usgsCitation":"Grace, J., and Bollen, K., 2008, Representing general theoretical concepts in structural equation models: The role of composite variables: Environmental and Ecological Statistics, v. 15, no. 2, p. 191-213, https://doi.org/10.1007/s10651-007-0047-7.","startPage":"191","endPage":"213","numberOfPages":"23","costCenters":[],"links":[{"id":214773,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1007/s10651-007-0047-7"},{"id":242523,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"15","issue":"2","noUsgsAuthors":false,"publicationDate":"2007-10-23","publicationStatus":"PW","scienceBaseUri":"505aa883e4b0c8380cd8594e","contributors":{"authors":[{"text":"Grace, J.B. 0000-0001-6374-4726","orcid":"https://orcid.org/0000-0001-6374-4726","contributorId":38938,"corporation":false,"usgs":true,"family":"Grace","given":"J.B.","affiliations":[],"preferred":false,"id":433745,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Bollen, K.A.","contributorId":35143,"corporation":false,"usgs":true,"family":"Bollen","given":"K.A.","email":"","affiliations":[],"preferred":false,"id":433744,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70031926,"text":"70031926 - 2008 - Comparative study of transport processes of nitrogen, phosphorus, and herbicides to streams in five agricultural basins, USA","interactions":[],"lastModifiedDate":"2021-05-27T14:42:48.514946","indexId":"70031926","displayToPublicDate":"2008-01-01T00:00:00","publicationYear":"2008","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2262,"text":"Journal of Environmental Quality","active":true,"publicationSubtype":{"id":10}},"title":"Comparative study of transport processes of nitrogen, phosphorus, and herbicides to streams in five agricultural basins, USA","docAbstract":"Agricultural chemical transport to surface water and the linkage to other hydrological compartments, principally ground water, was investigated at five watersheds in semiarid to humid climatic settings. Chemical transport was affected by storm water runoff, soil drainage, irrigation, and how streams were linked to shallow ground water systems. Irrigation practices and timing of chemical use greatly affected nutrient and pesticide transport in the semiarid basins. Irrigation with imported water tended to increase ground water and chemical transport, whereas the use of locally pumped irrigation water may eliminate connections between streams and ground water, resulting in lower annual loads. Drainage pathways in humid environments are important because the loads may be transported in tile drains, or through varying combinations of ground water discharge, and overland flow. In most cases, overland flow contributed the greatest loads, but a significant portion of the annual load of nitrate and some pesticide degradates can be transported under base-flow conditions. The highest basin yields for nitrate were measured in a semiarid irrigated system that used imported water and in a stream dominated by tile drainage in a humid environment. Pesticide loads, as a percent of actual use (LAPU), showed the effects of climate and geohydrologic conditions. The LAPU values in the semiarid study basin in Washington were generally low because most of the load was transported in ground water discharge to the stream. When herbicides are applied during the rainy season in a semiarid setting, such as simazine in the California basin, LAPU values are similar to those in the Midwest basins. Copyright ?? 2008 by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America. All rights reserved.","language":"English","publisher":"ACSESS","doi":"10.2134/jeq2007.0408","issn":"00472425","usgsCitation":"Domagalski, J.L., Ator, S., Coupe, R., McCarthy, K., Lampe, D., Sandstrom, M.W., and Baker, N., 2008, Comparative study of transport processes of nitrogen, phosphorus, and herbicides to streams in five agricultural basins, USA: Journal of Environmental Quality, v. 37, no. 3, p. 1158-1169, https://doi.org/10.2134/jeq2007.0408.","productDescription":"12 p.","startPage":"1158","endPage":"1169","numberOfPages":"12","costCenters":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true},{"id":452,"text":"National Water Quality Laboratory","active":true,"usgs":true}],"links":[{"id":242558,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"37","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059f82ae4b0c8380cd4cf01","contributors":{"authors":[{"text":"Domagalski, Joseph L. 0000-0002-6032-757X joed@usgs.gov","orcid":"https://orcid.org/0000-0002-6032-757X","contributorId":1330,"corporation":false,"usgs":true,"family":"Domagalski","given":"Joseph","email":"joed@usgs.gov","middleInitial":"L.","affiliations":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true}],"preferred":true,"id":433753,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Ator, S. 0000-0002-9186-4837","orcid":"https://orcid.org/0000-0002-9186-4837","contributorId":59645,"corporation":false,"usgs":true,"family":"Ator","given":"S.","affiliations":[],"preferred":false,"id":433755,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Coupe, R.","contributorId":11841,"corporation":false,"usgs":true,"family":"Coupe","given":"R.","email":"","affiliations":[],"preferred":false,"id":433751,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"McCarthy, K.","contributorId":48287,"corporation":false,"usgs":true,"family":"McCarthy","given":"K.","affiliations":[],"preferred":false,"id":433754,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Lampe, D.","contributorId":96105,"corporation":false,"usgs":true,"family":"Lampe","given":"D.","email":"","affiliations":[],"preferred":false,"id":433757,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Sandstrom, Mark W. 0000-0003-0006-5675 sandstro@usgs.gov","orcid":"https://orcid.org/0000-0003-0006-5675","contributorId":706,"corporation":false,"usgs":true,"family":"Sandstrom","given":"Mark","email":"sandstro@usgs.gov","middleInitial":"W.","affiliations":[{"id":5046,"text":"Branch of Analytical Serv (NWQL)","active":true,"usgs":true},{"id":503,"text":"Office of Water Quality","active":true,"usgs":true},{"id":37464,"text":"WMA - Laboratory & Analytical Services Division","active":true,"usgs":true},{"id":452,"text":"National Water Quality Laboratory","active":true,"usgs":true}],"preferred":true,"id":433756,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Baker, N.","contributorId":37975,"corporation":false,"usgs":true,"family":"Baker","given":"N.","email":"","affiliations":[],"preferred":false,"id":433752,"contributorType":{"id":1,"text":"Authors"},"rank":7}]}} ,{"id":70031928,"text":"70031928 - 2008 - Efficacy of algal metrics for assessing nutrient and organic enrichment in flowing waters","interactions":[],"lastModifiedDate":"2016-05-30T13:21:07","indexId":"70031928","displayToPublicDate":"2008-01-01T00:00:00","publicationYear":"2008","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1696,"text":"Freshwater Biology","active":true,"publicationSubtype":{"id":10}},"title":"Efficacy of algal metrics for assessing nutrient and organic enrichment in flowing waters","docAbstract":"1. Algal-community metrics were calculated for periphyton samples collected from 976 streams and rivers by the U.S. Geological Survey’s National Water-Quality Assessment (NAWQA) Programme during 1993–2001 to evaluate national and regional relations with water chemistry and to compare whether algal-metric values differ significantly among undeveloped and developed land-use classifications.
\n2. Algal metrics with significant positive correlations with nutrient concentrations included indicators of trophic condition, organic enrichment, salinity, motility and taxa richness. The relative abundance of nitrogen-fixing algae was negatively correlated with nitrogen concentrations, and the abundance of diatom species associated with high dissolved oxygen concentrations was negatively correlated with both nitrogen and phosphorus concentrations. Median algal-metric values and nutrient concentrations were significantly lower at undeveloped sites than those draining agricultural or urban catchments.
\n3. Total algal biovolume did not differ significantly among major river catchments or land-use classifications, and was only weakly correlated with nitrate (positive) and suspended-sediment (negative) concentrations. Estimates of periphyton chlorophyll a indicated an oligotrophic–mesotrophic boundary of about 21 mg m−2 and a mesotrophic–eutrophic boundary of about 55 mg m−2 based on upper and lower quartiles of the biovolume data distribution.
\n4. Although algal species tolerance to nutrient and organic enrichment is well documented, additional taxonomic and autecological research on sensitive, endemic algal species would further enhance water-quality assessments.
","language":"English","publisher":"Wiley","doi":"10.1111/j.1365-2427.2007.01951.x","issn":"00465070","usgsCitation":"Porter, S.D., Mueller, D., Spahr, N., Munn, M., and Dubrovsky, N., 2008, Efficacy of algal metrics for assessing nutrient and organic enrichment in flowing waters: Freshwater Biology, v. 53, no. 5, p. 1036-1054, https://doi.org/10.1111/j.1365-2427.2007.01951.x.","productDescription":"19 p.","startPage":"1036","endPage":"1054","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":622,"text":"Washington Water Science Center","active":true,"usgs":true}],"links":[{"id":242592,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":214840,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1111/j.1365-2427.2007.01951.x"}],"volume":"53","issue":"5","noUsgsAuthors":false,"publicationDate":"2008-01-13","publicationStatus":"PW","scienceBaseUri":"505a0856e4b0c8380cd51aa4","contributors":{"authors":[{"text":"Porter, S. D.","contributorId":8882,"corporation":false,"usgs":true,"family":"Porter","given":"S.","email":"","middleInitial":"D.","affiliations":[],"preferred":false,"id":433764,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Mueller, D. K.","contributorId":93525,"corporation":false,"usgs":true,"family":"Mueller","given":"D. K.","affiliations":[],"preferred":false,"id":433768,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Spahr, N.E.","contributorId":79476,"corporation":false,"usgs":true,"family":"Spahr","given":"N.E.","email":"","affiliations":[],"preferred":false,"id":433767,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Munn, M.D.","contributorId":77908,"corporation":false,"usgs":true,"family":"Munn","given":"M.D.","email":"","affiliations":[],"preferred":false,"id":433766,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Dubrovsky, N. M.","contributorId":48199,"corporation":false,"usgs":true,"family":"Dubrovsky","given":"N. M.","affiliations":[],"preferred":false,"id":433765,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":70031936,"text":"70031936 - 2008 - Density currents in the Chicago River: Characterization, effects on water quality, and potential sources","interactions":[],"lastModifiedDate":"2012-03-12T17:21:26","indexId":"70031936","displayToPublicDate":"2008-01-01T00:00:00","publicationYear":"2008","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3352,"text":"Science of the Total Environment","active":true,"publicationSubtype":{"id":10}},"title":"Density currents in the Chicago River: Characterization, effects on water quality, and potential sources","docAbstract":"Bidirectional flows in a river system can occur under stratified flow conditions and in addition to creating significant errors in discharge estimates, the upstream propagating currents are capable of transporting contaminants and affecting water quality. Detailed field observations of bidirectional flows were made in the Chicago River in Chicago, Illinois in the winter of 2005-06. Using multiple acoustic Doppler current profilers simultaneously with a water-quality profiler, the formation of upstream propagating density currents within the Chicago River both as an underflow and an overflow was observed on three occasions. Density differences driving the flow primarily arise from salinity differences between intersecting branches of the Chicago River, whereas water temperature is secondary in the creation of these currents. Deicing salts appear to be the primary source of salinity in the North Branch of the Chicago River, entering the waterway through direct runoff and effluent from a wastewater-treatment plant in a large metropolitan area primarily served by combined sewers. Water-quality assessments of the Chicago River may underestimate (or overestimate) the impairment of the river because standard water-quality monitoring practices do not account for density-driven underflows (or overflows). Chloride concentrations near the riverbed can significantly exceed concentrations at the river surface during underflows indicating that full-depth parameter profiles are necessary for accurate water-quality assessments in urban environments where application of deicing salt is common.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Science of the Total Environment","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/j.scitotenv.2008.04.011","issn":"00489697","usgsCitation":"Jackson, P., Garcia, C., Oberg, K.A., Johnson, K., and Garcia, M., 2008, Density currents in the Chicago River: Characterization, effects on water quality, and potential sources: Science of the Total Environment, v. 401, no. 1-3, p. 130-143, https://doi.org/10.1016/j.scitotenv.2008.04.011.","startPage":"130","endPage":"143","numberOfPages":"14","costCenters":[],"links":[{"id":476769,"rank":10000,"type":{"id":41,"text":"Open Access External Repository Page"},"url":"https://hdl.handle.net/1912/2250","text":"External Repository"},{"id":214993,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/j.scitotenv.2008.04.011"},{"id":242755,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"401","issue":"1-3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059fea4e4b0c8380cd4ee40","contributors":{"authors":[{"text":"Jackson, P.R.","contributorId":68552,"corporation":false,"usgs":true,"family":"Jackson","given":"P.R.","email":"","affiliations":[],"preferred":false,"id":433792,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Garcia, C.M.","contributorId":84159,"corporation":false,"usgs":true,"family":"Garcia","given":"C.M.","email":"","affiliations":[],"preferred":false,"id":433794,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Oberg, K. A.","contributorId":67553,"corporation":false,"usgs":true,"family":"Oberg","given":"K.","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":433791,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Johnson, K. K.","contributorId":70871,"corporation":false,"usgs":true,"family":"Johnson","given":"K. K.","affiliations":[],"preferred":false,"id":433793,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Garcia, M.H.","contributorId":45079,"corporation":false,"usgs":true,"family":"Garcia","given":"M.H.","email":"","affiliations":[],"preferred":false,"id":433790,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":70031937,"text":"70031937 - 2008 - Rainfall effects on rare annual plants","interactions":[],"lastModifiedDate":"2017-01-04T11:05:08","indexId":"70031937","displayToPublicDate":"2008-01-01T00:00:00","publicationYear":"2008","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2242,"text":"Journal of Ecology","active":true,"publicationSubtype":{"id":10}},"title":"Rainfall effects on rare annual plants","docAbstract":"No abstract available.
","language":"English","publisher":"American Geological Institute","usgsCitation":"O'Connor, J., Major, J.J., and Grant, G., 2008, The dams come down: Unchaining U.S. Rivers: Geotimes, v. 53, no. 3, p. 22-28.","productDescription":"7 p.","startPage":"22","endPage":"28","numberOfPages":"7","costCenters":[{"id":615,"text":"Volcano Hazards Program","active":true,"usgs":true}],"links":[{"id":242390,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"53","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505baa7de4b08c986b32285d","contributors":{"authors":[{"text":"O'Connor, J.","contributorId":49586,"corporation":false,"usgs":true,"family":"O'Connor","given":"J.","affiliations":[],"preferred":false,"id":433833,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Major, Jon J. 0000-0003-2449-4466 jjmajor@usgs.gov","orcid":"https://orcid.org/0000-0003-2449-4466","contributorId":439,"corporation":false,"usgs":true,"family":"Major","given":"Jon","email":"jjmajor@usgs.gov","middleInitial":"J.","affiliations":[{"id":617,"text":"Volcano Science Center","active":true,"usgs":true}],"preferred":true,"id":433834,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Grant, G.","contributorId":35966,"corporation":false,"usgs":true,"family":"Grant","given":"G.","affiliations":[],"preferred":false,"id":433832,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70031946,"text":"70031946 - 2008 - Scientific and public responses to the ongoing volcanic crisis at Popocatépetl Volcano, Mexico: Importance of an effective hazards-warning system","interactions":[],"lastModifiedDate":"2019-03-06T10:12:05","indexId":"70031946","displayToPublicDate":"2008-01-01T00:00:00","publicationYear":"2008","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2499,"text":"Journal of Volcanology and Geothermal Research","active":true,"publicationSubtype":{"id":10}},"title":"Scientific and public responses to the ongoing volcanic crisis at Popocatépetl Volcano, Mexico: Importance of an effective hazards-warning system","docAbstract":"Volcanic eruptions and other potentially hazardous natural phenomena occur independently of any human actions. However, such phenomena can cause disasters when a society fails to foresee the hazardous manifestations and adopt adequate measures to reduce its vulnerability. One of the causes of such a failure is the lack of a consistent perception of the changing hazards posed by an ongoing eruption, i.e., with members of the scientific community, the Civil Protection authorities and the general public having diverging notions about what is occurring and what may happen. The problem of attaining a perception of risk as uniform as possible in a population measured in millions during an evolving eruption requires searching for communication tools that can describe—as simply as possible—the relations between the level of threat posed by the volcano, and the level of response of the authorities and the public. The hazards-warning system adopted at Popocatépetl Volcano, called the Volcanic Traffic Light Alert System(VTLAS), is a basic communications protocol that translates volcano threat into seven levels of preparedness for the emergency-management authorities, but only three levels of alert for the public (color coded green–yellow–red). The changing status of the volcano threat is represented as the most likely scenarios according to the opinions of an official scientific committee analyzing all available data. The implementation of the VTLAS was intended to reduce the possibility of ambiguous interpretations of intermediate levels by the endangered population. Although the VTLAS is imperfect and has not solved all problems involved in mass communication and decision-making during a volcanic crisis, it marks a significant advance in the management of volcanic crises in Mexico.
","language":"English","publisher":"Elsevier","doi":"10.1016/j.jvolgeores.2007.09.002","issn":"03770273","usgsCitation":"De la Cruz-Reyna, S., and Tilling, R.I., 2008, Scientific and public responses to the ongoing volcanic crisis at Popocatépetl Volcano, Mexico: Importance of an effective hazards-warning system: Journal of Volcanology and Geothermal Research, v. 170, no. 1-2, p. 121-134, https://doi.org/10.1016/j.jvolgeores.2007.09.002.","productDescription":"14 p.","startPage":"121","endPage":"134","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":615,"text":"Volcano Hazards Program","active":true,"usgs":true}],"links":[{"id":242423,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":214677,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/j.jvolgeores.2007.09.002"}],"country":"Mexico","otherGeospatial":"Popocatepetl Volcano","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -98.68675231933594,\n 18.977727312447804\n ],\n [\n -98.68675231933594,\n 19.073799352002716\n ],\n [\n -98.55422973632812,\n 19.073799352002716\n ],\n [\n -98.55422973632812,\n 18.977727312447804\n ],\n [\n -98.68675231933594,\n 18.977727312447804\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"170","issue":"1-2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b8780e4b08c986b3164ff","contributors":{"authors":[{"text":"De la Cruz-Reyna, Servando","contributorId":67650,"corporation":false,"usgs":true,"family":"De la Cruz-Reyna","given":"Servando","email":"","affiliations":[],"preferred":false,"id":433835,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Tilling, Robert I. 0000-0003-4263-7221 rtilling@usgs.gov","orcid":"https://orcid.org/0000-0003-4263-7221","contributorId":2567,"corporation":false,"usgs":true,"family":"Tilling","given":"Robert","email":"rtilling@usgs.gov","middleInitial":"I.","affiliations":[],"preferred":true,"id":433836,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70031949,"text":"70031949 - 2008 - Ecological community integration increases with added trophic complexity","interactions":[],"lastModifiedDate":"2017-04-03T12:38:56","indexId":"70031949","displayToPublicDate":"2008-01-01T00:00:00","publicationYear":"2008","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1452,"text":"Ecological Complexity","active":true,"publicationSubtype":{"id":10}},"title":"Ecological community integration increases with added trophic complexity","docAbstract":"The existence of functional biological organization at the level of multi-species communities has long been contested in ecology and evolutionary biology. I found that adding a trophic level to simulated ecological communities enhanced their ability to compete at the community level, increasing the likelihood of one community forcing all or most species in a second community to extinction. Community-level identity emerged within systems of interacting ecological networks, while competitive ability at the community level was enhanced by intense within-community selection pressure. These results suggest a reassessment of the nature of biological organization above the level of species, indicating that the drive toward biological integration, so prominent throughout the history of life, might extend to multi-species communities.
","language":"English","publisher":"Elsevier","doi":"10.1016/j.ecocom.2007.10.004","issn":"1476945X","usgsCitation":"Wright, C.K., 2008, Ecological community integration increases with added trophic complexity: Ecological Complexity, v. 5, no. 2, p. 140-145, https://doi.org/10.1016/j.ecocom.2007.10.004.","productDescription":"6 p.","startPage":"140","endPage":"145","numberOfPages":"6","costCenters":[{"id":222,"text":"Earth Resources Observation and Science (EROS) Center","active":true,"usgs":true}],"links":[{"id":242457,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":214709,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/j.ecocom.2007.10.004"}],"volume":"5","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a054ae4b0c8380cd50d32","contributors":{"authors":[{"text":"Wright, Christopher K.","contributorId":45566,"corporation":false,"usgs":true,"family":"Wright","given":"Christopher","email":"","middleInitial":"K.","affiliations":[],"preferred":false,"id":433846,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70031950,"text":"70031950 - 2008 - Coal and cremation at the Tschudi burn, Chan Chan, Northern Peru","interactions":[],"lastModifiedDate":"2012-03-12T17:21:28","indexId":"70031950","displayToPublicDate":"2008-01-01T00:00:00","publicationYear":"2008","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":881,"text":"Archaeometry","active":true,"publicationSubtype":{"id":10}},"title":"Coal and cremation at the Tschudi burn, Chan Chan, Northern Peru","docAbstract":"Analyses of a 20-30 cm thick, completely combusted ash at the 25 ?? 70 m Tschudi burn at Chan Chan, northern Peru??, contain 52-55 wt% SiO2, 180-210 ppm zirconium and are consistent with coal ash. Soil geochemistry across the burn showed elevated calcium and phosphorus content, possible evidence for reported human cremation. A calcined, 5 g, 4.5 cm skull fragment recovered from the burn was confirmed as human by protein radioimmunoassay (pRIA). X-ray diffraction showed that the bone had been heated to 520??C. The burn took place c. ad 1312-1438 based on interpretation of a 14C date on carbonized plant tinder. ?? 2008 University of Oxford.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Archaeometry","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1111/j.1475-4754.2007.00358.x","issn":"0003813X","usgsCitation":"Brooks, W.E., Galvez, M.C., Jackson, J., McGeehin, J., and Hood, D., 2008, Coal and cremation at the Tschudi burn, Chan Chan, Northern Peru: Archaeometry, v. 50, no. 3, p. 495-515, https://doi.org/10.1111/j.1475-4754.2007.00358.x.","startPage":"495","endPage":"515","numberOfPages":"21","costCenters":[],"links":[{"id":214710,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1111/j.1475-4754.2007.00358.x"},{"id":242458,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"50","issue":"3","noUsgsAuthors":false,"publicationDate":"2007-12-06","publicationStatus":"PW","scienceBaseUri":"5059f67fe4b0c8380cd4c7cc","contributors":{"authors":[{"text":"Brooks, W. E.","contributorId":90716,"corporation":false,"usgs":true,"family":"Brooks","given":"W.","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":433849,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Galvez, Mora C.","contributorId":80097,"corporation":false,"usgs":true,"family":"Galvez","given":"Mora","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":433848,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Jackson, J.C.","contributorId":104503,"corporation":false,"usgs":true,"family":"Jackson","given":"J.C.","email":"","affiliations":[],"preferred":false,"id":433851,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"McGeehin, J. P. 0000-0002-5320-6091","orcid":"https://orcid.org/0000-0002-5320-6091","contributorId":48593,"corporation":false,"usgs":true,"family":"McGeehin","given":"J. P.","affiliations":[],"preferred":false,"id":433847,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Hood, D.G.","contributorId":98556,"corporation":false,"usgs":true,"family":"Hood","given":"D.G.","email":"","affiliations":[],"preferred":false,"id":433850,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":70031952,"text":"70031952 - 2008 - Rapid formation of hyperpycnal sediment gravity currents offshore of a semi-arid California river","interactions":[],"lastModifiedDate":"2012-03-12T17:21:27","indexId":"70031952","displayToPublicDate":"2008-01-01T00:00:00","publicationYear":"2008","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1333,"text":"Continental Shelf Research","active":true,"publicationSubtype":{"id":10}},"title":"Rapid formation of hyperpycnal sediment gravity currents offshore of a semi-arid California river","docAbstract":"Observations of sediment dispersal from the Santa Clara River of southern California during two moderately sized river discharge events suggest that river sediment rapidly formed a negatively buoyant (hyperpycnal) bottom plume along the seabed within hours of peak discharge. An array of acoustic and optical sensors were placed at three stations 1 km from the Santa Clara River mouth in 10-m water depth during January-February 2004. These combined observations suggest that fluid mud concentrations of suspended sediment (>10 g/l) and across-shore gravity currents (???5 cm/s) were observed in the lower 20-40 cm of the water column 4-6 h after discharge events. Gravity currents were wave dominated, rather than auto-suspending, and appeared to consist of silt-to-clay sized sediment from the river. Sediment mass balances suggest that 25-50% of the discharged river sediment was transported by these hyperpycnal currents. Sediment settling purely by flocs (???1 mm/s) cannot explain the formation of the observed hyperpycnal plumes, therefore we suggest that some enhanced sediment settling from mixing, convective instabilities, or diverging plumes occurred that would explain the formation of the gravity currents. These combined results provide field evidence that high suspended-sediment concentrations from rivers (>1 g/l) may rapidly form hyperpycnal sediment gravity currents immediately offshore of river mouths, and these pathways can explain a significant portion of the river-margin sediment budget. The fate of this sediment will be strongly influenced by bathymetry, whereas the fate of the remaining sediment will be much more influenced by ocean currents.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Continental Shelf Research","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/j.csr.2007.11.002","issn":"02784343","usgsCitation":"Warrick, J., Xu, J., Noble, M., and Lee, H., 2008, Rapid formation of hyperpycnal sediment gravity currents offshore of a semi-arid California river: Continental Shelf Research, v. 28, no. 8, p. 991-1009, https://doi.org/10.1016/j.csr.2007.11.002.","startPage":"991","endPage":"1009","numberOfPages":"19","costCenters":[],"links":[{"id":242494,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":214744,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/j.csr.2007.11.002"}],"volume":"28","issue":"8","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a94e3e4b0c8380cd8169a","contributors":{"authors":[{"text":"Warrick, J.A.","contributorId":53503,"corporation":false,"usgs":true,"family":"Warrick","given":"J.A.","affiliations":[],"preferred":false,"id":433858,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Xu, J.","contributorId":25324,"corporation":false,"usgs":true,"family":"Xu","given":"J.","affiliations":[],"preferred":false,"id":433857,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Noble, M.A.","contributorId":93513,"corporation":false,"usgs":true,"family":"Noble","given":"M.A.","email":"","affiliations":[],"preferred":false,"id":433859,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Lee, H.J.","contributorId":96693,"corporation":false,"usgs":true,"family":"Lee","given":"H.J.","email":"","affiliations":[],"preferred":false,"id":433860,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70031953,"text":"70031953 - 2008 - Application of multiple isotopic and geochemical tracers for investigation of recharge, salinization, and residence time of water in the Souss-Massa aquifer, southwest of Morocco","interactions":[],"lastModifiedDate":"2012-03-12T17:21:27","indexId":"70031953","displayToPublicDate":"2008-01-01T00:00:00","publicationYear":"2008","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2342,"text":"Journal of Hydrology","active":true,"publicationSubtype":{"id":10}},"title":"Application of multiple isotopic and geochemical tracers for investigation of recharge, salinization, and residence time of water in the Souss-Massa aquifer, southwest of Morocco","docAbstract":"Groundwater and surface water in Souss-Massa basin in the west-southern part of Morocco is characterized by a large variation in salinity, up to levels of 37 g L-1. The high salinity coupled with groundwater level decline pose serious problems for current irrigation and domestic water supplies as well as future exploitation. A combined hydrogeologic and isotopic investigation using several chemical and isotopic tracers such as Br/Cl, ??18O, ??2H, 3H, 87Sr/86Sr, ??11B, and 14C was carried out in order to determine the sources of water recharge to the aquifer, the origin of salinity, and the residence time of water. Stable isotope, 3H and 14C data indicate that the high Atlas mountains in the northern margin of the Souss-Massa basin with high rainfall and low ??18O and ??2H values (-6 to -8??? and -36 to -50???) is currently constitute the major source of recharge to the Souss-Massa shallow aquifer, particularly along the eastern part of the basin. Localized stable isotope enrichments offset meteoric isotopic signature and are associated with high nitrate concentrations, which infer water recycling via water agricultural return flows. The 3H and 14C data suggest that the residence time of water in the western part of the basin is in the order of several thousands of years; hence old water is mined, particularly in the coastal areas. The multiple isotope analyses and chemical tracing of groundwater from the basin reveal that seawater intrusion is just one of multiple salinity sources that affect the quality of groundwater in the Souss-Massa aquifer. We differentiate between modern seawater intrusion, salinization by remnants of seawater entrapped in the middle Souss plains, recharge of nitrate-rich agricultural return flow, and dissolution of evaporate rocks (gypsum and halite minerals) along the outcrops of the high Atlas mountains. The data generated in this study provide the framework for a comprehensive management plan in which water exploitation should shift toward the eastern part of the basin where current recharge occurs with young and high quality groundwater. In contrast, we argued that the heavily exploited aquifer along the coastal areas is more vulnerable given the relatively longer residence time of the water and salinization processes in this part of the aquifer. ?? 2008 Elsevier B.V. All rights reserved.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Hydrology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/j.jhydrol.2008.01.022","issn":"00221694","usgsCitation":"Bouchaou, L., Michelot, J., Vengosh, A., Hsissou, Y., Qurtobi, M., Gaye, C., Bullen, T., and Zuppi, G., 2008, Application of multiple isotopic and geochemical tracers for investigation of recharge, salinization, and residence time of water in the Souss-Massa aquifer, southwest of Morocco: Journal of Hydrology, v. 352, no. 3-4, p. 267-287, https://doi.org/10.1016/j.jhydrol.2008.01.022.","startPage":"267","endPage":"287","numberOfPages":"21","costCenters":[],"links":[{"id":214775,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/j.jhydrol.2008.01.022"},{"id":242525,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"352","issue":"3-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059eca8e4b0c8380cd493fa","contributors":{"authors":[{"text":"Bouchaou, L.","contributorId":51556,"corporation":false,"usgs":true,"family":"Bouchaou","given":"L.","affiliations":[],"preferred":false,"id":433862,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Michelot, J.L.","contributorId":58483,"corporation":false,"usgs":true,"family":"Michelot","given":"J.L.","affiliations":[],"preferred":false,"id":433864,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Vengosh, A.","contributorId":88925,"corporation":false,"usgs":true,"family":"Vengosh","given":"A.","affiliations":[],"preferred":false,"id":433868,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Hsissou, Y.","contributorId":22596,"corporation":false,"usgs":true,"family":"Hsissou","given":"Y.","email":"","affiliations":[],"preferred":false,"id":433861,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Qurtobi, M.","contributorId":78957,"corporation":false,"usgs":true,"family":"Qurtobi","given":"M.","email":"","affiliations":[],"preferred":false,"id":433866,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Gaye, C.B.","contributorId":56017,"corporation":false,"usgs":true,"family":"Gaye","given":"C.B.","email":"","affiliations":[],"preferred":false,"id":433863,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Bullen, T.D.","contributorId":79911,"corporation":false,"usgs":true,"family":"Bullen","given":"T.D.","email":"","affiliations":[],"preferred":false,"id":433867,"contributorType":{"id":1,"text":"Authors"},"rank":7},{"text":"Zuppi, G.M.","contributorId":66079,"corporation":false,"usgs":true,"family":"Zuppi","given":"G.M.","email":"","affiliations":[],"preferred":false,"id":433865,"contributorType":{"id":1,"text":"Authors"},"rank":8}]}} ]}