This research compared raw filtered waters (RFWs), XAD resin isolates (XAD-8 and XAD-4), and reverse osmosis (RO) isolates of several surface water samples from McDonalds Branch, a small freshwater fen in the New Jersey Pine Barrens (USA). RO and XAD-8 are two of the most common techniques used to isolate natural organic matter (NOM) for studies of composition and reactivity; therefore, it is important to understand how the isolates differ from bulk (unisolated) samples and from one another. Although, any comparison between the isolation methods needs to consider that XAD-8 is specifically designed to isolate the humic fraction, whereas RO concentrates a broad range of organic matter and is not specific to humics. The comparison included for all samples: weight average molecular weight (Mw), number average molecular weight (Mn), polydispersity (ρ), absorbance at 280 nm normalized to moles C (ε280) (RFW and isolates); and for isolates only: elemental analysis, % carbon distribution by 13C NMR, and aqueous FTIR spectra. As expected, RO isolation gave higher yield of NOM than XAD-8, but also higher ash content, especially Si and S. Mwdecreased in the order: RO>XAD-8>RFW>XAD-4. The Mw differences of isolates compared with RFW may be due to selective isolation (fractionation), or possibly in the case of RO to condensation or coagulation during isolation. 13C NMR results were roughly similar for the two methods, but the XAD-8 isolate was slightly higher in ‘aromatic’ C and the RO isolate was slightly higher in heteroaliphatic and carbonyl C. Infrared spectra indicated a higher carboxyl content for the XAD-8 isolates and a higher ester:carboxyl ratio for the RO isolates. The spectroscopic data thus are consistent with selective isolation of more hydrophobic compounds by XAD-8, and also with potential ester hydrolysis during that process, although further study is needed to determine whether ester hydrolysis does indeed occur. Researchers choosing between XAD and RO isolation methods for NOM need to consider first the purpose of the isolation; i.e., whether humic fractionation is desirable. Beyond that, they should consider the C yield and ash content, as well as the potential for alteration of NOM by ester hydrolysis (XAD) or condensation/coagulation (RO). Furthermore, the RO and XAD methods produce different fractions or isolates so that researchers should be careful when comparing the compositions and reactivities of NOM samples isolated by these two different techniques.
Stereogrammetric measurement of the shape of Eros using images obtained by NEAR's Multispectral Imager provides a survey of the major topographic features and slope processes on this asteroid. This curved asteroid has radii ranging from 3.1 to 17.7 km and a volume of 2535±20 km3. The center of figure is within 52 m of the center of mass provided by the Navigation team; this minimal difference suggests that there are only modest variations in density or porosity within the asteroid. Three large depressions 10, 8, and 5.3 km across represent different stages of degradation of large impact craters. Slopes on horizontal scales of ∼300 m are nearly all less than 35°, although locally scarps are much steeper. The area distribution of slopes is similar to those on Ida, Phobos, and Deimos. Regions that have slopes greater than 25° have distinct brighter markings and have fewer large ejecta blocks than do flatter areas. The albedo patterns that suggest downslope transport of regolith have sharper boundaries than those on Phobos, Deimos, and Gaspra. The morphology of the albedo patterns, their lack of discrete sources, and their concentration on steeper slopes suggest transport mechanisms different from those on the previously well-observed small bodies, perhaps due to a reduced relative effectiveness of impact gardening on Eros. Regolith is also transported in talus cones and in connected, sinuous paths extending as much as 2 km, with some evident as relatively darker material. Talus material in at least one area is a discrete superposed unit, a feature not resolved on other small bodies. Flat-floored craters that apparently contain ponded material also suggest discrete units that are not well mixed by impacts.
","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Icarus","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"Elsevier","doi":"10.1006/icar.2001.6755","issn":"00191035","usgsCitation":"Thomas, P., Joseph, J., Carcich, B., Veverka, J., Clark, B., Bell, J., Byrd, A., Chomko, R., Robinson, M., Murchie, S., Prockter, L., Cheng, A., Izenberg, N., Malin, M., Chapman, C., McFadden, L., Kirk, R.L., Gaffey, M., and Lucey, P.G., 2002, Eros: Shape, topography, and slope processes: Icarus, v. 155, no. 1, p. 18-37, https://doi.org/10.1006/icar.2001.6755.","productDescription":"20 p.","startPage":"18","endPage":"37","numberOfPages":"20","costCenters":[{"id":131,"text":"Astrogeology Science Center","active":true,"usgs":true}],"links":[{"id":232999,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"otherGeospatial":"Eros","volume":"155","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a0a2fe4b0c8380cd52236","contributors":{"authors":[{"text":"Thomas, P.C.","contributorId":32690,"corporation":false,"usgs":true,"family":"Thomas","given":"P.C.","affiliations":[],"preferred":false,"id":402845,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Joseph, J.","contributorId":14555,"corporation":false,"usgs":true,"family":"Joseph","given":"J.","email":"","affiliations":[],"preferred":false,"id":402841,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Carcich, B.","contributorId":80461,"corporation":false,"usgs":true,"family":"Carcich","given":"B.","email":"","affiliations":[],"preferred":false,"id":402854,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Veverka, J.","contributorId":71689,"corporation":false,"usgs":true,"family":"Veverka","given":"J.","email":"","affiliations":[],"preferred":false,"id":402852,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Clark, B.E.","contributorId":81662,"corporation":false,"usgs":true,"family":"Clark","given":"B.E.","email":"","affiliations":[],"preferred":false,"id":402855,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Bell, J.F. III","contributorId":97612,"corporation":false,"usgs":true,"family":"Bell","given":"J.F.","suffix":"III","email":"","affiliations":[],"preferred":false,"id":402857,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Byrd, A.W.","contributorId":104254,"corporation":false,"usgs":true,"family":"Byrd","given":"A.W.","email":"","affiliations":[],"preferred":false,"id":402858,"contributorType":{"id":1,"text":"Authors"},"rank":7},{"text":"Chomko, R.","contributorId":52755,"corporation":false,"usgs":true,"family":"Chomko","given":"R.","email":"","affiliations":[],"preferred":false,"id":402848,"contributorType":{"id":1,"text":"Authors"},"rank":8},{"text":"Robinson, M.","contributorId":50272,"corporation":false,"usgs":true,"family":"Robinson","given":"M.","affiliations":[],"preferred":false,"id":402847,"contributorType":{"id":1,"text":"Authors"},"rank":9},{"text":"Murchie, S.","contributorId":16584,"corporation":false,"usgs":true,"family":"Murchie","given":"S.","email":"","affiliations":[],"preferred":false,"id":402842,"contributorType":{"id":1,"text":"Authors"},"rank":10},{"text":"Prockter, L.","contributorId":22118,"corporation":false,"usgs":true,"family":"Prockter","given":"L.","email":"","affiliations":[],"preferred":false,"id":402844,"contributorType":{"id":1,"text":"Authors"},"rank":11},{"text":"Cheng, A.","contributorId":84950,"corporation":false,"usgs":true,"family":"Cheng","given":"A.","email":"","affiliations":[],"preferred":false,"id":402856,"contributorType":{"id":1,"text":"Authors"},"rank":12},{"text":"Izenberg, N.","contributorId":56777,"corporation":false,"usgs":true,"family":"Izenberg","given":"N.","affiliations":[],"preferred":false,"id":402850,"contributorType":{"id":1,"text":"Authors"},"rank":13},{"text":"Malin, M.","contributorId":8636,"corporation":false,"usgs":true,"family":"Malin","given":"M.","affiliations":[],"preferred":false,"id":402840,"contributorType":{"id":1,"text":"Authors"},"rank":14},{"text":"Chapman, C.","contributorId":16951,"corporation":false,"usgs":true,"family":"Chapman","given":"C.","affiliations":[],"preferred":false,"id":402843,"contributorType":{"id":1,"text":"Authors"},"rank":15},{"text":"McFadden, L.A.","contributorId":35511,"corporation":false,"usgs":true,"family":"McFadden","given":"L.A.","email":"","affiliations":[],"preferred":false,"id":402846,"contributorType":{"id":1,"text":"Authors"},"rank":16},{"text":"Kirk, Randolph L. 0000-0003-0842-9226 rkirk@usgs.gov","orcid":"https://orcid.org/0000-0003-0842-9226","contributorId":2765,"corporation":false,"usgs":true,"family":"Kirk","given":"Randolph","email":"rkirk@usgs.gov","middleInitial":"L.","affiliations":[{"id":131,"text":"Astrogeology Science Center","active":true,"usgs":true}],"preferred":true,"id":402851,"contributorType":{"id":1,"text":"Authors"},"rank":17},{"text":"Gaffey, M.","contributorId":55610,"corporation":false,"usgs":true,"family":"Gaffey","given":"M.","affiliations":[],"preferred":false,"id":402849,"contributorType":{"id":1,"text":"Authors"},"rank":18},{"text":"Lucey, P. G.","contributorId":72532,"corporation":false,"usgs":false,"family":"Lucey","given":"P.","email":"","middleInitial":"G.","affiliations":[],"preferred":false,"id":402853,"contributorType":{"id":1,"text":"Authors"},"rank":19}]}} ,{"id":70024946,"text":"70024946 - 2002 - Simulation of the mobility of metal-EDTA complexes in groundwater: The influence of contaminant metals","interactions":[],"lastModifiedDate":"2018-11-26T09:27:30","indexId":"70024946","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1565,"text":"Environmental Science & Technology","onlineIssn":"1520-5851","printIssn":"0013-936X","active":true,"publicationSubtype":{"id":10}},"title":"Simulation of the mobility of metal-EDTA complexes in groundwater: The influence of contaminant metals","docAbstract":"Reactive transport simulations were conducted to model chemical reactions between metal−EDTA (ethylenediaminetetraacetic acid) complexes during transport in a mildly acidic quartz−sand aquifer. Simulations were compared with the results of small-scale tracer tests wherein nickel−, zinc−, and calcium−EDTA complexes and free EDTA were injected into three distinct chemical zones of a plume of sewage-contaminated groundwater. One zone had a large mass of adsorbed, sewage-derived zinc; one zone had a large mass of adsorbed manganese resulting from mildly reducing conditions created by the sewage plume; and one zone had significantly less adsorbed manganese and negligible zinc background. The chemical model assumed that the dissolution of iron(III) from metal−hydroxypolymer coatings on the aquifer sediments by the metal−EDTA complexes was kinetically restricted. All other reactions, including metal−EDTA complexation, zinc and manganese adsorption, and aluminum hydroxide dissolution were assumed to reach equilibrium on the time scale of transport; equilibrium constants were either taken from the literature or determined independently in the laboratory. A single iron(III) dissolution rate constant was used to fit the breakthrough curves observed in the zone with negligible zinc background. Simulation results agreed well with the experimental data in all three zones, which included temporal moments derived from breakthrough curves at different distances downgradient from the injections and spatial moments calculated from synoptic samplings conducted at different times. Results show that the tracer cloud was near equilibrium with respect to Fe in the sediment after 11 m of transport in the Zn-contaminated region but remained far from equilibrium in the other two zones. Sensitivity studies showed that the relative rate of iron(III) dissolution by the different metal−EDTA complexes was less important than the fact that these reactions are rate controlled. Results suggest that the published solubility for ferrihydrite reasonably approximates the Fe solubility of the hydroxypolymer coatings on the sediments. Aluminum may be somewhat more soluble than represented by the equilibrium constant for gibbsite, and its dissolution may be rate controlled when reacting with Ca−EDTA complexes.
Amphibian populations are often imbedded in agricultural landscapes. Therefore the potential for contamination of their habitat is considerable. Our study examined the effects of an insecticide (carbaryl, a neurotoxin), on larval amphibian communities experiencing natural stresses of competition for resources, predation, and pond drying. In a set of experimental ponds, tadpoles of three anuran species (southern leopard frog [Rana sphenocephala], plains leopard frog [R. blairi], and the Woodhouse's toad [Bufo woodhousii]) were added to 1000-L ponds containing leaf litter, plankton, two newts (Notophthalmus viridescens), and four overwintered green frog (R. clamitans) tadpoles. We manipulated the overall tadpole density (low or high), pond hydroperiod (constant or drying), and chemical exposure (0, 3.5, 5.0, or 7.0 mg/L carbaryl) of the ponds. We measured mass, time, and survival to metamorphosis to determine treatment effects. Carbaryl positively affected Woodhouse's toad survival, although it had a negligible effect on both leopard frog species. Tadpole density interacted with the chemical treatment: Proportionately more Woodhouse's toads survived to metamorphosis in high-density environments than in low-density or control environments. Greater survival may be an indirect effect of increased algal food resources from carbaryl exposure. Most newts lost mass over the course of the experiment, although ponds with drying hydroperiods and high anuran density were the least favorable environments. Overwintered green frogs exposed to carbaryl had longer larval periods on average than did green frogs in control ponds. Our study demonstrated that even sublethal, short-lived contaminants can alter natural communities in ways that cannot be predicted from simple, one-factor studies.
","language":"English","publisher":"Wiley","doi":"10.2307/3061155","usgsCitation":"Boone, M., and Semlitsch, R.D., 2002, Interactions of an insecticide with competition and pond drying in amphibian communities: Ecological Applications, v. 12, no. 1, p. 307-316, https://doi.org/10.2307/3061155.","productDescription":"10 p.","startPage":"307","endPage":"316","costCenters":[],"links":[{"id":236243,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Missouri","county":"Boone County","city":"Columbia","otherGeospatial":"University of Missouri-Columbia Research Park","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -92.34832763671875,\n 38.93003656944158\n ],\n [\n -92.32086181640625,\n 38.93003656944158\n ],\n [\n -92.32086181640625,\n 38.94285503599089\n ],\n [\n -92.34832763671875,\n 38.94285503599089\n ],\n [\n -92.34832763671875,\n 38.93003656944158\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"12","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a3cc9e4b0c8380cd63040","contributors":{"authors":[{"text":"Boone, M.D.","contributorId":31157,"corporation":false,"usgs":true,"family":"Boone","given":"M.D.","email":"","affiliations":[],"preferred":false,"id":403680,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Semlitsch, R. D.","contributorId":22522,"corporation":false,"usgs":true,"family":"Semlitsch","given":"R.","email":"","middleInitial":"D.","affiliations":[],"preferred":false,"id":403679,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70025075,"text":"70025075 - 2002 - Environmental contaminants in prey and tissues of the peregrine falcon in the Big Bend Region, Texas, USA.","interactions":[],"lastModifiedDate":"2022-01-07T15:40:31.395016","indexId":"70025075","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1555,"text":"Environmental Pollution","active":true,"publicationSubtype":{"id":10}},"title":"Environmental contaminants in prey and tissues of the peregrine falcon in the Big Bend Region, Texas, USA.","docAbstract":"Peregrine falcons (Falco peregrinus) have been recorded nesting in Big Bend National Park, Texas, USA and other areas of the Chihuahuan Desert since the early 1900s. From 1993 to 1996, peregrine falcon productivity rates were very low and coincided with periods of low rainfall. However, low productivity also was suspected to be caused by environmental contaminants. To evaluate potential impacts of contaminants on peregrine falcon populations, likely avian and bat prey species were collected during 1994 and 1997 breeding seasons in selected regions of western Texas, primarily in Big Bend National Park. Tissues of three peregrine falcons found injured or dead and feathers of one live fledgling also were analyzed. Overall, mean concentrations of DDE [1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene], a metabolite of DDT [1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane], were low in all prey species except for northern rough-winged swallows (Stelgidopteryx serripennis, mean = 5.1 microg/g ww). Concentrations of mercury and selenium were elevated in some species, up to 2.5 microg/g dw, and 15 microg/g dw, respectively, which upon consumption could seriously affect reproduction of top predators. DDE levels near 5 microg/g ww were detected in carcass of one peregrine falcon found dead but the cause of death was unknown. Mercury, selenium, and DDE to some extent, may be contributing to low reproductive rates of peregrine falcons in the Big Bend region.
","language":"English","publisher":"ScienceDirect","doi":"10.1016/S0269-7491(01)00207-X","usgsCitation":"Mora, M., Skiles, R., McKinney, B., Paredes, M., Buckler, D., Papoulias, D., and Klein, D., 2002, Environmental contaminants in prey and tissues of the peregrine falcon in the Big Bend Region, Texas, USA.: Environmental Pollution, v. 116, no. 1, p. 169-176, https://doi.org/10.1016/S0269-7491(01)00207-X.","productDescription":"8 p.","startPage":"169","endPage":"176","costCenters":[{"id":192,"text":"Columbia Environmental Research Center","active":true,"usgs":true}],"links":[{"id":235763,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Texas","otherGeospatial":"Big Bend National Park","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -103.6505126953125,\n 28.950475674848008\n ],\n [\n -102.8045654296875,\n 28.950475674848008\n ],\n [\n -102.8045654296875,\n 29.597341920567366\n ],\n [\n -103.6505126953125,\n 29.597341920567366\n ],\n [\n -103.6505126953125,\n 28.950475674848008\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"116","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a09b2e4b0c8380cd52012","contributors":{"authors":[{"text":"Mora, M.","contributorId":51513,"corporation":false,"usgs":true,"family":"Mora","given":"M.","email":"","affiliations":[],"preferred":false,"id":403715,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Skiles, R.","contributorId":51075,"corporation":false,"usgs":true,"family":"Skiles","given":"R.","email":"","affiliations":[],"preferred":false,"id":403714,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"McKinney, B.","contributorId":57639,"corporation":false,"usgs":true,"family":"McKinney","given":"B.","affiliations":[],"preferred":false,"id":403716,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Paredes, M.","contributorId":33503,"corporation":false,"usgs":true,"family":"Paredes","given":"M.","email":"","affiliations":[],"preferred":false,"id":403710,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Buckler, D.","contributorId":33900,"corporation":false,"usgs":true,"family":"Buckler","given":"D.","email":"","affiliations":[],"preferred":false,"id":403712,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Papoulias, D. 0000-0002-5106-2469","orcid":"https://orcid.org/0000-0002-5106-2469","contributorId":33886,"corporation":false,"usgs":true,"family":"Papoulias","given":"D.","affiliations":[],"preferred":false,"id":403711,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Klein, D.","contributorId":36933,"corporation":false,"usgs":true,"family":"Klein","given":"D.","affiliations":[],"preferred":false,"id":403713,"contributorType":{"id":1,"text":"Authors"},"rank":7}]}} ,{"id":1004125,"text":"1004125 - 2002 - Spent shot availability and ingestion on areas managed for mourning doves","interactions":[],"lastModifiedDate":"2017-02-22T14:44:41","indexId":"1004125","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3779,"text":"Wildlife Society Bulletin","onlineIssn":"1938-5463","printIssn":"0091-7648","active":true,"publicationSubtype":{"id":10}},"title":"Spent shot availability and ingestion on areas managed for mourning doves","docAbstract":"Mourning dove (Zenaida macroura) hunting is becoming increasingly popular, especially in managed shooting fields. Given the possible increase in the availability of lead (Pb) shot on these areas, our objective was to estimate availability and ingestion of spent shot at the Eagle Bluffs Conservation Area (EBCA, hunted with nontoxic shot) and the James A. Reed Memorial Wildlife Area (JARWA, hunted with Pb shot) in Missouri. During 1998, we collected soil samples one or 2 weeks prior to the hunting season (prehunt) and after 4 days of dove hunting (posthunt). We also collected information on number of doves harvested, number of shots fired, shotgun gauge, and shotshell size used. Dove carcasses were collected on both areas during 1998-99. At EBCA, 60 hunters deposited an estimated 64,775 pellets/ha of nontoxic shot on or around the managed field. At JARWA, approximately 1,086,275 pellets/ha of Pb shot were deposited by 728 hunters. Our posthunt estimates of spent-shot availability from soil sampling were 0 pellets/ha for EBCA and 6,342 pellets/ha for JARWA. Our findings suggest that existing soil sampling protocols may not provide accurate estimates of spent-shot availability in managed dove shooting fields. During 1998-99, 15 of 310 (4.8%) mourning doves collected from EBCA had ingested nontoxic shot. Of those doves, 6 (40.0%) contained a?Y7 shot pellets. In comparison, only 2 of 574 (0.3%) doves collected from JARWA had ingested Pb shot. Because a greater proportion of doves ingested multiple steel pellets compared to Pb pellets, we suggest that doves feeding in fields hunted with Pb shot may succumb to acute Pb toxicosis and thus become unavailable to harvest, resulting in an underestimate of ingestion rates. Although further research is needed to test this hypothesis, our findings may partially explain why previous studies have shown few doves with ingested Pb shot despite their feeding on areas with high Pb shot availability.
","language":"English","publisher":"U.S. Fish and Wildlife Service","usgsCitation":"Schulz, J., Millspaugh, J., Washburn, B., Wester, G., Lanigan, J., and Franson, J.C., 2002, Spent shot availability and ingestion on areas managed for mourning doves: Wildlife Society Bulletin, v. 30, no. 1, p. 112-120.","productDescription":"p. 112-120","startPage":"112","endPage":"120","numberOfPages":"9","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":456,"text":"National Wildlife Health Center","active":true,"usgs":true}],"links":[{"id":135783,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Missouri","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -92.3891830444336,\n 38.81817742577599\n ],\n [\n -92.38815307617188,\n 38.825399456730835\n ],\n [\n -92.39433288574219,\n 38.84652637703232\n ],\n [\n -92.42712020874023,\n 38.880075866440414\n ],\n [\n -92.44068145751953,\n 38.89236892551996\n ],\n [\n -92.45904922485352,\n 38.90212168702489\n ],\n [\n -92.46883392333984,\n 38.905995699991145\n ],\n [\n -92.47552871704102,\n 38.90319040137062\n ],\n [\n -92.47604370117186,\n 38.89824746267324\n ],\n [\n -92.47758865356445,\n 38.88889501576177\n ],\n [\n -92.47861862182617,\n 38.88395108203398\n ],\n [\n -92.47861862182617,\n 38.87660135553313\n ],\n [\n -92.47638702392577,\n 38.87392853923629\n ],\n [\n -92.46831893920898,\n 38.86898356409656\n ],\n [\n -92.44943618774414,\n 38.847061154375304\n ],\n [\n -92.44583129882812,\n 38.8378356818057\n ],\n [\n -92.43038177490234,\n 38.825265722073624\n ],\n [\n -92.41579055786133,\n 38.81844492146606\n ],\n [\n -92.40257263183594,\n 38.818578668934315\n ],\n [\n -92.39656448364258,\n 38.818979909831924\n ],\n [\n -92.3891830444336,\n 38.81817742577599\n ]\n ]\n ]\n }\n },\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -94.34062957763672,\n 38.8956422619276\n ],\n [\n -94.31934356689453,\n 38.895107849961725\n ],\n [\n -94.31900024414062,\n 38.896711073795146\n ],\n [\n -94.31582450866699,\n 38.896711073795146\n ],\n [\n -94.31565284729004,\n 38.895107849961725\n ],\n [\n -94.31024551391602,\n 38.89437302694244\n ],\n [\n -94.31058883666992,\n 38.89023115500578\n ],\n [\n -94.31170463562012,\n 38.89003073572137\n ],\n [\n -94.31299209594727,\n 38.872859384572244\n ],\n [\n -94.30389404296875,\n 38.87265891628226\n ],\n [\n -94.30432319641113,\n 38.86403824494496\n ],\n [\n -94.30569648742674,\n 38.863837751777666\n ],\n [\n -94.30569648742674,\n 38.862434283776295\n ],\n [\n -94.3044090270996,\n 38.86223378608605\n ],\n [\n -94.3044090270996,\n 38.86109762182888\n ],\n [\n -94.30432319641113,\n 38.86036244704732\n ],\n [\n -94.30638313293456,\n 38.86042928143247\n ],\n [\n -94.30672645568846,\n 38.8547481344397\n ],\n [\n -94.30415153503418,\n 38.8547481344397\n ],\n [\n -94.30458068847656,\n 38.85187396956363\n ],\n [\n -94.30870056152342,\n 38.85187396956363\n ],\n [\n -94.3092155456543,\n 38.850002357905105\n ],\n [\n -94.32929992675781,\n 38.85053710911831\n ],\n [\n -94.32904243469238,\n 38.85768902013159\n ],\n [\n -94.33719635009766,\n 38.857755857029396\n ],\n [\n -94.33745384216309,\n 38.85120554248162\n ],\n [\n -94.33917045593262,\n 38.85147291406818\n ],\n [\n -94.34380531311035,\n 38.855617045142374\n ],\n [\n -94.34371948242188,\n 38.85849105875954\n ],\n [\n -94.34062957763672,\n 38.8956422619276\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"30","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e49e2e4b07f02db5e4b61","contributors":{"authors":[{"text":"Schulz, J.H.","contributorId":67856,"corporation":false,"usgs":true,"family":"Schulz","given":"J.H.","email":"","affiliations":[],"preferred":false,"id":315222,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Millspaugh, J.J.","contributorId":99105,"corporation":false,"usgs":true,"family":"Millspaugh","given":"J.J.","email":"","affiliations":[],"preferred":false,"id":315224,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Washburn, B.E.","contributorId":99953,"corporation":false,"usgs":true,"family":"Washburn","given":"B.E.","affiliations":[],"preferred":false,"id":315225,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Wester, G.R.","contributorId":57044,"corporation":false,"usgs":true,"family":"Wester","given":"G.R.","email":"","affiliations":[],"preferred":false,"id":315221,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Lanigan, J. T. III","contributorId":12831,"corporation":false,"usgs":true,"family":"Lanigan","given":"J. T.","suffix":"III","affiliations":[],"preferred":false,"id":315220,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Franson, J. C. 0000-0002-0251-4238","orcid":"https://orcid.org/0000-0002-0251-4238","contributorId":99071,"corporation":false,"usgs":true,"family":"Franson","given":"J.","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":315223,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}} ,{"id":70025122,"text":"70025122 - 2002 - Solving Wakulla Springs underwater mysteries. Using GPS to map Florida's underground caverns","interactions":[],"lastModifiedDate":"2012-03-12T17:20:27","indexId":"70025122","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1918,"text":"Hydro International","active":true,"publicationSubtype":{"id":10}},"title":"Solving Wakulla Springs underwater mysteries. Using GPS to map Florida's underground caverns","docAbstract":"Located in the Woodville Karst Plain stretching south from Tallahassee to the Gulf of Mexico, Florida's Wakulla Springs is one of the largest and deepest freshwater Springs in the world. It is also a gateway into one of the longest underwater cave system in the United States, a system that remained largely unexplored until recently. Soon, however, thanks to one of the world's most extreme scientific and exploration-related diving projects ever undertaken, visitors to Wakulla Springs State Park will be able to take a virtual tour through the Spring's huge underwater labyrinth. Using such cutting-edge technology as a 3D Digital Wall Mapper (DWM) and the Global Positioning System (GPS), the Wakulla 2 Expedition - with 151 volunteer cave divers, scientists and engineers from all over the world - created the world's first three-dimensional digital map of an underwater cave. Underwater caves are priceless treasures, helping supply fresh water to the region as well as acting as 'time capsules' to the past. Home to creatures found in few other places, areas such as Wakulla face threats of pollution and over-development. Wakulla 2 hopes their 3D interactive 'swim through' will help increase the understanding and preservation of these important areas.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Hydro International","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","issn":"13854569","usgsCitation":"Am, E.B., 2002, Solving Wakulla Springs underwater mysteries. Using GPS to map Florida's underground caverns: Hydro International, v. 6, no. 6, p. 56-59.","startPage":"56","endPage":"59","numberOfPages":"4","costCenters":[],"links":[{"id":235838,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"6","issue":"6","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b925fe4b08c986b319e9c","contributors":{"authors":[{"text":"Am, Ende B.","contributorId":6643,"corporation":false,"usgs":true,"family":"Am","given":"Ende","email":"","middleInitial":"B.","affiliations":[],"preferred":false,"id":403899,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70024137,"text":"70024137 - 2002 - Performance of a satellite-linked GPS on Pacific walruses (Odobenus rosmarus divergens)","interactions":[],"lastModifiedDate":"2022-08-15T16:49:23.459427","indexId":"70024137","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3093,"text":"Polar Biology","active":true,"publicationSubtype":{"id":10}},"displayTitle":"Performance of a satellite-linked GPS on Pacific walruses (Odobenus rosmarus divergens)","title":"Performance of a satellite-linked GPS on Pacific walruses (Odobenus rosmarus divergens)","docAbstract":"We evaluated the utility of a satellite-linked GPS in obtaining location data from Pacific walruses (Odobenus rosmarus divergens). A unit was attached to one of the tusks of each of three adult male walruses in Bristol Bay, Alaska. The units were designed to relay GPS positions through the Argos Data Collection and Location System. The GPS was only minimally effective in obtaining location data. An average of only 5% of the attempts yielded a position, and only a small number of these were locations at sea. The paucity of successful attempts was probably due to infrequent and brief surfacings of the GPS, the proximity of cliffs to predominant haul-out sites in the study region, and the packing of animals when they were hauled out in herds. Argos was effective in relaying GPS positions in this study, but as GPS technology advances, and its application to marine mammal studies becomes more prevalent, it seems that the greatest challenge to the study of many species will be in data retrieval.
","language":"English","publisher":"Springer Link","doi":"10.1007/s00300-001-0338-7","usgsCitation":"Jay, C.V., and Garner, G.W., 2002, Performance of a satellite-linked GPS on Pacific walruses (Odobenus rosmarus divergens): Polar Biology, v. 25, no. 3, p. 235-237, https://doi.org/10.1007/s00300-001-0338-7.","productDescription":"3 p.","startPage":"235","endPage":"237","numberOfPages":"3","costCenters":[{"id":114,"text":"Alaska Science Center","active":true,"usgs":true}],"links":[{"id":231874,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"25","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a7686e4b0c8380cd7816d","contributors":{"authors":[{"text":"Jay, Chadwick V. 0000-0002-9559-2189 cjay@usgs.gov","orcid":"https://orcid.org/0000-0002-9559-2189","contributorId":192736,"corporation":false,"usgs":true,"family":"Jay","given":"Chadwick","email":"cjay@usgs.gov","middleInitial":"V.","affiliations":[{"id":116,"text":"Alaska Science Center Biology MFEB","active":true,"usgs":true}],"preferred":true,"id":400150,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Garner, Gerald W.","contributorId":149918,"corporation":false,"usgs":false,"family":"Garner","given":"Gerald","email":"","middleInitial":"W.","affiliations":[{"id":13117,"text":"Institute of Arctic Biology, University of Alaska Fairbanks","active":true,"usgs":false}],"preferred":false,"id":400151,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70024099,"text":"70024099 - 2002 - Biot-Gassmann theory for velocities of gas hydrate-bearing sediments","interactions":[],"lastModifiedDate":"2022-01-19T16:56:05.196058","indexId":"70024099","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1808,"text":"Geophysics","active":true,"publicationSubtype":{"id":10}},"title":"Biot-Gassmann theory for velocities of gas hydrate-bearing sediments","docAbstract":"Elevated elastic velocities are a distinct physical property of gas hydrate-bearing sediments. A number of velocity models and equations (e.g., pore-filling model, cementation model, effective medium theories, weighted equations, and time-average equations) have been used to describe this effect. In particular, the weighted equation and effective medium theory predict reasonably well the elastic properties of unconsolidated gas hydrate-bearing sediments. A weakness of the weighted equation is its use of the empirical relationship of the time-average equation as one element of the equation. One drawback of the effective medium theory is its prediction of unreasonably higher shear-wave velocity at high porosities, so that the predicted velocity ratio does not agree well with the observed velocity ratio. To overcome these weaknesses, a method is proposed, based on Biot-Gassmann theories and assuming the formation velocity ratio (shear to compressional velocity) of an unconsolidated sediment is related to the velocity ratio of the matrix material of the formation and its porosity. Using the Biot coefficient calculated from either the weighted equation or from the effective medium theory, the proposed method accurately predicts the elastic properties of unconsolidated sediments with or without gas hydrate concentration. This method was applied to the observed velocities at the Mallik 2L-39 well, Mackenzie Delta, Canada.","language":"English","publisher":"GeoScienceWorld","doi":"10.1190/1.1527072","usgsCitation":"Lee, M.W., 2002, Biot-Gassmann theory for velocities of gas hydrate-bearing sediments: Geophysics, v. 67, no. 6, p. 1711-1719, https://doi.org/10.1190/1.1527072.","productDescription":"9 p.","startPage":"1711","endPage":"1719","costCenters":[],"links":[{"id":231907,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"Canada","otherGeospatial":"Mackenzie Delta","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -138.076171875,\n 67.89208614070753\n ],\n [\n -129.90234375,\n 67.89208614070753\n ],\n [\n -129.90234375,\n 69.71810669906763\n ],\n [\n -138.076171875,\n 69.71810669906763\n ],\n [\n -138.076171875,\n 67.89208614070753\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"67","issue":"6","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059f19ee4b0c8380cd4ad3d","contributors":{"authors":[{"text":"Lee, Myung W.","contributorId":84358,"corporation":false,"usgs":true,"family":"Lee","given":"Myung","middleInitial":"W.","affiliations":[],"preferred":false,"id":400021,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70024476,"text":"70024476 - 2002 - Does bird community structure vary with landscape patchiness? A Chihuahuan Desert perspective","interactions":[],"lastModifiedDate":"2012-03-12T17:20:09","indexId":"70024476","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2939,"text":"Oikos","active":true,"publicationSubtype":{"id":10}},"title":"Does bird community structure vary with landscape patchiness? A Chihuahuan Desert perspective","docAbstract":"During the springs of 1995-1997, we studied birds and landscapes at 70 sites in the Chihuahuan Desert to assess relations between bird community structure and landscape patchiness. Within each of two spatial extents (1-kin and 2-km-radius areas centered on each site), we measured the number of patches of individual land-cover types and the total number of patches of all land-cover types. Mean bird richness, and the mean abundance and probability of occurrence of most bird species were significantly correlated with one or more of these variables. Contrary to evidence from other systems, positive association with landscape patchiness did not increase with the degree to which species were habitat generalists, was not negatively related to body size, and did not differ between neotropical migrants and nonmigrants. For the communities' primary constituent species as a group, the strength of positive and negative associations with patchiness did not differ between landscape extents. Within the 1-km but not the 2-km extent, habitat specialists were more positively and negatively associated with patchiness than were habitat generalists. In general, however, neither habitat breadth, body size, nor migratory status seemed to be responsible for associations with landscape patchiness. Mean richness, and the mean abundance and probability of occurrence of most species were significantly correlated with patchiness within one or both extents, and patchiness of all of the most extensive land-cover types was influential. The simplest explanation for most of the bird-patchiness relations we found is that the associations reflected species-specific habitat needs. Through effects on avian richness, abundance, and occurrence, landscape patchiness affected bird community structure. A more complete understanding of the effects of landscape patchiness on bird community structure is likely to emerge when ecologists study the patchiness of major land-cover types at various spatial extents.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Oikos","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1034/j.1600-0706.2002.980210.x","issn":"00301299","usgsCitation":"Gutzwiller, K., and Barrow, W., 2002, Does bird community structure vary with landscape patchiness? A Chihuahuan Desert perspective: Oikos, v. 98, no. 2, p. 284-298, https://doi.org/10.1034/j.1600-0706.2002.980210.x.","startPage":"284","endPage":"298","numberOfPages":"15","costCenters":[],"links":[{"id":207941,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1034/j.1600-0706.2002.980210.x"},{"id":233262,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"98","issue":"2","noUsgsAuthors":false,"publicationDate":"2002-08-29","publicationStatus":"PW","scienceBaseUri":"505a038ce4b0c8380cd50521","contributors":{"authors":[{"text":"Gutzwiller, K.J.","contributorId":78124,"corporation":false,"usgs":true,"family":"Gutzwiller","given":"K.J.","affiliations":[],"preferred":false,"id":401414,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Barrow, W.C. Jr. 0000-0003-4671-2823","orcid":"https://orcid.org/0000-0003-4671-2823","contributorId":11183,"corporation":false,"usgs":true,"family":"Barrow","given":"W.C.","suffix":"Jr.","affiliations":[],"preferred":false,"id":401413,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70024512,"text":"70024512 - 2002 - Low abundance materials at the mars pathfinder landing site: An investigation using spectral mixture analysis and related techniques","interactions":[],"lastModifiedDate":"2012-03-12T17:20:04","indexId":"70024512","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1963,"text":"Icarus","active":true,"publicationSubtype":{"id":10}},"title":"Low abundance materials at the mars pathfinder landing site: An investigation using spectral mixture analysis and related techniques","docAbstract":"Recalibrated and geometrically registered multispectral images from the Imager for Mars Pathfinder (IMP) were analyzed using Spectral Mixture Analysis (SMA) and related techniques. SMA models a multispectral image scene as a linear combination of end-member spectra, and anomalous materials which do not fit the model are detected as model residuals. While most of the IMP data studied here are modeled generally well using \"Bright Dust,\" \"Gray Rock,\" and \"Shade\" image endmembers, additional anomalous materials were detected through careful analysis of root mean square (RMS) error images resulting from SMA. For example, analysis of SMA fraction and RMS images indicates spectral differences within a previously monolithologic Dark Soil class. A type of Dark Soil that has high fractional abundances in rock fraction images (Gray Rock Soil) was identified. Other anomalous materials identified included a previously noted \"Black Rock\" lithology, a class of possibly indurated, compacted, or partially cemented soils (\"Intermediate Soil\"), and a unit referred to as \"Anomalous Patches\" on at least one rock. The Black Rock lithology has a strong 900-1000-nm absorption, and modeling of the derived image endmembers using a laboratory reference endmember modeling (REM) approach produced best-fit model spectra that are most consistent with the presence of high-Ca pyroxenes and/or olivine, crystalline ferric oxide minerals, or mixtures of these materials as important components of the Black Rock endmember. More unique mineralogic identifications could not be obtained using our initial REM analyses. Both Intermediate Soil and Anomalous Patches units exhibit a relatively narrow 860-950-nm absorption that is consistent with the presence of either low-Ca pyroxenes or a cementing crystalline ferric oxide mineral. ?? 2002 Elsevier Science (USA).","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Icarus","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1006/icar.2002.6865","issn":"00191035","usgsCitation":"Bell, J., Farrand, W.H., Johnson, J.R., and Morris, R., 2002, Low abundance materials at the mars pathfinder landing site: An investigation using spectral mixture analysis and related techniques: Icarus, v. 158, no. 1, p. 56-71, https://doi.org/10.1006/icar.2002.6865.","startPage":"56","endPage":"71","numberOfPages":"16","costCenters":[],"links":[{"id":207973,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1006/icar.2002.6865"},{"id":233303,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"158","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a4a00e4b0c8380cd68a4f","contributors":{"authors":[{"text":"Bell, J.F. III","contributorId":97612,"corporation":false,"usgs":true,"family":"Bell","given":"J.F.","suffix":"III","email":"","affiliations":[],"preferred":false,"id":401533,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Farrand, W. H.","contributorId":64372,"corporation":false,"usgs":true,"family":"Farrand","given":"W.","email":"","middleInitial":"H.","affiliations":[],"preferred":false,"id":401531,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Johnson, J. R.","contributorId":69278,"corporation":false,"usgs":true,"family":"Johnson","given":"J.","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":401532,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Morris, R.V.","contributorId":6978,"corporation":false,"usgs":true,"family":"Morris","given":"R.V.","affiliations":[],"preferred":false,"id":401530,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70024556,"text":"70024556 - 2002 - Sediment transport on the Palos Verdes shelf over seasonal to decadal time scales","interactions":[],"lastModifiedDate":"2012-03-12T17:20:13","indexId":"70024556","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","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":"Sediment transport on the Palos Verdes shelf over seasonal to decadal time scales","docAbstract":"We combine direct observations, longer-term wave data, and model calculations to characterize resuspension and transport of fine-grained, effluent-affected sediment on the Palos Verdes shelf. Near-bed waves, currents, and suspended sediment concentrations were monitored during the winter of 1992-93 with a bottom tripod and current-meter mooring at a 63-m-deep site. Wave conditions that winter were moderate (??? 2 year recurrence interval), and mean current was alongshelf to the northwest; currents were not significantly correlated with wave conditions. Seven wave events during the winter (December-March) produced near-bed wave orbital velocities at the study site in excess of 14 cm s-1, the observed threshold for significant resuspension. Three of these events occurred during the bottom tripod deployment and are characterized by the highest persistent suspended sediment concentrations in the tripod record. Suspended sediment flux was alongshelf to the northwest for 5 of the 6 wave events for which current data were available; one event occurred during low southeast currents. Measured suspended sediment concentration and grain size generally agree with values that were calculated using a shelf sediment transport model with no adjustment of parameters from values determined for two muddy sites on the northern California shelf. We extend our seasonal observations to a period of almost 2 decades by applying the observed thresholds for wave-driven resuspension to near-bed wave conditions calculated from NDBC Buoy 46025 surface wave data. An average of 10 resuspension events per year, with an average duration of 1.6 days, were identified at a water depth of 60 m; the number of events dropped to 3 per year at 90 m, beyond the shelf break. For the majority of these events, calculated net suspended sediment flux is toward the northwest (alongshelf) at an average rate of 140 kg m-1 h-1; about a third of the events have net southeastward flux at an average rate of 30 kg m-1 h-1. The calculated thickness of the resuspended surface layer of the bed was less than 1 cm for all events at 60 m. ?? 2002 Elsevier Science Ltd. All rights reserved.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Continental Shelf Research","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0278-4343(01)00116-9","issn":"02784343","usgsCitation":"Wiberg, P., Drake, D., Harris, C.K., and Noble, M., 2002, Sediment transport on the Palos Verdes shelf over seasonal to decadal time scales: Continental Shelf Research, v. 22, no. 6-7, p. 987-1004, https://doi.org/10.1016/S0278-4343(01)00116-9.","startPage":"987","endPage":"1004","numberOfPages":"18","costCenters":[],"links":[{"id":207734,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0278-4343(01)00116-9"},{"id":232913,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"22","issue":"6-7","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505b89e6e4b08c986b316f22","contributors":{"authors":[{"text":"Wiberg, P.L.","contributorId":33827,"corporation":false,"usgs":true,"family":"Wiberg","given":"P.L.","email":"","affiliations":[],"preferred":false,"id":401696,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Drake, D.E.","contributorId":48150,"corporation":false,"usgs":true,"family":"Drake","given":"D.E.","email":"","affiliations":[],"preferred":false,"id":401697,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Harris, C. K.","contributorId":80337,"corporation":false,"usgs":true,"family":"Harris","given":"C.","email":"","middleInitial":"K.","affiliations":[],"preferred":false,"id":401698,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Noble, M.","contributorId":15340,"corporation":false,"usgs":true,"family":"Noble","given":"M.","email":"","affiliations":[],"preferred":false,"id":401695,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70024561,"text":"70024561 - 2002 - The proximal part of the giant submarine Wailau landslide, Molokai, Hawaii","interactions":[],"lastModifiedDate":"2012-03-12T17:20:07","indexId":"70024561","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","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":"The proximal part of the giant submarine Wailau landslide, Molokai, Hawaii","docAbstract":"The main break-in-slope on the northern submarine flank of Molokai at -1500 to -1250 m is a shoreline feature that has been only modestly modified by the Wailau landslide. Submarine canyons above the break-in-slope, including one meandering stream, were subaerially carved. Where such canyons cross the break-in-slope, plunge pools may form by erosion from bedload sediment carried down the canyons. West Molokai Volcano continued infrequent volcanic activity that formed a series of small coastal sea cliffs, now submerged, as the island subsided. Lavas exposed at the break-in-slope are subaerially erupted and emplaced tholeiitic shield lavas. Submarine rejuvenated-stage volcanic cones formed after the landslide took place and following at least 400-500 m of subsidence after the main break-in-slope had formed. The sea cliff on east Molokai is not the headwall of the landslide, nor did it form entirely by erosion. It may mark the location of a listric fault similar to the Hilina faults on present-day Kilauea Volcano. The Wailau landslide occurred about 1.5 Ma and the Kalaupapa Peninsula most likely formed 330??5 ka. Molokai is presently stable relative to sea level and has subsided no more than 30 m in the last 330 ka. At their peak, West and East Molokai stood 1.6 and 3 km above sea level. High rainfall causes high surface runoff and formation of canyons, and increases groundwater pressure that during dike intrusions may lead to flank failure. Active shield or postshield volcanism (with dikes injected along rift zones) and high rainfall appear to be two components needed to trigger the deep-seated giant Hawaiian landslides. ?? 2002 Elsevier Science B.V. All rights reserved.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Volcanology and Geothermal Research","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0377-0273(01)00261-X","issn":"03770273","usgsCitation":"Clague, D., and Moore, J., 2002, The proximal part of the giant submarine Wailau landslide, Molokai, Hawaii: Journal of Volcanology and Geothermal Research, v. 113, no. 1-2, p. 259-287, https://doi.org/10.1016/S0377-0273(01)00261-X.","startPage":"259","endPage":"287","numberOfPages":"29","costCenters":[],"links":[{"id":207778,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0377-0273(01)00261-X"},{"id":232981,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"113","issue":"1-2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505baedae4b08c986b3243b3","contributors":{"authors":[{"text":"Clague, D.A.","contributorId":36129,"corporation":false,"usgs":true,"family":"Clague","given":"D.A.","email":"","affiliations":[],"preferred":false,"id":401714,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Moore, J.G.","contributorId":67496,"corporation":false,"usgs":true,"family":"Moore","given":"J.G.","email":"","affiliations":[],"preferred":false,"id":401715,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70024602,"text":"70024602 - 2002 - Comparing shear-wave velocity profiles inverted from multichannel surface wave with borehole measurements","interactions":[],"lastModifiedDate":"2012-03-12T17:20:07","indexId":"70024602","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3418,"text":"Soil Dynamics and Earthquake Engineering","active":true,"publicationSubtype":{"id":10}},"title":"Comparing shear-wave velocity profiles inverted from multichannel surface wave with borehole measurements","docAbstract":"Recent field tests illustrate the accuracy and consistency of calculating near-surface shear (S)-wave velocities using multichannel analysis of surface waves (MASW). S-wave velocity profiles (S-wave velocity vs. depth) derived from MASW compared favorably to direct borehole measurements at sites in Kansas, British Columbia, and Wyoming. Effects of changing the total number of recording channels, sampling interval, source offset, and receiver spacing on the inverted S-wave velocity were studied at a test site in Lawrence, Kansas. On the average, the difference between MASW calculated Vs and borehole measured Vs in eight wells along the Fraser River in Vancouver, Canada was less than 15%. One of the eight wells was a blind test well with the calculated overall difference between MASW and borehole measurements less than 9%. No systematic differences were observed in derived Vs values from any of the eight test sites. Surface wave analysis performed on surface data from Wyoming provided S-wave velocities in near-surface materials. Velocity profiles from MASW were confirmed by measurements based on suspension log analysis. ?? 2002 Elsevier Science Ltd. All rights reserved.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Soil Dynamics and Earthquake Engineering","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0267-7261(02)00008-8","issn":"02677261","usgsCitation":"Xia, J., Miller, R., Park, C., Hunter, J., Harris, J.B., and Ivanov, J., 2002, Comparing shear-wave velocity profiles inverted from multichannel surface wave with borehole measurements: Soil Dynamics and Earthquake Engineering, v. 22, no. 3, p. 181-190, https://doi.org/10.1016/S0267-7261(02)00008-8.","startPage":"181","endPage":"190","numberOfPages":"10","costCenters":[],"links":[{"id":207780,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0267-7261(02)00008-8"},{"id":232983,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"22","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059f839e4b0c8380cd4cf5e","contributors":{"authors":[{"text":"Xia, J.","contributorId":63513,"corporation":false,"usgs":true,"family":"Xia","given":"J.","email":"","affiliations":[],"preferred":false,"id":401861,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Miller, R. D.","contributorId":92693,"corporation":false,"usgs":true,"family":"Miller","given":"R. D.","affiliations":[],"preferred":false,"id":401863,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Park, C.B.","contributorId":21714,"corporation":false,"usgs":true,"family":"Park","given":"C.B.","email":"","affiliations":[],"preferred":false,"id":401860,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Hunter, J. A.","contributorId":94067,"corporation":false,"usgs":true,"family":"Hunter","given":"J. A.","affiliations":[],"preferred":false,"id":401864,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Harris, J. B.","contributorId":80441,"corporation":false,"usgs":true,"family":"Harris","given":"J.","email":"","middleInitial":"B.","affiliations":[],"preferred":false,"id":401862,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Ivanov, J.","contributorId":107068,"corporation":false,"usgs":true,"family":"Ivanov","given":"J.","email":"","affiliations":[],"preferred":false,"id":401865,"contributorType":{"id":1,"text":"Authors"},"rank":6}]}} ,{"id":70024615,"text":"70024615 - 2002 - Educational background and professional participation by federal wildlife biologists: Implications for science, management, and The Wildlife Society","interactions":[],"lastModifiedDate":"2018-03-28T11:56:58","indexId":"70024615","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3779,"text":"Wildlife Society Bulletin","onlineIssn":"1938-5463","printIssn":"0091-7648","active":true,"publicationSubtype":{"id":10}},"title":"Educational background and professional participation by federal wildlife biologists: Implications for science, management, and The Wildlife Society","docAbstract":"Over 2,000 people are employed in wildlife biology in the United States federal government. The size of this constituency motivated me to examine the amount of formal education federal biologists have received and the extent of continuing education they undertake by reading journals or attending scientific meetings. Most federal biologists who are members of The Wildlife Society (TWS) have a graduate degree. However, one-third have only a Bachelor of Science degree, despite the current trend toward hiring people with graduate degrees. Most federal biologists are not research biologists. Numbers of journals subscribed to was positively related to educational level. Less than one-third of all wildlife biologists employed by the United States Fish and Wildlife Service are members of TWS or subscribe to any of its journals. In contrast, the majority of presenters at the TWS 2000 Annual Conference were research biologists and members of TWS. The failure of many federal wildlife biologists to read scientific literature or attend professional meetings indicates a failure to promote the importance of continuing education in the federal workplace. I identify 2 potential adverse impacts of this failing: an inability to recognize important and relevant scientific contributions and an ineffectiveness in carrying out adaptive management.","language":"English","publisher":"Wiley","usgsCitation":"Schmutz, J.A., 2002, Educational background and professional participation by federal wildlife biologists: Implications for science, management, and The Wildlife Society: Wildlife Society Bulletin, v. 30, no. 2, p. 594-598.","productDescription":"5 p.","startPage":"594","endPage":"598","costCenters":[{"id":114,"text":"Alaska Science Center","active":true,"usgs":true}],"links":[{"id":233235,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":337974,"rank":2,"type":{"id":15,"text":"Index Page"},"url":"https://www.jstor.org/stable/3784520"}],"volume":"30","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a05aee4b0c8380cd50edc","contributors":{"authors":[{"text":"Schmutz, Joel A. 0000-0002-6516-0836 jschmutz@usgs.gov","orcid":"https://orcid.org/0000-0002-6516-0836","contributorId":1805,"corporation":false,"usgs":true,"family":"Schmutz","given":"Joel","email":"jschmutz@usgs.gov","middleInitial":"A.","affiliations":[{"id":114,"text":"Alaska Science Center","active":true,"usgs":true},{"id":117,"text":"Alaska Science Center Biology WTEB","active":true,"usgs":true}],"preferred":true,"id":401913,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70024640,"text":"70024640 - 2002 - Crosswell seismic investigation of hydraulically conductive, fracture bedrock near Mirror Lake, New Hampshire","interactions":[],"lastModifiedDate":"2018-11-26T09:53:27","indexId":"70024640","displayToPublicDate":"2002-01-01T00:00:00","publicationYear":"2002","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2165,"text":"Journal of Applied Geophysics","active":true,"publicationSubtype":{"id":10}},"title":"Crosswell seismic investigation of hydraulically conductive, fracture bedrock near Mirror Lake, New Hampshire","docAbstract":"Near Mirror Lake, New Hampshire (USA), hydraulically conductive, fractured bedrock was investigated with the crosswell seismic method to determine whether this method could provide any information about hydraulic conductivity between wells. To this end, crosswell seismic data, acoustic logs from boreholes, image logs from boreholes, and single borehole hydraulic tests were analyzed. The analysis showed that, first, the P-wave velocities from the acoustic logs tended to be higher in schist than they were in granite. (Schist and granite were the dominant rock types). Second, the P-wave velocities from the acoustic logs tended to be low near fractures. Third, the hydraulic conductivity was always low (always less than to 10−8 m/s) where no fractures intersected the borehole, but the hydraulic conductivity ranged from low to high (from less than to 10−10 m/s to 10−4 m/s) where one or more fractures intersected the borehole. Fourth, high hydraulic conductivities were slightly more frequent when the P-wave velocity was low (less than 5200 m/s) than when it was high (greater than or equal to 5200 m/s). The interpretation of this statistical relation was that the fractures tended to increase the hydraulic conductivity and to lower the P-wave velocity. This statistical relation was applied to a velocity tomogram to create a map showing the probability of high hydraulic conductivity; the map was consistent with results from independent hydraulic tests.
The NED is a seamless raster dataset from the USGS that fulfills many of the concepts of framework geospatial data as envisioned for the NSDI, allowing users to focus on analysis rather than data preparation. It is regularly maintained and updated, and it provides basic elevation data for many GIS applications. The NED is one of several seamless datasets that the USGS is making available through the Web. The techniques and approaches developed for producing, maintaining, and distributing the NED are the type that will be used for implementing the USGS National Map (http://nationalmap.usgs.gov/).
Double-crested cormorants (Phalacrocorax auritus) and boats of 2 length classes (≤ 8 m and > 8 m) were counted from a boat along 31 established strip transects in western Lake Erie from 24 April to 1 September 2000. Each transect included only one of the following habitats: (1) offshore of a breeding island or roosting/loafing area for cormorants (“refuge”), (2) reefs or shoals, (3) open water, or (4) offshore of an island shoreline that had evidence of development by humans. Foraging cormorants were recorded most often offshore of refuges and least often on open water. There was no difference between the numbers of foraging cormorants/km2 recorded offshore of developed shorelines and on reefs and shoals. More than half of all boats recorded were on transects that were within 1 km of developed shorelines. Among those transects > 1 km from developed shorelines, there were no differences among the habitats for the number of boats of either length class. The respective ranks of the 31 transect means of the numbers of cormorants/km2 and the numbers of boats/km2 in either length class were uncorrelated. The results suggest that (1) cormorants select foraging habitats based mainly on shoreline type, distance from shoreline, and depth, and (2) the amount of boat traffic is influenced by proximity to port and trip objectives, including sport angling and recreational boating. Although there is overlap in habitat use by cormorants and humans, this overlap is not complete. The perception of cormorants as a threat to fish populations may in part be due to this overlap.
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