Rates of foreshock occurrence involving shallow M ≥ 6 and M ≥ 7 mainshocks and M ≥ 5 foreshocks were measured in two worldwide catalogs over ∼20-year intervals. The overall rates observed are similar to ones measured in previous worldwide and regional studies when they are normalized for the ranges of magnitude difference they each span. The observed worldwide rates were compared to a generic model of earthquake clustering based on patterns of small and moderate aftershocks in California. The aftershock model was extended to the case of moderate foreshocks preceding large mainshocks. Overall, the observed worldwide foreshock rates exceed the extended California generic model by a factor of ∼2. Significant differences in foreshock rate were found among subsets of earthquakes defined by their focal mechanism and tectonic region, with the rate before thrust events higher and the rate before strike-slip events lower than the worldwide average. Among the thrust events, a large majority, composed of events located in shallow subduction zones, had a high foreshock rate, while a minority, located in continental thrust belts, had a low rate. These differences may explain why previous surveys have found low foreshock rates among thrust events in California (especially southern California), while the worldwide observations suggests the opposite: California, lacking an active subduction zone in most of its territory, and including a region of mountain-building thrusts in the south, reflects the low rate apparently typical for continental thrusts, while the worldwide observations, dominated by shallow subduction zone events, are foreshock-rich. If this is so, then the California generic model may significantly underestimate the conditional probability for a very large (M ≥ 8) earthquake following a potential (M ≥ 7) foreshock in Cascadia. The magnitude differences among the identified foreshock-mainshock pairs in the Harvard catalog are consistent with a uniform distribution over the range of observation.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/1998JB900089","issn":"01480227","usgsCitation":"Reasenberg, P., 1999, Foreshock occurrence before large earthquakes: Journal of Geophysical Research B: Solid Earth, v. 104, no. B3, p. 4755-4768, https://doi.org/10.1029/1998JB900089.","productDescription":"14 p.","startPage":"4755","endPage":"4768","numberOfPages":"14","costCenters":[],"links":[{"id":229560,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"104","issue":"B3","noUsgsAuthors":false,"publicationDate":"1999-03-10","publicationStatus":"PW","scienceBaseUri":"505a1322e4b0c8380cd54535","contributors":{"authors":[{"text":"Reasenberg, P.A.","contributorId":19959,"corporation":false,"usgs":true,"family":"Reasenberg","given":"P.A.","email":"","affiliations":[],"preferred":false,"id":391092,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":1000871,"text":"1000871 - 1999 - Functional convergence among pelagic sculpins of Lake Baikal and deepwater ciscoes of the Great Lakes","interactions":[],"lastModifiedDate":"2016-04-04T10:52:59","indexId":"1000871","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2330,"text":"Journal of Great Lakes Research","active":true,"publicationSubtype":{"id":10}},"title":"Functional convergence among pelagic sculpins of Lake Baikal and deepwater ciscoes of the Great Lakes","docAbstract":"The vast, well-oxygenated hypolimnia of Lake Baikal and the Great Lakes were both dominated by endemic planktivorous fishes. These dominants, two species of sculpins (Comephorus, Comephoridae) in Lake Baikal and six species of deepwater ciscoes (Coregonus, Salmonidae) in the Great Lakes, although distant taxonomically, have morphologies suggesting a surprising degree of functional convergence. Here it is proposed that the same two buoyancy-regulation strategies observed in Baikal sculpins also arose in the deepwater ciscoes of the Great Lakes. One strategy favors hydrostatic lift (generated by low specific gravity) and is characterized by fatter, larger-bodied fish with smaller paired fins; the second strategy favors hydrodynamic lift (generated by swimming) and is characterized by leaner, smaller-bodied fish with larger paired fins. Both types likely evolved to feed on a single species of ecologically analogous, vertically migrating macrozooplankter: Macrohectopus branickii in Lake Baikal and Mysis relicta in the Great Lakes. It is suggested that Coregonus did not diversify and proliferate in Lake Baikal as they did in the Great Lakes because by the time Coregonus colonized Lake Baikal, pelagic sculpins were already dominant.
","language":"English","publisher":"Elsevier","doi":"10.1016/S0380-1330(99)70782-3","usgsCitation":"Eshenroder, R., Sideleva, V.G., and Todd, T.N., 1999, Functional convergence among pelagic sculpins of Lake Baikal and deepwater ciscoes of the Great Lakes: Journal of Great Lakes Research, v. 25, no. 4, p. 847-855, https://doi.org/10.1016/S0380-1330(99)70782-3.","productDescription":"9 p.","startPage":"847","endPage":"855","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":324,"text":"Great Lakes Science Center","active":true,"usgs":true}],"links":[{"id":128695,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"25","issue":"4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4b30e4b07f02db6b40ad","contributors":{"authors":[{"text":"Eshenroder, Randy L.","contributorId":86716,"corporation":false,"usgs":true,"family":"Eshenroder","given":"Randy L.","affiliations":[],"preferred":false,"id":309680,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Sideleva, Valentina G.","contributorId":98670,"corporation":false,"usgs":true,"family":"Sideleva","given":"Valentina","email":"","middleInitial":"G.","affiliations":[],"preferred":false,"id":309681,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Todd, Thomas N.","contributorId":42547,"corporation":false,"usgs":true,"family":"Todd","given":"Thomas","email":"","middleInitial":"N.","affiliations":[],"preferred":false,"id":309679,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70021770,"text":"70021770 - 1999 - Geodetic estimates of fault slip rates in the San Francisco Bay area","interactions":[],"lastModifiedDate":"2024-07-17T15:25:27.312028","indexId":"70021770","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","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":"Geodetic estimates of fault slip rates in the San Francisco Bay area","docAbstract":"Bourne et al. [1998] have suggested that the interseismic velocity profile at the surface across a transform plate boundary is a replica of the secular velocity profile at depth in the plastosphere. On the other hand, in the viscoelastic coupling model the shape of the interseismic surface velocity profile is a consequence of plastosphere relaxation following the previous rupture of the faults that make up the plate boundary and is not directly related to the secular flow in the plastosphere. The two models appear to be incompatible. If the plate boundary is composed of several subparallel faults and the interseismic surface velocity profile across the boundary known, each model predicts the secular slip rates on the faults which make up the boundary. As suggested by Bourne et al., the models can then be tested by comparing the predicted secular slip rates to those estimated from long-term offsets inferred from geology. Here we apply that test to the secular slip rates predicted for the principal faults (San Andreas, San Gregorio, Hayward, Calaveras, Rodgers Creek, Green Valley and Greenville faults) in the San Andreas fault system in the San Francisco Bay area. The estimates from the two models generally agree with one another and to a lesser extent with the geologic estimate. Because the viscoelastic coupling model has been equally successful in estimating secular slip rates on the various fault strands at a diffuse plate boundary, the success of the model of Bourne et at. [1998] in doing the same thing should not be taken as proof that the interseismic velocity profile across the plate boundary at the surface is a replica of the velocity profile at depth in the plastosphere.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/1998JB900108","issn":"01480227","usgsCitation":"Savage, J., Svarc, J.L., and Prescott, W., 1999, Geodetic estimates of fault slip rates in the San Francisco Bay area: Journal of Geophysical Research B: Solid Earth, v. 104, no. B3, p. 4995-5002, https://doi.org/10.1029/1998JB900108.","productDescription":"8 p.","startPage":"4995","endPage":"5002","numberOfPages":"8","costCenters":[],"links":[{"id":229523,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"104","issue":"B3","noUsgsAuthors":false,"publicationDate":"1999-03-10","publicationStatus":"PW","scienceBaseUri":"505a173be4b0c8380cd55435","contributors":{"authors":[{"text":"Savage, J.C. 0000-0002-5114-7673","orcid":"https://orcid.org/0000-0002-5114-7673","contributorId":102876,"corporation":false,"usgs":true,"family":"Savage","given":"J.C.","affiliations":[],"preferred":false,"id":391091,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Svarc, J. L.","contributorId":75995,"corporation":false,"usgs":true,"family":"Svarc","given":"J.","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":391089,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Prescott, W.H.","contributorId":96337,"corporation":false,"usgs":true,"family":"Prescott","given":"W.H.","email":"","affiliations":[],"preferred":false,"id":391090,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":1000503,"text":"1000503 - 1999 - Co-existence of zebra mussels and freshwater unionids: Population dynamics of Leptodea fragilis in a coastal wetland infested with zebra mussels","interactions":[],"lastModifiedDate":"2016-04-04T11:38:46","indexId":"1000503","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1176,"text":"Canadian Journal of Zoology","active":true,"publicationSubtype":{"id":10}},"title":"Co-existence of zebra mussels and freshwater unionids: Population dynamics of Leptodea fragilis in a coastal wetland infested with zebra mussels","docAbstract":"In 1996, thousands of live Leptodea fragilis were collected from a marsh located in the western basin of Lake Erie that was infested with zebra mussels (Dreissena polymorpha). Despite the presence of zebra mussels at this site for a number of years, this L. fragilis population showed no signs of competition-induced changes in population dynamics. Biofouling was limited: fewer than 1% of the L. fragilis showed evidence of recent or past zebra mussel colonization. Successful recruitment occurred yearly, with multiple year classes collected that ranged in age from 1 to 12 years. However, age and shell length were not well correlated. Seventy-one percent of the individuals collected were 51-80 mm long, but ranged in age from 2 to 4.5 years. Three different patterns of growth or shell deposition were found. Some individuals grew rapidly, reaching 105 mm in 3.5 years, while others grew only 4.5 mm over the same time period. A few grew poorly during some years but very rapidly in others. Individuals with a shell length of 41 mm or more were sexually mature and females were more common than males. The strong recruitment and steady growth of this population showed no change between the years before and after the zebra mussel invasion, indicating that this marsh is functioning as a natural refugium from potential problems caused by zebra mussels.
","language":"English","publisher":"NRC Research Press","doi":"10.1139/z98-241","usgsCitation":"Nichols, S.J., and Amberg, J., 1999, Co-existence of zebra mussels and freshwater unionids: Population dynamics of Leptodea fragilis in a coastal wetland infested with zebra mussels: Canadian Journal of Zoology, v. 77, no. 3, p. 423-432, https://doi.org/10.1139/z98-241.","productDescription":"10 p.","startPage":"423","endPage":"432","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":324,"text":"Great Lakes Science Center","active":true,"usgs":true}],"links":[{"id":131627,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"77","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e49d6e4b07f02db5de073","contributors":{"authors":[{"text":"Nichols, S. Jerrine","contributorId":25887,"corporation":false,"usgs":true,"family":"Nichols","given":"S.","email":"","middleInitial":"Jerrine","affiliations":[],"preferred":false,"id":308648,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Amberg, Jon","contributorId":82266,"corporation":false,"usgs":true,"family":"Amberg","given":"Jon","affiliations":[],"preferred":false,"id":308649,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":1015995,"text":"1015995 - 1999 - Clinal variation in the juvenal plumage of American kestrels","interactions":[],"lastModifiedDate":"2012-02-02T00:04:49","indexId":"1015995","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2284,"text":"Journal of Field Ornithology","active":true,"publicationSubtype":{"id":10}},"title":"Clinal variation in the juvenal plumage of American kestrels","docAbstract":"The American Kestrel(Falco sparverius) is a sexually dichromatic falcon that exhibits\r\nconsiderable individual plumage variability. For example, the anterior extent of the\r\nblack dorsal barring in juvenile males has been used throughout North America as one of\r\nseveral aging criteria, but recent data demonstrate that the variability among individual\r\nSoutheastern American Kestrels(E S. paulus)exceeds that accounted for by age. The objective of this study was to search for geographic patterns in the variability of juvenal plumage, particularly those characteristics considered indicative of age. Nestling kestrels (n = 610)\r\nwere examined prior to fledging during the 1997 breeding season at nest box programs\r\nacross a large portion of the North American breeding range. From south to north (1) the\r\ncrown patches of both males and females become more completely rufous, and (2) shaft\r\nstreaks on forehead and crown feathers become more pronounced, especially in males. Male\r\nSoutheastern American Kestrels differed from other males (E s. sparverius) in that the anterior\r\nextent of dorsal barring averaged less but was more variable. The variability observed\r\nin North America appears to be part of a cline extending across the species range in the\r\nWestern Hemisphere, where tropical subspecies are small and have reduced dorsal barring.\r\nBoth body size and, especially in males, dorsal barring increases with increasing north and\r\nsouth latitude. We suggest that this geographic pattern is adaptive in terms of thermoregulation, and that differences in the sex roles may explain why males become less barred with maturity while females do not.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of Field Ornithology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","usgsCitation":"Smallwood, J., Natale, C., Steenhof, K., Meetz, M., Marti, C., Melvin, R., Bortolotti, G., Robertson, R., Robertson, S., Shuford, W., Lindemann, S., and Tornwall, B., 1999, Clinal variation in the juvenal plumage of American kestrels: Journal of Field Ornithology, v. 70, no. 3, p. 425-435.","productDescription":"p. 425-435","startPage":"425","endPage":"435","numberOfPages":"11","costCenters":[{"id":290,"text":"Forest and Rangeland Ecosystem Science Center","active":false,"usgs":true}],"links":[{"id":134465,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"70","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e49cfe4b07f02db5da881","contributors":{"authors":[{"text":"Smallwood, J.A.","contributorId":13945,"corporation":false,"usgs":true,"family":"Smallwood","given":"J.A.","email":"","affiliations":[],"preferred":false,"id":323467,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Natale, C.","contributorId":49762,"corporation":false,"usgs":true,"family":"Natale","given":"C.","email":"","affiliations":[],"preferred":false,"id":323474,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Steenhof, K.","contributorId":98696,"corporation":false,"usgs":true,"family":"Steenhof","given":"K.","affiliations":[],"preferred":false,"id":323477,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Meetz, M.","contributorId":28215,"corporation":false,"usgs":true,"family":"Meetz","given":"M.","email":"","affiliations":[],"preferred":false,"id":323469,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Marti, C.D.","contributorId":31359,"corporation":false,"usgs":true,"family":"Marti","given":"C.D.","email":"","affiliations":[],"preferred":false,"id":323470,"contributorType":{"id":1,"text":"Authors"},"rank":5},{"text":"Melvin, R.J.","contributorId":40184,"corporation":false,"usgs":true,"family":"Melvin","given":"R.J.","email":"","affiliations":[],"preferred":false,"id":323472,"contributorType":{"id":1,"text":"Authors"},"rank":6},{"text":"Bortolotti, G.R.","contributorId":12437,"corporation":false,"usgs":true,"family":"Bortolotti","given":"G.R.","email":"","affiliations":[],"preferred":false,"id":323466,"contributorType":{"id":1,"text":"Authors"},"rank":7},{"text":"Robertson, R.","contributorId":45279,"corporation":false,"usgs":true,"family":"Robertson","given":"R.","email":"","affiliations":[],"preferred":false,"id":323473,"contributorType":{"id":1,"text":"Authors"},"rank":8},{"text":"Robertson, S.","contributorId":34484,"corporation":false,"usgs":true,"family":"Robertson","given":"S.","email":"","affiliations":[],"preferred":false,"id":323471,"contributorType":{"id":1,"text":"Authors"},"rank":9},{"text":"Shuford, W.R.","contributorId":75499,"corporation":false,"usgs":true,"family":"Shuford","given":"W.R.","email":"","affiliations":[],"preferred":false,"id":323475,"contributorType":{"id":1,"text":"Authors"},"rank":10},{"text":"Lindemann, S.A.","contributorId":21128,"corporation":false,"usgs":true,"family":"Lindemann","given":"S.A.","email":"","affiliations":[],"preferred":false,"id":323468,"contributorType":{"id":1,"text":"Authors"},"rank":11},{"text":"Tornwall, B.","contributorId":77118,"corporation":false,"usgs":true,"family":"Tornwall","given":"B.","email":"","affiliations":[],"preferred":false,"id":323476,"contributorType":{"id":1,"text":"Authors"},"rank":12}]}} ,{"id":70021769,"text":"70021769 - 1999 - Runoff and erosion response of simulated waste burial covers in a semi-arid environment","interactions":[],"lastModifiedDate":"2012-03-12T17:19:41","indexId":"70021769","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2529,"text":"Journal of the American Water Resources Association","active":true,"publicationSubtype":{"id":10}},"title":"Runoff and erosion response of simulated waste burial covers in a semi-arid environment","docAbstract":"Control of runoff (reducing infiltration) and erosion at shallow land burials is necessary in order to assure environmentally safe disposal of low-level radioactive-waste and other waste products. This study evaluated the runoff and erosion response of two perennial grass species on simulated waste burial covers at Idaho National Engineering and Environmental Laboratory (INEEL). Rainfall simulations were applied to three plots covered by crested wheatgrass [Agropyron desertorum (Fischer ex Link) Shultes], three plots covered by streambank wheatgrass [Elymus lanceolatus (Scribner and Smith) Gould spp. lanceolatus], and one bare plot. Average total runoff for rainfall simulations in 1987, 1989, and 1990 was 42 percent greater on streambank wheatgrass plots than on crested wheatgrass plots. Average total soil loss for rainfall simulations in 1987 and 1990 was 105 percent greater on streambank wheatgrass plots than on crested wheatgrass plots. Total runoff and soil loss from natural rainfall and snowmelt events during 1987 were 25 and 105 percent greater, respectively, on streambank wheatgrass plots than on crested wheatgrass plots. Thus, crested wheatgrass appears to be better suited in revegetation of waste burial covers at INEEL than streambank wheatgrass due to its much lower erosion rate and only slightly higher infiltration rate (lower runoff rate).","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Journal of the American Water Resources Association","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"American Water Resources Assoc","publisherLocation":"Herndon, VA, United States","issn":"1093474X","usgsCitation":"Bent, G., Goff, B., Rightmire, K., and Sidle, R., 1999, Runoff and erosion response of simulated waste burial covers in a semi-arid environment: Journal of the American Water Resources Association, v. 35, no. 2, p. 441-455.","startPage":"441","endPage":"455","numberOfPages":"15","costCenters":[],"links":[{"id":229522,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"35","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505aaebee4b0c8380cd871cd","contributors":{"authors":[{"text":"Bent, G.C.","contributorId":81645,"corporation":false,"usgs":true,"family":"Bent","given":"G.C.","email":"","affiliations":[],"preferred":false,"id":391087,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Goff, B.F.","contributorId":101820,"corporation":false,"usgs":true,"family":"Goff","given":"B.F.","email":"","affiliations":[],"preferred":false,"id":391088,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Rightmire, K.G.","contributorId":34285,"corporation":false,"usgs":true,"family":"Rightmire","given":"K.G.","email":"","affiliations":[],"preferred":false,"id":391085,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Sidle, R.C.","contributorId":47934,"corporation":false,"usgs":true,"family":"Sidle","given":"R.C.","email":"","affiliations":[],"preferred":false,"id":391086,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70021759,"text":"70021759 - 1999 - Assessing groundwater vulnerability to agrichemical contamination in the Midwest US","interactions":[],"lastModifiedDate":"2018-12-19T10:13:09","indexId":"70021759","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3724,"text":"Water Science and Technology","active":true,"publicationSubtype":{"id":10}},"title":"Assessing groundwater vulnerability to agrichemical contamination in the Midwest US","docAbstract":"Agrichemicals (herbicides and nitrate) are significant sources of diffuse pollution to groundwater. Indirect methods are needed to assess the potential for groundwater contamination by diffuse sources because groundwater monitoring is too costly to adequately define the geographic extent of contamination at a regional or national scale. This paper presents examples of the application of statistical, overlay and index, and process-based modeling methods for groundwater vulnerability assessments to a variety of data from the Midwest U.S. The principles for vulnerability assessment include both intrinsic (pedologic, climatologic, and hydrogeologic factors) and specific (contaminant and other anthropogenic factors) vulnerability of a location. Statistical methods use the frequency of contaminant occurrence, contaminant concentration, or contamination probability as a response variable. Statistical assessments are useful for defining the relations among explanatory and response variables whether they define intrinsic or specific vulnerability. Multivariate statistical analyses are useful for ranking variables critical to estimating water quality responses of interest. Overlay and index methods involve intersecting maps of intrinsic and specific vulnerability properties and indexing the variables by applying appropriate weights. Deterministic models use process-based equations to simulate contaminant transport and are distinguished from the other methods in their potential to predict contaminant transport in both space and time. An example of a one-dimensional leaching model linked to a geographic information system (GIS) to define a regional metamodel for contamination in the Midwest is included.
","language":"English","publisher":"IWA","doi":"10.1016/S0273-1223(99)00042-6","issn":"02731223","usgsCitation":"Burkart, M.R., Kolpin, D., and James, D., 1999, Assessing groundwater vulnerability to agrichemical contamination in the Midwest US: Water Science and Technology, v. 39, no. 3, p. 103-112, https://doi.org/10.1016/S0273-1223(99)00042-6.","productDescription":"10 p.","startPage":"103","endPage":"112","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":351,"text":"Iowa Water Science Center","active":true,"usgs":true},{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":229403,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":206315,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0273-1223(99)00042-6"}],"country":"United States","volume":"39","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059edd6e4b0c8380cd49a39","contributors":{"authors":[{"text":"Burkart, M. R.","contributorId":42190,"corporation":false,"usgs":true,"family":"Burkart","given":"M.","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":391046,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Kolpin, D.W.","contributorId":87565,"corporation":false,"usgs":true,"family":"Kolpin","given":"D.W.","email":"","affiliations":[],"preferred":false,"id":391047,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"James, D.E.","contributorId":22927,"corporation":false,"usgs":true,"family":"James","given":"D.E.","email":"","affiliations":[],"preferred":false,"id":391045,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70021731,"text":"70021731 - 1999 - Estimates of suspended-sediment flux and bedform activity on the inner portion of the Eel continental shelf","interactions":[],"lastModifiedDate":"2012-03-12T17:19:41","indexId":"70021731","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2667,"text":"Marine Geology","active":true,"publicationSubtype":{"id":10}},"title":"Estimates of suspended-sediment flux and bedform activity on the inner portion of the Eel continental shelf","docAbstract":"Energetic waves, strong bottom currents, and relatively high rates of sediment discharge from the Eel River combined to produce large amounts of suspended-sediment transport on the inner continental shelf near the Eel River during the winter of 1995-1996. Bottom-boundary-layer (BBL) measurements at a depth of ~50 m using the GEOPROBE tripod showed that the strongest near-bottom flows (combined wave and current speeds of over 1 m/s) and highest sediment concentrations (exceeding 2 g/l at ~1.2 m above the bed) occurred during two storms, one in December 1995 and the other in February 1996. Discharge from the Eel River during these storms was estimated at between 2 and 4 x 103 m3/s. Suspended-sediment flux (SSF) was measured 1.2 m above the bed and calculated throughout the BBL, by applying the tripod data to a shelf sediment-transport model. These results showed initially northward along-shelf SSF during the storms, followed by abrupt and persistent southward reversals. Along-shelf flux was more pronounced during and after the December storm than in February. Across-shelf SSF over the entire measurement period was decidedly seaward. This seaward transport could be responsible for surficial deposits of recent sediment on the outer shelf and upper continental slope in this region. Sediment ripples and larger bedforms were observed in the very fine to fine sand at 50-m depth using a sector-scanning sonar mounted on the tripod. Ripple wavelengths estimated from the sonar images were about 9 cm, which compared favorably with photographs of the bottom taken with a camera mounted on the tripod. The ripple patterns were stable during periods of low combined wave-current bottom stresses, but changed significantly during high-stress events, such as the February storm. Two different sonic altimeters recorded changes in bed elevation of 10 to 20 cm during the periods of measurement. These changes are thought to have been caused principally by the migration of low-amplitude, long-wavelength sand waves into the measurement area.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Marine Geology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","doi":"10.1016/S0025-3227(98)00105-4","issn":"00253227","usgsCitation":"Cacchione, D., Wiberg, P., Lynch, J., Irish, J., and Traykovski, P., 1999, Estimates of suspended-sediment flux and bedform activity on the inner portion of the Eel continental shelf: Marine Geology, v. 154, no. 1-4, p. 83-97, https://doi.org/10.1016/S0025-3227(98)00105-4.","startPage":"83","endPage":"97","numberOfPages":"15","costCenters":[],"links":[{"id":206342,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/S0025-3227(98)00105-4"},{"id":229482,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"154","issue":"1-4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a0af2e4b0c8380cd524cd","contributors":{"authors":[{"text":"Cacchione, D.A.","contributorId":65448,"corporation":false,"usgs":true,"family":"Cacchione","given":"D.A.","affiliations":[{"id":520,"text":"Pacific Coastal and Marine Science Center","active":true,"usgs":true}],"preferred":false,"id":390942,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Wiberg, P.L.","contributorId":33827,"corporation":false,"usgs":true,"family":"Wiberg","given":"P.L.","email":"","affiliations":[],"preferred":false,"id":390941,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Lynch, J.","contributorId":90896,"corporation":false,"usgs":true,"family":"Lynch","given":"J.","email":"","affiliations":[],"preferred":false,"id":390944,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Irish, J.","contributorId":92450,"corporation":false,"usgs":true,"family":"Irish","given":"J.","email":"","affiliations":[],"preferred":false,"id":390945,"contributorType":{"id":1,"text":"Authors"},"rank":4},{"text":"Traykovski, P.","contributorId":76484,"corporation":false,"usgs":true,"family":"Traykovski","given":"P.","affiliations":[],"preferred":false,"id":390943,"contributorType":{"id":1,"text":"Authors"},"rank":5}]}} ,{"id":70021694,"text":"70021694 - 1999 - Geologic continuous casting below continental and deep-sea detachment faults and at the striated extrusion of Sacsayhuaman, Peru","interactions":[],"lastModifiedDate":"2024-01-05T12:24:49.503199","indexId":"70021694","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1796,"text":"Geology","active":true,"publicationSubtype":{"id":10}},"title":"Geologic continuous casting below continental and deep-sea detachment faults and at the striated extrusion of Sacsayhuaman, Peru","docAbstract":"In one common type of industrial continuous casting, partially molten metal is extruded from a vessel through a shaped orifice called a mold in which the metal assumes the cross-sectional form of the mold as it cools and solidifies. Continuous casting can be sustained as long as molten metal is supplied and thermal conditions are maintained. I propose that a similar process produced parallel sets of grooves in three geologic settings, as follows: (1) corrugated metamorphic core complexes where mylonitized mid-crustal rocks were exhumed by movement along low-angle normal faults known as detachment faults; (2) corrugated submarine surfaces where ultramafic and mafic rocks were exhumed by normal faulting within oceanic spreading centers; and (3) striated magma extrusions exemplified by the famous grooved outcrops at the Inca fortress of Sacsayhuamán in Peru. In each case, rocks inferred to have overlain the corrugated surface during corrugation genesis molded and shaped a plastic to partially molten rock mass as it was extruded from a moderate- to high-temperature reservoir.
The taxonomic status of the Arizona myotis (Myotis occultus) is uncertain. Although the taxon was described as a distinct species and currently is regarded as such by some authors, others have noted what they interpreted as intergradation with the little brown bat (M. lucifugus carissima) near the Colorado-New Mexico state line. In this study, we used protein electrophoresis to compare bats of these nominal taxa. We examined 20 loci from 142 specimens referable to M. occultus and M. lucifugus from New Mexico, Colorado, and Wyoming. Nine of the 20 loci were polymorphic. Results show that there were high similarities among samples, no fixed alleles, and minor divergence from Hardy-Weinberg equilibrium. Our results suggest that the two nominal taxa represent only one species and that M. occultus should be regarded as a subspecies of M. lucifugus.
","language":"English","publisher":"Oxford Academic","doi":"10.2307/1383300","issn":"00222372","usgsCitation":"Valdez, E., Choate, J.R., Bogan, M., and Yates, T.L., 1999, Taxonomic status of Myotis occultus: Journal of Mammalogy, v. 80, no. 2, p. 545-552, https://doi.org/10.2307/1383300.","productDescription":"8 p.","startPage":"545","endPage":"552","costCenters":[],"links":[{"id":487283,"rank":1,"type":{"id":41,"text":"Open Access External Repository Page"},"url":"https://scholars.fhsu.edu/sternberg_facpubs/6","text":"External Repository"},{"id":229143,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"80","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505ba3f0e4b08c986b31ffca","contributors":{"authors":[{"text":"Valdez, E.W.","contributorId":13581,"corporation":false,"usgs":true,"family":"Valdez","given":"E.W.","email":"","affiliations":[],"preferred":false,"id":390575,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Choate, Jerry R.","contributorId":47109,"corporation":false,"usgs":true,"family":"Choate","given":"Jerry","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":390577,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Bogan, M.A.","contributorId":17939,"corporation":false,"usgs":true,"family":"Bogan","given":"M.A.","email":"","affiliations":[],"preferred":false,"id":390576,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Yates, Terry L.","contributorId":87489,"corporation":false,"usgs":false,"family":"Yates","given":"Terry","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":390578,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70021638,"text":"70021638 - 1999 - Sequential filling of a late paleozoic foreland basin","interactions":[],"lastModifiedDate":"2024-05-14T00:06:30.986407","indexId":"70021638","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2451,"text":"Journal of Sedimentary Research","onlineIssn":"1938-3681","printIssn":"1527-1404","active":true,"publicationSubtype":{"id":10}},"title":"Sequential filling of a late paleozoic foreland basin","docAbstract":"Through the use of an extensive data base of geophysical well logs, parasequence-scale subdivisions within a late Paleozoic synorogenic clastic wedge resolve cycles of sequential subsidence of a foreland basin, sediment progradation, subsidence of a carbonate shelf edge, diachronously subsiding discrete depositional centers, and basinwide transgression. Although temporal resolution of biostratigraphic markers is less precise in Paleozoic successions than in younger basins, parasequence-scale subdivisions provide more detailed resolution within marker-defined units in Paleozoic strata. As an example, the late Paleozoic Black Warrior basin in the foreland of the Ouachita thrust belt is filled with a synorogenic clastic wedge, the lower part of which intertongues with the fringe of a cratonic carbonate facies in the distal part of the basin. The stratal geometry of one tongue of the carbonate facies (lower tongue of Bangor Limestone) defines a ramp that grades basinward into a thin black shale. An overlying tongue of the synorogenic clastic wedge (lower tongue of Parkwood Formation) consists of cyclic delta and delta-front deposits, in which parasequences are defined by marine-flooding surfaces above coarsening- and shallowing-upward successions of mudstone and sandstone. Within the lower Parkwood tongue, two genetic stratigraphic sequences (A and B) are defined by parasequence offlap and downlap patterns and are bounded at the tops by basinwide maximum-flooding surfaces. The distribution of parasequences within sequences A and B indicates two cycles of sequential subsidence (deepening) and progradation, suggesting subsidence during thrust advance and progradation during thrust quiescence. Parasequence stacking in sequences A and B also indicates diachronous differential tectonic subsidence of two discrete depositional centers within the basin. The uppermost sequence (C) includes reworked sandstones and an overlying shallow-marine limestone, a vertical succession that reflects no tectonic subsidence, a very minor or null sediment supply, and basinwide transgression. The temporal resolution at parasequence scale significantly improves the resolution of the tectonic history of the thrust belt-foreland basin system.
Seeds of 22 species collected from recently burned phrygana were tested for their response to fire-type cues of charred wood and heat-shock. All Cistus species were stimulated by brief heat-shock, as shown in previous studies; however, none responded to charred wood. Only one of the 22 species was stimulated by charred wood, and only in dark-inhibited seeds, and this response did not occur in the light. The lack of charred-wood-induced germination is in contrast to the substantial proportion of species with this germination response reported for mediterranean-type vegetation in California, the Cape region of South Africa, and Western Australia. Phrygana has many species with heat-shock-stimulated germination, primarily in the Fabaceae and Cistaceae. This germination cue is widespread in these two families, thus, the presence of heat-shock-stimulated germination is a result of homologous, rather than covergent, adaptations in mediterranean-climate ecosystems. Germination response to light was not randomly distributed with respect to fire-type response. Heat-shock-stimulated species were almost uniformly light neutral, in contrast to more opportunistic colonizing species with non-refractory seeds, in which half of the species responded positively or negatively to light.
","language":"English","publisher":"Taylor and Francis","doi":"10.1080/07929978.1999.10676746","usgsCitation":"Keeley, J.E., and Babr-Keeley, M., 1999, Role of charred wood, heat-shock and light in germination of postfire phrygana species from the eastern Mediterranean Basin: Israel Journal of Plant Sciences, v. 47, no. 1, p. 11-16, https://doi.org/10.1080/07929978.1999.10676746.","productDescription":"6 p.","startPage":"11","endPage":"16","numberOfPages":"6","costCenters":[{"id":651,"text":"Western Ecological Research Center","active":true,"usgs":true}],"links":[{"id":131643,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"47","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a0ee4b07f02db5fe291","contributors":{"authors":[{"text":"Keeley, Jon E. 0000-0002-4564-6521 jon_keeley@usgs.gov","orcid":"https://orcid.org/0000-0002-4564-6521","contributorId":1268,"corporation":false,"usgs":true,"family":"Keeley","given":"Jon","email":"jon_keeley@usgs.gov","middleInitial":"E.","affiliations":[{"id":651,"text":"Western Ecological Research Center","active":true,"usgs":true}],"preferred":true,"id":316212,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Babr-Keeley, Melanie","contributorId":175076,"corporation":false,"usgs":false,"family":"Babr-Keeley","given":"Melanie","email":"","affiliations":[],"preferred":false,"id":316211,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70022080,"text":"70022080 - 1999 - Tools for groundwater protection planning: An example from McHenry County, Illinois, USA","interactions":[],"lastModifiedDate":"2012-03-12T17:19:46","indexId":"70022080","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1547,"text":"Environmental Management","active":true,"publicationSubtype":{"id":10}},"title":"Tools for groundwater protection planning: An example from McHenry County, Illinois, USA","docAbstract":"This paper presents an approach for producing aquifer sensitivity maps from three-dimensional geologic maps, called stack-unit maps. Stack-unit maps depict the succession of geologic materials to a given depth, and aquifer sensitivity maps interpret the successions according to their ability to transmit potential contaminants. Using McHenry County, Illinois, as a case study, stack-unit maps and an aquifer sensitivity assessment were made to help land-use planners, public health officials, consultants, developers, and the public make informed decisions regarding land use. A map of aquifer sensitivity is important for planning because the county is one of the fastest growing counties in the nation, and highly vulnerable sand and gravel aquifers occur within 6 m of ground surface over 75% of its area. The aquifer sensitivity map can provide guidance to regulators seeking optimal protection of groundwater resources where these resources are particularly vulnerable. In addition, the map can be used to help officials direct waste-disposal and industrial facilities and other sensitive land-use practices to areas where the least damage is likely to occur, thereby reducing potential future liabilities.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Environmental Management","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"Springer-Verlag New York","publisherLocation":"Secaucus, NJ, United States","doi":"10.1007/s002679900189","issn":"0364152X","usgsCitation":"Berg, R.C., Curry, B.B., and Olshansky, R., 1999, Tools for groundwater protection planning: An example from McHenry County, Illinois, USA: Environmental Management, v. 23, no. 3, p. 321-331, https://doi.org/10.1007/s002679900189.","startPage":"321","endPage":"331","numberOfPages":"11","costCenters":[],"links":[{"id":206656,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1007/s002679900189"},{"id":230478,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"23","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505bb43ce4b08c986b326271","contributors":{"authors":[{"text":"Berg, R. C.","contributorId":11673,"corporation":false,"usgs":true,"family":"Berg","given":"R.","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":392293,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Curry, B. Brandon","contributorId":104224,"corporation":false,"usgs":true,"family":"Curry","given":"B.","email":"","middleInitial":"Brandon","affiliations":[],"preferred":false,"id":392295,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Olshansky, R.","contributorId":101160,"corporation":false,"usgs":true,"family":"Olshansky","given":"R.","email":"","affiliations":[],"preferred":false,"id":392294,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70021962,"text":"70021962 - 1999 - Tributary stream infiltration as a source of herbicides in an alluvial aquifer","interactions":[],"lastModifiedDate":"2024-03-28T11:23:25.625444","indexId":"70021962","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","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":"Tributary stream infiltration as a source of herbicides in an alluvial aquifer","docAbstract":"Where Walnut Creek flows across the South Skunk River alluvial aquifer, it provides a potential source of herbicides and herbicide metabolites. This straightened reach of the creek loses water and dissolved contaminants to the alluvial aquifer through a layer of fine-grained flood plain deposits. Estimates of potential flux of chemicals were based on measurements taken during baseflow in April 1994 before herbicides were applied to the watershed and in June 1994 after chemical application and when stream discharge included runoff and tile-drainage water. Hydraulic head measurements between the creek and flood plain deposits and between the creek and aquifer confirmed the potential for downward groundwater flow during both sampling periods. Hydraulic conductivity estimates from slug tests were used to calculate an average linear groundwater velocity of 0.5 m d−1 in the fine-grained flood plain deposits. At this velocity, contaminants could be advectively transported to the aquifer within 6 d. The potential for atrazine (2-chloro-4-ethylamino-6-isopropylamino-s-triazine) flux to the aquifer from the creek was estimated to be between 60 and 3000 µg d−1 m−2. This rate is one to three orders of magnitude greater than the estimated flux via leaching beneath a typical field. If the process of vertical stream leakage occurs in many hydrologic settings, it may constitute a substantial source of herbicides to shallow alluvial aquifers in many areas of the Midwest.
Broadband teleseismic P waves have been analyzed to recover the rupture history of the large (MS 7.4) Colima-Jalisco, Mexico, shallow interplate thrust earthquake of 9 October 1995. Ground-displacement records in the period range of 1-60 sec are inverted using a linear, finite-fault waveform inversion procedure that allows a variable dislocation duration on a prescribed fault. The method is applied using both a narrow fault that simulates a line source with a dislocation window of 50 sec and a wide fault with a possible rise time of up to 20 sec that additionally allows slip updip and downdip from the hypocenter. The line-source analysis provides a spatio-temporal image of the slip distribution consisting of several large sources located northwest of the hypocenter and spanning a range of rupture velocities. The two-dimensional finite-fault inversion allows slip over this rupture-velocity range and indicates that the greatest coseismic displacement (3-4 m) is located between 70 and 130 km from the hypocenter at depths shallower than about 15 km. Slip in this shallow region consists of two major sources, one of which is delayed by about 10 sec relative to a coherent propagation of rupture along the plate interface. These two slip sources account for about one-third of the total P-wave seismic moment of 8.3 × 1027 dyne-cm (Mw 7.9) and may have been responsible for the local tsunami observed along the coast following the earthquake.
Three 60 m long, 2·8 m high snowfences have been erected to study long-term effects of changing winter snow conditions on arctic and alpine tundra. This paper describes the experimental design and short-term effects. Open-top fiberglass warming chambers are placed along the experimental snow gradients and in controls areas outside the fences; each warming plot is paired with an unwarmed plot. The purpose of the experiment is to examine short- and long-term changes to the integrated physical-biological systems under simultaneous changes of winter snow regime and summer temperature, as part of the Long-Term Ecological Research network and the International Tundra Experiment. The sites were at Niwot Ridge, Colorado, a temperate high altitude site in the Colorado Rockies, and Toolik Lake, Alaska, a high-latitude site. Initial results indicate that although experimental designs are essentially identical at the arctic and alpine sites, experimental effects are different. The drift at Niwot Ridge lasts much longer than do the Toolik Lake drifts, so that the Niwot Ridge fence affects both summer and winter conditions, whereas the Toolik Lake fence affects primarily winter conditions. The temperature experiment also differs in effect between the sites. Although the average temperature increase at the two sites is similar (daily increase 1·5 °C at Toolik and 1·9 °C at Niwot Ridge), at Toolik Lake there is only minor diurnal variation, whereas at Niwot Ridge the daytime increases are extreme on sunny days (as much as 7–10 °C), and minimum nighttime temperatures in the chambers are often slightly cooler than ambient (by about 1 °C). The experimental drifts resulted in wintertime increases in temperature and CO2 flux. Temperatures under the deep drifts were much more consistent and warmer than in control areas, and at Niwot Ridge remained very close to 0 °C all winter. These increased temperatures were likely responsible for observed increases in system carbon loss. Initial changes to the aboveground biotic system included an increase in growth in response to both snow and warming, despite a reduced growing season. This is expected to be a transient response that will eventually be replaced by reduced growth. At least one species, Kobresia myosuroides, had almost completely died at Niwot Ridge three years after fence construction, whereas other species were increasing. We expect in both the short- and long-term to see the strongest effects of snow at the Niwot Ridge site, and stronger effects of temperature at Toolik Lake.
We compared capture rates of Great Tits at funnel traps, where several birds can be captured at once so that some decoy effect may appear, to those obtained at automatic traps, where only one bird can be trapped at a time, at trapping stations in northeastern Spain. Juvenile birds were mainly captured at funnel traps (79% of juvenile captures), whereas adult plumaged birds were captured at both types of traps (51% of captures were at the funnel traps) (test between ages, P<0.001). Juvenile Great Tits had lower body condition as measured by ptilochronology (P<0.01). These birds are more easily trapped in funnel traps, which may be acting as decoy traps, and thus are vulnerable to the same kinds of biases (eg age or body condition) that have been previously documented for decoy traps.
","language":"English","publisher":"Taylor & Francis","doi":"10.1080/03078698.1999.9674189","issn":"03078698","usgsCitation":"Senar, J., Domenech, J., and Conroy, M., 1999, Funnel traps capture a higher proportion of juvenile Great Tits parus major than automatic traps: Ringing and Migration, v. 19, no. 4, p. 257-259, https://doi.org/10.1080/03078698.1999.9674189.","productDescription":"3 p.","startPage":"257","endPage":"259","numberOfPages":"3","costCenters":[],"links":[{"id":229947,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"19","issue":"4","noUsgsAuthors":false,"publicationDate":"2011-04-11","publicationStatus":"PW","scienceBaseUri":"505a141ce4b0c8380cd548f9","contributors":{"authors":[{"text":"Senar, J.C.","contributorId":73317,"corporation":false,"usgs":true,"family":"Senar","given":"J.C.","email":"","affiliations":[],"preferred":false,"id":389350,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Domenech, J.","contributorId":101364,"corporation":false,"usgs":true,"family":"Domenech","given":"J.","email":"","affiliations":[],"preferred":false,"id":389352,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Conroy, M.J.","contributorId":84690,"corporation":false,"usgs":true,"family":"Conroy","given":"M.J.","email":"","affiliations":[],"preferred":false,"id":389351,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70021522,"text":"70021522 - 1999 - Are shifts in herbicide use reflected in concentration changes in Midwestern rivers?","interactions":[],"lastModifiedDate":"2018-12-21T06:46:17","indexId":"70021522","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","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":"Are shifts in herbicide use reflected in concentration changes in Midwestern rivers?","docAbstract":"In many Midwestern rivers, elevated concentrations of herbicides occur during runoff events for 1-3 months following application. The highest or 'peak' herbicide concentration often occurs during one of these runoff events. Herbicide concentrations in rivers are affected by a number of factors, including herbicide use patterns within the associated basin. Changing agricultural practices, reductions in recommended and permitted herbicide applications, shifts to new herbicides, and greater environmental awareness in the agricultural community have resulted in changes to herbicide use patterns. In the Midwestern United States, alachlor use was much larger in 1989 than in 1995, while acetochlor was not used in 1989, and commonly used in 1995. Use of atrazine, cyanazine, and metolachlor was about the same in 1989 and 1995. Herbicide concentrations were measured in samples from 53 Midwestern rivers during the first major runoff event that occurred after herbicide application (postapplication) in 1989, 1990, 1994, and 1995. The median concentrations of atrazine, alachlor, cyanazine, metribuzin, metolachlor, propazine, and simazine all were significantly higher in 1989/90 than in 1994/95. The median acetochlor concentration was higher in 1995 than in 1994. Estimated daily yields for all herbicides and degradation products measured, with the exception of acetochlor, were higher in 1989/90 than in 1994/95. The differences in concentration and yield do not always parallel changes in herbicide use, suggesting that other changes in herbicide or crop management are affecting concentrations in Midwestern rivers during runoff events.In many Midwestern rivers, elevated concentrations of herbicides occur during runoff events for 1-3 months following application. The highest or `peak' herbicide concentration often occurs during one of these runoff events. Herbicide concentrations in rivers are affected by a number of factors, including herbicide use patterns within the associated basin. Changing agricultural practices, reductions in recommended and permitted herbicide applications, shifts to new herbicides, and greater environmental awareness in the agricultural community have resulted in changes to herbicide use patterns. In the Midwestern United States, alachlor use was much larger in 1989 than in 1995, while acetochlor was not used in 1989, and commonly used in 1995. Use of atrazine, cyanazine, and metolachlor was about the same in 1989 and 1995. Herbicide concentrations were measured in samples from 53 Midwestern rivers during the first major runoff event that occurred after herbicide application (postapplication) in 1989, 1990, 1994, and 1995. The median concentrations of atrazine, alachlor, cyanazine, metribuzin, metolachlor, propazine, and simazine all were significantly higher in 1989/90 than in 1994/95. The median acetochlor concentration was higher in 1995 than in 1994. Estimated daily yields for all herbicides and degradation products measured, with the exception of acetochlor, were higher in 1989/90 than in 1994/95. The differences in concentration and yield do not always parallel changes in herbicide use, suggesting that other changes in herbicide or crop management are affecting concentrations in Midwestern rivers during runoff events.","language":"English","publisher":"ACS","doi":"10.1021/es9900149","issn":"0013936X","usgsCitation":"Battaglin, W., and Goolsby, D.A., 1999, Are shifts in herbicide use reflected in concentration changes in Midwestern rivers?: Environmental Science & Technology, v. 33, no. 17, p. 2917-2925, https://doi.org/10.1021/es9900149.","productDescription":"9 p.","startPage":"2917","endPage":"2925","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":229067,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":206187,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1021/es9900149"}],"volume":"33","issue":"17","noUsgsAuthors":false,"publicationDate":"1999-07-27","publicationStatus":"PW","scienceBaseUri":"5059ed5fe4b0c8380cd49786","contributors":{"authors":[{"text":"Battaglin, W.A.","contributorId":16376,"corporation":false,"usgs":true,"family":"Battaglin","given":"W.A.","email":"","affiliations":[],"preferred":false,"id":390183,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Goolsby, D. A.","contributorId":50508,"corporation":false,"usgs":true,"family":"Goolsby","given":"D.","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":390184,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70021341,"text":"70021341 - 1999 - Effects of winter burning and structural marsh management on vegetation and winter bird abundance in the Gulf Coast Chenier Plain, USA","interactions":[],"lastModifiedDate":"2012-03-12T17:19:50","indexId":"70021341","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3750,"text":"Wetlands","onlineIssn":"1943-6246","printIssn":"0277-5212","active":true,"publicationSubtype":{"id":10}},"title":"Effects of winter burning and structural marsh management on vegetation and winter bird abundance in the Gulf Coast Chenier Plain, USA","docAbstract":"Marshes in the Gulf Coast Chenier Plain provide important winter habitats for many species of birds. Many of these marshes are managed intensively through a combination of fall/winter burning and construction of impoundments to improve wintering waterfowl habitat, reduce wetland loss, and create emergent wetlands. Little information is available on effects of this management on wintering birds, particularly passerines. We conducted experimental burns in impounded and unimpounded marshes on Rockefeller State Wildlife Refuge in southwest Louisiana and recorded species composition and abundance of birds during the 1996 and 1997 winters. We found that burning and impoundment influenced vegetation structure, which in turn influenced bird abundance and species composition. Blackbirds (Icteridae) preferred recently burned plots. Sparrows (Emberizidae) and wrens (Troglodytidae) avoided recently burned plots but recolonized these plots after one year of vegetation recovery. Sparrows and wrens present in burned plots during the first winter following burning generally were observed in scattered patches of unburned vegetation. Suitability of Chenier Plain marshes as winter habitat for several bird species was reduced during the winter in which burning was conducted, particularly if a high proportion of the plot was burned. We recommend that patchy burns be used, at both the landscape level and within specific burned areas, to achieve management objectives and still provide suitable winter habitat for non-target species. Although many groups of birds depend on Chenier Plain marshes for winter habitat, these groups differ in their specific habitat requirements. We recommend that a diverse wetland complex (e.g., impoundments managed for waterfowl foraging habitat interpersed with those managed for passerine winter cover) be maintained.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Wetlands","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","issn":"02775212","usgsCitation":"Gabrey, S., Afton, A., and Wilson, B., 1999, Effects of winter burning and structural marsh management on vegetation and winter bird abundance in the Gulf Coast Chenier Plain, USA: Wetlands, v. 19, no. 3, p. 594-606.","startPage":"594","endPage":"606","numberOfPages":"13","costCenters":[],"links":[{"id":230227,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"19","issue":"3","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a0848e4b0c8380cd51a66","contributors":{"authors":[{"text":"Gabrey, S.W.","contributorId":68062,"corporation":false,"usgs":true,"family":"Gabrey","given":"S.W.","email":"","affiliations":[],"preferred":false,"id":389531,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Afton, A. D.","contributorId":83467,"corporation":false,"usgs":true,"family":"Afton","given":"A. D.","affiliations":[],"preferred":false,"id":389532,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Wilson, B.C.","contributorId":103026,"corporation":false,"usgs":true,"family":"Wilson","given":"B.C.","email":"","affiliations":[],"preferred":false,"id":389533,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70021411,"text":"70021411 - 1999 - The relative importance of light and nutrient limitation of phytoplankton growth: A simple index of coastal ecosystem sensitivity to nutrient enrichment","interactions":[],"lastModifiedDate":"2018-12-19T08:40:31","indexId":"70021411","displayToPublicDate":"1999-01-01T00:00:00","publicationYear":"1999","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":863,"text":"Aquatic Ecology","active":true,"publicationSubtype":{"id":10}},"title":"The relative importance of light and nutrient limitation of phytoplankton growth: A simple index of coastal ecosystem sensitivity to nutrient enrichment","docAbstract":"Anthropogenic nutrient enrichment of the coastal zone is now a well-established fact. However, there is still uncertainty about the mechanisms through which nutrient enrichment can disrupt biological communities and ecosystem processes in the coastal zone. For example, while some estuaries exhibit classic symptoms of acute eutrophication, including enhanced production of algal biomass, other nutrient-rich estuaries maintain low algal biomass and primary production. This implies that large differences exist among coastal ecosystems in the rates and patterns of nutrient assimilation and cycling. Part of this variability comes from differences among ecosystems in the other resource that can limit algal growth and production - the light energy required for photosynthesis. Complete understanding of the eutrophication process requires consideration of the interacting effects of light and nutrients, including the role of light availability as a regulator of the expression of eutrophication. A simple index of the relative strength of light and nutrient limitation of algal growth can be derived from models that describe growth rate as a function of these resources. This index can then be used as one diagnostic to classify the sensitivity of coastal ecosystems to the harmful effects of eutrophication. Here I illustrate the application of this diagnostic with light and nutrient measurements made in three California estuaries and two Dutch estuaries.
","language":"English","publisher":"Kluwer Academic Publishers","doi":"10.1023/A:1009952125558","issn":"13862588","usgsCitation":"Cloern, J., 1999, The relative importance of light and nutrient limitation of phytoplankton growth: A simple index of coastal ecosystem sensitivity to nutrient enrichment: Aquatic Ecology, v. 33, no. 1, p. 3-16, https://doi.org/10.1023/A:1009952125558.","productDescription":"14 p. ","startPage":"3","endPage":"16","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":552,"text":"San Francisco Bay-Delta","active":false,"usgs":true},{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true},{"id":5079,"text":"Pacific Regional Director's Office","active":true,"usgs":true}],"links":[{"id":230074,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":206514,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1023/A:1009952125558"}],"volume":"33","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505baf2ce4b08c986b3245da","contributors":{"authors":[{"text":"Cloern, J. E.","contributorId":59453,"corporation":false,"usgs":true,"family":"Cloern","given":"J. E.","affiliations":[],"preferred":false,"id":389785,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ]}