Tracing hydrologic pathways using chloride at the Panola mountain research watershed, Georgia, USA
N.E. Peters, E.B. Ratcliffe
1998, Water, Air, & Soil Pollution (105) 263-275
An analysis of chloride (Cl-) concentrations and fluxes at the 41 ha Panola Mountain Research Watershed indicates that Cl- may be used effectively to differentiate 'new' and 'old' water flow through the hillslope and their respective contributions to streamwater. Rainfall and throughfall, the 'new' water inputs, are marked by low...
Strain IMB-1, a novel bacterium for the removal of methyl bromide in fumigated agricultural soils
Hancock T.L. Connell, A.M. Costello, M.E. Lidstrom, R.S. Oremland
1998, Applied and Environmental Microbiology (64) 2899-2905
A facultatively methylotrophic bacterium, strain IMB-1, that has been isolated from agricultural soil grows on methyl bromide (MeBr), methyl iodide, methyl chloride, and methylated amines, as well as on glucose, pyruvate, or acetate. Phylogenetic analysis of its 16S rRNA gene sequence indicates that strain IMB-1 classes in the alpha subgroup...
Impact of the 1993 flood on the distribution of organic contaminants in bed sediments of the Upper Mississippi River
L. B. Barber, J.H. Writer
1998, Environmental Science & Technology (32) 2077-2083
The 1500 km Upper Mississippi River (UMR) consists of 29 navigation pools and can be divided into the upper reach (pools 1-4), the middle reach (pools 5-13), and the lower reach (pools 14-26). Comparison of composite bed sediment samples collected from the downstream third of 24 pools before and after...
Application of the top specified boundary layer (TSBL) approximation to initial characterization of an inland aquifer mineralization 1. Direct contact between fresh and saltwater
H. Rubin, R. W. Buddemeier
1998, Journal of Contaminant Hydrology (32) 353-376
This paper presents a basic study in generalized terms that originates from two needs: (1) to understand the major mechanisms involved in the mineralization of groundwater of the Great Bend Prairie aquifer of Kansas by saltwater originating from a deeper Permian bedrock formation, and (2) to develop simple, robust tools...
Analysis of transient storage subject to unsteady flow: Diel flow variation in an Antarctic stream
R.L. Runkel, Diane M. McKnight, E.D. Andrews
1998, Journal of the North American Benthological Society (17) 143-154
Transport of dissolved material in streams and small rivers may be characterized using tracer-dilution methods and solute transport models. Recent studies have quantified stream/substream interactions using models of transient storage. These studies are based on tracer-dilution data obtained during periods of steady flow. We present...
Lithological and hydrological influences on ground-water composition in a heterogeneous carbonate-clay aquifer system
S.J. Kauffman, J.S. Herman, B.F. Jones
1998, Geological Society of America Bulletin (110) 1163-1173
The influence of clay units on ground-water composition was investigated in a heterogeneous carbonate aquifer system of Miocene age in southwest Florida, known as the Intermediate aquifer system. Regionally, the ground water is recharged inland, flows laterally and to greater depths in the...
Estimating ice-affected streamflow by extended Kalman filtering
D. J. Holtschlag, M.S. Grewal
1998, Journal of Hydrologic Engineering (3) 174-181
An extended Kalman filter was developed to automate the real-time estimation of ice-affected streamflow on the basis of routine measurements of stream stage and air temperature and on the relation between stage and streamflow during open-water (ice-free) conditions. The filter accommodates three dynamic modes of ice effects: sudden formation/ablation, stable...
Interaction between stream temperature, streamflow, and groundwater exchanges in alpine streams
James E. Constantz
1998, Water Resources Research (34) 1609-1615
Four alpine streams were monitored to continuously collect stream temperature and streamflow for periods ranging from a week to a year. In a small stream in the Colorado Rockies, diurnal variations in both stream temperature and streamflow were significantly greater in losing reaches than in gaining reaches, with minimum streamflow...
Controls on denitrification in riparian soils in headwater catchments of a hardwood forest in the Catskill Mountains, U.S.A.
J.A. Ashby, W.B. Bowden, Peter S. Murdoch
1998, Soil Biology and Biochemistry (30) 853-864
Denitrification in riparian soils is thought to be an important factor that reduces hydrologic export of nitrate from forested and agricultural catchments. A 2-y study to identify the soil factors most closely associated with denitrification in riparian soils in headwater catchments within the Catskill Mountains of New York, included field...
Comparative sequence stratigraphy of low-latitude versus high-latitude lacustrine rift basins: Seismic data examples from the East African and Baikal rifts
C.A. Scholz, T.C. Moore Jr., D. R. Hutchinson, A. Ja Golmshtok, Kim D. Klitgord, A.G. Kurotchkin
1998, Conference Paper, Palaeogeography, Palaeoclimatology, Palaeoecology
Lakes Baikal, Malawi and Tanganyika are the world's three largest rift valley lakes and are the classic modem examples of lacustrine rift basins. All the rift lakes are segmented into half-graben basins, and seismic reflection datasets reveal how this segmentation controls the filling of the rift basins through time. In...
Methyl mercury dynamics in littoral sediments of a temperate seepage lake
D. P. Krabbenhoft, C.C. Gilmour, J.M. Benoit, Christopher L. Babiarz, A.W. Andren, J.P. Hurley
1998, Canadian Journal of Fisheries and Aquatic Sciences (55) 835-844
The sites and rates of methyl mercury (MeHg) production and transport in littoral zone sediments were investigated at Pallette Lake in northern Wisconsin. In littoral areas where groundwater inflow occurs, sulfate supply from groundwater creates profiles of electron acceptors (sulfate) and donors (methane, sulfide) that are reversed from those found...
Models of metal binding structures in fulvic acid from the Suwannee River, Georgia
J.A. Leenheer, G.K. Brown, P. MacCarthy, S.E. Cabaniss
1998, Environmental Science & Technology (32) 2410-2416
Fulvic acid, isolated from the Suwannee River, Georgia, was assessed for its ability to bind Ca2+, Cd2+, Cu2+, Ni2+, and Zn2+ ions at pH 6 before and after extensive fractionation that was designed to reveal the nature of metal binding functional groups. The binding constant for Ca2+ ion had the...
Hydrologic functions of prairie wetlands
J. W. LaBaugh, T. C. Winter, D.O. Rosenberry
1998, Great Plains Research (8) 17-37
Wetlands in the prairie known as potholes or sloughs represent an ever-changing mosaic of surface waters interacting with the atmosphere, groundwater, and each other in a variety of ways. Studies of groups of adjacent wetlands in different parts of the glaciated North American prairie have enabled some connections to be...
Colloid particle sizes in the Mississippi River and some of its tributaries, from Minneapolis to below New Orleans
C.E. Rostad, T.F. Rees, S.R. Daniel
1998, Hydrological Processes (12) 25-41
An on-board technique was developed that combined discharge-weighted pumping to a high-speed continuous-flow centrifuge for isolation of the particulate-sized material with ultrafiltration for isolation of colloid-sized material. In order to address whether these processes changed the particle sizes during isolation, samples of particles in suspension were collected at various steps...
How good are estimates of transmissivity from slug tests in fractured rock?
A.M. Shapiro, P. A. Hsieh
1998, Ground Water (36) 37-48
Slug tests in fractured rock usually are interpreted with models that assume homogeneous formation properties, even though hydraulic properties of fractures can vary by many orders of magnitude over the length of boreholes. To investigate the impact of heterogeneity on the interpretation of slug tests in fractured rock, slug tests...
Simulated effects of irrigation on salinity in the Arkansas River Valley in Colorado
K. Goff, M.E. Lewis, M.A. Person, Leonard F. Konikow
1998, Ground Water (36) 76-86
Agricultural irrigation has a substantial impact on water quantity and quality in the lower Arkansas River valley of southeastern Colorado. A two-dimensional flow and solute transport model was used to evaluate the potential effects of changes in irrigation on the quantity and quality of water in the alluvial aquifer and...
Simulation of variable-density flow and transport of reactive and nonreactive solutes during a tracer test at Cape Cod, Massachusetts
Hubao Zhang, Frank W. Schwartz, Warren W. Wood, S. P. Garabedian, D.R. LeBlanc
1998, Water Resources Research (34) 67-82
A multispecies numerical code was developed to simulate flow and mass transport with kinetic adsorption in variable-density flow systems. The two-dimensional code simulated the transport of bromide (Br−), a nonreactive tracer, and lithium (Li+), a reactive tracer, in a large-scale tracer test performed in a sand-and-gravel aquifer at Cape Cod,...
AIRSLUG: A fortran program for the computation of type curves to estimate transmissivity and storativity from prematurely terminated air-pressurized slug tests
E.A. Greene, A.M. Shapiro
1998, Ground Water (36) 373-375
The Fortran code AIRSLUG can be used to generate the type curves needed to analyze the recovery data from prematurely terminated air-pressurized slug tests. These type curves, when used with a graphical software package, enable the engineer or scientist to analyze field tests to estimate transmissivity and storativity. Prematurely terminating...
Humic substances as a mediator for microbially catalyzed metal reduction
Derek R. Lovley, J.L. Fraga, E. L. Blunt-Harris, L.A. Hayes, Elizabeth J.P. Phillips, J.D. Coates
1998, Acta Hydrochimica et Hydrobiologica (26) 152-157
The potential for humic substances to serve as a terminal electron acceptor in microbial respiration and to function as an electron shuttle between Fe(III)‐reducing microorganisms and insoluble Fe(III) oxides was investigated. The Fe(III)‐reducing microorganism Geobacter metallireducens conserved energy to support growth from electron transport to humics as evidenced...
Black Mats, Spring-Fed Streams, and Late-Glacial-Age Recharge in the Southern Great Basin
Jay Quade, R. M. Forester, W.L. Pratt, C. Carter
1998, Quaternary Research (49) 129-148
Black mats are prominent features of the late Pleistocene and Holocene stratigraphic record in the southern Great Basin. Faunal, geochemical, and sedimentological evidence shows that the black mats formed in several microenvironments related to spring discharge, ranging from wet meadows to shallow ponds. Small land snails such as Gastrocopta tappaniana...
Exchanges of sediment between the flood plain and channel of the Amazon River in Brazil
T. Dunne, L.A.K. Mertes, R.H. Meade, J.E. Richey, B.R. Forsberg
1998, Geological Society of America Bulletin (110) 450-467
Sediment transport through the Brazilian sector of the Amazon River valley, a distance of 2010 km, involves exchanges between the channel and the flood plain that in each direction exceed the annual flux of sediment out...
Multivariate classification of small order watersheds in the Quabbin Reservoir Basin, Massachusetts
R.M. Lent, M.C. Waldron, J. C. Rader
1998, Journal of the American Water Resources Association (34) 439-450
ABSTRACT: A multivariate approach was used to analyze hydrologic, geologic, geographic, and water-chemistry data from small order watersheds in the Quabbin Reservoir Basin in central Massachusetts. Eighty three small order watersheds were delineated and landscape attributes defining hydrologic, geologic, and geographic features of the watersheds were...
Effects of a beaver pond on runoff processes: comparison of two headwater catchments
Douglas A. Burns, Jeffery J. McDonnell
1998, Journal of Hydrology (205) 248-264
Natural variations in concentrations of 18O, D, and H4SiO4 in two tributary catchments of Woods Lake in the west-central Adirondack Mountains of New York were measured during 1989–1991 to examine runoff processes and their implications for the neutralization of acidic precipitation by calcium carbonate treatment. The two catchments are similar except that...
Microbial mineralization of VC and DCE under different terminal electron accepting conditions
P. M. Bradley, F. H. Chapelle
1998, Anaerobe (4) 81-87
Production of 14CO2 from [1,2-14C] dichloroethene (DCE) or [1,2-14C] vinyl chloride (VC) was quantified in aquifer and stream-bed sediment microcosms to evaluate the potential for microbial mineralization as a pathway for DCE and VC biodegradation under aerobic, Fe(III)-reducing, SO4-reducing, and methanogenic conditions. Mineralization of [1,2-14C] DCE and [1,2-14C] VC to...
Salinity trends in surface waters of the Upper Colorado River Basin, Colorado
N.J. Bauch, N.E. Spahr
1998, Journal of Environmental Quality (27) 640-655
Dissolved-solids data collected in the Upper Colorado River Basin upstream from Cameo, Colorado, and in the Gunnison River Basin were analyzed for trends in flow-adjusted dissolved-solids concentrations and loads for water years 1970 to 1993, 1980 to 1993, and 1986 to 1993. Trend results for flow-adjusted...
