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Publications

Dive into our publications and explore the science from the Environmental Health Program (Toxic Substances Hydrology and Contaminant Biology).

Filter Total Items: 3787

Diagnostic modeling of trace metal partitioning in south San Francisco Bay

The two-dimensional numerical model ELAmet was used to investigate the effect of adsorption kinetics on the apparent distribution coefficients of Cu, Cd, and Zn in south San Francisco Bay, California. The numerical experiments were designed to determine whether adsorption kinetics can control the basin-scale variability of the observed partitioning and to define the conditions under which adsorpti
Authors
T. W. Wood, A. M. Baptista, J.S. Kuwabara, A.R. Flegal

Molecular and isotopic tracers used to examine sources of organic matter and its incorporation into the food webs of San Francisco Bay

Multiple indicators (Chl a, C : N ratios, [δ13C]POC, and two classes of lipid biomarker compounds- sterols and phospholipid ester-linked fatty acids) were used to evaluate spatial and temporal variations in the origin of particulate organic matter (POM) in the San Francisco Bay (SFB) estuary. Comparisons were made between the northern and southern subestuaries of SFB, as well as along the salinity
Authors
Elizabeth A. Canuel, James E. Cloern, David B. Ringelberg, James B. Guckert, Greg H. Rau

Seasonal-to-interannual fluctuations in surface temperature over the Pacific: effects of monthly winds and heat fluxes

Monthly heat fluxes and wind stresses are used to force the Oberhuber isopycnic ocean general-circulation (OPYC) model of the Pacific basin over a two-decade period from 1970 to 1988. The surface forcings are constructed from COADS marine observations via bulk formulae. Monthly anomalies of the fluxes and stresses are superimposed upon model climatological means of these variables, which were save
Authors
Daniel R. Cayan, Arthur J. Miller, Tim P. Barnett, Nicholas E. Graham, Jack N. Ritchie, Josef M. Oberhuber

Geochemical and hydrologic controls on phosphorus transport in a sewage-contaminated sand and gravel aquifer near Ashumet Pond, Cape Cod, Massachusetts

The disposal of secondarily treated sewage onto rapid infiltration sand beds at the Massachusetts Military Reservation, Cape Cod, Massachusetts, has created a sewage plume in the underlying sand and gravel aquifer; the part of the\x11sewage plume that contains dissolved phosphorus extends about 2,500 feet downgradient of the sewage-disposal beds. A part of the plume that\x11contains nearly 2 milli
Authors
D. A. Walter, B.A. Rea, K.G. Stollenwerk, Jennifer G. Savoie

Methylmercury oxidative degradation potentials in contaminated and pristine sediments of the Carson River, Nevada

Sediments from mercury-contaminated and uncontaminated reaches of the Carson River, Nevada, were assayed for sulfate reduction, methanogenesis, denitrification, and monomethylmercury (MeHg) degradation. Demethylation of [14C]MeHg was detected at all sites as indicated by the formation of 14CO2 and 14CH4. Oxidative demethylation was indicated by the formation of 14CO2 and was present at significant
Authors
R.S. Oremland, L.G. Miller, P. Dowdle, T. Connell, T. Barkay

How wet is wet? Precipitation constraints on late Quaternary climate in the southern Arabian Peninsula

It is generally recognized that the southern Arabian Peninsula has had two wet periods in the late Quaternary. To quantify ‘wet’ a 28 000 year old capillary surface associated with a paleowater-table was mapped and used as a surrogate for the water table in a ground-water model. Analysis of this model suggests 1.4 mm year−1 of recharge is necessary to support the water table at the mapped elevatio
Authors
W.W. Wood, Jeffrey L. Imes

Growth of strain SES-3 with arsenate and other diverse electron acceptors

The selenate-respiring bacterial strain SES-3 was able to use a variety of inorganic electron acceptors to sustain growth. SES-3 grew with the reduction of arsenate to arsenite, Fe(III) to Fe(II), or thiosulfate to sulfide. It also grew in medium in which elemental sulfur, Mn(IV), nitrite, trimethylamine N-oxide, or fumarate was provided as an electron acceptor. Growth on oxygen was microaerophili
Authors
A.M. Laverman, J.S. Blum, J.K. Schaefer, E. J. P. Phillips, D. R. Lovley, R.S. Oremland

Fluxes of water and solute in a coastal wetland sediment. 2. Effect of macropores on solute exchange with surface water

Chloride was highly concentrated relative to seawater in matrix porewater but was comparatively dilute in macropores. Concentration differences in pore-size classes declined with depth until indistinguishable below 10 cm. The segregated chloride distribution can be explained if recharge to the sediment occurred by downward infiltration in macropores and discharge occurred by an upward flux in matr
Authors
J. W. Harvey, W.K. Nuttle

Mercury cycling in the Allequash Creek watershed, northern Wisconsin

Although there have been recent significant gains in our understanding of mercury (Hg) cycling in aquatic environments, few studies have addressed Hg cycling on a watershed scale in particular, attention to Hg species transfer between watershed components (upland soils, groundwater, wetlands, streams, and lakes) has been lacking. This study describes spatial and temporal distributions of total Hg
Authors
D. P. Krabbenhoft, J.M. Benoit, Christopher L. Babiarz, J.P. Hurley, A.W. Andren