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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: 4047

Meromixis in hypersaline Mono Lake, California. 3. Biogeochemical response to stratification and overturn

Mono Lake is a terminal, saline lake that became ectogenically meromictic in 1982–1983 and remained stratified until November 1988. During this period, the monimolimnion remained anoxic and nearly isothermal, while the upper mixolimnion was well oxygenated and exhibited a seasonal thermal regime. Dissolved sulfide and methane increased in the monimolimnion as a result of diffusive flux from the se
Authors
Laurence G. Miller, R. Jellison, Ronald S. Oremland, Charles W. Culbertson

Isolation and chemical characterization of dissolved and colloidal organic matter

Commonly used techniques for the concentration and isolation of organic matter from water, such as preparative chromatography, ultrafiltration and reverse osmosis, and the methods used to analyze the organic matter obtained by these methods are reviewed. The development of methods to obtain organic matter that is associated with fractions of the dissolved organic carbon other than humic substances
Authors
G. Aiken, J. Leenheer

Sorption of N2 and EGME vapors on some soils, clays, and mineral oxides and determination of sample surface areas by use of sorption data

Vapor sorption isotherms of ethylene glycol monoethyl ether (EGME) at room temperature and isotherms of N2 gas at liquid nitrogen temperature were determined for various soils and minerals. The N2 monolayer capacities [Qm (N2)] were calculated from the BET equation and used to determine the surface areas. To examine whether EGME is an appropriate adsorbate for determination of surface areas, the a
Authors
C. T. Chiou, D.W. Rutherford, M. Manes

Atrazine degradation in a small stream in Iowa

A study was conducted during 1990 through an 11.2-km reach of Roberts Creek in northeastern Iowa to determine the fate of atrazine in a surface water environment Water samples were collected at ~1-month intervals from April through November during stable low to medium flow conditions and analyzed for atrazine and two of its initial biotic degradation products, desethylatrazine and deisopropylatraz
Authors
D.W. Kolpin, S. J. Kalkhoff

Development of a model of phytoplankton blooms in Manukau Harbour

No abstract available.
Authors
Graham B. McBride, W. N. Vant, J. E. Cloern, J. B. Liley

Organic carbon sources and sinks in San Francisco Bay: variability induced by river flow

Sources and sinks of organic carbon for San Francisco Bay (California, USA) were estimated for 1980. Sources for the southern reach were dominated by phytoplankton and benthic microalgal production. River loading of organic matter was an additional important factor in the northern reach. Tidal marsh export and point sources played a secondary role. Autochthonous production in San Francisco Bay ap
Authors
Alan D. Jassby, T.M. Powell, James E. Cloern

Coupled effects of vertical mixing and benthic grazing on phytoplankton populations in shallow, turbid estuaries

Coastal ocean waters tend to have very different patterns of phytoplankton biomass variability from the open ocean, and the connections between physical variability and phytoplankton bloom dynamics are less well established for these shallow systems. Predictions of biological responses to physical variability in these environments is inherently difficult because the recurrent seasonal patterns of
Authors
Jeffrey R. Koseff, Jacqueline K. Holen, Stephen G. Monismith, James E. Cloern

Spring climate and salinity in the San Francisco Bay Estuary

Salinity in the San Francisco Bay Estuary almost always experiences its yearly maximum during late summer, but climate variability produces marked interannual variations. The atmospheric circulation pattern impacts the estuary primarily through variations of runoff from rainfall and snowmelt from the Sierra Nevada and, secondarily, through variations in the near-surface salinity in the coastal oce
Authors
Daniel R. Cayan, David H. Peterson

Occurrence and transport of agricultural chemicals in the Mississippi River basin, July through August 1993

Heavy rainfall and severe flooding in the upper Mississippi River Basin from mid-June through early August 1993 flushed extraordinarily large amounts of agricultural chemicals (herbicides and nitrate) into the Mississippi River, many of its tributaries, and, ultimately, the Gulf of Mexico. Even though extremely high streamflows were recorded during the flood in 1993, concentrations of herbicides,
Authors
Donald A. Goolsby, William A. Battaglin, E. Michael Thurman