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Effects Of Wastewater Discharges On Periphyton Growth In Lake Mead, Nevada-Arizona, Marsha Korb Morris

Publications (WR)

A study of the effects of secondary-treated wastewater on periphyton growth in Lake Mead, Nevada-Arizona was conducted from September 1979 to December 1980. Periphyton ash-free dry weight, chlorophyll-a, dominant species composition, and alkaline phosphatase activity were measured on fiberglass substrates. Substrates were incubated for two to four weeks in littoral and limnetic habitats. Physical and chemical variables and phytoplankton chlorophyll-a were measured concurrently.

Transparency increased with increasing distance from the discharge. Secchi depth ranged from 0.75 m at the discharge confluence (station 2) in August, to greater than 20 m at the most distant stations (stations 9 and 10) in …

Toxic Organic Compounds In Surface Sediments From Elizabeth And Patapsco Rivers And Estuaries, Rudolph H. Bieri, Chris Hein, Robert J. Huggett, Philip Shou, Harold Slone, Craig Smith, Chih-Wu Su

Reports

This study is an extension of a Chespeake Bay-wide analysis of toxic organic substances into the Elizabeth and Patapsco River subestuaries. Twenty-eight surface sediment samples from the.Elizabeth River and 40 surface sediment samples from the Patapsco, were analyzed in detail for the presence of mainly aromatic and polar organic compounds. Approximately 310 distinct compounds were identified by gas chromatography-mass spectrometry in the Elizabeth River samples, and about 480 in the Patapsco. Total aromatic concentrations ranged from 440,000 to 3,100 ppb in the Elizabeth and from 2.7 x 106 to 6100 ppb in the Patapsco. Similar to observation in the.Chesapeake Bay, …

An Ecological Analysis Of Relic Diatoms In Sediments Of Las Vegas Bay, Lake Mead, David Ross Hetzel

Publications (WR)

Relic diatoms in sediments of the inner Las Vegas Bay, near the Las Vegas Wash sewage inflow, were examined in order to assess historic trophic conditions in this area of Lake Mead. Diatom sedimentation rates and ratios of Araphidineae/Centrales (A/C) diatom groups were determined from sediment cores collected in the old wash channel 1.5 km from the sewage inflow (station 2), in a small cove 1.5 km further downstream (station 3) and in an adjacent embayment off Gypsum Wash (station 4). Diatom sedimentation rates generally increased from the bottom to the top of each core, but pronounced minima existed at …

Development, Verification And Use Of Methods To Model Chemical And Thermal Processes For Lakes Mead And Powell, John Eric Edinger, Edward M. Buchak, Joseph S. Norton, Bureau Of Reclamation

Publications (WR)

Analysis and development of carbonate-bicarbonate chemical subroutine.

Primary Production In Tampa Bay, Florida: A Review, J.O. R. Johansson

Reports

Primary production data for Tampa Bay is very limited. The phytoplankton component has received the greatest study effort; however, even knowledge of this group is limited and biased by the lack of area-wide and long-term studies, and the use of questionable methodologies. This review will summarize historical primary production data; discuss methodologies and their shortcomings; outline future research needs for understanding the carbon cycle of the Tampa Bay system; and discuss the carbon cycle in relation to trophic dynamics.

Land Use Inventory Of Salt Lake County, Utah From Color Infrared Aerial Photography 1982, Kevin P. Price, Reynold D. Willie, Douglas J. Wheeler, Merrill K. Ridd

All U.S. Government Documents (Utah Regional Depository)

Salt lake County, Utah's major population center, continues to experience rapid urban growth. The Impacts of urbanization on land use patterns and natural resources in the county are of particular Interest to both state and local policy makers and planners. The effect of urban development on a dwindling agricultural land base and water resources must be assessed to allow a rational basis for future water allocation and land use planning .

Flood Insurance Study, Federal Emergency Management Agency

All U.S. Government Documents (Utah Regional Depository)

This Flood Insurance Study investigates the existence and severity of flood hazards in the City of Logan, Cache County, Utah, and aids in the administration of the National Flood Insurance Act of 1968 and the Flood Disaster Protection Act of 1973. This study will be used to convert Logan to the regular program of flood insurance by the Federal Emergency Management Agency (FEMA). Local and regional planners will use this study in their efforts to promote sound flood plain management.

The Effects Of Atrazine On Zostera Marina In The Chesapeake Bay, Virginia, Carl H. Hershner, Keith B. Ward, Jerome E. Illowsky, Et Al

Reports

This project was designed to assess the effects of agricultural herbicides on submerged aquatic vegetation in the lower Chesapeake Bay. Atrazine was selected for testing because it is the most widely utilized herbicide in the Bay region. Zostera marina was the submerged vegetation studied.

The project began with two surveys. The first survey, conducted in 1979, covered forty eight stations throughout the Virginia portion of the Chesapeake Bay. The survey was designed to indicate typical atrazine loading for the lower Bay. A second survey in 1980 was limited to the Severn River, and was intended to indicate the duration of …