Knowledge Core Collection:https://hdl.handle.net/11681/468442024-03-28T10:43:00Z2024-03-28T10:43:00ZRECOVERY : a mathematical model to predict the temporal response of surface water to contaminated sedimentsBoyer, Jean M.Chapra, Steven C.Ruiz, Carlos E.Dortch, Mark S.https://hdl.handle.net/11681/43842024-03-27T15:00:02Z1994-11-01T00:00:00ZTitle: RECOVERY : a mathematical model to predict the temporal response of surface water to contaminated sediments
Authors: Boyer, Jean M.; Chapra, Steven C.; Ruiz, Carlos E.; Dortch, Mark S.
Description: Technical Report; Abstract: RECOVERY is a PC-based screening-level model to assess the impact of contaminated bottom sediments on surface waters. The analysis is limited to organic contaminants with the assumption that the water column is well mixed. The contaminant is assumed to follow linear, reversible, equilibrium sorption and first-order decay kinetics. The physical representation of a system by RECOVERY consists of a well-mixed water column (i.e., zero-dimensional) underlain by a vertically stratified sediment column (i.e., one-dimensional). The sediment is well mixed horizontally, but segmented vertically into a well-mixed surface (active) layer and deep sediment The deep sediment is segmented into contaminated and clean sediment regions. Pathways incorporated in the RECOVERY model, in addition to sorption and decay, are volatilization, burial, resuspension, settling, advection, and pore-water diffusion. RECOVERY is designed for interactive implementation via a personal computer. The program allows the user to rapidly generate and analyze recovery scenarios for contaminated sediments. The software includes graphical displays and is self-documented. A description of the model, a confirmation application, and a user's guide are included in this report.1994-11-01T00:00:00ZWater quality management for reservoirs and tailwaters. Report 1, In-reservoir water quality management techniquesCooke, G. Dennis (George Dennis), 1937-Kennedy, Robert H.https://hdl.handle.net/11681/43832023-04-06T18:21:25Z1989-01-01T00:00:00ZTitle: Water quality management for reservoirs and tailwaters. Report 1, In-reservoir water quality management techniques
Authors: Cooke, G. Dennis (George Dennis), 1937-; Kennedy, Robert H.
Description: Technical Report; Abstract: Reservoirs are a valuable national resource and provide flood control, water supply, and hydroelectrical, navigational, recreational, and aesthetic benefits. Human influences threaten the quality of this resource, and appropriate protection and enhancement methods must be developed. Of particular concern are the consequences of eutrophication, the process by which lakes and reservoirs are enriched with sediment, organic matter, and plant nutrients. Elevated nutrient concentrations, rooted plant infestations, reduced transparency, excessive algal growth, reduced dissolved oxygen concentrations in bottom waters, and elevated concentrations of organics in finished drinking water are symptoms of this process. Available in-reservoir methods for the management of these eutrophication-related problems are reported here. Also described are methods for problem diagnosis and the selection of appropriate methods. The manual is intended for water quality managers with a variety of scientific and engineering backgrounds. Detailed reference sections provide sources of additional information for each method.
NOTE: This file is large. Allow your browser several minutes to download the file.1989-01-01T00:00:00ZDirect and indirect influences of aquatic macrophyte communities on phosphorus mobilization from littoral sediments of an inlet region in Lake Delavan, WisconsinJames, William F., Aquatic biologistSmith, Craig S., BiologistBarko, John W.Field, Stephenhttps://hdl.handle.net/11681/43812024-03-12T20:36:03Z1995-09-01T00:00:00ZTitle: Direct and indirect influences of aquatic macrophyte communities on phosphorus mobilization from littoral sediments of an inlet region in Lake Delavan, Wisconsin
Authors: James, William F., Aquatic biologist; Smith, Craig S., Biologist; Barko, John W.; Field, Stephen
Description: Technical Report; Abstract: Direct and indirect influences of aquatic macrophytes on phosphorus (P) mobilization from littoral sediments of the inlet region of Lake Delavan, Wisconsin, were examined. Macrophyte species composition, biomass, and P content were evaluated at the approximate peak in biomass to estimate the macrophyte P pool. Submersed macrophytes occupied over 50 percent of the inlet surface area and contained about 600 kg of P, most of which was derived presumably from the inlet sediments via root uptake. Rates of P release from sediments of the inlet region were examined in the laboratory under different redox and pH regimes using sediment systems and also in situ using sediment peepers. In the laboratory, rates of P release from sediments increased about twofold (i.e., to 7 mg m⁻² d⁻¹) under oxic conditions as a result of adjusting the pH of the overlying water from 8.5 to about 9.0. Laboratory rates increased to a maximum of 23 mg m⁻² d⁻¹ under anoxic conditions. Both pH and dissolved oxygen (DO) in the inlet region exhibited marked seasonal fluctuations, as a result of community metabolism. Using continuous records of pH and DO in the inlet region and ranges in rates of P release measured in the laboratory, an overall mean rate of P release of 5.7 mg m⁻² d⁻¹ from the littoral sediments was estimated during the summer (April-September) of 1994. Rates of P release estimated from Fickean diffusional fluxes were similar to rates estimated from pH and DO. Results suggest that the aquatic macrophyte community of the inlet region of Lake Delavan plays an important role in the P budget of this system.1995-09-01T00:00:00ZWind-induced sediment resuspension and export in Marsh Lake, Western MinnesotaJames, William F., Aquatic biologistBarko, John W.https://hdl.handle.net/11681/43822024-03-27T18:53:28Z1995-08-01T00:00:00ZTitle: Wind-induced sediment resuspension and export in Marsh Lake, Western Minnesota
Authors: James, William F., Aquatic biologist; Barko, John W.
Description: Technical Report; Abstract: Budgetary information and sediment resuspension dynamics were determined in Marsh Lake, located on the Minnesota River in western Minnesota. Resuspension and discharge of seston, particulate organic matter (POM), and total phosphorus (total P) were examined in Marsh Lake during June through September 1991 and May through September 1992. Based on a theoretical wave model, lakebed sediments at water sampling stations in Marsh Lake were susceptible to sediment resuspension at wind velocities as low as 10.5 km/h, depending on wind direction. Mean daily wind speeds were > 10 km/h on over 40 percent of the days during both study years, suggesting a strong potential for frequent sediment resuspension at these stations. Measured resuspension of seston, POM, and total P was much lower in Marsh Lake in 1991 than in 1992 as an apparent result of dense aquatic macrophyte beds that in 1991 covered nearly the entire lake. In 1992, when aquatic vegetation was absent from Marsh Lake, seston, POM, and total P concentrations increased substantially in the water column as a result of sediment resuspension. The discharge of high concentrations of resuspended sediment and associated constituents from Marsh Lake occurred primarily when strong winds were blowing from the northwest toward the outlet weir of Marsh Lake. The critical wind velocity for the discharge of resuspended seston, POM, and total P was 20 km/h in 1991, when aquatic plants were present, and only 12 km/h in 1992, when aquatic plants were absent. Thus, discharge of resuspended sediment occurred only 2 percent of the time in 1991 and 15 percent of the time in 1992. The results of these studies were used to critically evaluate management alternatives for habitat and water quality improvements in Marsh Lake.1995-08-01T00:00:00Z