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Presentation Abstracts
Title: Patterns in Water Quality Imparted to the Seneca River from Zebra Mussel Invasion
Authors:
Clifford A. Siegfried
Biological Survey of the New York State Museum, Albany, NY 12230
Steven W. Effler, Carol M. Matthews (Brooks), MaryGail Perkins,
Upstate Freshwater Institute
P.O. Box 506
Syracuse, NY 13214
James M. Hassett
SUNY-ESF
Syracuse, New York, 13210
Abstract:The conspicuous shifts in summertime values of common measures of water quality that have persisted for seven years (1993 – 1999) in the Seneca River, NY, as a result of the zebra mussel invasion are documented. Resolution of patterns in time and space is supported by water quality monitoring that extended from the 1970s through 1999. Dense zebra mussel populations (e.g., > 20,000 individuals m-2) have been maintained in certain river sections with rock substrate since the invasion, though substantial variations have occurred. The water quality signatures imparted to this river have been particularly strong. Changes in summer average conditions since the invasion include: 1) > 8-fold decrease in chlorophyll concentrations, 2) > 2-fold increase in Secchi disc transparency, 3) 10-fold increase in soluble reactive phosphorus (SRP) concentration, 4) 4-fold increase in ammonia concentration, 5) 20% decrease in dissolved oxygen concentration, and 6) decrease in pH of 0.7 units. The strength of these signatures has been driven by anthropogenic influences, including upstream nutrient loading and morphometric modifications of the river, and the functioning of Cross Lake, through which the river flows. This hypereutrophic lake sustains dense zebra mussel populations and related water quality impacts in the river downstream of the lake outflow by acting as a source of veligers and suitable food for this bivalve. The decreases in phytoplankton biomass in the river downstream of the lake are demonstrated to be consistent with grazing of the resident zebra mussel population.
Title: Water Quality Modeling for Seneca River that Accommodates Zebra Mussel Metabolism.
1. ZOD in the 'Cut'
Authors:
Rakesh K. Gelda, Steven W. Effler,
Upstate Freshwater Institute
P.O. Box 506
Syracuse, NY 13214
Emmet M. Owens
Department of Civil and Environ. Engr.;
Syracuse Univ., Syracuse, NY 13210
Abstract: The development, testing and application of a dynamic two-dimensional (longitudinal-vertical) mass balance model for dissolved oxygen (DO) for rivers is documented that for the first time accommodates the oxygen demand associated with zebra mussels. The test system is a short (2.3 km) phytoplankton-rich section of the Seneca River, NY, that is believed to represent an upper bound of the impact of this exotic invader on oxygen resources because of the unusually high population densities and limited turbulent mixing that prevail. Model testing is supported by comprehensive measurements of DO, that resolve diurnal and seasonal patterns, and various forcing conditions over a four month period. Wide variations in the areal consumption rate of DO by zebra mussels (ZOD; g×m-2×d-1), as determined through model calibration, occurred over the study period. These determinations are supported by closure with earlier estimates based on simple DO budget calculations, and with laboratory biomass-specific oxygen consumption rates published in the scientific literature. Values of ZOD at times (e.g., >50 g×m-2 d-1) were an order of magnitude greater than the sediment oxygen demand associated with organically enriched deposits. The model performs well in simulating important features of the complex patterns of DO observed, including: (1) DO depletion across the study section, (2) vertical DO stratification, and (3) diurnal changes. ZOD was the dominant sink for DO over the study river section; it was entirely responsible for the substantial observed DO depletion, and it was the major cause of the DO stratification during periods of low flow. A preliminary extension of the model is demonstrated to be successful in simulating the persistence of DO depletion 15 km downstream. The model is expected to have management utility for this and other phytoplankton-rich rivers that have been, or will be, invaded by zebra mussels.
Title: Water Quality Modeling for Seneca River that Accommodates Zebra Mussel Metabolism. 2. Chlorophll and DO from the 'Cut' to Baldwinsville
Authors:
Rakesh K. Gelda, Steven W. Effler
Upstate Freshwater Institute,
P.O. Box 506
Syracuse, NY. 13214
Abstract:The development, testing and application of a dynamic two-dimensional (longitudinal-vertical) mass balance model for dissolved oxygen (DO) and chlorophyll (Chl) for rivers is documented that for the first time accommodates both the oxygen demand and filtering effects of zebra mussels. The test system is a phytoplankton-rich section (~ 15 km long) of the Seneca River, NY, that is believed to represent an upper bound of the impact of this exotic invader. Changes in common measures of water quality of the river brought about by the zebra mussel invasion are reviewed and related longitudinal patterns in DO, Chl, and Secchi disc transparency are documented. Model testing is supported by comprehensive measurements of DO, Chl, and various forcing conditions over a three month period, and independent determinations of several model coefficients. Wide variations in the areal consumption rate of DO (ZOD; g·m-2·d-1) and filtering rate (m3·m-2·d-1) of zebra mussels, as determined through model calibration, occurred over the study period. Values of ZOD in areas with dense zebra mussel populations at times (e.g., > 50 g·m-2 d-1) were an order of magnitude greater than the sediment oxygen demand associated with organically enriched deposits. The value of determinations of these fluxes from model calibration procedures is evaluated within the context of the limitations of protocols presently available to support independent specification of these rates. Model analyses are conducted to evaluate the relative magnitude of source and sink processes for DO and Chl, the potential operation and implications of feedback from low DO levels on oxygen consumption by zebra mussels, and the sensitivity of model simulations to selected sources of uncertainty and variability. Model projections of oxygen resources of the river are presented in a probabilistic format in evaluating reductions in zebra mussel biomass that would be necessary to eliminate violations of standards and regain assimilative capacity.
Title:A Hydrodynamic Model of the Onondaga Lake - Seneca River System
Authors:
Emmet M. Owens
Department of Civil and Environmental Engineering
Syracuse University
Abstract:Due to the elevated salinity of Onondaga Lake relative to the Seneca River, stratified flow occurs in the river channels near the confluence of these two water flows when streamflows are low. A predictive hydrodynamic model for this system is presented. Two submodels are used, a two-layer submodel for stratified flow, and a one-layer submodel for unstratified conditions. Each submodel is based on conservation equations for water volume and momentum applied to each layer. Stratified flow occurs in three distinctly different regions in the vicinity of this confluence. In the channel of the Seneca River upstream of the confluence, a "salt wedge" exists, with relatively salty lake water intruding upstream from the confluence along the channel bottom. In the lake outlet channel which connects the lake itself to the confluence, a "surface wedge" of relatively buoyant river water intrudes upstream from the confluence at the surface, with the intrusion sometimes extending upstream into the lake itself. In the two-layer description of these stratified conditions, appropriate entrainment relationships are used to describe interaction of the layers. In the third stratified region, river and lake water move downstream from the confluence, with vertical mixing steadily reducing stratification. Several empirical coefficients in the model are calibrated based on observations made in 1991; model verification utilized data from 1982, when lake salinity was significantly higher. The model is then used to investigate the influence of factors affecting stratified flow, including lake salinity, dam operations, and wastewater discharges.
Title: Amphibian Distributions Within the Onondaga Lake Ecosystem: Field and Laboratory Investigations.
Authors:
Peter K. Ducey, John Sternfeld, Kevin A. Douglass, and Jesse Smith
Department of Biological Sciences
SUNY Cortland
Cortland, NY 13045
Abstract: Although amphibians are integral parts of functioning wetland ecosystems, little is known about the effects of habitat disturbances and restoration efforts on herpetofaunal populations. We are using long-term field studies and laboratory experimentation to investigate amphibian distributions in Onondaga Lake and its adjacent wetlands. Our field studies involve a full spectrum of sampling techniques monitoring all life history stages. To complement the field data, we are directly assessing the toxicity of water from the lake and wetlands on developing amphibian embryos. We use Xenopus laevis for most of our embryology work (the ASTM FETAX procedure), although embryos from native frogs have also been tested. The field studies indicate that amphibians currently do not breed or spend substantial time within Onondaga Lake or its connected wetlands. However, they do live and breed within wetlands adjacent to, but not connected with, the lake. We found that water from connected wetlands and the lake has variable, but consistently negative, effects on amphibian development relative to controls.
Title: Oxygen Dynamics in Onondaga Lake
Authors:
Charles T. Driscoll
Department of Civil and Environmental Engineering Syracuse University
Syracuse, NY 13244
Steven W. Effler and Susan M. Doerr O'Donnell
Upstate Freshwater Institute
P.O. Box 506,
Syracuse, NY 13214
Abstract: Oxygen is a critical resource in aquatic ecosystems. Onondaga Lake has experienced chronic depletion of oxygen in the hypolimnion during summer and throughout the water column during fall turnover. Introduction of organic matter into the hypolimnion not only results in the depletion of oxygen, but also the reduction of sulfate and carbon, to sulfide and methane, respectively. In addition, ammonia is released to the water column from mineralization of organic matter. These reduced solutes are oxidized during fall turnover, facilitating the marked depletion of oxygen during this period.
To better understand the factors controlling oxygen dynamics, we conducted material and electron budgets for the hypolimnion of Onondaga Lake during 1989-91. These data indicate that deposition and oxidation of organic matter to the hypolimnion first results in the reduction of oxygen followed by nitrate, iron, and sulfate reduction and methanogenesis. Of these processes, oxygen and sulfate reduction and methanogenesis were the most important pathways for the mineralization of organic matter. A parallel analysis of carbon budgets indicate that only 75% of the organic carbon deposited to the hypolimnion was oxidized to carbon dioxide or fermented to methane. The balance of the organic matter is retained in sediments.
Title: Seasonal Variation in the Rate of Phosphorus Release from the Sediments of Onondaga Lake
Authors:
Michael R. Penn
Department of Civil and Environmental Engineering, University of Wisconsin-Platteville
Platteville, WI 53818
Abstract: Phosphorus (P) release rates were measured on intact sediment cores collected from the major depositional basin of Onondaga Lake. Release experiments were conducted under a matrix of redox and pH conditions to investigate the importance of calcium- and iron-related physicochemistry on sediment cores collected seasonally, i.e. during spring, summer, fall and winter periods. Strong seasonal variation in P release was observed with rates ranging from approximately 3 to 38 mgP@m‑2@d‑1. This variation is attributed to changes in redox status and P concentration gradients at the sediment‑water interface. An oxidized microlayer at the sediment‑water interface partially inhibits sediment P release under isothermal, well mixed conditions in the spring and fall. Phosphorus trapped in the oxic microlayer (sorption) is freed when the microlayer is chemically reduced at the onset of anoxia and high P release rates are observed. The oxidized microlayer serves to regulate seasonality in rates of sediment P release, but does not influence long term sediment-water exchange. It is proposed that the long term P release process is best represented by a time-weighted annual average rate, calculated here to be approximately 10 mgP@m‑2@d‑1. Implications for lake management will be discussed.
Title: Sediment Nitrogen Diagenesis and the Recovery of Onondaga Lake
Authors:
Martin T. Auer
Department of Civil & Environmental Engineering
Michigan Technological University
Trent R. Wickman
Minnesota Pollution Control Agency
Duluth, Minnesota
Abstract: A mass balance model was developed to predict a lake's annual average sediment ammonia release rate as a function of the labile nitrogen content of the sediment. Model coefficients were derived by applying diagenesis theory to the analysis of total nitrogen (TN) profiles in the sediment. Steady state (constant PON deposition) and non-steady state (time variable PON deposition) cases, accommodating kinetic frameworks with multiple PON fractions were examined. Model predictions were verified by 3 independent estimates of the release rate.
The modeling approach was applied to Onondaga Lake, NY, a hypereutrophic urban system with a 100-year history of industrial and municipal pollution. PON deposition, as characterized by sediment TN profiles, varied dramatically over the past 50 years, with peak deposition in the 1970s. Nitrogen diagenesis and recycle was best simulated using a 2G (i.e. fast and slow labile N) non-steady state approach. The diagenesis coefficients were estimated to be 4.4 and 0.14 yr-1, for the fast and slow fractions, respectively. At deposition, 50% of the PON is in the fast fraction, 30% is in the slow fraction, and 20% is refractory. The present day sediment ammonia release rate predicted by the model was 76 ± 11 mgN×m-2×yr-1, a value which compared well with rates derived from intact sediment core incubations (78 ± 16 mgN×m-2×yr-1), porewater profiles (58 ± 12 mgN×m-2×yr-1), and observations of hypolimnetic ammonia accumulation (91 ± 21 mgN×m-2×yr-1). It is estimated, based on values for the diagenesis coefficients, that the sediment response time to changes in rates of PON deposition in Onondaga Lake is approximately 20 years.
Title: Onondaga Lake's Responses to Early Stages of Rehabilitation for Domestic Waste Pollution
Authors:
David A. Matthews, Steven W. Effler, Carol M. Matthews (Brooks), Mike Spada
Upstate Freshwater Institute
P.O. Box 506
Syracuse, NY 13214
Clifford A. Siegfried
Biological Survey of the New York State Museum, Albany, NY 12230
Abstract: Responses of polluted Onondaga Lake, NY, to early stages of a phased program to rehabilitate the lake for the effects of domestic waste inputs are documented. The analysis is based on more than 10 years of paired monitoring of the effluent [ammonia (T-NH3) and total phosphorus (TP)] of a wastewater treatment plant (WWTP) that discharges to the lake and the lake itself [including T-NH3, nitrite (NO2-), TP and dissolved forms of P, plankton biomass and composition, Secchi disc transparency, and zebra mussel density]. Major reductions in T-NH3 and TP loading relative to the preceding decade are reported for the WWTP for the November 1998 through October 1999 interval. Dramatic changes in the lake's water quality and biota, in response to the reductions in loading, are documented for the April – October interval of 1999, including: (1) major decreases in T-NH3 concentrations and improved status with respect to ammonia toxicity standards, (2) development of dense populations of zebra mussels, (3) decreases in fall concentrations of NO2- and improved status with respect to the related toxicity standard, (4) decreases in TP and total dissolved P concentrations, and (5) a severe Microcystis (phytoplankton) bloom that caused nuisance conditions and poor clarity. The zebra mussel invasion is attributed to the reductions in T-NH3 concentrations to below toxic levels. The Microcystis bloom was probably an indirect result of zebra mussel grazing. Additional reductions in P loading from the WWTP will be required to limit phytoplankton production and avoid the potential for continued nuisance conditions. Potential complications in resolving lake responses to future reductions in loading associated with the zebra mussel invasion are considered.
Title: Allied's Impact on Phytoplankton Deposition and Production
Authors:
Steven W. Effler, Carol M. Matthews (Brooks), and Susan M. Doerr O'Donnell
Upstate Freshwater Institute
P.O. Box 506
Syracuse, New York 13214
Charles T. Driscoll
Department of Civil and Environmental Engineering, Syracuse University
Syracuse, New York 13210
Abstract: Systematic reductions in the deposition rate of organic C, N, P and chlorophyll (Chl) are documented for Ca2+ polluted, culturally eutrophic, Onondaga Lake, NY, based on analyses of weekly sediment trap collections over the May – October interval for ten years of the 1980 – 1992 period. Inputs of both nutrient-rich domestic waste and industrial ionic waste (including Ca2+) decreased over this period. Constituent ratios of the collected sediment indicate phytoplankton biomass was the dominant source of the deposited organic C, N, and Chl. Substantial decreases in downward fluxes of these constituents occurred starting in 1987; 37, 42, 25, and 54%, on average, for organic C, N, P, and Chl, respectively. These reductions were driven primarily by the decreases in the lake's salinity and Ca2+ concentration, that resulted from the closure of a soda ash manufacturing facility (1986), rather than decreases in water column P concentrations during the study. Three different mechanisms for the decreased deposition, related to the reductions in salinity and Ca2+ concentration, are considered: (i) decrease in coating of phytoplankton with CaCO3 precipitate, (ii) increased grazing of phytoplankton by large cladocerans, and (iii) decreases in coagulation of phytoplankton. The greater loss of phytoplankton biomass through deposition, driven by ionic waste inputs, exacerbated the lake's problem of high primary production. This response is consistent with ecological theory for nutrient saturated phytoplankton growth, but has not previously been demonstrated on a whole-lake basis.
Title: Public Education through the Onondaga Lake EMPACT Program
Authors:
Edward M. Michalenko
Onondaga Lake Cleanup Corp
Syracuse, NY
Steven W. Effler
Upstate Freshwater Institute
P.O. Box 506
Syracuse, NY 13214
Richard L. List
Syracuse City School District
Syracuse, NY
David M. O'Donnell
Innovative Engineering & Technology
Syracuse, NY
Paul B. Hai
SUNY ESF
Syracuse, NY
Abstract: A group of organizations in Syracuse, New York, lead by the Syracuse City School District (SCSD) and sponsored by the U.S. Environmental Protection Agency (EPA), formed a partnership to educate people about Onondaga Lake. Onondaga Lake is one of the most polluted bodies of water in the nation (Effler 1990, Hennigan 1990). A near one-half billion dollar remedial effort is under way to restore water quality to meet state and federal standards. Although local citizens are aware of the pollution, very few understand the lake's dynamics or cleanup issues. Consequently, the SCSD and its partners are implementing a program entitled Environmental Monitoring for Public Access and Community Tracking (EMPACT) (EPA 1998) to address the public's lack of knowledge about Onondaga Lake. The Onondaga Lake EMPACT Program centers around robotic water quality monitoring and internet web-based public education. Computerized buoys perform automated water quality sampling. The data are processed and posted in near real time on a web-site. The equipment will provide scientists and researchers monitoring capabilities that are currently unavailable via manual efforts. The water quality information, which is central to a wide variety of topics and issues, is being disseminated to the public through formal and non-formal educational means. The formal educational program includes the development of teacher curricula for multiple grade levels and subject areas in the SCSD. Non-formal educational components involve an array of interpretive means and media including kiosks and interpretive trail. The ultimate goal is to create an educated citizenry. One that is able to organize and assimilate complex information, formulate opinions based on fact, effectively and positively influence policy, and participate in decision-making.
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