Modeling Transport in Aquatic Systems

EPA Grant Number: R825433C056
Subproject: this is subproject number 056 , established and managed by the Center Director under grant R825433
(EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).

Center: EERC - Center for Ecological Health Research (Cal Davis)
Center Director: Rolston, Dennis E.
Title: Modeling Transport in Aquatic Systems
Investigators: Mount, Jeff
Institution: University of California - Davis
EPA Project Officer: Packard, Benjamin H
Project Period: October 1, 1996 through September 30, 2000
RFA: Exploratory Environmental Research Centers (1992) RFA Text |  Recipients Lists
Research Category: Center for Ecological Health Research , Targeted Research


This project seeks to combine hydrological, geochemical and environmental magnetic methods to document provenance of particles and to track particles during transport and deposition; develop mixing models for identification of sediment sources and influences of changing land use practices on particle composition and volume; and use results to improve understanding of inputs of sediment and other water quality constituents from upper watersheds into river systems.


The investigators have been able to shift the emphasis toward an empirical assessment of some of the major unknowns in the current model, including developing a better understanding of the causes and geographic distribution of runoff and non-point inputs, particularly sediment from upper watersheds into the larger rivers and estuary best treated by the current model. They have begun by expanding the sediment transport measurements and modeling started in the Clear Lake project. In particular, a detailed sediment source sampling program is currently underway within the Sacramento basin, with an emphasis on sampling within the Clear Lake/Cache Creek Watershed. The sampling involves surface grab samples and short cores within Clear Lake, and bedload and suspended load samples within the Cache Creek Watershed and its tributaries.

Using cluster analysis, they are attempting to classify source materials into specific categories that are dependent upon their geochemistry and mineralogy. Mass-balance equations, which can be solved simultaneously through weighted linear least squares, are being developed in order to establish and calibrate a mixing model for source areas of sediment.

In addition to the geochemical analyses, the magnetic properties of bulk samples are currently being analyzed in order to identify a broad range of sources of ferromagnetic minerals, including parent rock, pedogenic minerals and authigenic minerals. Time-series analysis of magnetic and geochemical properties of sediments in Clear Lake cores have allowed us to identify temporal changes in relative contributions of source areas due to anthropogenic changes.

In conjunction with their geochemical and magnetic analyses of sediments, they are developing a GIS-based distributional data base for the Clear Lake Basin. This data base includes sample localities, and vegetation, land use, soils, geology, rainfall/runoff coverages, and DEMs. These coverages, coupled with digital terrane analyses, are currently being integrated with the geochemical/magnetic properties and time-series analyses in order to identify the role of changing land uses in changing sediment source areas.

Expected Results:

Next year the investigators will expand the particle tracking into an analysis of provenance within the entire Sacramento River Watershed and to assist on-going sediment source area studies currently being conducted within the Lake Tahoe basin.

The analysis of sediment sources is tightly coupled with a number of other CEHR projects. It will define more accurate loads and timelines of sediment and mercury inputs into the Bay-Delta projects and time series analyses. It will also refine the analysis of both upstream sources and downstream fate of sediment in the Clear Lake basin itself. Investigators also plan to use spatial data from the GIS studies to look for geological, climatological, and land cover attributes associated with high non-point source loads. The information from these analyses will aid the outreach activities assisting EPA Region IX and the state and regional water boards in evaluating TMDL issues, assessing and managing risks associated with sedimentation and non-point inputs, at the watershed level.

Supplemental Keywords:

Aquatic ecosystem, data integration, geochemical modeling, fate and transport, magnetic analysis, GIS, California, training and outreach, computer science, transport modeling., RFA, Scientific Discipline, INTERNATIONAL COOPERATION, Water, ECOSYSTEMS, Ecosystem Protection/Environmental Exposure & Risk, Aquatic Ecosystems & Estuarine Research, Water & Watershed, Aquatic Ecosystem, Fate & Transport, Monitoring/Modeling, Environmental Microbiology, Biochemistry, Terrestrial Ecosystems, Ecology and Ecosystems, Aquatic Ecosystem Restoration, Watersheds, aquatic, fate and transport, water circulation, ecosystem assessment, watershed management, ambient particle properties, sediment transport, restoration strategies, modeling, Clear Lake, chemical kinetics, watershed influences, hydrology, wetland restoration, integrated watershed model, material transport, groundwater contamination, aquatic ecosystems, environmental stress, source load modeling, watershed sustainablility, ecological models, transport modeling, ecosystem stress, ecology assessment models, ecological impact, watershed restoration, contaminant transport models

Progress and Final Reports:

  • 1997
  • 1998
  • 1999 Progress Report
  • Final Report

  • Main Center Abstract and Reports:

    R825433    EERC - Center for Ecological Health Research (Cal Davis)

    Subprojects under this Center: (EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
    R825433C001 Potential for Long-Term Degradation of Wetland Water Quality Due to Natural Discharge of Polluted Groundwater
    R825433C002 Sacramento River Watershed
    R825433C003 Endocrine Disruption in Fish and Birds
    R825433C004 Biomarkers of Exposure and Deleterious Effect: A Laboratory and Field Investigation
    R825433C005 Fish Developmental Toxicity/Recruitment
    R825433C006 Resolving Multiple Stressors by Biochemical Indicator Patterns and their Linkages to Adverse Effects on Benthic Invertebrate Patterns
    R825433C007 Environmental Chemistry of Bioavailability in Sediments and Water Column
    R825433C008 Reproduction of Birds and mammals in a terrestrial-aquatic interface
    R825433C009 Modeling Ecosystems Under Combined Stress
    R825433C010 Mercury Uptake by Fish
    R825433C011 Clear Lake Watershed
    R825433C012 The Role of Fishes as Transporters of Mercury
    R825433C013 Wetlands Restoration
    R825433C014 Wildlife Bioaccumulation and Effects
    R825433C015 Microbiology of Mercury Methylation in Sediments
    R825433C016 Hg and Fe Biogeochemistry
    R825433C017 Water Motions and Material Transport
    R825433C018 Economic Impacts of Multiple Stresses
    R825433C019 The History of Anthropogenic Effects
    R825433C020 Wetland Restoration
    R825433C021 Sierra Nevada Watershed Project
    R825433C022 Regional Transport of Air Pollutants and Exposure of Sierra Nevada Forests to Ozone
    R825433C023 Biomarkers of Ozone Damage to Sierra Nevada Vegetation
    R825433C024 Effects of Air Pollution on Water Quality: Emission of MTBE and Other Pollutants From Motorized Watercraft
    R825433C025 Regional Movement of Toxics
    R825433C026 Effect of Photochemical Reactions in Fog Drops and Aerosol Particles on the Fate of Atmospheric Chemicals in the Central Valley
    R825433C027 Source Load Modeling for Sediment in Mountainous Watersheds
    R825433C028 Stress of Increased Sediment Loading on Lake and Stream Function
    R825433C029 Watershed Response to Natural and Anthropogenic Stress: Lake Tahoe Nutrient Budget
    R825433C030 Mercury Distribution and Cycling in Sierra Nevada Waterbodies
    R825433C031 Pre-contact Forest Structure
    R825433C032 Identification and distribution of pest complexes in relation to late seral/old growth forest structure in the Lake Tahoe watershed
    R825433C033 Subalpine Marsh Plant Communities as Early Indicators of Ecosystem Stress
    R825433C034 Regional Hydrogeology and Contaminant Transport in a Sierra Nevada Ecosystem
    R825433C035 Border Rivers Watershed
    R825433C036 Toxicity Studies
    R825433C037 Watershed Assessment
    R825433C038 Microbiological Processes in Sediments
    R825433C039 Analytical and Biomarkers Core
    R825433C040 Organic Analysis
    R825433C041 Inorganic Analysis
    R825433C042 Immunoassay and Serum Markers
    R825433C043 Sensitive Biomarkers to Detect Biochemical Changes Indicating Multiple Stresses Including Chemically Induced Stresses
    R825433C044 Molecular, Cellular and Animal Biomarkers of Exposure and Effect
    R825433C045 Microbial Community Assays
    R825433C046 Cumulative and Integrative Biochemical Indicators
    R825433C047 Mercury and Iron Biogeochemistry
    R825433C048 Transport and Fate Core
    R825433C049 Role of Hydrogeologic Processes in Alpine Ecosystem Health
    R825433C050 Regional Hydrologic Modeling With Emphasis on Watershed-Scale Environmental Stresses
    R825433C051 Development of Pollutant Fate and Transport Models for Use in Terrestrial Ecosystem Exposure Assessment
    R825433C052 Pesticide Transport in Subsurface and Surface Water Systems
    R825433C053 Currents in Clear Lake
    R825433C054 Data Integration and Decision Support Core
    R825433C055 Spatial Patterns and Biodiversity
    R825433C056 Modeling Transport in Aquatic Systems
    R825433C057 Spatial and Temporal Trends in Water Quality
    R825433C058 Time Series Analysis and Modeling Ecological Risk
    R825433C059 WWW/Outreach
    R825433C060 Economic Effects of Multiple Stresses
    R825433C061 Effects of Nutrients on Algal Growth
    R825433C062 Nutrient Loading
    R825433C063 Subalpine Wetlands as Early Indicators of Ecosystem Stress
    R825433C064 Chlorinated Hydrocarbons
    R825433C065 Sierra Ozone Studies
    R825433C066 Assessment of Multiple Stresses on Soil Microbial Communities
    R825433C067 Terrestrial - Agriculture
    R825433C069 Molecular Epidemiology Core
    R825433C070 Serum Markers of Environmental Stress
    R825433C071 Development of Sensitive Biomarkers Based on Chemically Induced Changes in Expressions of Oncogenes
    R825433C072 Molecular Monitoring of Microbial Populations
    R825433C073 Aquatic - Rivers and Estuaries
    R825433C074 Border Rivers - Toxicity Studies