Grantee Research Project Results
2000 Progress Report: Sierra Nevada Watershed Project
EPA Grant Number: R825433C021Subproject: this is subproject number 021 , 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: UC Davis Center for Children's Environmental Health and Disease Prevention
Center Director: Van de Water, Judith
Title: Sierra Nevada Watershed Project
Investigators: Goldman, Charles R. , Rejmankova, Eliska , Carroll, John , Jassby, Alan D. , Reuter, John E. , Kavvas, M. Levant , Higashi, Richard M. , Fan, Teresa W-M. , Anastasio, Cort , Rizzo, David , Matsumura, Fumio , Fogg, Graham , Barbour, Michael
Institution: University of California - Davis
EPA Project Officer: Packard, Benjamin H
Project Period: October 1, 1996 through September 30, 2000
Project Period Covered by this Report: October 1, 1999 through September 30, 2000
RFA: Exploratory Environmental Research Centers (1992) RFA Text | Recipients Lists
Research Category: Center for Ecological Health Research , Targeted Research
Objective:
The main goal of this project is to promote the realization that to sustain and improve ecological health resource managers require state-of-the art and integrative science-based knowledge. While scientific research has been active in the Sierra Nevada for many years, it has typically been driven by the narrowly focused research interests of single investigators and has never been effectively integrated at the regional or watershed level. The notable exception to this is the UCD-Tahoe Research Group whose researchers are involved in this Center project. With the understanding that beneficial uses of aquatic environments are inexorably linked to activities in their surrounding watershed and airshed, changes in land-use, hydrology, air quality, sediment and nutrient loading, biodiversity and urbanization exert a profound influence on ecological health. Our concept of watershed research focuses on defining these linkages for the purpose of sound and prudent watershed management.
Progress Summary:
The Sierra Nevada mountain range (Figure C-1) is one of California's most vital ecological assets providing critical extractive, environmental, and scenic resources. Within its nearly 30,000 square miles, are competing demands for hydroelectric development, water supply, biodiversity, and the recreational pressure of over 50 million visitors per year. Ecological stress within the Lake Tahoe Basin reflects that found throughout most of the 400-mile range of the Sierra Nevada. In this regard, the Tahoe Basin serves as a particularly effective and convenient model for linking scientific understanding, policy and management within the context of Sierra Nevada watersheds. The health and long-term sustainability of the Tahoe Basin are influenced by a unique set of these stresses with the lake acting as the final integrator or end point (Figure C-2).
Figure C-1. Map of the Sierra Nevada Watershed, a cross-section of the Sierra Nevada from the Central Valley to Lake Tahoe. This map was produced by the Data Integration and Decision Support Core using ARC/INFO GRID modeling software.
Figure C-2. Nevada Watershed, Multiple Stresses and Ecosystem Processes
The "Sierra Summit" in 1991--a state and federally supported effort to move beyond the adversarial approach and launch a consensus building processes for improving the management of natural resources in the Sierra Nevada--helped galvanize legislative, agency and public support for a more visionary approach to the multiple problems that exist within this bioregion. Terms such as "multiple stresses", "economic sustainability", "watershed management", "environmental protection", and "ecosystem restoration" were all considered.
A long list of environmental stresses are impacting the Sierra Nevada (Figure C-2). Air quality has deteriorated during the past 40 years. The prevailing west to east winds transport a wide range of pollutants such as ozone, nitrogen, varied organic compounds, pesticides and perhaps even mercury from the urban and agricultural regions of California with serious consequence. For example, research conducted by the Tahoe Research Group through the Center has determined that atmospheric deposition of nitrogen into Lake Tahoe has resulted in a major shift in the Lake's response to nutrients. Similarly, studies supported by the Center have demonstrated that organochlorine pesticides found in Lake Tahoe fish are most likely transported by regional air currents from the agricultural Central Valley. Studies by the watershed group in conjunction with the Transport & Fate Core will help to better define the movement of airborne pollutants. Combinations of natural and anthropogenic stresses have had serious repercussions on forest health on the western slopes of the Sierra Nevada in general, and the Lake Tahoe Basin in particular. Current U.S. Forest Services estimates are that between 20-40% of all trees in the Tahoe Basin are either dead or dying. This has resulted from such factors as age of the stand, prolonged drought, and insect infestation. Other stresses on the watershed include the application of road salt, ozone injury and historical logging practices that interact to affect forest health.
Gold and sand/gravel mining resulted in massive sedimentation problems. Acidic mine drainage and heavy metal contamination have contributed to habitat loss. Indeed, the legacy of the California Gold Rush still lives in the form of a mercury body burden in fish and other aquatic biota in certain Sierra Nevada stream and foothill reservoirs following the transport of nearly 3,500 tons of quicksilver to this region for use in gold processing. Livestock grazing continues to result in loss of riparian and fisheries habitat and degradation of water quality. The Sierra Nevada is experiencing an overall loss of important biological and genetic diversity from these multiple stress factors. Since pollutants are transported downstream along with hydrologic flow, the aquatic receiving bodies often reflect the cumulative nature of these multiple stresses. Habitat loss, especially the critical wetlands which act as transitional buffers between the terrestrial and aquatic environments, proceeds without adequate replacement or restoration.
Much of the western region in the United States is either directly or indirectly dependent on high elevation ecosystems for their water supply, lumber, tourism and recreation. Therefore, the results of our research in the Sierra Nevada have great potential for direct transferability to other regions.
The formalized interdisciplinary research made possible through the Center has expanded into an integrative and applied approach to research and monitoring. The Sierra Nevada ozone study has highlighted the importance of long-range transport of atmospheric pollutants and the subsequent effects to Sierra Nevada forests as a result of exposure. These data made important contributions to both the Sierra Nevada Ecosystem Project and the U.S. Forest Service project FOREST (Forest Ozone Response Study). Ozone damage to forests is especially critical in the southern Sierra Nevada and our research to develop biomarkers which identify impacted trees, before the effects are visually obvious, provides an extremely useful tool to assess exposure. Coupled with the interactive modeling of ozone ingestion using physiological, meteorological and landscape data, this early effects ozone research provides both air quality regulators and forest managers with invaluable information.
The Tahoe Research Group (TRG) serves as a principal partner with governmental agencies in the Tahoe Basin. In 1979, the TRG developed and has continuously managed the Lake Tahoe Interagency Monitoring Program, a coordinated group of 13 federal, state and local agencies which use lake, stream and air quality data for the purpose of watershed evaluation and assessment of long-term change. Data collected to date have provided key information which are cornerstones for (1) understanding ecosystem processes, (2) determining the impacts of anthropogenic stress on environmental health, (3) formulating and evaluating watershed management options, and (4) forecasting long-term consequences of policy decisions on resource sustainability. Indeed, nearly all agencies with responsibility for water quality protection depend on TRG data for regulatory and planning purposes.
This data set is the underlying basis for nearly all major policy decisions regarding water quality in the Tahoe Basin. Prominent examples of policy changes include exportation of sewage and solid waste, strict control on building, installation of major erosion control projects, establishment of water quality thresholds, and control of nonpoint source pollution. The California Department of Justice frequently uses these scientific data and expertise of the group in litigation related to water quality protection. In a recent, precedent setting case, TRG data allowed the Tahoe Regional Planning Agency to successfully defend the states of California and Nevada in a $14.5 million law suit which if lost would have significantly relaxed needed controls on building and land disturbance in the Basin. Many aspects developed during the Lake Tahoe work were recently applied to assist the Paiute Indian Tribe in nearby Pyramid Lake, Nevada in developing a scientific and legally defensible set of water quality standards for water bodies on the reservations as permitted by the Clean Water Act (1987 Amendment). At the same time, a state and federal effort used the data and expertise of Center scientists to reclaim part of the Upper Truckee Marsh (one of the largest wetlands in the Sierra Nevada which was partially lost to development in the 1960's) and re-channelize the river into a more natural geomorphology.
The major components of the proposed research focus on processes which operate at the larger community, landscape ecosystem, and regional scales. Our approach incorporates a wide range of techniques and methodologies such as: biomarkers, direct analyses of chemical pollutants, bioaccumulation of toxic substance, quantification of environmental forcing factors, biological surveys, assessment of watershed/ecosystem impacts ('ecomarkers'), historical reconstruction using paleolimnology and tree-ring cores, geographic information systems and remote sensing, and process-oriented simulation modeling. Table 1 summarizes the integrative nature of the research. The research projects fall under three major headings (1) Atmospheric Pollutants, (2) Watershed Process, and (3) Transitional Landscapes. These areas are linked by hydrologic and atmospheric transport processes.
C.1 Atmospheric Pollutants
The goal of these projects is to document transport, exposure and impacts of
air pollutants on terrestrial and aquatic components within the Sierra Nevada
watershed. Building on previous and ongoing studies we have estimated ozone
exposure of trees and other vegetation using ground-based measurements. An H:G
lignin biomarker approach refined by Center investigators is being used to further
study the impacts of ozone on Sierra Nevada vegetation. This biochemical approach
will be used to reconstruct historical conditions by analysis of tissue formed
and subject to stress at earlier times. Using synoptic surveys, deposition modeling,
stable isotope ratios, direct collection of air samples and statistical analysis
of long-term data, we expect to determine the sources of nitrogen and phosphorus
to Sierra Nevada lakes. Finally, we will investigate regional movement of toxics
in the atmosphere by analyzing mercury and organochlorines in lake sediments.
C.2 Watershed Process
The goal of these projects is to improve our understanding of source, transport
and fate of sediment, nutrient and heavy metal pollutants in Sierra Nevada watersheds.
For reasons discussed above, much of this work (with the exception of mercury
dynamics) will be focused in the Lake Tahoe Basin. Using a combination of engineering
and ecological principles we will apply a newly developed non-point source transport
model (developed by Center investigators) at the watershed level to simulate/predict
sediment and phosphorus movement from naturally and anthropogenically disturbed
land. The results of this work, coupled with related research will help guide
watershed managers to select the erosion control and restoration projects with
the maximum cost-benefit ratio. Using state-of-the-art direct measurements and
statistical analyses of long-term time series data, we propose to determine
the response of Lake Tahoe photic environment to sediment/nutrient loading.
This provides us with the initial components for a larger watershed scale simulation
model. The effect of previous major stresses in the Lake Tahoe Basin, and ecosystem
response, are being studied using paleolimnological techniques to reconstruct
historical response of both the lake and watershed to stresses such as fire,
drought/flood, urbanization, lumber harvest practices, etc. Finally, we are
studying the mercury dynamics in Sierra Nevada aquatic systems by linking Hg-bioavailability
to chemical speciation and food chain transfers, investigating the role of large
foothill reservoirs in Hg transformations, and evaluating use of benthic invertebrate
Hg-content as a biomarker for exposure. This is being linked with the Clear
Lake Watershed research to seek commonality, if any, among mercury impacted
watersheds.
C.3 Transitional Landscapes
The goal of these projects is to study response of subalpine wetland communities
to natural and anthropogenic stress and determine their role in buffering the
effects of terrestrial stress on aquatic resources. Much of this research focuses
on defining the interrelationship between hydrologic stress and wetland health.
Few hydrologists actually work on groundwater movement in wetlands and fewer
still have combined these studies with ecological research on community structure
and function. Our first task is to determine the most important environmental
forcing factors regulating structure and function of subalpine marsh plant communities.
We will continue to monitor features of physiological stress and changes in
species biodiversity using advanced satellite remote sensing techniques. If
successful, this approach would allow for more frequent and extensive assessment
surveys. In collaboration with project limnologists and water quality scientists
we investigate both the influence of sediment and nutrient loading on wetland
communities, and the effect of wetlands on transport of these materials from
the watershed. All of these investigations will further our understanding of
the role of hydrologic processes (recharge, discharge, chemical transport) in
wetland health.
The work at Lake Tahoe is among the most mature of the long-term environmental research and monitoring sites in the nation. In this regard, it serves not only as the focal point for the Sierra Nevada Watershed research but it also plays a unique role with the Center. Given the wealth of focused research and monitoring data available for Lake Tahoe and its watershed, it provides an ideal opportunity to achieve the central goal of the Center, "to understand how multiple stresses affect biological and ecological processes in aquatic and terrestrial systems." Although the study of multiple stress at the ecosystem level is challenging, with the diversity of knowledge we now have regarding the affect of individual stresses on the Lake Tahoe watershed, with our detailed knowledge of lake and watershed processes, and with historical monitoring data documenting ecosystem response to multiple stress, the Lake Tahoe Basin provides an ideal platform from which to look at the more complex issues of multiple stresses on which the Center focuses.
Table 1. Multi-disciplinary techniques and methodologies used for investigating
Sierra Nevada watersheds.
Biomarkers
· Biomarkers of Ozone Damage to Sierra Nevada Vegetation [C.1b]
· Regional Movement of Toxics [C.1d]
· Historical Reconstruction of Watershed Response to Natural and Anthropogenic
Stress [C.2c]
· Mercury Bioavailability in Sierra Nevada Waterbodies [C2.d]
Direct Analysis of Chemical Pollutants
· Atmospheric Transport and Deposition of Pollutants and Nutrients Including
Nitrogen and Phosphorus [C1.c]
· Regional Movement of Toxics [C.1d]
· Source Load Modeling for Sediment in Mountainous Watersheds [C.2a]
· Paleolimnological Reconstruction of Sediment Deposition History [C.2c]
· Stress of Increased Sediment Loading on Lake and Stream Function [C.2b]
· Mercury Bioavailability in Sierra Nevada Waterbodies [C2.d]
· Subalpine Wetlands as Early Indicators of Ecosystem Stress [C.3a]
Bioaccumulation of Toxic Substances
· Regional Movement of Toxics [C.1d]
· Mercury Bioavailability in Sierra Nevada Waterbodies [C2.d]
Quantification of Environmental Forcing Factors
· Transport of Air Pollutants and Exposure of Forests to Ozone [C.1a]
· Source Load Modeling for Sediment in Mountainous Watersheds [C.2a]
· Paleolimnological Reconstruction of Sediment Deposition History [C.2c]
· Subalpine Wetlands as Early Indicators of Ecosystem Stress [C.3a]
· The Role of Hydrogeologic Processes in Wetland Health [C.3b]
Biological Surveys
· Biomarkers of Ozone Damage to Sierra Nevada Vegetation [C.1b]
· Mercury Bioavailability in Sierra Nevada Waterbodies [C2.d]
· Subalpine Wetlands as Early Indicators of Ecosystem Stress [C.3a]
· Stress of Increased Sediment Loading on Lake and Stream Function [C.2b]
· Pest Complexes as Mortality Factors of Forest Trees (C.2f)
Watershed/Ecosystem Impacts
· Atmospheric Transport and Deposition of Nitrogen and Phosphorus [C1.c]
· Source Load Modeling for Sediment in Mountainous Watersheds [C.2a]
· Paleolimnological Reconstruction of Sediment Deposition History [C.2c]
· Stress of Increased Sediment Loading on Lake and Stream Function [C.2b]
· Subalpine Wetlands as Early Indicators of Ecosystem Stress [C3.a]
Historical Reconstruction
· Biomarkers of Ozone Damage to Sierra Nevada Vegetation [C.1b]
· Paleolimnological Reconstruction of Sediment Deposition History [C.2c]
Geographic Information Systems - Remote Sensing
· Source Load Modeling for Sediment in Mountainous Watersheds [C.2a]
· Subalpine Wetlands as Early Indicators of Ecosystem Stress [C3.a]
Process Oriented Simulation Modeling
· Transport of Air Pollutants and Exposure of Forests to Ozone [C.1a]
· Source Load Modeling for Sediment in Mountainous Watersheds [C.2a]
Supplemental Keywords:
RFA, Scientific Discipline, INTERNATIONAL COOPERATION, Water, ECOSYSTEMS, Ecosystem Protection/Environmental Exposure & Risk, Water & Watershed, Aquatic Ecosystems & Estuarine Research, Restoration, Aquatic Ecosystem, Environmental Microbiology, Terrestrial Ecosystems, Biochemistry, Environmental Monitoring, Aquatic Ecosystem Restoration, Watersheds, anthropogenic stress, contaminant exposure, biodiversity, watershed management, fish habitat, mercury, nutrients, marine biogeochemistry, restoration strategies, hydrology, wetland restoration, integrated watershed model, aquatic ecosystems, environmental stress, watershed sustainablility, Sierra Nevada, ecosystem stress, ecology assessment models, ecological impact, aquatic habitat protection , land use, ecological researchProgress and Final Reports:
Original AbstractMain Center Abstract and Reports:
R825433 UC Davis Center for Children's Environmental Health and Disease Prevention 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
The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.