A5088494142- Coastal wetland ecosystem dynamics
- Coastal and Marine Dynamics
- Geological formations and processes
- Water Quality and Resources Studies
- Oceanographic and Atmospheric Processes
- Hydrology and Sediment Transport Processes
- Hydrology and Watershed Management Studies
- Fish Ecology and Management Studies
- Marine and fisheries research
- Soil erosion and sediment transport
- Marine and coastal ecosystems
- Water Quality Monitoring Technologies
- Soil and Water Nutrient Dynamics
- Mercury impact and mitigation studies
- Isotope Analysis in Ecology
- Underwater Acoustics Research
- Hydraulic flow and structures
- Tropical and Extratropical Cyclones Research
- Geology and Paleoclimatology Research
- Marine and coastal plant biology
- Aeolian processes and effects
- Water Quality Monitoring and Analysis
- Heavy metals in environment
- Atmospheric and Environmental Gas Dynamics
- Soil Geostatistics and Mapping
United States Geological Survey
2009-2021
California Water Science Center
2009-2020
California Science Center
2010-2019
University of California, Davis
1985-2015
United States Army Corps of Engineers
2009
Mississippi State University
2006
Virginia Aquarium & Marine Science Center
2006
Exponent (United States)
2006
San Francisco Estuary Institute
2004
Watershed
2004
Background Accumulating evidence shows that the planet is warming as a response to human emissions of greenhouse gases. Strategies adaptation climate change will require quantitative projections how altered regional patterns temperature, precipitation and sea level could cascade provoke local impacts such modified water supplies, increasing risks coastal flooding, growing challenges sustainability native species. Methodology/Principal Findings We linked series models investigate responses...
Geophysical time series often contain missing data, which prevents analysis with many signal processing and multivariate tools. A modification of singular spectrum for data is developed successfully tested synthetic actual incomplete suspended‐sediment concentration from San Francisco Bay. This method also can be used to low pass filter series.
Human activities within a watershed, such as agriculture, urbanization, and dam building, may affect the sediment yield from watershed. Because equilibrium geomorphic form of an estuary is dependent in part on supply anthropogenic watershed have potential to geomorphology. The Sacramento River drains northern half California's Central Valley primary source San Francisco Bay. In this paper, it shown that delivery suspended-sediment Bay has decreased by about one-half during period 1957 2001....
Studying the dynamics and geochemical behavior of dissolved particulate organic material is difficult because concentration composition may rapidly change in response to aperiodic as well periodic physical biological forcing. Here we describe a method useful for quantifying fluxes analyzing matter (DOM) dynamics. The uses coupled optical acoustic measurements that provide robust quantitative estimates concentrations constituent characteristics needed investigate processes calculate DOM tidal...
Submerged aquatic vegetation (SAV) has well-documented effects on water clarity. SAV beds can slow movement and reduce bed shear stress, promoting sedimentation reducing suspension. However, estuaries have multiple controls turbidity that make it difficult to determine the effect of In this study, we investigated primarily invasive expansion a concomitant decline in Sacramento-San Joaquin River Delta. The objective study was separate decreasing sediment supply from watershed increasing cover...
Measurements of suspended‐solids concentration (SSC) were made at two depths three sites in South San Francisco Bay (South Bay) to determine the factors that affect SSC. Twenty‐eight segments reliable and continuous SSC time series data longer than 14 days collected from late 1991 or 1992 through September 1993. Spectral analysis singular spectrum used relate these several potential forcing factors, including diurnal semidiurnal tides, spring‐neap tidal cycle, wind shear, freshwater runoff,...
Abstract Vertical gradational structures develop as sand infiltrates into static gravel beds. Understanding the vertical distribution of interstitial deposits will improve predictions ecological suitability and hyporheic hydrodynamics. A series flume experiments was performed to investigate fine infiltration processes. Four distributions were introduced flows over After each experiment, bed cores extracted analysed in layers examine trends with depth. content highly sensitive relative...
Where rivers encounter estuaries, a transition zone develops where riverine and tidal processes both affect sediment transport processes. One such is the Sacramento‐San Joaquin River Delta, large, complex system several meet to form an estuary (San Francisco Bay). Herein we present results of detailed budget for this river/estuary transitional system. The primary regional goal study was measure rates pathways in delta support ecosystem restoration efforts. In addition achieving goal, has...
Future estuarine geomorphic change, in response to climate sea-level rise, and watershed sediment supply, may govern ecological function, navigation, water quality. We estimated changes Suisun Bay, CA, under four scenarios using a tidal-timescale hydrodynamic/sediment transport model. Computational expense data needs were reduced the morphological hydrograph concept acceleration factor. The included (1) present-day conditions; (2) rise freshwater flow of 2030; (3) decreased supply (4)...
Techniques for measurement, modeling, and management of fluid mud are available, but research is needed to improve them. Fluid can be difficult detect, measure, or sample, which has led new instruments ways using existing instruments. Multifrequency acoustic fathometers sense neither density nor viscosity are, therefore, unreliable in measuring mud. Nuclear probes, towed sleds, seismic, drop probes equipped with meters offer the potential accurate measurements. Numerical modeling requires...