California Water Science Center

Aquatic Ecosystems

Aquatic ecosystems information and data is neccessary for many California water management decisions including preservation of California's natural resources. The California Water Science Center conducts interdisciplinary research from aquatic species behavioral, population and community ecology, to the effects hydrologic extremes and climage change on ecosystems.  

Filter Total Items: 77
Date published: November 15, 2018
Status: Active

Dynamics of zooplankton in the Cache Slough Complex

Our purpose is to investigate what controls the distribution and abundance of fish prey within the Cache Slough Complex (CSC).

Date published: November 14, 2018
Status: Completed

Phytoplankton production and nutrient transformations in shallow water wetland habitats

The objectives of this study are to quantify and characterize (1) phytoplankton production on Liberty Island, (2) utilization and transformation of nutrients, and (3) attenuation/loss of phytoplankton as the material is transported from Liberty Iisland into Cache Slough.

Date published: November 13, 2018
Status: Active

Science Programs and Partnerships

The USGS partners with local, state, and other federal agencies through cooperative agreements for a variety of reasons. The USGS and partners jointly plan the scientific work conducted under cooperative agreements resulting in science that has broad relevance to address current water issues. Partners choose...

Date published: November 5, 2018
Status: Completed

USGS ground- and boat-based support for the NASA airSWOT mission on the Sacramento River, California

This field work on the Sacramento River will be performed at two scales: a coarse-scale sampling from Keswick Dam to the I-5 Bridge near the city of Sacramento using Hobo stage recorders at approximately 10 – 20 km spacing; and fine-scale surveys in two reaches, one from approximately 30 km upstream and downstream of Colusa and another 30 km reach downstream of Knight’s Landing using Hobo...

Contacts: Justin Minear
Date published: November 5, 2018
Status: Completed

Nitrogen Dynamics Along the Sacramento River and Links to Phytoplankton Dynamics: Resolving Spatial and Temporal Variability Using In-Situ, High-Frequency Measurements and Other Tools

The overall project objective is to further our understanding of the link between nitrogen and phytoplankton dynamics in the Sacramento River and to elucidate effects of wastewater treatment plant effluent on food web dynamics.

Contacts: Tamara Kraus
Date published: November 5, 2018
Status: Completed

Development of unimpaired flows for mountain basins draining to the Bay Delta

The objective of this study is to develop daily historical climate surfaces and simulate unimpaired basin discharge, including surface water flow and baseflow, from all basins that drain to the Bay Delta. Basin drainage will be calibrated to DWR reconstructed flows, and comparisons of results will be made with other independently developed watershed models for basins in which they coincide. A...

Date published: November 1, 2018
Status: Completed

Interactions Between Physical Processes and Suspended Sediment Quality in Relation to Spawning Migrations of Delta Smelt

The proposed study is designed to better establish relationships between patterns of delta smelt abundance and properties of suspended particles as measured by optical and acoustical techniques.

Date published: October 31, 2018
Status: Active

Causes and Relevance of Phytoplankton Blooms in the Northern Sacramento-San Joaquin Delta

Phytoplankton are an important part of aquatic food webs and ecosystems. These single-celled plants grow faster in the stronger light of spring or summer, resulting in population explosions called phytoplankton blooms. These blooms in turn feed zooplankton (free-floating aquatic microorganisms), providing food for many aquatic species, including fish, shrimp, crabs, and other invertebrates....

Date published: October 31, 2018
Status: Active

Improved Lower South Bay suspended-sediment flux measurements

Tidal marshes provide animal habitats and prevent erosion. Expanding towns and cities have claimed major parts of San Francisco Bay’s marshland. Sediment deposits are essential to rebuilding tidal marshes and keeping existing marshes intact. In the southern part of the Bay, the largest tidal wetland restoration project on the west coast is underway. Sediment flux measurements are key in...

Date published: October 24, 2018
Status: Active

Sediment supply, salt marsh monitoring, and the carbon budget of Humboldt Bay, CA

Suspended-sediment measurements are essential for coastal planning, resource management, and for assessing the sustainability of salt marshes in relation to expected sea-level rise. Suspended sediment can have positive or negative effects, depending on its characteristics and amount, and on the location and ecosystem services of interest. Sediment deposition in salt marshes helps sustain marsh...

Date published: October 18, 2018
Status: Active

Decomposition of Organic Soils in the Sacramento-San Joaquin Delta

The Sacramento-San Joaquin Delta of California was once a great tidal freshwater marsh. It is blanketed by peat and peaty alluvium deposited where streams originating in the Sierra Nevada, Coast Ranges, and South Cascade Range enter San Francisco Bay. In the late 1800s, levees were built along the stream channels, and the land thus protected from flooding was drained, cleared, and planted ('...

Date published: October 3, 2018
Status: Active

Implementing New Acoustic Monitoring Techniques in the Trinity River

Accurate river-sediment data is fundamental to planning and managing river restoration efforts on the Trinity River, and throughout the world’s waterways. The USGS has developed a “hydrophone” that enables scientists to listen to sediment particles as they move along the riverbed in order to inexpensively and reliably record near-continuous sediment-bedload-transport data. For this study,...