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  • Title

    Delta Aquatic Resource Inventory

    Lead Sacramento-San Joaquin Delta Conservancy
    Description The Delta Aquatic Resources Inventory of surface waters, wetlands and other aquatic resources in the Sacramento-San Joaquin Delta (Delta) will provide a standard regional approach to wetland classification and mapping to support wetland restoration planning, tracking, and reporting. It will faciliate implementation of the California Wetland and Riparian Areas Monitoring Plan (WRAMP) in the Delta.
    Science topics Wetland mapping
    Updated November 17, 2022
  • Title

    Delta Landscapes Project

    Lead San Francisco Estuary Institute [SFEI]
    Description The Delta Landscapes Project has developed a body of work to inform landscape-scale restoration of the Sacramento-San Joaquin Delta ecosystem. The project is built on knowledge, first published in 2012’s Delta Historical Ecology Investigation, of how the Delta ecosystem functioned in the early 1800s (prior to the California Gold Rush and subsequent landscape-level changes).
    Science topics Landscape metrics, Restoration planning, Marsh wildlife, Riparian wildlife, Terrestrial wildlife, Fish
    Updated April 29, 2022
  • Title

    Delta Landscapes Primary Production Project

    Lead San Francisco Estuary Institute [SFEI]
    Description This project compares first-order estimates of primary production among five major groups of primary producers, historically and today, to better identify the potential food production of different habitat types, and inform restoration actions that could increase food availability for wildlife.
    Science topics Primary production, Phytoplankton, Emergent macrophytes, Epiphytic algae, SAV/FAV
    Updated April 29, 2022
  • Title

    Delta Regional Monitoring Program Mercury Monitoring

    Lead Delta Regional Monitoring Program [RMP]
    Description Monitoring of sport fish and water was conducted by the Delta Regional Monitoring Program (Delta RMP) from August 2016 to April 2017 to begin to address the highest priority information needs related to implementation of the Sacramento–San Joaquin Delta Estuary Total Maximum Daily Load (TMDL) for Methylmercury (Wood et al. 2010). Two species of sport fish, largemouth bass (Micropterus salmoides) and spotted bass (Micropterus punctulatus), were collected at six sampling locations in August and September 2016. The length-adjusted (350 mm) mean methylmercury (measured as total mercury, which is a routinely used proxy for methylmercury in predator fish) concentration in bass ranged from 0.15 mg/kg or parts per million (ppm) wet weight at Little Potato Slough to 0.61 ppm at the Sacramento River at Freeport. Water samples were collected on four occasions from August 2016 through April 2017. Concentrations of methylmercury in unfiltered water ranged from 0.021 to 0.22 ng/L or parts per trillion. Concentrations of total mercury in unfiltered water ranged from 0.91 to 13 ng/L. Over 99% of the lab results for this project met the requirements of the Delta RMP Quality Assurance Program Plan, and all data were reportable. This data report presents the methods and results for the first year of monitoring. Historic data from the same or nearby monitoring stations from 1998 to 2011 are also presented to provide context. Monitoring results for both sport fish and water were generally comparable to historic observations. For the next several years, annual monitoring of sport fish will be conducted to firmly establish baseline concentrations and interannual variation in support of monitoring of long-term trends as an essential performance measure for the TMDL. Monitoring of water will solidify the linkage analysis (the quantitative relationship between methylmercury in water and methylmercury in sport fish) in the TMDL. Water monitoring will also provide data that will be useful in verifying patterns and trends predicted by numerical models of mercury transport and cycling being developed for the Delta and Yolo Bypass by the California Department of Water Resources (DWR).
    Science topics Biosentinels, Fish, Methylmercury, Restoration, Water
    Updated November 17, 2022
  • Title

    Problems and Promise of Restoring Tidal Marsh to Benefit Native Fishes in the North Delta during Drought and Flood

    Lead University of California - Davis [UC Davis]
    Description The Project will improve scientific understanding of the North Delta ecosystem and to improve better basis for management and creation of restoration sites, as well as management of the region to benefit native fishes. The Project will improve scientific understanding of how fish populations are influenced by the interactions between wetlands and hydrology, geomorphology, water quality and food availability. Funding will be use to conduct water quality monitoring;hydrodynamic modeling;and fish and invertebrate surveys.
    Science topics None specified
    Updated April 29, 2022
  • Title

    Tidal Wetland Restoration in the Bay-Delta Region: Developing Tools to Measure Carbon Sequestration, Subsidence Reversal, and Climate Resiliance 2021

    Lead California State University [CSU]
    Description Tidal marshes are important ecosystems in the San Francisco-Bay Delta. They remove carbon from the atmosphere, build up soils that buffer our communities from sea level rise, mitigate excessive nutrients (like nitrogen), and provide critical habitat and food resources for a diversity of species. It is difficult to predict how tidal marshes change naturally over time versus as a response to climate change, restoration and water quality changes. This project provides the first ever multi-year dataset of the complete carbon budget of a tidal marsh. This dataset will be used to predict seasonal and annual carbon budgets in tidal marshes over a range of salinities. The model will assess the sustainability of existing and potential restored tidal wetland benefits over the next 100 years using remote sensing data. The model will be an open-source tool designed for use by wetland managers and decision makers in the Bay-Delta region. This project supports ongoing initiatives to restore tidal wetlands in the Delta and our ability to manage them in a changing world.
    Science topics None specified
    Updated April 29, 2022
  • Title

    Wetland carbon sequestration and impacts of climate change

    Lead California State University [CSU]
    Description This project aims to improve understanding of atmospheric and hydrologic carbon fluxes in a restored tidal salt marsh in the South San Francisco Bay. I will use soil chambers to measure how much carbon dioxide and methane is taken in and emitted from the marsh. The project will also examine how spatial variability in marsh surface cover impact these exchanges. Shahan will use the data collected in this study to create a biogeochemical model that estimates the carbon budgets of wetlands in the Bay-Delta. A complete carbon budget will illuminate relationships between carbon fluxes and environmental variables. This information can support more informed management of wetlands, as well as allow researchers and decision makers to more effectively plan wetland restoration to be effective in managing carbon fluxes in the face of possible impacts due to climate change.
    Science topics Wetlands
    Updated April 29, 2022
  • Title

    Environmental Monitoring Program (EMP)

    Lead California Department of Water Resource [DWR]
    Description

    The Environmental Monitoring Program (EMP) began in 1975 to conduct baseline and compliance monitoring of water quality, phytoplankton, zooplankton, and benthic invertebrates in the San Francisco Bay-Delta estuary. This monitoring program was designed to track the impact of water diversions to the State Water Project (SWP) and Central Valley Project (CVP) on the Bay-Delta. In the decades since, EMP scientists have monitored these constituents at fixed and floating stations throughout the estuary and ensured compliance with state and federal mandates such as Water Right Decision 1641 (D-1641). In the years and decades since its inception, EMP has become one of the cornerstones for scientists' and managers' understanding of the pace and pattern of change in this critical ecosystem. By sampling water quality and biological communities concurrently, EMP has created a dataset that is uniquely useful in better understanding causal connections between physical, biological, and biogeochemical processes. 
    Science topics Algae, Ammonia, Benthic, Benthos, Bivalve, Carbon, Chemistry, Chlorophyll A / B, Climate change, Conductivity, Corbicula/Potamocorbula, Crustaceans, Cyanobacteria, Delta islands, Detritus, Dissolved oxygen, Docks and ports, Drought, Environmental drivers, Estuaries, Food webs, Harmful algal blooms HAB, Invasive / non native species, Invertebrates, Jellyfish, Main channels, Mollusks, Nitrogen, Nitrogen / ammonia, Nutrients, Open water, Other species, Other zooplankton, pH, Phosphorous, Phytoplankton, Primary production, Salinity, Sediments, Sloughs, Surface water / flow, Suspended sediment, Temperature, Tidal wetlands, Tides, Turbidity, Water, Water conveyance / infrastructure, Water management, Water operations / exports, Water temperature, Zooplankton
    Updated October 16, 2024
  • Title

    Yolo Bypass Fish Monitoring

    Lead California Department of Water Resource [DWR]
    Description California Department of Water Resources (DWR) has operated a fisheries monitoring program in the Yolo Bypass, a seasonal floodplain and tidal slough, since 1998. The objectives of the Yolo Bypass Fish Monitoring Program (YBFMP) are to: (1) collect baseline data on lower trophic levels (phytoplankton, zooplankton, and aquatic insects), juvenile fish and adult fish, hydrology, and water quality parameters;(2) investigation of the temporal and seasonal patterns in chlorophyll-a concentrations, including whether high concentrations are exported from the Bypass during agricultural and natural flow events and the possibility of manipulating bypass flows to benefit listed species like Delta Smelt (Hypomesus transpacificus) and Chinook salmon (Oncorhynchus tshawytscha). The YBFMP operates a rotary screw trap and fyke trap, and conducts biweekly beach seine and lower trophic surveys in addition to maintaining water quality instrumentation in the bypass. The YBFMP serves to fill information gaps regarding environmental conditions in the bypass that trigger migrations and enhanced survival and growth of native fishes, as well as provide data for IEP synthesis efforts.
    Science topics Chinook Salmon, Chlorophyll A / B, Conductivity, Delta Smelt, Direction, Dissolved oxygen, Endangered species, Fish, Flood, Food webs, Green sturgeon, Habitat, Habitat restoration, Insects, Intertidal / transition zones, Invasive / non native species, Invertebrates, Longfin Smelt, Main channels, Nitrogen, Nitrogen / ammonia, Nutrients, Other species, Other zooplankton, Pelagic fish, pH, Phytoplankton, Primary production, Sacramento Splittail, Salmon migration, Salmon rearing, Saltwater / freshwater marshes, SAV/FAV, Seasonally flooded, Solar irradiance, Stage, Steelhead Trout, Striped bass, Sturgeon, Submerged aquatic vegetation, Surface water / flow, Tides, Turbidity, Velocity, Water, Water temperature, Wetlands, White Sturgeon, Zooplankton
    Updated August 28, 2024
  • Title

    Using high frequency flux measurements to constrain dissolved inorganic carbon in a tidal wetland carbon budget

    Lead California State University - East Bay
    Description The main purpose of this project is to determine how much carbon (C) is annually sequestered and exported laterally in a tidal wetland environment through the calculation of a net ecosystem C budget. C hydrologic export, mainly in the form of dissolved inorganic C (DIC), is poorly constrained and can pose a significant component of a wetland C budget that is often overlooked. This project intends to reduce that uncertainty by providing a better understanding of the biogeochemical drivers of C cycling and give further insight into wetland management decision-making.
    Science topics Carbon, Restoration, Tidal wetlands
    Updated November 30, 2022
  • Title

    Restoring tidal marsh foodwebs: assessing restoration effects on trophic interactions and energy flows in the San Francisco Bay-Delta

    Lead University of California - Berkeley [UC Berkeley]
    Description The objective of this research on tidal marsh food webs is to examine whether and how restoration (via breaching dikes) may translate into recovery of diverse energy pathways and trophic interactions between basal resources, primary consumers, and predators. By comparing food webs at several tidal marshes, I will answer the following questions: (1) How does food web structure vary between reference and restored tidal marshes over time (seasons and years) and across a salinity gradient? (2)What mechanisms explain variation in food web structure within and between reference and restored tidal marshes–are they related to energy flows (food quantity, quality, transfer efficiency), community composition, or both? (3) What role do non-native species play in potentially shifting food web structure–e.g., changing community membership, sequestering energy from natives? This project builds on a large breadth of research that has used stable isotopes to characterize tidal marsh food webs in the Bay-Delta and other regions.
    Science topics Food webs, Wetlands
    Updated May 8, 2024
  • Title

    Non-Invasive Environmental DNA Monitoring to Support Tidal Wetland Restoration

    Lead University of California - Davis [UC Davis]
    Description In this project we use single-species and multi-species environmental DNA (eDNA) approaches to monitor tidal wetland restoration sites and paired reference sites (existing, unrestored tidal wetlands located near restoration sites) in the San Francisco Bay Delta (SFBD). We are working in coordination with the CDFW Fish Restoration Program (FRP) and other collaborators so our eDNA detections can be paired with physical detections of fishes from their trawling efforts. Ultra-sensitive DNA single species detection methods are being used to identify restoration site use by listed species (Delta Smelt, Longfin Smelt, winter- and spring-run Chinook Salmon) while the DNA metabarcoding approach will evaluate entire fish communities (groups of different fish species) at restored and reference sites. Aside from revealing restored habitat use by other fishes, metabarcoding will reveal potential ecological interactions between Endangered Species Act listed and non-listed species, through concurrent detection in time and space. Sampling throughout the year will allow us to identify seasonal trends in fish use of restored and reference sites. This project will demonstrate the utility of eDNA detection as a non-invasive (no take), cost-effective monitoring tool that can complement conventional surveys of restored tidal wetlands in the SFBD. Our results can be incorporated into an adaptive monitoring framework for tidal wetland restoration, to increase success of future restoration projects.
    Science topics Chinook Salmon, Delta Smelt, Endangered species, Estuaries, Fish, Green sturgeon, Habitat, Habitat restoration, Invasive / non native species, Invertebrates, Longfin Smelt, Mollusks, Pelagic fish, Restoration, Restoration planning, Sacramento Splittail, Salmon migration, Salmon rearing, Steelhead Trout, Striped bass, Sturgeon, Tidal wetlands, Wetlands, White Sturgeon
    Updated May 24, 2024
  • Title

    From Microbes to Zooplankton, What Defines a Beneficial Wetland?

    Lead San Francisco State University, Estuary & Ocean Science Center
    Description Our study will characterize species diversity at multiple levels of biological organization in the water column of restoring wetlands in the upper San Francisco Estuary and Delta (SFE), from bacteria to fishes. In doing so, we will also describe the foodweb benefits being provided to larval fishes, including longfin smelt, through additional dietary DNA analysis. We will use the species diversity we find in the water column to identify a subset of biota that are indicative of the conditions present in wetlands in different stages of restoration (early, intermediate, and mature) and identify connections between those indicators to the foodweb resources being provided to higher trophic levels. We will study 3-4 wetlands in each of 3 stages: early (unvegetated), intermediate (partially vegetated and partially channelized), and mature (fully vegetated and channelized) wetlands.
    Science topics Crustaceans, Cyanobacteria, Estuaries, Fish, Food webs, Habitat, Habitat restoration, Insects, Invertebrates, Longfin Smelt, Other species, Other zooplankton, Pelagic fish, Phytoplankton, Predation, Restoration, Salinity, Saltwater / freshwater marshes, Tidal wetlands, Wetlands, Zooplankton
    Updated January 31, 2024
  • Title

    Carbon Biogeochemical Cycling in Tidal Wetlands: Exploring Lateral Carbon Exchange and Sequestration Potential

    Lead University of California - Berkeley [UC Berkeley]
    Description Tidal wetlands, at the interface of land and ocean, play a critical role in carbon biogeochemical cycling and have the potential to provide major feedback to the Earth system through greenhouse gas exchange and long-term carbon sequestration. However, the efficiency of carbon sequestration in tidal systems relies on both vertical carbon exchange with the atmosphere and lateral tidal exchange with adjacent water bodies. Unfortunately, the importance of hydrologic carbon fluxes has been largely overlooked, leaving a crucial aspect of coastal wetland net carbon balance unaddressed. We employed an integrated approach to quantify vertical and lateral carbon exchange and studied their dynamics, combining eddy covariance flux measurements with on-site water quality and tidal discharge measurements, as well as manual 24h surface water samplings. Our measurements were conducted in a recently restored tidal freshwater marsh in the Sacramento-San Joaquin Delta, CA, that stands out in global networks like FLUXNET and Ameriflux owing to its impressive net ecosystem exchange of -850 g C m-2 yr-1. Using wavelet decomposition, we examined the variability of carbon exchange (CO2 and CH4) across different timescales. Through information theory and mutual information analysis, we assessed the factors influencing both vertical and lateral exchanges. Our preliminary findings suggest that variability in carbon exchange is largest at the diel scale, with plant gross primary productivity and tidal fluctuations in depth having the most significant interactions with CO2 and CH4 fluxes, respectively. Furthermore, our tidal cycle samplings revealed that dissolved inorganic carbon dominates the fraction of lateral carbon loss, accounting for approximately 80% of the export. Remarkably, similarities existed between the values for net lateral carbon export and ecosystem respiration, signifying that the dissolved, terrestrial-to-ocean carbon flux could represent one of the primary fates of the fixed carbon in this tidal ecosystem. These large dissolved inorganic carbon fluxes and their chemical speciation, are important to consider when estimating the climate mitigation potential of restored tidal wetlands.
    Science topics Carbon, Carbon storage, Greenhouse gas GHG
    Updated January 30, 2024
  • Title

    Suisun Landscapes: historical ecology, functional metrics, and community priorities for landscape planning

    Lead San Francisco Estuary Institute [SFEI]
    Description

    To support management planning in Suisun Marsh, this project is developing a body of science and tools to understand past, present, and potential future changes to the Marsh’s ecological patterns, processes, and functions. This project builds on SFEI’s prior work in the Delta, extending historical ecology mapping, landscape change studies, and the Landscape Scenario Planning Tool to cover Suisun's historical and present-day landscapes. Through spatially explicit representations of the historical function and condition of the marsh and analyses of landscape metrics, this project is evaluating changes over time in landscape support for ecosystem functions and services in Suisun. In order to incorporate diverse perspectives into planning resources, project activities include engagement with local tribes and community members to understand community interests, priorities, and uses of the Marsh. Findings will be shared through a report and article for both technical and general audiences, and spatial analyses and data layers will be made available through the Landscape Scenario Planning Tool.

     
    Science topics None specified
    Updated October 10, 2024