San Francisco Bay Estuary Lab

San Francisco Bay Estuary

Where land and sea come together

Watersheds

Approximately 40% of California’s water drains out to the Pacific Ocean through the bay.

 The land area drained by a river and its tributaries.  Sacramento  San Joaquin  San Francisco Bay

Historical view (circa 1800)

Estuary & Wetlands  Edges of the bay were

dominated by tidal wetlands.

 Tidal wetlands provide wildlife habitat, flood prevention, and sediment management.

 These wetlands are sensitive habitats for small mammals, migratory birds and fish species, many of which are threatened or endangered.

Courtesy of SFEI

 Wetlands are buffer zones.  Stabilize shorelines & protect coastal and inland

areas from floods and storm surges.  Protect streams, river channels and coastal shores

from excessive erosion caused by wind & water.

Estuary & Wetlands

Estuary & Wetlands  Inflowing water brings nutrients from

surrounding watershed.  Trap sediment & filter water of pollutants.  For this reason, estuaries are some of the most

fertile ecosystems on Earth, yet they may also be some of the most polluted.

 Productivity is high because shallow in most places. Sunlight can penetrate to the bottom.

 Unique home to fish, birds, beaver, otter, fox, weasel, seals, jellyfish, oysters, etc…

 Critical habitat for migratory birds, butterflies, & anadramous fish.

Estuary Ecosystem

California clapper rail

Chinook smelt

Estuary Ecosystem

 Lost ~80% of historic tidal wetlands

 Immediate loss of estuarine habitat

 Ag, urban, & shipping channels

 Increased pollution  Poor water quality

effects most estuary organisms

Landuse Change in the SF Bay Estuary

Landuse Change in the SF Bay Estuary

Pink = landfill Cyan = drained marsh or wetland

 Chlorophyll  Flow of nutrients (P & N) has increased into estuary waters.

 This increase of P & N inputs has lead to massive blooms of algae in the estuary, which is known as eutrophication.  Can lead to hypoxia, i.e. depleted oxygen levels

within the water.  Excess nitrogen from fertilizers.

Water Quality

Nitrate in San Joaquin River

Pssst…. P = phosphate & N = nitrogen

 Salinity  Fresh water can hold more dissolved oxygen (DO)

than salt water

Water Quality

 Temperature  Cold water holds more dissolved oxygen (DO)

Water Quality

 Dissolved Oxygen  Waves and wind help put oxygen into water  Healthy waters should be >80% saturation (>5 mg/L)

Water Quality

 Suspended Sediment  Sediments present in the estuary as a result of soil

erosion, urban runoff, wastewater effluent, decay, and wind / wave action.

 Transport adsorbed contaminates, blocks sunlight, absorbs heat, and clogs the gills of fish.

Water Quality

 USGS Polaris

Water Quality

 Monthly water quality analysis of the bay since 1960s.

Spatiotemporal variability

January 22, 2015 September 24, 2015

Other Estuary Health Issues  Hazardous materials

 Sediment (mercury/heavy metals), oil (spills & refinery wastes, chemicals/acids from industry, WWII waste (munitions/ships), radioactive waste.

 Liquefaction  Climate change (sea level rise)  Stormwater, waste water  Dams & levees

2016 Ballot Measure AA  San Francisco Bay Restoration Authority “Clean

and Healthy Bay” Parcel Tax  $12/year parcel tax, no matter property value  $500 million over 20 years  Earmarked for restoring wetlands

 Reducing trash, pollution and harmful toxins, improving water quality, restoring habitat for fish, birds and wildlife, protecting communities from floods, and increasing shoreline public access.

Homework  Complete Estuary Reading Quiz

 Friday before midnight  San Francisco Bay Estuary Lab

 All details explained in PDF on iLearn  References section is required!!  5 sources are the absolute minimum  WIKIPEDIA DOES NOT COUNT!

 Due before class next Monday via Turnitin

Have a great week!!