RobinStewartandMickJagger,USGS

ContaminantswillplayanimportantroleinassessingoutcomesofscenarioschangeintheBay‐Delta:

Hydrology

Ecology

WithintheCASCaDEcontaminants:

IntegrateecosystemprocessesandInfluencepopulationdynamics

Scenario Climate +

Infrastructure

Source SJR/Sac

Concentration

Chemical Speciation

Aqueous [Contaminant]

Residence Time

Recycling

RisktoHumans

Geochem/ Geomorph

(Jaffe, van der Wegen)

Hydrology (Knowles/ Monsen)

Phytoplankton Uptake

Scenario Climate +

Infrastructure

Fish Population Dynamics (Brown et al.)

PopulationImpact

Proportional Loss of Recruitment

Phytoplankton Biomass/Source (Lucas) Ecological

Effects

Secondary Production Invasive Species (Thompson/Parchaso)

Phytoplankton Uptake

Invertebrate Uptake

Scenario Climate +

Infrastructure

Source SJR/Sac

Concentration

Phytoplankton Uptake

Invertebrate Uptake

Trophic Transfer

Fish Body Burden Organism

Toxicity

RisktoHumans

RisktoWildlife

Fish Population Dynamics (Brown et al.)

PopulationImpact

Proportional Loss of Recruitment

Chemical Speciation

Phytoplankton Biomass/Source (Lucas) Ecological

Effects

Secondary Production Invasive Species (Thompson/Parchaso)

Aqueous [Contaminant]

Residence Time

Recycling

RisktoHumans

Geochem/ Geomorph

(Jaffe, van der Wegen)

Hydrology (Knowles/ Monsen)

OrganismToxicity

Biodynamic Modeling (Luoma/Stewart)

BiodynamicmodelconceptPhysiology:Uptake&

LossRates

Uptakeratefromsolution Uptakerate

fromfoodRateconstant

ofloss

Environment:Concentration&Form

Metalinfood

Metalinsolution

Physicochemicalform

BioaccumulationScenario

ObservedBioaccumulation

SiteX

Metalinfood

FunctionalEcology

Biology

GrowthConventional

BAF

BiodynamicModelParameters

ku[C]w+AE∙IR∙[C]food

ke+kg

steady‐state[Contam.]org=

Uptakefromwater&food

Lossfromeffluxandgrowth

Fieldmeasured[C]w(ug/L)[C]food(μg/gfood)

Laboratoryderivedku(/d) AE(%fromfood)ke(/d) IR(gfood/gtiss∙d)kg(/d)

=

SeleniumPrimer‐Toxicology

SesubstitutesforSinionicdisulfidebondsofproteins⇒ tertiarystructures

(e.g.tissues)

AdultMosquitofishElement–metalloid,sulfuranalogue,

inorganiccontaminantNutrient–requiredbyacellular

antioxidantenzymePoison‐potentteratogen

PresserandLuoma,2006

SeleniumPrimer‐Sources

AgricultureIrrigation

Oilrefineries

TheamountandproportionofSanJoaquin(Seleniumsource)relativetoSacramentoRiverwaterenteringtheBay‐Deltawilllikelychangeunderdifferentscenarios

TheSeleniumCASCaDE

San Francisco Bay/Delta (Courtesy of Nancy Monsen)

WatershedinflowstoSJR:SACDeltaingfdl-a2 scenario

90% percentile

SJR

:SA

C W

ater

shed

inflo

ws

Preliminary

SeconcentrationsinCorbulahavechangedovertime

Extend dataset

through 2008

Cor

bula

Se

conc

. (µg

/g d

ry w

t.)

Leng

th-a

djus

ted

@ Carquinez St.

SeconcentrationsinCorbulahavechangedovertime,butperhapsfordifferentreasons

Extend dataset

through 2008

Cor

bula

Se

conc

. (µg

/g d

ry w

t.)

Leng

th-a

djus

ted

Refinery modifications

HigherSefood[Cf]

HigherSefood[Cf]HigherIRduetomore

food

AE∙IR∙[C]food

ke+kg[C]org=

1931

19771989

≈1psu

1983

DistributioninNormalHydrologicYears

MaximumSalinityIntrusionCorbulaamurensis

Thompson&Parchaso

TheSeleniumCASCaDE

HowwillchangesindistributionsofclamsinfluenceSebioaccumulationandtrophictransferofSetotoppredators?

Species‐specificphysiologycanenhanceSeleniumuptake

Prey‐basedReproductiveToxicityThreshold

DifferenceinSeaccumulationatthebaseofthefoodchainispropagatedtotoppredators

δ15N Trophicposition

Selenium

con

c.(μ

g/gdrywt.)

Corbulaamurensis‐based

Estimated:Corbiculafluminea‐based

Zooplankton‐based

Stewartetal.2004

MercurytrophictransferStewartetal.2008Luomaetal.2008

0

5

10

15

20

‐32‐30‐28‐26‐24‐22

Clam δ13C

Cla

m S

e co

nc. (

µg/g

dry

wt.)

FresherSaltier

0

5

10

15

20

‐32‐30‐28‐26‐24‐22

Clam δ13C

Cla

m S

e co

nc. (

µg/g

dry

wt.)

Clam Se conc. decline upstream and between species

FresherSaltier

0

5

10

15

20

‐32‐30‐28‐26‐24‐22

Clam or W. sturgeon δ13C

Cla

m a

nd W

hite

stu

rgeo

n S

e co

nc. (

µg/g

dry

wt.)

FresherSaltier

0

10

20

30

40White sturgeon Se conc. decline upstream with Clam Se conc.

Reproductive threshold

0

5

10

15

20

‐32‐30‐28‐26‐24‐22

Clam δ13C

Cla

m a

nd W

hite

stu

rgeo

n S

e co

nc. (

µg/g

dry

wt.)

SowhathappensundermaximumsalinityintrusionintotheDeltaandweextendCorbulaoccurrenceupstream?

FresherSaltier

0

10

20

30

40

Reproductive threshold

0

5

10

15

20

‐32‐30‐28‐26‐24‐22

Clam δ13C

Cla

m a

nd W

hite

stu

rgeo

n S

e co

nc. (

µg/g

dry

wt.)

SowhathappensundermaximumsalinityintrusionintotheDeltaandweextendCorbulaoccurrenceupstream?

FresherSaltier

0

10

20

30

40

Increase in White sturgeon Se conc. upstream

Reproductive threshold

ProportionalLossofRecruitment

Conclusions  Hydrologicalandecologicalchangesdrivenbyclimate

changecouldbeinfluentialindeterminingtheimpactsofSecontaminationinthisestuary

  Usemodeltodistinguishtherelativecontributionof:FOODAVAILABILITYSECONCENTRATIONSINFOOD

  EvaluatechangesinclamtissueSeconcentrationsrelativetochangesinfoodavailabilityandSeconcentrationsinfoodunderdifferentscenarios

  Invasivespecies  Estimateimpactsonfishpopulations

Nextsteps