Impacts of Multiple Stressors on Water Quality in Saginaw Bay

Juli Dyble, Gary Fahnenstiel, Tom Nalepa, Hank Vanderploeg NOAA Great Lakes Environmental Research Lab

Tom JohengenCILER

Scott Peacor, Dianna Dziekan, Kim PetersMichigan State University

Steve Francoeur Donna Kashian Eastern Michigan University Wayne State University

Jim Bredin, Bruce Walker Joe Depinto Michigan DEQ LimnoTech

Peter Lavrentyev Dave Millie University of Akron Florida Institute of Oceanography

2008• 3 monthly surveys (May, July, Sept)• 10 inner bay, 3 outer bay stations • 5 Master stations (surface and bottom)

2009• 6 monthly surveys (May – Oct)• 10 inner bay, 3 outer bay stations, 2 water intakes• 5 Master stations (surface and bottom)

2010 • 6 monthly surveys (May – Oct)• 10 inner bay, 1 outer bay stations, 2 water intakes• 5 Master stations (surface and bottom)

Samples collected

Sampling stations

Blue: Master (5) Red: Basic (8)

Water utility intakes

Physical • CTD: temperature, conductivity, PAR, transmittance, DO• Secchi depth

Chemical• total P, SRP, TDP, particulate CN, DOC, NO3, NH4, SiO2, Cl• TSS, VSS

Phytoplankton• chl a• phytoplankton cell counts• phytoplankton groups for algal pigments (HPLC)• Microcystis and microcystin (master stations and water intakes)

Zooplankton and microzooplankton• vertical tows w/ 64 um net (master stations)• oblique tows for larger bodied zooplankton (master stations)• whole samples in lugols and formalin (to Peter Lavrentyev)

Parameters measured

Physical • CTD (temp, PAR, DO, Chl and PC fluorescence) – downloaded • Secchi depth - logged

Chemical• total P, SRP, TDP, NO3, NH4, SiO2, Cl – 2008, 2009, 2010• particulate CN - 2008, 2009 (2010 in process)• DOC – 2008, 2009, 2010• TSS, VSS – 2009, 2010

Phytoplankton• chl a - 2008, 2009, 2010• phytoplankton cell counts – 2008, 2010 (2009 likely not available)• phytoplankton groups for algal pigments (HPLC) – not done• Microcystis and microcystin – (2010 in process)

Zooplankton and microzooplankton• vertical tows w/ 64 um net (master stations) – 2009 (2010 in process)• oblique tows for larger bodied zooplankton (master stations) • whole samples in lugols and formalin (to Peter Lavrentyev)

Status of sample processing

Avg surface temp (2008-2010)

May Jul Sept0

5

10

15

20

25

30SB 2

200820092010

tem

p (°C

)

May Jul Sept0

5

10

15

20

25

30 SB 5

200820092010

tem

p (°C

)

May Jul Sept0

5

10

15

20

25SB 10

200820092010

tem

p (°C

)

May Jul Sept0

5

10

15

20

25SB 20

200820092010

tem

p (°C

)

SB2

SB5

SB14

SB10

SB20

Average yearly TP (2008-2010)

May June Jul Aug Sept Oct0

10

20

30

40

50

60

SB2

SB5

SB10

SB14

SB20

TP (u

g/L)

Driven by 2010values

Driven by 2009values

SB2

SB5

SB14

SB10

SB20

Average yearly chl a (2008-2010)SB2

SB5

SB14

SB10

SB20

May June Jul Aug Sept Oct0

5

10

15

20

25

30

35SB2SB5SB10SB14SB20

chl a

(ug/

L)

Proposed chla resulting from 15 ug P/L in Saginaw Bay, 1979 P mgmt strategies workshop

3.6 ug/L

Chl a vs TP

R2 = 0.6645

R2 = 0.4214

R2 = 0.5982

Phyto community analysis – 2008(% of total biovolume)

SB2

SB5SB14

SB10

SB20

SB2

May 08

July 08

Sept 08

Bacillariophyta

Chlorophyta

Cryptophyta

Cyanobacteria

Chrysophyta

SB5 SB14

Phyto community analysis – 2008(% of total biovolume)

SB2

SB5SB14

SB10

SB20

SB10

May 08

July 08

Sept 08

SB20BacillariophytaChlorophytaCryptophytaChrysophytaCyanobacteria

Many Thanks to:

Ashley BurtnerDanna PalladinoDuane Gossiaux

Nancy MoreheadJoann CavalettoDave Fanslow

Steve ConstantLee Wyrobek

Dennis DonahueAndrew Yagiela

Mike TaetschTom Joyce

Jack Workman