role of infochemical-mediated feeding in planktons

Role of Infochemical-Mediated Feeding in Multitrophic Plankton

InteractionsNicola Lewis

ndlewi@essex.ac.uk

Supervisors: Edd Codling and Michael Steinke G. Gorick

H3C CH3

S

rc

rp

Breckels et al. (2011) J Plankton Res 33: 629-639

How do zooplankton find prey?

CH3

H3CS+ COO- COO-H2C

H

C H+

DMSP DMS Acrylate

DMSP lyase

H3C

H3CS

+Steinke et al. (2002) J Phycol 38: 630-638

Tritrophic Model – Methods

Pk

gPM

K

PrP

dt

dP

1

Pk

gPMmM

Pk

gPM

dt

dM

2

Phytoplankton growth

Microzooplankton grazing

Microzooplankton mortality(absence of DMS)

Microzooplankton mortality(presence of DMS)

Lewis et al. (2011) Biogeochem, DOI: 10.1007/s10533-011-9649-0.

r

K

k

g

Tritrophic Model – Methods

Z

Production rate of DMS

Copepod predation rate

Density/ abundance of copepods

Increase in copepod predation (through chemodetection)

Rate DMS leaves the system

Lewis et al. (2011) Biogeochem, DOI: 10.1007/s10533-011-9649-0.

Tritrophic Model – Results M

icro

zoo

pla

nkt

on

Phytoplankton Time

dP/dt=0

dM /dt=0

Ph

yto

pla

nkt

on

/ Mic

rozo

op

lan

kto

n

Phase Portrait Temporal Graph

1. No DMS effect

Lewis et al. (2011) Biogeochem, DOI: 10.1007/s10533-011-9649-0.

×

×

Tritrophic Model – Results M

icro

zoo

pla

nkt

on

Phytoplankton Time

dP/dt=0

dM /dt=0

Ph

yto

pla

nkt

on

/ Mic

rozo

op

lan

kto

n

Phase Portrait Temporal Graph

1. No DMS effect

Lewis et al. (2011) Biogeochem, DOI: 10.1007/s10533-011-9649-0.

×

×

Tritrophic Model – Results M

icro

zoo

pla

nkt

on

Phytoplankton Time

dP/dt=0

dM /dt=0

Ph

yto

pla

nkt

on

/ Mic

rozo

op

lan

kto

n

Phase Portrait Temporal Graph

1. No DMS effect

Lewis et al. (2011) Biogeochem, DOI: 10.1007/s10533-011-9649-0.

×

×

Tritrophic Model – Results M

icro

zoo

pla

nkt

on

Phytoplankton Time

dP/dt=0

dM /dt=0

Ph

yto

pla

nkt

on

/ Mic

rozo

op

lan

kto

n

Phase Portrait Temporal Graph

1. No DMS effect

Lewis et al. (2011) Biogeochem, DOI: 10.1007/s10533-011-9649-0.

×

×

Tritrophic Model – Results M

icro

zoo

pla

nkt

on

Phytoplankton Time

dP/dt=0

dM /dt=0

Ph

yto

pla

nkt

on

/ Mic

rozo

op

lan

kto

n

Phase Portrait Temporal Graph

1. No DMS effect

Lewis et al. (2011) Biogeochem, DOI: 10.1007/s10533-011-9649-0.

×

×

Tritrophic Model – Results

Phase Portrait Temporal Graph

× ×

Mic

rozo

op

lan

kto

n

Phytoplankton

Ph

yto

pla

nk

ton

/ M

icro

zoo

pla

nk

ton

Time

2. Low DMS effect

Lewis et al. (2011) Biogeochem, DOI: 10.1007/s10533-011-9649-0.

Tritrophic Model – Results

Phase Portrait

Mic

rozo

op

lan

kto

n

Phytoplankton

× ×

×

Separatrix

Ph

yto

pla

nk

ton

/ M

icro

zoo

pla

nk

ton Temporal graphs

3. Mid DMS effect

Lewis et al. (2011) Biogeochem, DOI: 10.1007/s10533-011-9649-0.

Tritrophic Model – Results

Phase Portrait Temporal Graph

× ×

Mic

rozo

op

lan

kto

n

Phytoplankton Time

Ph

yto

pla

nk

ton

/ M

icro

zoo

pla

nk

ton

4. High DMS effect

Lewis et al. (2011) Biogeochem, DOI: 10.1007/s10533-011-9649-0.

Competition?

DMSP as a deterrent!

Competition?

DMSP as an attractor!

Competition?

Competition?

No DMS production!

Conclusions

• Infochemicals such as DMS are important for zooplankton in the search for suitable prey.

• Grazing-induced DMS may affect the susceptibility of microzooplankton to predation by copepods.

• Infochemical mediated feeding in the plankton may create a refuge from grazing for phytoplankton through the promotion of multitrophic interactions

Acknowledgments

UoEEdd Codling

Michael SteinkeMark Breckels

OthersAndrew Morozov

Jon PitchfordSteve Archer