Trace metals phytoplankton
This presentation is the property of its rightful owner.
Sponsored Links
1 / 24

Trace Metals & Phytoplankton PowerPoint PPT Presentation


  • 118 Views
  • Uploaded on
  • Presentation posted in: General

Trace Metals & Phytoplankton. Gert Vlaming. 24-01-2003. Contents. Introduction Trace metals Importance of phytoplankton Conclusion. Gaia theory. Environment. Life. Trace metals. Fe 3+ Mn 2+ Co 2+ Cu 2+. Ni 2+ Cd 2+ Zn 2+. Trace metals of importance. Complexation field diagram.

Download Presentation

Trace Metals & Phytoplankton

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Trace Metals & Phytoplankton

Gert Vlaming

24-01-2003


Contents

  • Introduction

  • Trace metals

  • Importance of phytoplankton

  • Conclusion


Gaia theory

Environment

Life


Trace metals


Fe3+

Mn2+

Co2+

Cu2+

Ni2+

Cd2+

Zn2+

Trace metals of importance


Complexation field diagram

Whitfield, 1997


Recycled elements

  • Low concentrations in the surface layer

  • Enhanced concentrations in the deeper water

  • Residence time: intermediate (103 – 105 yrs)

  • Concentrations: 10-12 – 10-5 M


Concentrations

mol/l


Concentrations II

  • Atlantic ocean receives a greater flux of windborne dust and atmospheric contaminants than the Pacific

  • Accumulated elements released from the decaying particulate matter

  • Mn and Co: adsorption onto particles


Biochemical functions

And many enzymatic reactions


Availability

  • > 97% of the total metal in solution is held in strong organic complexes

  • These complexes are not available for phytoplanktonic uptake

The essential trace metals have very low concentrations


Importance of life for trace metal concentrations


Fractionation

Broecker & Peng, 1982


Recycling ratio

flux circulating within the ecosystem

R =

flux circulating through the environment

R

R


Recycling ratio

Whitfield, 1997


Recycling ratio II

  • The inability of phytoplankton to exercise absolute discrimination

  • Phytoplankton are capable of actively regulating their internal economy

  • For most essential trace metals the cells are at, or close to, their nutrient limitation levels


Adaptations

  • Internal

  • External

  • Interspecific

  • Collective

There’s a “chemical war” going on ...


Uptake

  • Diffusion

  • Transfer of complexes

  • Capture

  • Uptake by Michaelis-Menten kinetics


Organic complexation

  • Cells release organic complexing agents

  • Beneficial for Fe, Cu en Mn

  • Enabling large pool of Fe to be maintained

  • Maintaining concentrations below toxic levels


Conclusions

  • Availability of trace metals is a significant factor regulating primary production

  • Phytoplankton is strongly effecting the concentrations of trace metals


Questions


Additional


Evolution of life

  • Prokaryotic life: 3.5 Ga

  • Eukaryotic life: 1.5 Ga

  • Multicellular life: 600 Ma


Start of multicellular life

Possibly because:

  • Lowering of the alkalinity of the oceans

  • The attainment of an appropriately low global mean temperature

  • The maintenance of a critical level of dissolved oxygen in the sea

  • The establishment of the required cocktail of available trace metals


  • Login