Micropaleontologic investigations of harbour sediments in the Baltic Sea using ostracods

 Dietmar Keyser,Hamburg, Germany Nikolay Aladin, St.Petersburg, Russian Federation Burkhard Scharf, Bremen, Germany Peter Frenzel, Jena, Germany Igor Plotnikov , St.Petersburg, Russian Federation

Baltic Sea geological stages

Post-littorina Sea, 4000 BP-current (brackish to fresh)

Littorina Sea, 7500-4000 BP (brackish to saline)

Mastogloia Sea, 8000 BP-7500 BP (intermediate stage, fresh to brackish)

Ancylus Lake, 9500-8000 BP (cold , fresh)

Yoldia Sea, 10,300-9500 BP (cold, saline to brackish)

Baltic Ice Lake, 12,600-10,300 BP (cold, fresh to brackish)

Eemian Sea, 130,000-115,000 BP ( brackish, 3°C warmer than today)

The Baltic Sea Furman et al 2004

The Baltic Sea Furman et al 2004

Partly decalcified shell of Cyprideis torosa (Frenzel & Oertel 2002) due to acidity in the sediment

Diatom

Diatom

Diatoms

Foraminifera

Shell of an ostracod Length of carapace 0,5 mm

Cyprideis torosa ostracod, right shell of the carapace removed

Cyprideis torosa

Animal collected in Salinity <10‰

Animal collected inSalinity > 6‰

Appearance of nodes in the population of Cyprideis torosa is connected with thesalinity of the surrounding water. Nodes appear when the salinity drops below the innerosmolarity of 6 ‰ in the animal (Keyser et al. 2004).

Hemicytherura cellulosa

Loxoconcha ellipticaHirschmannia viridis

Semicytherura striata

Palmenella limocolaHemicythere villosa

Acantocythereis dunelmensis

Sediment cores

will be taken

by gravity corer

and the sediment

collected every

centimeter

Unprocessed sample of ostracods

Processed sample of ostracods

Cytheromorpha fuscata (Brady, 1869)Depth     1-30m

Substrate   vegetation x

    detritus  

    sand Coarse  

      Medium xx

      Fine  

    Mud --

    Silt  

Salinity     1-18 psu

Temperature     0-30°C

Waterchemistry   pH 9,1-9,5

    H2S  

    O2  

Watercurrent     Unknown

Seasonality     Whole year

Fossil     Quaternary

Assemblages Occurring together with

Cyprideis torosa, Elofsonia baltica, Leptocythere lacertosa, Xestoleberis aurantia, Cytherura gibba, Loxoconcha elliptica, Darwinula stevensoni

 

♀ dorsal view

Copulatory organ

Expected achievements of the study

1. biodiversity of ostracods in the entire Baltic

2. evaluation of historic sediments.

3. variation of biosystems.

4. variations in salinity, temperature, sediment, plant growth

5. Influences of oil derivatives and antifouling compounds

6. sediment acidity

7. Invading species

Proposal to HELCOM MONAS

•HELCOM MONAS is asked to include a monitoring

program for meio - zoobenthos into COMBINE•HECOM MONAS is asked to urge the adjacent states to support the scientists

working in this group in setting up and maintaining a laboratory facility as

well as in collecting the samples.

•The group should meet annually and give a report.

•The meio-zoobenthos group has to work in close cooperation with the other

groups of MONAS and HELCOM.

•The data received must be included in a meta database like NOKIS (Germany) or

others, to be readily available for all interested parties.

Following goals should be worked on:

- Biodiversity

- Distribution

- Seasonality

- Ecological borders

- Influence of new invading species

•an internet manual of all known species has to be updated and maintained by the group and access should be free of charge.

•Funds should be provided for specialists exchange

•Joint work should be promoted

• The ostracod group should start to monitor the meio-zoobenthos.

Thank You

for Your

attention