15/09/2016

Spatial and temporalpollution patterns in western

Baltic Sea sediments

Dennis Bunke

Thomas Leipe, Olaf Dellwig, Marion Abraham,

Matthias Moros & Helge W. Arz

dennis.bunke@io-warnemuende.de

Spatial and temporal pollution patterns 15/09/2016

Surrounded by 9 highly industrialised countries

Anthropogenic impact by commercial use (fishery, maritime traffic & constructions)

Industry & agriculture still main sources of contamination through river discharge & air pollution (HELCOM, 2011)

Heavy metals (e.g., Hg, Pb, Zn)

Organic pollutants (e.g., PCBs, PAHs, organotin compounds)

Artificial radionuclides(e.g., 137Cs, 241Am)

Introduction: Baltic Sea

2(HELCOM, 2006)

Spatial and temporal pollution patterns 15/09/2016

Eastern Gotland Basin:

Only reasonable in areas with continuous sedimentation and limited post-depositional disturbance (like Gotland Basin)

Introduction: Pollution history

3

Spatial and temporal pollution patterns 15/09/2016

Shallow mud basins (up to 50 m deep) esp. influenced by storms and saline water inflows

Study area: Western Baltic Sea

4

EMB058/6-2WD: 42 m

Data source: iowtopo2, Seifert et al. (2001)

Spatial and temporal pollution patterns

Pollution reconstruction

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Arkona Basin:

Mono- & diorganotin compounds as stabilising additive in PVC (1940ies)

Tributyltin (TBT) in antifouling paints for marine vessels (1960ies)

TBT accumulates in marine organisms and causes endocrine disorders, e.g., in molluscs

1989: ban for boats < 25 m

2008: total ban

UV photolysis and microbial activity degrades TBT to DBT and MBT (half-live of up to 10 years in sediments)

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EMB058/6-2WD: 42 m

Master’s thesis of Lina Westphal (2015)

Spatial and temporal pollution patterns 15/09/2016

Strong wind and wave induced resuspension and sediment transport

Study area: Mecklenburg Bight

6

EMB058/2-2WD: 22 m

Data source: iowtopo2, Seifert et al. (2001)

Spatial and temporal pollution patterns

Pollution reconstruction

15/09/2016

Mecklenburg Bight:

Nearly parallel profiles due to biological and physical sediment mixing processes

General pollution trends and inventory calculations

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EMB058/2-2WD: 22 m

Spatial and temporal pollution patterns 15/09/2016

Direct anthropogenic impact by bottom trawling

Study area: Arkona Basin

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EMB058/15-2WD: 46 m

Data source: iowtopo2, Seifert et al. (2001)

Spatial and temporal pollution patterns

Pollution reconstruction

15/09/2016

Arkona Basin:

No decline towards surface due to strong (anthropogenic?) sediment mixing processes

9

EMB058/15-2WD: 46 m

Spatial and temporal pollution patterns

Recent pollution

15/09/2016

SECOS: The service of sediments in German coastal seas (e.g., storage of contaminants)

Geochemical mapping of surface sediments (0-2 cm)

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Spatial and temporal pollution patterns 15/09/2016

Dumping sites in Mecklenburg Bight (smelter waste) and Arkona Basin (presumably from WWII)

Geochemical “aureoles” indicate general sediment transport from west to east

Recent pollution: Mercury

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Spatial and temporal pollution patterns

Recent pollution: Mercury

15/09/2016

Oder Lagoon acts as stopover of pollutants from former highly polluted Oder River

Ongoing transport of (old) contaminated material from Oder Lagoon to open Baltic Sea

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Spatial and temporal pollution patterns

Recent pollution: Zinc

15/09/2016

Similar patterns for other heavy metals

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Spatial and temporal pollution patterns

Recent pollution: Organotin compounds

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Highest concentrations near local Hg hot spots in MB and AB

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Spatial and temporal pollution patterns 15/09/2016

Conclusion

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Anthropogenic induced contaminants provide insights into pollution history since pre-industrial times

Parallel Hg and 137Cs measurements useful to assess suitability of event stratigraphy and 210Pb dating for certain sediment cores

Sediments from western Baltic Sea basins only partly suitable for dating due to natural and anthropogenic sediment mixing processes

Dumping sites appearing as hot spots surrounded by aureoles of contaminated material

General sediment transport from west to east

Contaminated sediments from the Oder Lagoon still source of pollution

Thank you for your attention!