Coastal ecology and palaeoecology of the Baltic and adjacent seas
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Molten team (2004) MOLTEN management tool .
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Molten Team (2004) MOLTEN transfer function user guide .
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Molten Team (2004) MOLTEN transfer function software .
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Clarke, A.L., Juggins, S., and Conley, D.J. (2003) A 150-year reconstruction of the history of coastal eutrophication in Roskilde Fjord, Denmark. Marine Pollution Bulletin 46: 1615-1618.

Reuss, N., Conley, D.J. & Bianchi, T.S. (2005) Preservation conditions and the use of sediment pigments as a tool for recent ecological reconstruction in four Northern European estuaries Marine Chemistry 95: 283-302.

Clarke, A. L., Weckström, K, Conley, D. J., Anderson, N. J., Adser, F., Andrén, E., de Jonge, V. N., Ellegaard, M., Juggins, S., Kauppila, P., Korhola, A., Reuss, N., Telford, R. J., Vaalgamaa, S. (2005) Long-term trends in eutrophication and nutrients in the coastal zone. In press, Limnol. Oceanogr..

Weckström, K (Submitted) Assessing recent eutrophication in coastal waters of the Gulf of Finland (Baltic Sea) using subfossil diatoms. Journal of Paleolimnology..

Weckström, K., Juggins, S. & Korhola, A. (2004) Quantifying background nutrient concentrations in coastal waters: A case study from an urban embayment of the Baltic Sea. Ambio 33(6): 324-327..

Weckström, K. & Juggins, S. (In Press) Coastal diatom-environment relationships from the Gulf of Finland, Baltic Sea. Journal of Phycology..

Kauppila, P., Weckström, K., Vaalgamaa, S., Pitkänen, H., Korhola, A., Reuss, N. & Drew, S. (2005) Tracing pollution and recovery using sediments in an urban estuary, the northern Baltic Sea: Are we far from ecological reference conditions? Marine Ecology Progress Series 290: 35-53..

Weckström, K., Korhola, A. & Shemeikka, P. (2002) Physical and chemical characteristics of shallow embayments on the southern coast of Finland. Hydrobiologia 477: 115-127.
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Andrén, E. (2005) Naturliga halter - vad är det? Historiska arkiv ger referensvärden. Miljötillståndet i Egentliga Östersjön Rapport 2005. tockholm Marine Research Centre, available on

Andrén, E. (2005) Oral presentation broadcasted from the Swedish digital TV channel "Kunskapskanalen" 16 Mars 2005. Available from the web.

Clarke, A.L., Weckström, K. & Andrén, E. (2002) Diatom-based transfer functions as a tool to study coastal eutrophication: the MOLTEN project. 17th International Diatom Symposium Ottawa, Canada 25-31 August, 2002.

Clarke, A.L. & Juggins, S. (2001) A diatom-based transfer function to infer historical changes in total nitrogen from coastal sediments. Invited oral presentation at ERF 2001: An Estuarine Odyssey 16th Biennial Conference of the Estuarine Research Federation St. Pete Beach, Florida, U.S.A. 4-8 November 2001.

Ellegaard, M. (2002) Dinoflagellate cysts as potential indicators of nutrient levels in the past. 10th International conference on harmful algae blooms St. Pete Beach, Florida. 20-25 October 2002.
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Andrén, E., Clarke, A. & Weckström, K. (2004) Defining reference conditions for coastal areas in the Baltic Sea for the Water Framework Directive. Ten-year Jubilee Conference of the Foundation for Baltic and East European Studies, Sweden, 23-25 September 2004..

Clarke, A. (2004) Oral Oral presentation at the 18th International Diatom Symposium, Polen, 2-7 September 2004..

Clarke, A. (2005) Oral Oral presentation at the ASLO Aquatic Science Meeting, USA, 20-25 February 2005..

Conley, D. (2005) Oral Oral presentation at the HELCOM EUTRO meeting, January 2005..

Korhola, A. (2005) Oral Oral presentation at BIREME Annual Symposium, Finland, 9-11 February 2005..

Vilbaste, S., Andrén, E., Clarke, A., Telford, R. & Weckström, K. (2005) DEFINE - continuation of EU MOLTEN project. Preliminary results - diatoms from Estonian coastal waters. Nordic Diatomist Meeting, Estonia, 20-23 May 2005..

Weckström, K. & Juggins, S. (2005) Coastal diatom-environmental relationships from the Gulf of Finland, Baltic Sea. Poster presentation at the ASLO summer meeting, Spain, 19-24 June 2005..

Vaalgamaa, S. (2002) The eutrophication history of Laajalahti Bay, Helsinki City, as reflected by sediment geochemistry. ASLO 2002 Summer Meeting Inter-disciplinary Linkages in Aquatic Sciences and Beyond, Victoria, British Columbia, Canada.

Weckström, K., Vaalgamaa, S., Kangas, J. & Shemeikka, P. (2004) Hellänlahden rehevöitymishstoria paleolimologisin menetelmin arvioituna. [The eutrophication history of Hellänlahti - an assessment using palaeolimnological methods] Raportti Kaakkois-Suomen ympäristökeskukselle. 15 s. [Scientific Report to the Southeast Finland Regional Environment Centre. 15 p.].

Weckström, K., Vaalgamaa, S., Kangas, J. & Shemeikka, P. (2004) Uudenmaan merenlahtien rehevöitymishistoria paleolimnologisin menetelmin arvioituna: Pieni Pernajanlahti, Fasarbyviken, Varlaxviken, Nikuviken, "Insjön" ja Sipoonlahti. [The eutrophication history of coastal embayments in Uusimaa - an assessment using palaeolimnological methods: Pieni Pernajanlahti, Fasarbyviken, Varlaxviken, Nikuviken, "Insjön" and Sipoonlahti.] Raportti Uudenmaan ympäristökeskukselle sekä Porvoon, Pernajan ja Sipoon kunnille. 24 s. [Scientific Report to the Uusimaa Regional Environment Centre and the cities of Porvoo, Pernaja and Sipoo. 24 p.].

Clarke, A.L. (2001) A diatom-based transfer function to infer historical changes in total nitrogen concentration from coastal sediments: a case study from Roskilde Fjord, Denmark. PhD Thesis, University of Newcastle upon Tyne.

Coastal eutrophication is now recognised as a major environmental problem. Over the past three decades it has become apparent that increases in nutrient concentrations can lead to serious degradation of coastal ecosystems, particularly in areas that are densely populated. Progress in remedial action has been hampered in part by a lack of long-term records detailing the rate and direction of changes in nutrient concentrations of coastal ecosystems. This research developed a transfer function to reconstruct concentrations of total nitrogen (TN) from the palaeoecological record of diatom valves preserved within coastal sediments.
A 70-site calibration set, composed of percentage abundance counts of diatom taxa from surface sediments and corresponding water quality records, was constructed from sub-tidal sampling locations within Denmark. Canonical correspondence analysis (CCA) with forward selection indicated that five environmental variables explained a statistically significant proportion of the variation within the diatom data, with TN uniquely explaining 2.5 % of the variation.
Weighted averaging partial least squares (WA-PLS) was used to create a transfer function to reconstruct TN from fossil diatom counts. Application of the TN transfer function to a core from Roskilde Fjord, Denmark indicated that concentrations of TN had nearly doubled to 91 micromol/l between the turn of the 20th century and 1995. The most rapid increase in TN concentration was seen in the years post 1956, which corresponds to the post-war increase in the use of artificial fertiliser.
This research has indicated that Danish coastal sediments hold a record of recent environmental change as indicated by changes in the structure of fossilised diatom assemblages. The quantitative nature of the reconstruction allows the degree of change to be assessed in terms readily accessible to environmental managers, and so can be used to set targets for nutrient reduction schemes. The methodology also has applicability to the Water Framework Directive by providing means to determine conditions of minimal human impact on nutrient concentrations.