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.

Management actions relevant to the eutrophication of estuarine and coastal waters are hampered by a lack of long-term nutrient concentration data. Implementation of the European Union Water Framework Directive will require member states to obtain such historical information to aid the management of nutrients to achieve concentrations similar to those ?under minimal anthropogenic influence?.
Few monitoring programmes began before the 1970s and therefore our perspective on when changes began, and what nutrient concentrations were prior to anthropogenic impact is constrained by a lack of historical data. Diatom-based transfer functions, a quantitative palaeoecological technique, offer a methodology that can be used to assess background conditions, and the degree of past and present departure from such conditions.
The MOLTEN project developed diatom-based transfer functions for nutrient concentrations (N & P) from four European coastal zones: the Netherlands, Denmark, Sweden and Finland. Nutrient reconstructions from Denmark and Finland are presented here. Canonical correspondence analysis (CCA) and partial CCA with forward selection as assessed by Monte Carlo permutation tests were used to define variables that significantly and uniquely explained variation in the diatom data. Transfer functions were developed through weighted averaging partial least squares (WA-PLS).
The reconstruction of total nitrogen (TN) from Roskilde Fjord in Denmark indicated that concentrations of TN had nearly doubled between the start of the 20th century and 1995. The most rapid increase in TN concentration occurs after the mid 1950s, corresponding to the post-war increase in artificial fertiliser use. A reconstruction of total dissolved nitrogen (TDN) from Laajalahti, an urban embayment near Helsinki, revealed a different history of nutrient enrichment. Increases in TDN were associated with growing waste water inputs, decreases in TDN followed the introduction of tertiary treatment facilities.
Work carried out within MOLTEN resulted in the analysis of the distribution of diatom assemblages from over 200 surface sediment samples throughout north western Europe. A wealth of high quality environmental data available to be modelled against the diatom assemblages allowed the development of robust transfer functions, and also provided much needed information on the distribution, optima and tolerances of marine and estuarine diatom taxa.
Diatom-based transfer functions are recognised in freshwater and saline lake research as a valuable tool for the quantitative reconstruction of past environments. Transfer functions are less frequently used in coastal and marine environments, while diatom taxa with poorly-defined ecological requirements are commonly used to qualitatively indicate environmental change. MOLTEN indicates that diatom-based transfer functions for nutrient concentrations can be applied to coastal environments. The taxa-environment relationships defined during transfer function development provide useful data on the ecological requirements for many taxa where this data is scarce or entirely missing.

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.