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DatoValore
TitleHigh resolution analysis of fossil pigments, carbon, nitrogen and sulphur in the sediment of eight European alpine lakes: the MOLAR project.
AbstractA palaeoenvironmental reconstruction for the past 2-3 centuries of eight remote sites from northern to southern Europe was based on a number of palaeolimnological proxies, especially fossil pigments. Most of the lakes studied are located above the timberline and a great effort centred on the creation and analysis of a data-sets of sedimentary records. A chronology for the last century was based on radiometric techniques (210Pb, 241Am 137Cs). The accumulation rate of recent sediment was found to vary from 0.041 cm y-1 (Lake Saanajärvi, Finland) to 0.14 cm y-1 (Jezero v Ledvici, Slovenia). During the time-span represented by the cores were the major changes in organic carbon and nitrogen in Ni?né Terianske Pleso (Slovakia), Redó (Spain) and Gossenköllesee (Austria). Constant increase of these nutrients from AD 1900 onwards was shown in lakes Saanajärvi, Ni?né Terianske Pleso and Hagelseewli (Switzerland). No common trends in sulphur concentrations was evident. There is evidence of an atmospheric input of sulphur in Hagelseewli. This lake shows the highest concentrations, 10 fold higher at surface than the other lakes (ca 6% d.m.). A decrease of S during very recent times is clearly shown by the cores from Redò and Hagelseewli: this might be related to the reduction in the atmospheric loading (the matching of the atmospheric and sedimentary sulphur trends favours this hypothesis). Concentrations of total pigments and HPLC single carotenoids and chlorophylls showed marked fluctuations throughout the cores of all lakes. High pre-AD 1800 pigment concentrations were detected in Ni?né Terianske Pleso, Redó, Hagelseewli and Gossenköllesee. During the last ca 50 years an increase in productivity inferred from fossil pigments is shown by Øvre Neådalsvatn (Norway), Ni?né Terianske Pleso, Saanajärvi and Jezero v Ledvici. Except Gossenköllesee (Kamenik et al. 2000, this issue). Significant catchment disturbances are absent in these remote environments, so these increases can be considered to be the result of temperature increase or atmospheric nutrient pollution. Carotenoids belonging to sulphur anaerobic photosynthetic bacteria of the green and red groups (Chlorobiaceae and Chromatiaceae) were found in three lakes, i.e. Jezero v Ledvici, Hagelseewli and Gossenköllesee, implying that these lakes experienced seasonal anoxia in their bottom waters with strong stratification.
SourceJournal of limnology (Testo stamp.) 59, pp. 15–28
Keywordsalpine lakealgal pigment www
JournalJournal of limnology (Testo stamp.)
EditorIstituto per lo Studio degli Ecosistemi., Verbania Pallanza, Italia
Year2000
TypeArticolo in rivista
AuthorsLami, Andrea; Guilizzoni, Piero; Marchetto, Aldo
Text467570 2000 ISI Web of Science WOS ZOOR13700030220 alpine lake algal pigment www High resolution analysis of fossil pigments, carbon, nitrogen and sulphur in the sediment of eight European alpine lakes the MOLAR project. Lami, Andrea; Guilizzoni, Piero; Marchetto, Aldo C.N.R. Istituto Italiano di Idrobiologia, Largo Tonolli 50, 28922 Verbania Pallanza, Italy A palaeoenvironmental reconstruction for the past 2 3 centuries of eight remote sites from northern to southern Europe was based on a number of palaeolimnological proxies, especially fossil pigments. Most of the lakes studied are located above the timberline and a great effort centred on the creation and analysis of a data sets of sedimentary records. A chronology for the last century was based on radiometric techniques 210Pb, 241Am 137Cs . The accumulation rate of recent sediment was found to vary from 0.041 cm y 1 Lake Saanajarvi, Finland to 0.14 cm y 1 Jezero v Ledvici, Slovenia . During the time span represented by the cores were the major changes in organic carbon and nitrogen in Ni ne Terianske Pleso Slovakia , Redo Spain and Gossenkollesee Austria . Constant increase of these nutrients from AD 1900 onwards was shown in lakes Saanajarvi, Ni ne Terianske Pleso and Hagelseewli Switzerland . No common trends in sulphur concentrations was evident. There is evidence of an atmospheric input of sulphur in Hagelseewli. This lake shows the highest concentrations, 10 fold higher at surface than the other lakes ca 6% d.m. . A decrease of S during very recent times is clearly shown by the cores from Redo and Hagelseewli this might be related to the reduction in the atmospheric loading the matching of the atmospheric and sedimentary sulphur trends favours this hypothesis . Concentrations of total pigments and HPLC single carotenoids and chlorophylls showed marked fluctuations throughout the cores of all lakes. High pre AD 1800 pigment concentrations were detected in Ni ne Terianske Pleso, Redo, Hagelseewli and Gossenkollesee. During the last ca 50 years an increase in productivity inferred from fossil pigments is shown by Øvre Neådalsvatn Norway , Ni ne Terianske Pleso, Saanajarvi and Jezero v Ledvici. Except Gossenkollesee Kamenik et al. 2000, this issue . Significant catchment disturbances are absent in these remote environments, so these increases can be considered to be the result of temperature increase or atmospheric nutrient pollution. Carotenoids belonging to sulphur anaerobic photosynthetic bacteria of the green and red groups Chlorobiaceae and Chromatiaceae were found in three lakes, i.e. Jezero v Ledvici, Hagelseewli and Gossenkollesee, implying that these lakes experienced seasonal anoxia in their bottom waters with strong stratification. 59 Published version Articolo in rivista Istituto per lo Studio degli Ecosistemi. 1129 5767 Journal of limnology Testo stamp. Journal of limnology Testo stamp. J. limnol. Testo stamp. Journal of limnology. Testo stamp. piero.guilizzoni GUILIZZONI PIERO aldo.marchetto MARCHETTO ALDO andrea.lami LAMI ANDREA