Author(s): P. Rosén | R. Bindler | T. Korsman | T. Mighall | K. Bishop
Journal: Biogeosciences Discussions
ISSN 1810-6277
Volume: 8;
Issue: 2;
Start page: 2439;
Date: 2011;
VIEW PDF
DOWNLOAD PDF 
Original page
ABSTRACT
Lake Lysevatten has experienced both acidification and recent changes in the amount of lake water organic carbon (TOC) over which is causing concern across Europe and North America. A range of paleolimnological tools – diatom inferred pH, inferred lake water TOC from visible-near-infrared spectroscopy (VNIRS), multi-element geochemistry and pollen analysis, combined with geochemical modeling were used to reconstruct the lake's chemistry and surroundings back to the most recent deglaciation 12 500 years ago. The results reveal that the recent anthropogenic impacts are similar in magnitude to the long-term variation driven by natural catchment changes and early agricultural land use occurring over centuries and millennia. The combined reconstruction of both lake water TOC and lithogenic element delivery can explain the major changes in lake-water pH and modeled acid neutralizing capacity during the past 12 500 years. The results raise important questions regarding what precisely comprises ''reference'' conditions (i.e., free from human impacts) as encapsulated in the European Water Framework Directive.
Journal: Biogeosciences Discussions
ISSN 1810-6277
Volume: 8;
Issue: 2;
Start page: 2439;
Date: 2011;
VIEW PDF
DOWNLOAD PDF Original pageABSTRACT
Lake Lysevatten has experienced both acidification and recent changes in the amount of lake water organic carbon (TOC) over which is causing concern across Europe and North America. A range of paleolimnological tools – diatom inferred pH, inferred lake water TOC from visible-near-infrared spectroscopy (VNIRS), multi-element geochemistry and pollen analysis, combined with geochemical modeling were used to reconstruct the lake's chemistry and surroundings back to the most recent deglaciation 12 500 years ago. The results reveal that the recent anthropogenic impacts are similar in magnitude to the long-term variation driven by natural catchment changes and early agricultural land use occurring over centuries and millennia. The combined reconstruction of both lake water TOC and lithogenic element delivery can explain the major changes in lake-water pH and modeled acid neutralizing capacity during the past 12 500 years. The results raise important questions regarding what precisely comprises ''reference'' conditions (i.e., free from human impacts) as encapsulated in the European Water Framework Directive.
