Warming and browning of lakes: consequences for pelagic carbon metabolism and sediment delivery
Författare
Summary, in English
1. Thousands of lakes in the Northern Hemisphere are experiencing a continuous increase in water temperature and colour. While increasing temperature is an effect of climate change, several factors are suggested to drive the increasing water colour, including climate change, altered land use and reversed acidification. 2. In this mesocosm study, we study the effects on pelagic production and sedimentation of organic carbon from a 3 degrees C increase in temperature, a doubling of water colour and a combination of increased temperature and water colour. These manipulations correspond to the predicted development in water colour and temperature in northern temperate systems within the life time of the next generation. 3. The water and plankton communities in the mesocosms were taken from an oligohumic and mesotrophic lake, and the increase in water colour was achieved by the additions of water from a humic lake. The experiment ran from early March to late October. 4. In accordance with our predictions and previous cross-system analyses, net carbon production (NCP) and organic carbon sedimentation decreased in response to increasing water colour. 5. At odds with current theory, NCP and sedimentation increased in heated treatments, as not only respiration but also gross production increased in response to temperature. There were no synergistic effects between warming and browning. 6. These results imply that warming may enhance pelagic delivery of organic carbon to sediments. This could potentially offset a reduction in burial efficiency of organic carbon, which has been projected based on a positive relationship between carbon mineralisation in sediments and temperature.
Avdelning/ar
Publiceringsår
2014
Språk
Engelska
Sidor
325-336
Publikation/Tidskrift/Serie
Freshwater Biology
Volym
59
Issue
2
Dokumenttyp
Artikel i tidskrift
Förlag
Wiley-Blackwell
Ämne
- Ecology
Nyckelord
- brownification
- carbon metabolism
- climate change
- sedimentation
- temperature
Status
Published
Projekt
- MICCS - Molecular Interactions Controlling soil Carbon Sequestration
Forskningsgrupp
- Aquatic Ecology
ISBN/ISSN/Övrigt
- ISSN: 0046-5070