FNU - Klimaændringsperspektiv
This project aims to compare the trophic structure and functioning of lowland streams and shallow lakes under temperate and subtropical climates, in relation to land use in the catchments and climatic variability.
Results from previous comparative studies conducted in a series of shallow lakes and streams in temperate (Denmark) and subtropical (Uruguay) regions have shown very interesting patterns, suggesting a much stronger effect of fish communities in the warm climates, under similar environmental conditions.
Another open question is how these interactions change along a gradient of input of organic matter and nutrients, i.e. changes in the area use of the catchments. Results from lakes indicate that there are no major differences between lakes with varying nutrient levels relative to the significant difference generally observed between Denmark and Uruguay (Meerhoff et al., 2007). However, whether this general pattern applies as well to the more open systems still remains to be elucidated, since the previous studies were conducted in a set of pristine, low impact, streams. How these structural differences impact the turnover of organic matter and the general metabolism is yet another subject awaiting clarification. We have introduced continuous measurement sondes in two streams with contrasting land use and one lake in each country, and monitor physico-chemical variables of the water (oxygen, pH, conductivity, turbidity). Simultaneously, we are registering meteorological variables such as precipitation, solar radiation and temperature, to relate the changes in water quantity (discharge) and quality with the climatic variability, along a two-year period.
Puntas del Pantanoso stream, Uruguay, before (top) and after (bottom) a
flooding event. The meteorological station and water pump are located in the
shed built on top of rocks, to prevent damage after floodings. The sonde is
located on top of the stream bed, near the shed.
The main biological characteristics (fish, macroinvertebrates, periphyton, macrophytes) are also studied in each system, and follow-up experiments are also to be conducted along the period to elucidate the role of fish and plants in these trophic interactions. Finally, the importance of catchment characteristics for the input of nutrients and organic matter and the effects of these on the biological structure and interactions, primary production and nutrient turnover will be elucidate via intensive measurements in a series of selected streams and lakes with contrasting land use in the catchments. This project is hitherto the most comprehensive ecosystem study of lakes and streams in temperate and subtropical areas.
The research team involves scientists from Denmark (NERI-AU) and Uruguay (Universidad de la República), and the development of several postgraduate theses (both MSc and PhDs) of students from both countries, supervised in cooperation.
Projektkontakt:
Erik Jeppesen ej@dmu.dk
Brian Kronvang bkr@dmu.dk
Annette Baattrup-Pedersen abp@dmu.dk
Mariana Meerhoff mm@dmu.dk
Projektperiode: January 2009-December 2011
Projektteam:
Opdateret: Maj 2010
Tilknyttede projekter:
2007-2008. Comparative study on the biological structure of lowland streams in Uruguay and Denmark. Responsible: A. Baattrup-Pedersen, E. Jeppesen, M. Meerhoff. Funding: NERI.
2003-2006. The structuring role of macrophytes on trophic dynamics in shallow lakes under a global warming scenario. Responsible: M. Meerhoff. Funding: Danish Research Agency.
Nøglepublikationer:
We have no publications yet from ongoing research, but related publications, from previous connected projects, are:
Jeppesen, E., Meerhoff, M., Holmgren, K., Gonzalez-Bergonsoni, I., Teixeira de Mello, F., Declerk, S., deMeester, L., Søndergaard, M., Lauridsen, T., Bjerring, R., Conde-^Porcuna, J., Reizenstein, M., Mazzeo, N., Frizzera, C.I., Malmquist, H., Balayla, D. 2010. Impacts of global warming on fish community structure and traits in shallow and deep lakes, and potential ecosystem effects. Hydrobiologia, 646:73-90
Teixeira-de Mello, F., Meerhoff, M., Pekcan-Hekim, Z., Jeppesen, E. 2010. Substantial differences in littoral fish community structure and dynamics in subtropical and temperate shallow lakes. Freshwater Biology, 54:1202-1215.
Meerhoff, M., Clemente, J.M., Teixeira de Mello, F., Iglesias, C., Pedersen, A.R., Jeppesen, E. 2007. Can warm climate-related structure of littoral predator assemblies weaken the clear water state in shallow lakes? Global Change Biology, vol. 13, pp. 1888-1897.
Projektteam i afdelingen: Annette Baattrup-Pedersen, Brian Kronvang, Carl Christian Hoffmann, Erik Jeppesen, Esben Kristensen, Frank Landkildehus, Liselotte Sander Johansson, Lone Liboriussen, Niels Bering Ovesen, Torben Linding Lauridsen
Laboranter: Henrik Stenholt, Johnny Nielsen, Karina Jensen, Kirsten Landkildehus Thomsen, Marlene Venø Skjærbæk, Tommy Silberg, Uffe Mensberg
IT: Carsten B. Nielsen
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