Climate change will lead to changes in precipitation patterns and amounts. Water is an important factor in controlling biological processes, and the changes in precipitation patterns are likely to affect the functioning of terrestrial ecosystems in the future. In connection to the major CLIMAITE experiment a series of water-experiments can be carried out and the effects on ecosystem processes can be investigated.

In order to study changes in precipitation and the specific control of water on the processes, small plots will be established in the area but outside the experimental plots to carry out experiments with addition or removal of precipitation. The experiments can include water addition, drought/rewetting and changes in precipitation patterns and projects could deal with:

1)      Carbon sequestration and soil respiration – carbon sequestration by plant assimilation of carbon can be measured by combining ecosystem respiration and soil respiration in the plots, harvest of biomass etc. Special attention can be given to periods of changing water conditions (e.g. drying, drought and rewetting after drought). This can be combined with measurements of organic carbon export with soil water.

2)      Plant performance and nutrient allocation – water may potentially change the growth of plants and their nutrient content, which may change species composition and affect herbivores and decomposition. Changes in current plant production can be measured by pinpoint analysis. Condensed tannin and nitrogen and phosphorus (nutrient) concentration in leaves may be followed to reveal allocation of nutrients to growth or defence compounds. NIRS (Near Infra Red Spectrometry) analysis is also a possible tool.

3)      Microbial community changes – soil samples can be collected and C/N dynamics assessed by extraction, microbial biomass can be estimated and changes in microbial community function can be assessed by PLFA measurements. Also, studies of changes in mycorrhizal fungal colonization of roots (i.e plant-fungus symbiosis) are possible.

4)      ‘Soil soup’ – soil chemistry with focus on organic compounds. Our knowledge of the chemical composition of DON and DOC (dissolved organic carbon and organic nitrogen) is very limited. Soil samples can be extracted and analyzed for the mixed DON and DOC and for specific organic compounds such as proteins, amino acids (by HPLC) and larger phenolic compounds with NMR-spectroscopy.

Contact (More contact info - press here):

1) Claus Beier, Risø. claus.beier@risoe.dk; Per Ambus, Risø, per.ambus@risoe.dk

2) Inger K. Schmidt, KVL, iks@kvl.dk, Anders Michelsen, KU, andersm@bi.ku.dk

3) Anders Prieme, KU, andersp@bi.ku.dk; Anders Michelsen, KU, andersm@bi.ku.dk; Louise Andresen, KU, louisea@bi.ku.dk

4) Louise Andresen, KU, louisea@bi.ku.dk; Claus Beier, Risø. claus.beier@risoe.dk