title: Effects of reduced summer precipitation on productivity and forage quality of floodplain meadows at the Elbe and the Rhine River.
abstract: BACKGROUND
  Floodplain meadows along rivers are semi-natural habitats and depend on regular land use. When used non-intensively, they offer suitable habitats for many plant species including rare ones. Floodplains are hydrologically dynamic ecosystems with both periods of flooding and of dry conditions. In German floodplains, dry periods may increase due to reduced summer precipitation as projected by climate change scenarios. Against this background, the question arises, how the forage quantity and quality of these meadows might change in future.
  
  
  METHODS
  We report results of two field trials that investigated effects of experimentally reduced summer precipitation on hay quantity and quality of floodplain meadows at the Rhine River (2011-2012) and at two Elbe tributaries (2009-2011). We measured annual yield, the amount of hay biomass, and contents of crude protein, crude fibre, energy, fructan, nitrogen, phosphorus, and potassium.
  
  
  RESULTS
  The annual yield decreased under precipitation reduction at the Rhine River. This was due to reduced productivity in the second cut hay at the Rhine River in which, interestingly, the contents of nitrogen and crude protein increased. The first cut at the Rhine River was unaffected by the treatments. At the Elbe tributaries, the annual yield and the hay quantity and quality of both cuts were only marginally affected by the treatments.
  
  
  CONCLUSIONS
  We conclude that the yield of floodplain meadows may become less reliable in future since the annual yield decreased under precipitation reduction at the Rhine River. However, the first and agriculturally more important cut was almost unaffected by the precipitation reduction, which is probably due to sufficient soil moisture from winter/spring. As long as future water levels of the rivers will not decrease during spring, at least the use of the hay from the first cut of floodplain meadows appears reliable under climate change.
authors.affiliation: Biocenter Klein Flottbek, University of Hamburg, Hamburg, Germany; Institute of Landscape Ecology and Resource Management, Research Centre for Biosystems, Land Use and Nutrition (IFZ), Justus Liebig University Giessen, Giessen, Germany.
authors.forename: Kristin
authors.initials: K
authors.lastname: Ludewig
authors.affiliation: Institute of Landscape Ecology and Resource Management, Research Centre for Biosystems, Land Use and Nutrition (IFZ), Justus Liebig University Giessen, Giessen, Germany.
authors.forename: Tobias W
authors.initials: TW
authors.lastname: Donath
authors.affiliation: Institute of Landscape Ecology and Resource Management, Research Centre for Biosystems, Land Use and Nutrition (IFZ), Justus Liebig University Giessen, Giessen, Germany.
authors.forename: Bianka
authors.initials: B
authors.lastname: Zelle
authors.affiliation: Institute of Landscape Ecology and Resource Management, Research Centre for Biosystems, Land Use and Nutrition (IFZ), Justus Liebig University Giessen, Giessen, Germany.
authors.forename: R Lutz
authors.initials: RL
authors.lastname: Eckstein
authors.affiliation: Bundesanstalt für Gewässerkunde (BfG), Koblenz, Germany.
authors.forename: Eva
authors.initials: E
authors.lastname: Mosner
authors.affiliation: Institute of Landscape Ecology and Resource Management, Research Centre for Biosystems, Land Use and Nutrition (IFZ), Justus Liebig University Giessen, Giessen, Germany.
authors.forename: Annette
authors.initials: A
authors.lastname: Otte
authors.affiliation: Biocenter Klein Flottbek, University of Hamburg, Hamburg, Germany.
authors.forename: Kai
authors.initials: K
authors.lastname: Jensen
mesh_terms: D000222:Adaptation, Physiological; D018533:Biomass; D005858:Germany; D065948:Grassland; D063245:Plant Development; D011891:Rain; D045483:Rivers; D012621:Seasons