Water stress due to increased intra-annual precipitation variability reduced forage yield but raised forage quality of a temperate grassland

A nitrogen dilution effect (decreased plant nitrogen concentration with increasing shoot biomass) likely influenced the grassland crude protein contents under altered precipitation regimes and might have masked possible effects of precipitation variability on plant nitrogen and therefore on quality of grassland species. Nevertheless, alterations in the plant community composition and plant senescence seem to be the main drivers of forage quality change. Fertilization during drought periods and harvest delay after drought periods were only partially successful as management strategies to sustain forage production in more extreme precipitation regimes of the future. Further strategies need to be developed that acknowledge the shift in plant species compositions as the main driver of changes in forage quality in the face of changing precipitation patterns.