A meta-analysis on the effects of climate change on the yield and quality of European pastures

As has been widely reported, climate change will be felt throughout Europe, though effects are likely to vary dramatically across European regions. While all areas are expected to experience elevated atmospheric CO2 concentrations (up arrow C) and higher temperatures (up arrow T), the north east will get considerably wetter (up arrow W) while the south much drier (down arrow W). It is likely that these changes will have an impact on pastures and consequently on grazing livestock. This study aims to evaluate the expected changes to pasture yield and quality caused by up arrow C, up arrow T, up arrow W and down arrow W across the different European regions and across different plant functional groups (PFGs). Data was collected from 143 studies giving a total of 998 observations. Mixed models were used to estimate expected changes in above ground dry weight (AGDW) and nitrogen (N) concentrations and were implemented using Markov Chain Monte Carlo simulations. The results showed an increase in AGDW under up arrow C, particularly for shrubs (+71.6%), though this is likely to be accompanied by a reduction in N concentrations (-4.8%). up arrow T will increase yields in Alpine and northern areas (+82.6%), though other regions will experience little change or else decreases. up arrow T will also reduce N concentrations, especially for shrubs (-13.6%) and forbs (-18.5%). down arrow W will decrease AGDW for all regions and PFGs, though will increase N concentrations (+11.7%). Under up arrow W there was a 33.8% increase in AGDW. While there is a need for further research to get a more complete picture of future pasture conditions, this analysis provides a general overview of expected changes and thus can help European farmers prepare to adapt their systems to meet the challenges presented by a changing climate.