ABSTRACT
At present, most grassland biomass is used for beef and dairy farming. However, during the last decades there have been notable changes in grassland use in many regions of the world. Enhanced animal performance with increased milk and meat production has changed ruminant diet composition. On the one hand, the demand for roughage has fallen due to a higher percentage of concentrates in feed and, on the other hand, the yield of grassland is rising due to intensification. There is already a surplus of grassland in many developed countries. The conversion of unused grassland into arable land is often limited by site conditions, economic viability, ecological and climatic considerations, or legislation. Marginal areas with low productivity are usually the first to be abandoned.
