Effects of fragmentation at fine scale in Mediterranean mountain grasslands

European mountain grasslands suffer a process of abandonment and are colonized by shrubs and forest. This makes a fragmentation at fine scale where a matrix forest surrounds the grassland fragments. Multiple studies have been realized about grassland fragmentation but in anthropic matrix like crops. There is no knowledge about the effect of fragmentation on the abandoned grasslands where the isolation can be minor but not the environmental change due to the surrounding forest in the smallest fragments. In this work, we studied abandoned Mediterranean mountain grasslands in an oak forest matrix. We surveyed the grassland communities and their soil properties in multiple fragments of different sizes and isolation. We classified the communities into different functional groups and calculated landscape variables of fragmentation. Then, we analysed the effect of the fragmentation on the richness of the functional groups and the grassland community. The results show that the fragmentation does not have any effect on the grasslands except on the communities in the extreme gradient of the vegetation succession, the annuals and fringe forest communities. The landscape configuration does not have effects on the grasslands. The smallest grasslands favoured the herbaceous fringe forest and the decrease of the annuals, due to higher amounts of soil organic carbon and less light availability and wetter conditions. Annual grasslands are more abundant in bigger fragments with drier conditions. The connectivity among fragments is not a problem for the grassland communities at fine scale. The typical grassland species show that they remain even in the smallest fragments although in theses the community is more similar to the forest fringe.