Plant diversity and productivity experiments in European grasslands

At eight European field sites, the impact of Loss of plant diversity on pri mary productivity was simulated by synthesizing grassland communities with different numbers of plant species. Results differed in detail at each Loca tion, but there was an overall Log-Linear reduction of average aboveground biomass with Loss of species. For a given number of species, communities wi th fewer functional groups were Less productive. These diversity effects oc curred along with differences associated with species composition and geogr aphic Location. Niche complementarity and positive species interactions app ear to play a role in generating diversity-productivity relationships withi n sites in addition to sampling from the species pool.