Data from: Biodiversity-ecosystem functioning relationships in a long-term non-weeded field experiment

Many grassland biodiversity experiments show a positive relationship
between biodiversity and ecosystem functioning, however, in most these
experiments plant communities are established by sowing and natural
colonization is prevented by selective weeding of non-sown species. During
ecosystem restoration, for example on abandoned fields, plant communities
start on bare soil, and diversity is often manipulated in a single sowing
event. How such initial plant diversity manipulations influence plant
biodiversity development and ecosystem functioning is not well understood.
We examined how relationships between taxonomic and functional diversity,
biomass production and stability develop over 16 years in non-weeded plots
sown with 15 species, 4 species, or that were not sown. We found that sown
plant communities become functionally similar to unsown, naturally
colonized plant communities. However, initial sowing treatments had
long-lasting effects on species composition and taxonomic diversity. We
found only few relationships between biomass production, or stability in
biomass production, and functional or taxonomic diversity, and the ones we
observed were negative. In addition, the cover of dominant plant species
was positively related to biomass production and stability. We conclude
that effects of introducing plant species at the start of secondary
succession can persist for a long time, and that in secondary succession
communities with natural plant species dynamics diversity-functioning
relationships can be weak or negative. Moreover, our findings indicate
that in systems where natural colonization of species is allowed effects
of plant dominance may underlie diversity-functioning relationships.