European soil seed bank communities across a climate and land-cover gradient

This is the data set used for the publication Buffering effects of soil
seed banks on plant community composition in response to land use and
climate, published in the journal Global Ecology and Biogeography. Aim.
Climate and land use are key determinants of biodiversity, with past and
ongoing changes posing serious threats to global ecosystems. Unlike most
other organism groups, plant species can possess dormant life-history
stages such as soil seed banks, which may help plant communities to resist
or at least postpone the detrimental impact of global changes. This study
investigates the potential for soil seed banks to achieve this. Location.
Europe Time period. 1978 – 2014 Major taxa studied. Flowering plants
Methods. Using a space-for-time/warming approach, we study plant species
richness and composition in the herb layer and the soil seed bank in 2796
community plots from 54 datasets in managed grasslands, forests and
intermediate, successional habitats across a climate gradient. Results.
Soil seed banks held more species than the herb layer, being
compositionally similar across habitats. Species richness was lower in
forests and successional habitats compared to grasslands, with annual
temperature range more important than mean annual temperature for
determining richness. Climate and land use effects were generally less
pronounced when plant community richness included seed bank species
richness, while there was no clear effect of land use and climate on
compositional similarity between the seed bank and the herb layer. Main
conclusions. High seed bank diversity and compositional similarity between
the herb layer and seed bank plant communities may provide a potentially
important functional buffer against the impact of ongoing environmental
changes on plant communities. This capacity could, however, be threatened
by climate warming. Dormant life-history stages can therefore be important
sources of diversity in changing environments, potentially underpinning
already observed time-lags in plant community responses to global change.
However, as soil seed banks themselves appear, albeit less, vulnerable to
the same changes, their potential to buffer change can only be temporary,
and major community shifts may still be expected.