Data from: Climate variability and community stability in Mediterranean shrublands: the role of functional diversity and soil environment

1.Understanding how different factors mediate the resistance of
communities to climatic variability is a question of considerable
ecological interest that remains mostly unresolved. This is particularly
remarkable to improve predictions about the impact of climate change on
vegetation. 2.Here we used a trait-based approach to analyse the
sensitivity to climatic variability over nine years of 19 Mediterranean
shrubland communities located in southwest Spain. We evaluated the role of
functional diversity and soil environment as drivers of community
stability (assessed as changes in plant cover, species diversity and
composition). 3.The studied shrubland communities were strongly sensitive
to inter-annual variability in climate. First, colder and drier conditions
caused remarkable decreases in total plant cover but increased functional
diversity, likely because the reduction of plant cover after harsh
climatic conditions promoted the expansion of functionally dissimilar
species in the new open microsites; although communities returned to their
initial values of plant cover after nine years, changes in functional
diversity and structure persisted over time. Second, drier and colder
conditions favoured the predominance of shrubs with a conservative
resource-use strategy (i.e. with higher dry matter content in leaves,
stems and roots), bigger seeds and a more efficient use of water. 4.The
most functionally diverse communities were the most stable over time in
terms of species diversity, likely because a higher number of functionally
dissimilar species allowed compensatory dynamics among them. 5.Communities
inhabiting more acidic and resource-limited environments were less
variable over time, probably because they were mainly constituted by
slow-growth, stress-tolerant species that are potentially better adapted
to harsh climatic conditions. 6.Synthesis: This study highlights the
utility of a trait-based approach to evaluate how plant communities
respond to climatic variability. We could infer that the increased
frequency of extreme climatic events predicted by climatic models will
alter the functional structure of shrubland communities, with potential
repercussions for ecosystem functioning. Our results also provide new
insights into the role of functional diversity and soil environment as
buffers of the climate impact on woody communities, as well as potentially
useful information to be applied in ecologically-based management and
restoration strategies.