Data from: Seed supply, recruitment, and assembly: quantifying relative seed and establishment limitation in a plant community context

There is growing consensus that the relative constraints of seed
limitation and establishment limitation in recruitment strongly influence
abundance patterns in plant communities. Although these constraints have
direct relevance to coexistence, most investigations utilize a seed
addition approach that offers limited insight into these dynamics. Here we
report results of an assembly experiment with annual plant species of
California grasslands to examine how propagule pool characteristics
(dominant species abundance, functional diversity) influence establishment
and seed limitation (density independence and density dependence across a
gradient of seed supply) for each species, and how these constraints
affect community diversity. Species were predominantly co-limited by seed
and establishment constraints, exhibiting saturating recruitment functions
with increased seed supply. Consistent with competition-colonization
trade-off predictions, recruitment constraints often depended on the
degree of seed limitation of the competitive dominant, Brassica nigra;
diversity was greatest in communities where Brassica was seed limited.
Functional similarity within the propagule pool did not affect recruitment
across a range of seed supply; likewise, functional diversity of the
propagule pool was not related to community diversity. We conclude that
seed limitation of the dominant species rather than niche similarity
influences interspecific competition for safe sites and scales up to
affect community-level diversity.