Data from: Seed dormancy explains plant response to mass mortality events

Mass mortality events (MMEs) are large-scale, rapid die-offs resulting in
extreme inputs of carrion biomass. Recent work demonstrates the effects of
increasing carrion biomass on plant communities modulated by vertebrate
scavengers and herbivores. However, the mechanisms underlying plant
response to MMEs remain unclear. We hypothesized that carrion
decomposition would interact with vertebrate herbivory and scavenging to
generate distinct ecological filters on plants grouped by three seed
dormancy classes (no dormancy, physiological dormancy, and physical
dormancy). We designed a replicated field experiment crossing two levels
of carrion biomass (~30 kg and ~360 kg) with three levels of vertebrate
exclusion (open/no exclusion, scavenger exclusion, and herbivore
exclusion) to quantify plant extirpation and colonization, plant
performance, and the response of simulated seed bank and seed rain. We
measured carrion decomposition rate, plant tissue nutrients (N, P, and K),
seed survival, plant height, flower production, and plant community
changes over 3 years. Carrion biomass levels associated with mass
mortality increased plant tissue nutrients and plant extirpation and
decreased seed bank survival, likely promoting plant colonization from
seed rain. Vertebrate exclusion determined colonization probability in
different ways, depending on seed dormancy classes. Vertebrate scavenger
exclusion delayed decomposition, and the resulting environment favored the
colonization of plants with impermeable seed coats (physical dormancy). In
contrast, vertebrate herbivore exclusion promoted rapid germinators (no
dormancy) that arrived as seed rain and quickly capitalized on the
nutrient-rich exposed soil. With both functional roles intact (open/no
exclusion), vertebrate scavenging ameliorated the negative effects of
decomposition on seeds and plants, and selective herbivory on
nutrient-rich plant tissue reduced overall plant height and flower
production. The activity of both functional roles favored plants of the
dominant physiological seed dormancy class and those with physical
dormancy. Our results suggest that seed response to carrion decomposition
and vertebrate functional activity can inform plant community response to
MMEs.