Electronic supplementary Table 1: Critical gaps in our knowledge of alpine seed and seedling ecology. Filling these gaps will help us to
understand and predict the effect of warming and reduction of snow cover on alpine plant regeneration by seed. These questions need to be
approached at different scales: both between species comparisons and comparisons between populations of the same species, particularly from
contrasting microhabitats (e.g low land versus high elevation; snowbeds versus fellfields; wet versus dry alpine microenvironments). The
approaches recommended here have been applied previously in other ecosystems, not necessarily in alpine areas.
Critical questions
a.
1. Seed production and predispersal and dispersal effects
b.
c.
Will the new thermal conditions during seed development have
carry-over effects on seeds (size and germination) and seedling
performance (growth and survival)?
Will the new thermal conditions during seed development have
carry-over effects on seed longevity?
Will climate change interfere on seed dispersal?
Recommended methodology
a.
b.
c.
2.
Soil seed bank
3.
Germination phenology
4.
Seedling survival and
establishment
Will warming, coupled with increases in freeze/thaw cycles,
interfere with:
a. viability
b. longevity
c. predation
d. germination
of seeds from the soil seed bank?
a. How might warming and altered frequency of subzero
temperatures interfere with germination phenology? Will these
factors advance, delay, increase or decrease germination?
a. How well can seedlings of different species tolerate freezing
and heating events?
b. Does seedling thermo-tolerance differ depending on
germination strategy of species?
c. Will shifts in germination phenology move seedlings out of
their physiological tolerances?
a.
b.
c.
d.
a.
Exposing plants to simulated climate change conditions
and evaluating its effect on seed size germination and
seedling performance (Klady et al. 2011)
Controlled aging experiments on seeds produced under
contrasting (cold, warm) paternal conditions (Kochanek et
al. 2010; Mondoni et al. 2014b)
Modelling seed dispersal under current and future climate
(Engler & Guisan 2009; Mokany et al. 2014)
Exposure of seeds at different moisture content to subzero
temperatures (Hawkins et al. 2003; Marcante et al. 2012)
Controlled aging experiments (Long et al. 2008)
Soil and seeds reciprocal transplant along the elevational
gradient (Brown & Vellend 2014)
Ex situ germination of soil seed bank samples mimicking
alpine future soil temperatures (Venn & Morgan 2010) or
In situ seed burial experiments (Cavieres & Arroyo 2001).
Exposure of seeds to conditions that mimic soil warming
and freezing events (Mondoni et al. 2012; Hoyle et al.
2013)
a. Expose seedlings to freezing and heating events and
monitor survival or damage to photosynthetic apparatus
(Buchner & Neuner 2003; Shevtsova et al. 2009; SierraAlmeida & Cavieres 2012; Briceño et al. 2014)
b-c. Compare the tolerance to freezing and heating events of
seedlings that differ in germination strategies (e.g seedlings that
emerge in summer versus seedlings that emerge in winter under
snow)