BIO120H1 Lecture Notes - Lecture 11: Montane Ecosystems, Soil, Seed Dispersal
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Lecture 11: Putting things together: Species interactions in subalpine meadows
· Erythronium grandiflorum (glacier lily)(zoom in)
o Observed the most where the soil surface is very rocky.
o Half part of the plant grows in the soil, during most of the time, all parts
are underground, grows up when flowering.
o Nutrients stored in the bulbs.
Primary seed dispersal distance experiment
· Mark seeds in fruits with fluorescent powders, lay out fabric sprayed with
· Result: dispersal distance about 20cm; pathetic!
· Glacier lily does not have elaiosome.
o Doesn’t have anything to do with growth, extremely nutritious, attracts antsàprovide a
Seed germination experiments
· Plant the seed in 4 treatment combination:
o Buried, organic soilà live!
o Exposed, organic soilàdied!
o Buried, gravel soilàdied!
o Exposed, gravel soilàdied!
· Long-lived, iteroparous; grows as a “vegetative” plants for years before flowering.
o At least 6-7 years to grow
· Resource storage organ is underground corm
· Seeds subject to desiccation unless in moist conditions
· Seed dispersal distance minimal
What do the experiments suggest about distribution?
· Desiccation: should find more plants on the deep soil, less plant on the shallow soil (but we see
· Weak dispersal: should find most seeding near flowering plants (expect to find those)
· Need to gather quantitative date on plant abundance and environmental factors
Set up study plot, 16X16 grid of 2X2m squares; measure variables in each square; make maps
· Factors measuring
o Flowering plants (count)
o Vegetative plants (count)
o Seedlings (subsample)
o Soil moisture
o Predation risk
§ Attacked underground by pocket gopher; eat corm
§ Digging specialist; claws and teeth
§ Huge cheek pouches to store food
· Quantified by the amount of soil they pushed up to make tunnel
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