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Grasslands have deep soils that are very nutrient rich because of
the large amount of plant tissue ('biomass') that dies off and is
added to the soil through decomposition every year. This is why
grassland is often converted into farmland, which has been the case
for most grassland in Ontario.
Often
grassland soil contains a large proportion of clay, which retains
moisture better than sandy soils so that plants growing there can
put on a great deal of growth in the spring when there is more rain.
Grasslands occur where there is less rain than many other ecosystems
in the summer and fall (true prairie is adapted to conditions where
evaporation exceeds precipitation).
Plants
living in grasslands must be adapted to taking advantage of spring
rains to grow and also to tolerating dry summer conditions (drought).
Grasses have very deep and extensive root systems that can reach
down to get water and they lose less water through their leaves
than many other plant types. Grasslands are good at using winter
snow as insulation. Because there are so many plants the snow gets
trapped amongst the leaves and stems. This snow cover protects the
plants and also provides water in spring when the snow melts.
Grasses
in snow. Photo from Konza Prairie Biological Station, Kansas
State University.
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