Page 6 - Lesson note-Ecosytem
P. 6
o Hydrach succession takes place in wetter area and the successional series progress from
hydric to the mesic conditions.
o Xerarch succession takes place in dry areas and series progress from xeric to mesic
conditions.
· The species that invade a bare area are called pioneer species. In primary succession on
rocks lichens are pioneer species that secrete acids to dissolve the rock for weathering to
form soil.
· In primary succession in water, the pioneer species are the small phytoplanktons that are
replaced by free floating angiosperms.
· Primary succession is slow process as soil is not available for pioneer species but secondary
succession is comparatively faster due to availability of soil or other nutrients. A climax
community is reached much faster in case of secondary succession.
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