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Ecosystems — BIOLOGY STD 12 Science — Question

Rajasthan BoardEnglish MediumSTD 12 ScienceBIOLOGYEcosystems4 Marks
Question
Explain how xerarch succession progresses from serie to mesic condition and forms a stable climax community. You may use a flow chart.
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Answer

Xerarch succession:

  1. In the primary xerarch succession, lichens are the pioneer species; they secrete acids to dissolve the rock, facilitating weathering and soil formation.
  2. With formation of soil, small plants like bryophytes occupy the area.
  3. They are succeeded by bigger plants over a long period of time. After several more seral stages, a stable climax forest community is formed.
  4. The climax community remains stable as long as the environment remains unchanged.
  5. The xeric habitat is changed into a mesic habitat.

 

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