Question
Justify that lichens are the pioneer organisms.

Answer

Lichens are the pioneer organisms in the new terrains which colonise bare rocks, mountains and cliffs. They corrode the rocks and accumulate a certain amount of minerals and organic matter. The plants like mossess and grasses appear later in succession, utilising the first soil formed by lichens. Lichens thus, can convert a barren area into one that can support vegetation.

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