32 10 Lanzarote is a volcanic island in the Atlantic Ocean. It lies near the coast of West Africa. The photograph shows lichens growing on volcanic rock in Lanzarote. Lichens are organisms composed of a fungus and algae living together. Lichens colonise bare rock. (a) Explain how colonisation of bare rock by lichens can result in succession over long periods of time. 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Turn over 33 (b) Devise an investigation to show how the lichen distribution is affected by a named abiotic factor. 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(Total for Question 10 = 10 marks)