Ecological Studies of Hawaiian Metrosideros in a Successional Context

摘要

'Ohi'a (Metrosideros polymorpha) is the dominant rain foresttree species in Hawai'i. It has long impressed botanists for its morphologicalvariability and ecological amplitude. The present study has documenteddifferences in the distribution of Metrosideros polymorpha varieties in populationsof 'ohi'a growing on adjacent young and old flows. Pubescent varietiesare present on young volcanic substrates, but tend to be absent from oldersoils in the rain forest zone. The genetic basis for these varieties has beenconfirmed in a common garden experiment. The water relations of pioneerand older forest '6hi'a have been examined and shown to differ, so that thepioneer 'ohi'a tend to be able to maintain turgor at lower relative water contentsthan the glabrous varieties.