The impact of volcanism on ecosystems in the North Island

The principal volcanic processes that destroy or modify ecosystems are pyroclastic flows (nuees ardentes), acid rains and gases, lateral blasts and pyroclastic surges, debris avalanches and volcanic mudflows (lahars), tephras (from fme ash to coarse pumice or scoria) and lava flows. The role of these processes in ecosystem modification in the North Island is reviewed in combination with reference to available overseas examples and new palynological information from Mt Egmont. The response of ecosystems to these processes is also discussed with particular reference to recovery patterns ascertained from palynological studies in Taranaki.