Impact of tephra fall and environmental change: a 1000 year record from Matakana Island, Bay of Plenty, North Island, New Zealand.

Abstract

Palynological evidence was used to determine the development of vegetation communities on Matakana Island, North Island, New Zealand, over the last 1000 radiocarbon years. The pollen record indicates that changes occurred in the vegetation immediately following fallout deposition of the Kaharoa Tephra approximately 100 km from source at c. 665 years BP. Such changes may be a direct response to the impact of tephra fall, although the possibility of anthropogenic disturbance cannot be discounted. As a result of the eruption some taxa (Leucopogon fasciculatus and Tupeia antarctica) became at least temporarily extinct from the area. Two phases of anthropogenic influence on the environment are recorded in the pollen record: Polynesian, followed by European inhabitation of the island, giving a detailed history of human influence in the area for the millennium.