PLANT SUCCESSION ON RECENT VOLCANOES IN PAPUA
BY B . W. TAYLOR*
(WithPlate 14 and two Figures in the Text)
Within the territory of Papua, part of the island of New Guinea, only three volcanoes are known to be active. These volcanoes, Mt. Lamington, Waiowa Volcano and Mt. Victory, are all situated within 30 km. of the north coast, in the Northern Division of Papua.
Climatically, the Northern Division is part of the wet tropics with a mean tem- perature at sea-level of 27" C. and a rainfall ranging from 2800 mm. to over 3600 mm. There is a yearly 'dry' season but nowhere does the driest month average less than 100 mm. of rain. Typically the area consists of a wide alluvial plain extending from the high central ranges to the sea. This plain is broken in many places by volcanic ranges and cones, the great majority being of Pleistocene age.
The author was able to visit the blast areas of the three volcanoes while taking part in a land resources survey undertaken by a team from the Commonwealth Scientific and ~ndustrkiResearch Organization on behalf of the Administration of Papua and New Guinea. The time available for the investigation of these blast areas was limited, 5 days being spent on Mt. Lamington, in July, 1953, 14 days on Waiowa Volcano and 6 days on Mt. Victory. As a result it is possible to give only an outline of the plant communities present.
Grateful thanks are due to other members of the survey team, particularly Mr.
A. Haantjens who is responsible for most of the information on soils, and to Dr.
D. Hoogland and Mr. J. Saunders who are responsible for the collection numbers
quoted in the text. The full collections of Dr. Hoogland and Mr. Saunders are lodged in the Herbarium Australiense, Canberra, and Department of Forests Herbarium, kae, New Guinea. Duplicates of almost all numbers have been lodged in the fol- lowing herbaria - Leiden, Arnold Arboretum, Grey, Kew, British Museum, Brisbane, U.S. National and Melbourne. Native.nameswere used as an aid to field identification and where quoted in the text these have been followed by (Or) indicating Orokaiva language and (On) Onjob language. Further thanks are due to E. Taylor and J. Thompson, Bureau of Mineral Resources, Canberra, for helpful discussions on vulcanism in the region. The ecological concepts used in this paper follow Beadle and Costin (1952)with some additions from Beard (1955).
Mt. Lamington, 1600 m. high, was believed to be extinct until it erupted in January 1951. The eruption was of the Pelean type and spread a glowing cloud of hot ash with great force over an area of approximately 200 k m . T h i s explosion laid flat
*Land Research and Regional Survey Section, C.S.I.R.O., Canberra, i\ustralia.