The Vegetation of the Wabag Region, New Guinea Highlands: A Numerical Study

There are at least three reasons for suspecting the vegetation of the New Guinea Highlands to be changing. Firstly, forest is being actively cut down by the New Guineans to make gardens and it has even been suggested (Robbins 1960) that almost all the non-forest (i.e. vegetation other than forest) is anthropogenic. Secondly, there is geomorphological evidence of a lower snowline formerly in New Guinea (Dozy 1937; Reiner 1960; Bik 1967) and the vegetation may therefore have been influenced by long-term climatic changes. Thirdly, New Guinea is subject to tectonic disturbance and volcanic activity (Taylor 1957), which may have had vegetational repercussions. Previous ecological work in the Highlands has been mostly restricted to general ecological surveys (e.g. Robbins 1958; Robbins & Pullen 1965) and to more detailed studies of small areas (Walker 1966, 1968). The present paper reports mainly random sampling of all vegetation within the Wabag region, including the 'montane' rain forest, and analysis of the data by computer techniques for classification and ordination. This contrasts with recent numerical analyses of rain forest (Ashton 1964; Webb et al. 1967a, b; Greig-Smith, Austin & Whitmore 1967) which have all been carried out on data collected from subjectively sited plots in lowland forest.