Biogeography and Forest Biodiversity in New Zealand

Authors: John Ogden
Publication: New Zealand Journal of Forestry, Volume N.Z.J.For. 1997, Issue N.Z.J.For. 42(3) 1997, pp 8-14, Nov 1997
Publisher: New Zealand Institute of Forestry

Abstract: The concept of biodiversity is scale dependent. Biogeography is concerned mainly with explaining the larger scale patterns — the origins of the New Zealand flora and the regional patterns of biodiversity within the country (gamma-diversity). Geological and climatic history are important at these scales. Altitudinal gradients illustrate variation at the landscape level (beta-diversity). The conservation of landscape processes is important for maintaining high biodiversity and ecosystem 'services'. Ecologists cannot yet explain differences in diversity at the community scale (alpha-diversity), but arguably the disturbance regime is a key factor. A case study, comparing kauri (Agathis australis) and beech (Nothofagus solandri ) forests, is outlined. If the indigenous conservation strategy, and operational exotic forestry, are to emphasise the sustainability of indigenous biodiversity, then the spatial and temporal scale effects which determine it must be explicitly addressed.