The ecology of lowland totara in South Island, New Zealand [article]

R. L. Ebbett, University Of Canterbury
Historically, lowland totara was a common forest tree throughout much of lowland New Zealand but is now confined to small, mainly protected, areas usually as the dominant species in mixed podocarp forest with matai and kahikatea. Lowland podocarp forest has suffered the most extensive reduction of all New Zealand forest types, with only circa 1% of the original forest cover remaining. The lowland totara dominated stands remaining therefore represent an highly fragmented population with
more » ... ation with relatively few individuals, making the collection of large data sets difficult. Sample sizes are small in some stands due to the limited area of to tara dominated forest (circa 1 hectare). The present study aims to describe the natural extent of lowland totara forest, document its reduction and current status, and to provide for the long-term survival of this species in the now fragmented forest environment. Literature relating to the ecology of Podocarpus totara is reviewed with respect to vegetative morphology and growth, reproductive biology, timber properties and· utilisation, and population dynamics. The ecological niche of lowland totara is defined, examining site characteristics and soil type. The distribution of lowland totara dominated stands is a function of several interlinked site characteristics such as climate, landform, drainage, disturbance regime, soil type, and altitude. Lowland totara appears to be confined to semi-fertile or fertile soils which are the result of landform and disturbance e.g. flood events on a river plain. Stand descriptions identify lowland totara forest as ranging from pure totara, to totara - matai, to totara - matai - kahikatea, to dense mixedpodocarps. The relative proportions of totara, matai, and kahikatea appear to be due to edaphic features such as fertility and drainage. In dense mixed podocarp forest, totara is confined in small populations to optimal sites such as terraces and ridges. The podocarps have differing nutrient, light, and disturbance regime requirements and these factors w [...]
doi:10.26021/1645 fatcat:ljkjfjqsljepjmyrfvkcpo3xwa