Ranges of woody plant species and ferns on forested elevational gradients on Aotea-Great Barrier Island, New Zealand: the role of zones of permanent and temporary establishment

The arrangement of plant species along elevational gradients is prominent in the debate between individualistic versus community-unit concepts in plant ecology. We obtained elevational ranges (upper and lower elevation limits) for woody species and ferns on the three highest mountains on Aotea (Great Barrier Island), Aotearoa-New Zealand. These data allowed potential species composition to be obtained for any elevation and were analysed using regression, ordination, and classification. Both woody plants and ferns demonstrated linear declines in richness with increasing elevation.