New Zealand isopollen and isochrone maps : an integrative approach to reconstructing the paleoenvironment since the last glacial maximum : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Geography at Massey University, Palmerston North, New Zealand
series of isopollen and isochrone maps for New Zealand since the Last Glacial Maximum (LGM) is presented; these maps suggest likely paleovegetation patterns in New Zealand since the LGM. To the best of my knowledge, they are the first constructed for any region in the Southern Hemisphere. The procedure used to construct the maps was unique in a number of ways. Contouring was predominantly acheived using kriging techniques on a computer package rather than manual contouring, which has been the norm in other regions. An integrative approach was used; marine microfossil data was utilised to derive paleo-sea surface temperatures which, when combined with faunal freezing temperatures, yielded a priori theoretical altitudinal limits for selected taxa to augment the fossil pollen data. Terrestrial macrofossil data was used to evaluate the resultant maps. Paleo-shorelines, also derived from macrofossil studies, are shown. Paleo-shorelines are important in that coastal areas may have served as refugia during, and migration routes after, the LGM. The resultant maps show that an integrative approach was generally successful. The maps give a more holistic view of New Zealand's paleoenvironment than is possible from studying individual fossil pollen diagrams, and some interesting conclusions are reached. The southern limit of continual forest in the late glacial period may have been 2° south of commonly accepted limits. The existence of a Younger Dryas-synchronous cooling in New Zealand is shown to be unlikely from a palynological perspective.