HOLOCENE POLLEN STRATIGRAPHY AND SEDIMENTATION, WELLINGTON HARBOR, NEW-ZEALAND

Pollen and spore spectra obtained from within, and around, Wellington Harbour provide a record of climate and land-use change from early Hol ocene to the present day. Samples of four cores from Wellington Harbou r show that Nothofagus group pollen has increased six-fold relative to Dacrydium cupressinum since c. 10 000 years ago. From A.D. 1840 there is evidence of land clearance and the introduction of exotic species by European settlers. Historical records show that 80-90?% of the nati ve forest was replaced with grassland between A.D. 1840 and 1900, a fa r greater land-use change than that indicated by the pollen record. Pa lynomorphs from the modern harbour floor contain assemblages similar t o those obtained from contemporary forested terrestrial sites. Both ar e dominated by Nothofagus group, Dacrydium cupressinum pollen, and fer n spores. In contrast, assemblages from non-forested areas are dominat ed by the local pollen source and contain considerable grass and shrub spores. There is a uniform, mixed nature to the palynomorph spectra i n Wellington Harbour. It is concluded that almost all pollen entering Wellington Harbour does so via the Hutt River from reworked forested p arts of the upper river catchment.