Show simple item record

dc.contributor.authorWillems Nancyen
dc.date.accessioned2009-11-26T03:41:22Z
dc.date.issued1999en
dc.identifier.urihttps://hdl.handle.net/10182/1301
dc.description.abstractAlthough species maintenance in small forest fragments relies on successful regeneration and recruitment, few studies have examined the effects of fragmentation on regeneration processes. New Zealand's podocarp species rely on large disturbance openings operating across a vegetated landscape to stimulate regeneration. Clearance of vegetation that results in small fragments of forest removes regeneration opportunities for podocarps by destroying the intact vegetation mosaic, and as a result may exclude disturbances of the scale necessary for podocarp regeneration. Fragmentation alters the disturbance regime of the landscape, with important implications for the regeneration of podocarps on Banks Peninsula. The four remaining lowland podocarp-hardwood fragments on Banks Peninsula were sampled to determine the structure and regeneration patterns of podocarps and to assess their long term viability. Density, basal area, and size and age class distributions were used to examine current composition, and in conjunction with spatial analysis, to identify past regeneration patterns and infer likely future changes in composition and population structure. Podocarp size and age class structures for three of the four fragments were characteristically even-sized and relatively even-aged (eg; Prumnopitys taxifolia c. 350 to 600 years), with little or no regeneration for approximately the last 200 years (old-growth fragments). Regeneration of the current podocarp canopy in the old-growth fragments may have been stimulated by flooding. The fourth younger fragment showed much more recent regeneration with Prumnopitys taxifolia, Podocarpus totara and Dacrycarpus dacrydioides mostly 80-160 years old, and substantial populations of seedlings and saplings, probably as a result of anthropogenic fire. In the absence of major disturbance the podocarp component in forest fragments on Banks Peninsula is likely to decline with composition shifting towards dominance by hardwood species. There is some evidence to suggest that canopy collapse will stimulate some podocarp regeneration within the fragments, however it appears to be unlikely that podocarps will persist on Banks Peninsula indefinitely within the fragments studied. There is an urgent need for more quantitative research in New Zealand fragmentation literature, and a need for more emphasis on processes. Banks Peninsula offers potential for a more landscape scale approach in forest management, and the maintenance of regenerating scrub in pockets about the Peninsula may offer the regeneration opportunities for podocarps that are lacking within protected fragments. My study took a quantitative approach in examining the effects of forest fragmentation on the demographics of podocarps and compositional change in forest fragments on Banks Peninsula.en
dc.language.isoenen
dc.publisherLincoln Universityen
dc.subjectcompositionen
dc.subjectDacrycarpus dacrydioidesen
dc.subjectdisturbanceen
dc.subjectforest structureen
dc.subjectfragmentsen
dc.subjecthardwooden
dc.subjectpodocarpen
dc.subjectPrumnopitys taxifoliaen
dc.subjectregenerationen
dc.subjectBanks Peninsulaen
dc.subjectPodocarpus totaraen
dc.titleForest structure and regeneration dynamics of podocarp/hardwood forest fragments, Banks Peninsula, New Zealanden
dc.typeThesis
thesis.degree.grantorLincoln Universityen
thesis.degree.levelMastersen
thesis.degree.nameMaster of Applied Scienceen
dc.subject.marsdenFields of Research::300000 Agricultural, Veterinary and Environmental Sciences::300600 Forestry Sciences::300604 Management and environmenten
dc.subject.marsdenFields of Research::300000 Agricultural, Veterinary and Environmental Sciences::300800 Environmental Science::300801 Environmental management and rehabilitationen
lu.contributor.unitLincoln Universityen
pubs.organisational-group/LU
pubs.publication-statusPublisheden


Files in this item

Default Thumbnail
Default Thumbnail

This item appears in the following Collection(s)

Show simple item record