COMPARISON OF FOREST STRUCTURE AND REGENERATION ON BENCH AND STEWART ISLANDS, NEW ZEALAND

摘要: SUMMARY: The absence of introduced browsing animals from Bench Island, located 5 km east Stewart provides the opportunity to compare forest structure and regeneration in these two areas similar vegetation with without animals. population structures main canopy tree species, rata (Metrosideros umbellata), kamahi (Weinmannia racemosa), rimu (Dacrydium cupressinum), are compared. However, on animals, mainly white-tailed deer (Odocoileus virginianus) Australian brush-tailed possum (Trichosurus vulpecula), have drastically reduced abundance subcanopy trees shrubs such as Pseudopanax simplex, P. crassifolius, Fucshia excorticata, Myrsine australis, Schefflera digitata, Coprosma lucida C. foetidissima; ferns Phymatosorus diversifolius, Asplenium bulbiferum herbs like Kirkophytum lyallii likewise been reduced. fern Dicksonia squarrosa is also severely impeded by browsing, generally sparse character understorey Island contrasts sharply nearly continuous cover Island. On more open greatly plants 15-140cm tier results greater species frequencies 0-15 em tier, but pressure impedes their further development. Introduced already significantly altered floristic composition rata-kamahi-rimu forests effects likely be severe future unless animal numbers