Modern pollen rain

• Main Authors: M. S. Mcglone, C. D. Meurk
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Campbell Island; modern pollen rain; pollen dispersal; pollen representation; subantarctic islands; New Zealand; Auckland Island; Tundra
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.376.2999; http://www.newzealandecology.org/nzje/free_issues/NZJEcol24_2_181.pdf

Abstract: A modern pollen-vegetation data set of 46 samples is presented from subantarctic Campbell Island, 600 km south of the New Zealand mainland. The sampled vegetation includes all major community types: maritime turf and grassland, sedge flushes, dwarf forest, scrub, cushion bog, tussock grassland, and high altitude graminoid turfs and tundra. Macrophyllous forbs- characteristic plants of subantarctic islands- are common throughout. Most taxa have highly restricted pollen dispersal, largely due to the short stature of the vegetation and the high proportion of insect-pollinated species. Percentages of pollen or spores of the dominant taxa have a significant positive correlation with the percent vegetation cover of the corresponding species, the exceptions being the widespread ferns Polystichum vestitum and Blechnum spp., and the ubiquitous macrophyllous forb, Bulbinella rossii. The relationship between the vegetation cover of a given taxon and its pollen representation was usually not strong enough to give confidence in a quantitative reconstruction based on pollen frequency alone. However, the broad vegetation groupings have characteristic pollen and spore spectra clearly related to the abundance of their dominant plant species. Detrended correspondence analysis of the pollen spectra grouped most sites according to their source vegetation type and generated a pattern similar to that of vegetation data analysed in a similar fashion in previous studies of the island. This study, together with recent work on Auckland Island pollen and spore representation, has resulted in a combined modern palynological data base of more than 100 sites for the New Zealand subantarctic islands.