Library Open Repository

Patterned quaking mire at Handspike Point, Macquarie Island

Downloads

Downloads per month over past year

Rich, J (1996) Patterned quaking mire at Handspike Point, Macquarie Island. Papers and Proceedings of the Royal Society of Tasmania, 130 (1). pp. 49-66. ISSN 0080-4703

[img]
Preview
PDF
1996-part1-Rich...pdf | Download (800kB)
Available under University of Tasmania Standard License.

Abstract

Raised mires occur on an emerging marine terrace of Holocene age at Handspike Point, Macquarie
Island, and slope seawards. Ponions
of these mires are characterised by numerous, anastomosing to parallel, low peat ridges, separated
by waterlogged troughs. The resulting patterns arc accentuated by the distinctive rosette
plant Pleurophyllurn hookeri, which grows only on the ridges. Sampling suggests that ridge and
trough patterns persist to at least l.)m depth. Pleurophy/lum colonisation appears to be
a function of the difference in trough: ridge peat bulk density. As chis density ratio
approaches 0.8, waterlogging decreases and Pleurophyllurn vigour is enhanced.
Patterns are oriented at various angles to the present surface slopes, bur roughly parallel ro the
plateau margin and normal to the regional slope of the marine terrace. The divergence between
pattern and local contour orientation results from non-uniform accretion. Patterns at angles to
the contours appear ro provide benefits which include enhanced water-level stability.
The Handspike mires exhibit many characteristics of patterned and non-pancrned peatlands
ubiquitous throughout the Northern
Hemisphere, with particular similarities to eccentric domed mires of the Baltic
region. Vertical accretion is estimated to average
1mm yr-1; lateral accretion appears to be in equilibrium with the emerging marine terrace.

Item Type: Article
Keywords: Royal Society of Tasmania, RST, Van Diemens Land, natural history, science, ecology, taxonomy, botany, zoology, geology, geography, papers & proceedings, Australia, UTAS Library
Journal or Publication Title: Papers and Proceedings of the Royal Society of Tasmania
Page Range: pp. 49-66
ISSN: 0080-4703
Collections: Royal Society Collection > Papers & Proceedings of the Royal Society of Tasmania
Additional Information:

Copyright Royal Society of Tasmania

Date Deposited: 22 May 2012 04:14
Last Modified: 18 Nov 2014 04:33
Item Statistics: View statistics for this item

Actions (login required)

Item Control Page Item Control Page