Open Access Repository

Vegetation and fuel dynamics following clearfelling of dry Eucalypt forests on Dolerite in Southeastern Tasmania with special reference to the use of fire in forest regeneration

Downloads

Downloads per month over past year

Dickinson, KJM (1985) Vegetation and fuel dynamics following clearfelling of dry Eucalypt forests on Dolerite in Southeastern Tasmania with special reference to the use of fire in forest regeneration. PhD thesis, University of Tasmania.

[img]
Preview
PDF (Front matter)
front-Dickinson...pdf | Download (1MB)
Available under University of Tasmania Standard License.

[img]
Preview
PDF (Whole thesis)
whole-Dickinson...pdf | Download (60MB)
Available under University of Tasmania Standard License.

Abstract

In order to supply eucalypt pulpwood to an expanding woodchip
industry the silvicultural management practice of clearfelling followed
by slash-burning was adopted in the dry eucalypt forests on dolerite in
southeastern Tasmania.
To provide data on the vegetation and fuel dynamics following dry
forest utilisation, a study area with comparable sites that were (a)
unlogged, (b) clearfelled, (c) clearfelled and slash-burned, was
monitored over a 24 month period. Detailed records were made of plant
species composition and cover on floristically similar permanent plots
on each of these sites. Fuel levels, fuel structure and fuel composition
were measured at the study area, and at other East Coast sites of
varying ages since slash-burning. A monthly bird census was conducted in
the main experimental area to establish the inter-relationships of the
avifauna with particular plant species and habitats.
Following clearfelling there was found to be marked variation in
the growth response of plant species, due to environmental situation,
degree of disturbance, and intensity of slash-burn. Moreover, the effect
of these factors on individual species was greatly influenced by
selective grazing and browsing, predominantly by native fauna. The
combination of burning and predation tended to favour unpalatable
species which recovered rapidly by vegetative means.
The succession of plant species following fire in dry forest
communities most closely approximated the initial floristic composition
model. Most of the plant species recovered rapidly with a progressive
increase in species richness for at least two years after disturbance.
Slash-burning was found to reduce the levels of fine fuel (2.0cm
in diameter or thickness) left as a result of clearfelling, but the
practice was ineffective in reducing the volume of coarse fuel (2.0cm
in diameter or thickness). However, over time, this relative reduction of fine fuel was only persistent in the compacted ground fuel layer, as
the regenerating stand rapidly recovered the above-ground, vertical fine
fuel structure.
Experiments were conducted on various dry forest and wet forest
plant species and fuel components, in order to establish their energy
content and relative flammability. It was found that eucalypt dry forest
species and fuel components had the highest energy content and the
greatest tendency to propagate fire, whereas species from wet forest and
Casuarina dry forest communities propagated fire less readily. Species
from dry habitats had, in general, low ash contents, high energy levels,
high volatile oil contents and low moisture contents. Wet habitat
species had high percentages of moisture and ash. As a result, general
support could be given to the hypothesis that natural selection has
favoured flammable characteristics in fire-dependent plant communities.
The gains from the retention of natural eucalypt regeneration after
clearfelling (i.e. forest management in the absence of hot, slash-burns)
may generally offset the short-term advantage of reduced fire hazard
which results from slash-burning.

Item Type: Thesis (PhD)
Additional Information:

The University is continuing to endeavour to trace the copyright owner(s) and in the meantime this item has been reproduced here in good faith. We would be pleased to hear from the copyright owner(s) - Copyright the Author

Date Deposited: 12 Feb 2013 03:34
Last Modified: 15 Sep 2017 01:06
Item Statistics: View statistics for this item

Actions (login required)

Item Control Page Item Control Page
TOP