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M.J . Brown and J . Read
The coniferous dominants-Athrotaxis, Lagarostrobos, and Phyllocladus-each exhibit continuous regeneration when they occur in implicate
forests or open situations in montane forests where there is no competition
from grasses or from grazing (Cullen, 1987; Read & Hill, 1988; Gibson &
Brown, 1991; Barker, 1992). In mature, closed forests these species have
unimodal or multimodal distributions (e .g., Ogden, 1978; Kirkpatrick &
Harwood, 1980), suggestive of initial establishment and extended recruitment after catastrophic disturbance such as landslides (Cullen, 1991),
floods (Gibson & Brown, 1991), or wildfire (Gibson, 1988; Read & Hill ,
1988). Forests containing mixtures of these species are not necessarily
self-replacing. However, canopy composition may remain constant over
long periods of time in these forests because of the long life-spans of the
trees (several hundred to over 1000 years).
Conservation and Management
In common with much of the world's remaining natural vegetation, there
is decreasing opportunity for management of rainforest by benign neglect,
even within stringently policed protected areas. For example, rainforest is
very vulnerable to damage on a broad scale by wildfire and to fragmentation by such infrastructure developments as roads and power lines . The
human pressures both within and outside reserves are such that active
monitoring and management of the remaining rainforest are needed to
ensure its perpetuity. Much of the Tasmanian rainforest and wet eucalypt
forest is old-growth i.e., the forests are ecologically mature and essentially
unmodified by humans (RAC, 1991). As well as their value for the maintenance of biodiversity and ecosystem processes, they contain valuable
timbers and other economic resources. Management of the forests for
their conservation therefore needs to address both sets of values.
Clearing
It is thought that about 15% of the rainforest (Hickey, 1990) and 35% of
the wet eucalypt forests (Wells, 1989) have been lost to farming or other
use. About two thirds of the blackwood swamp forests of northwestern
Tasmania have been cleared for agriculture. About 13,000 ha of this
marginal rainforest type remains and is managed primarily for the blackwood (Acacia melanoxylon) production. A conservation evaluation of
these forests has been completed (Pannell, 1992). Small amounts of
rainforest on public lands have been clear felled and burned for sowing to
eucalypt forest, and some areas of logged mixed forest and damaged
rainforest on basalt soils have been converted to eucalypt on industrial
private lands. Only about 4% of the rainforest and mixed forest is privately owned, so that management responsibility and conservation needs
can largely be addressed on public land tenures.
While most of the remaining old growth forests are in relatively pristine
M.J . Brown and J . Read
The coniferous dominants-Athrotaxis, Lagarostrobos, and Phyllocladus-each exhibit continuous regeneration when they occur in implicate
forests or open situations in montane forests where there is no competition
from grasses or from grazing (Cullen, 1987; Read & Hill, 1988; Gibson &
Brown, 1991; Barker, 1992). In mature, closed forests these species have
unimodal or multimodal distributions (e .g., Ogden, 1978; Kirkpatrick &
Harwood, 1980), suggestive of initial establishment and extended recruitment after catastrophic disturbance such as landslides (Cullen, 1991),
floods (Gibson & Brown, 1991), or wildfire (Gibson, 1988; Read & Hill ,
1988). Forests containing mixtures of these species are not necessarily
self-replacing. However, canopy composition may remain constant over
long periods of time in these forests because of the long life-spans of the
trees (several hundred to over 1000 years).
Conservation and Management
In common with much of the world's remaining natural vegetation, there
is decreasing opportunity for management of rainforest by benign neglect,
even within stringently policed protected areas. For example, rainforest is
very vulnerable to damage on a broad scale by wildfire and to fragmentation by such infrastructure developments as roads and power lines . The
human pressures both within and outside reserves are such that active
monitoring and management of the remaining rainforest are needed to
ensure its perpetuity. Much of the Tasmanian rainforest and wet eucalypt
forest is old-growth i.e., the forests are ecologically mature and essentially
unmodified by humans (RAC, 1991). As well as their value for the maintenance of biodiversity and ecosystem processes, they contain valuable
timbers and other economic resources. Management of the forests for
their conservation therefore needs to address both sets of values.
Clearing
It is thought that about 15% of the rainforest (Hickey, 1990) and 35% of
the wet eucalypt forests (Wells, 1989) have been lost to farming or other
use. About two thirds of the blackwood swamp forests of northwestern
Tasmania have been cleared for agriculture. About 13,000 ha of this
marginal rainforest type remains and is managed primarily for the blackwood (Acacia melanoxylon) production. A conservation evaluation of
these forests has been completed (Pannell, 1992). Small amounts of
rainforest on public lands have been clear felled and burned for sowing to
eucalypt forest, and some areas of logged mixed forest and damaged
rainforest on basalt soils have been converted to eucalypt on industrial
private lands. Only about 4% of the rainforest and mixed forest is privately owned, so that management responsibility and conservation needs
can largely be addressed on public land tenures.
While most of the remaining old growth forests are in relatively pristine