Sunday, August 30, 2009

Karst wetland management practices

the effects of these activities are mostly irreversible
and as such are regulated in Queensland through the
Integrated Planning Act 1997 and/or the Environmental
Protection Act 1994. any new or modified
development may require appropriate development
approval under this legislation and must comply with
any conditions applied to this approval.
some karst wetlands are now protected under the
Queensland Nature Conservation Act 1992 through
the declaration of protected areas such as national
parks. some are also protected through other national
legislation as outlined in the national conservation
status section.
Land and water use
Land and water use that changes water flow and the
processes feeding karst wetlands can also cause direct
or indirect impacts on the wetland. Changes or
reductions in water flows through water extraction,
damming or diversions can reduce water tables or
water input balances which can result in structural
failures in karst wetland caves and other underground
voids that contain wetlands and impact on the
delicate ecological balance on which wildlife depend.
stygobites are particularly fragile to these changes.
the removal of water-filtering vegetation or changes to
soil cover can cause siltation of watercourses and
ultimately karst wetlands, where they are directly fed
from external streams, smothering small wildlife.
any extractive industry within a karst wetland
catchment, be it geological, biological or chemical
can change balances in karst systems resulting in
effects on geological and ecological processes and
ultimately the wildlife that live there.
since catchments for karst wetlands may extend
beyond the karst system, land managers should seek
advice before installing structures that may alter the
hydrology of karst wetlands. Further information
about current legislative requirements regarding
construction of dams, bores, bund walls, drains and
other structures is available from the Queensland
department of natural and Resources and Mines
(nR&M) website (
Land use activities within karst wetland catchments
should aim to maintain a constant and adequate level
of natural vegetation and ground cover. activities
should be conducted in a manner that prevents or
minimises soil disturbance, erosion and water
quantity and quality changes. activities should
comply with appropriate legislation, industry codes
of practice and guidelines.
Managing karst wetlands
the geological, chemical and hydrological systems
that build and maintain karst wetlands are inherently
governed by the relationships between water, land,
vegetation and soil. any change in the input of one
or more of these aspects can pose serious threats
to the integrity of both karst systems and their
associated wetlands.
Runoff from non-karst areas can contribute to
subterranean wetlands. this means that threats can
be both direct and indirect. Management of karst
wetlands must take account of direct threats on karsts
such as mining and indirect threats such as pollution.
these may be difficult to quantify.
Consequently, development proposals and planning
should consider the breadth of the karst wetland’s
catchment (including that beyond the limestone
outcrop) and apply appropriate environmental
monitoring and management measures. activities
within the catchment of a karst wetland should
comply with appropriate legislation and conditions
and follow best practice management regulations,
codes of practice and guidelines.
to protect karst wetlands there needs to be an
understanding of where they occur and how they
might be impacted upon. this can only be resolved by
systematic surveys and mapping the extent of the karst
wetlands, catchment boundaries and their
hydrological interactions.
UNDErsTANDiNG and recognising the
extent of karst wetlands, their catchments
and hydrological interactions through
systematic surveys and mapping, together
with appropriate planning and management,
are the keys to protecting karst wetlands.
Mining and quarrying
some of Queensland’s karst landscapes have been
subject to mining and quarrying for a variety of
products. Mining and quarrying can directly destroy
species and their habitat. these activities can cause
direct destruction to a karst wetland but may also
cause indirect threats to the system through pollution,
changing the biological and chemical balance and
altering karst wetland characteristics such as water
flows. Mining and quarrying can also have impacts on
the visual amenity of a site and the value of the site
for other uses such as recreation and water use.

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