Since European settlement and the onset of river regulation,
the environmental characteristics of the Murray-Darling basin
have been dramatically changed from the natural flow
regimes.
Because of impoundments, non seasonal releases of
water, the reduction of small and medium sized freshes and other
changes to the natural water regime; many wetlands along
the Murray-Darling River systems are degraded.
The natural environmental cycle of many of these wetlands has in many cases
being irretrievably changed, with many wetlands kept artificially
inundated or artificially dry.
There are major environmental, and also economic benefits to
restoring these floodplain wetlands to a more natural cycle of
wetting and drying. Environmentally, the wetlands are beneficial
to the ecosystem in many ways, as pools of biodiversity (always
significant around ecotones), nursery areas for native fish and
crustaceans, nutrient sources for the rivers, and natural flood
buffers.
Economically, the wetlands are also beneficial; they can
provide extra storage for water, can be sustainably cropped when
dry, can be sustainably grazed by livestock and can help to
increase stocks of native fish species.
They provide valuable
recreational areas for bushwalking, picnicking, birdwatching and
other eco-tourism type activities. Wetlands are important areas
of cultural significance; they are often sites of Aboriginal
habitation, often for thousands of years.
They are also important
pyschologically, whether for Indigenous spiritual reasons, or for
a wildnerness experience where people can commune with nature and
rediscover their inner peace.
It is vitally important that a river catchment is considered
in an holistic manner, from its source to the sea. Every change
that is made to the river system may have benefits or
repercussions further downstream, and these must be taken into
account when planning anything, from a single rehabilitation
project to a new irrigation development. The interlinked
complexity of natural ecosystems is only just being explored; and
unfortunately, many changes humans have made to these
environments now and in the past, are only just becoming
apparent. Very often, what we have done is either irreversible or
will take many decades to rectify; and unfortunately, often the
only thing we can do is to address the problems and not the
causes. The wetlands and the entire floodplain, are integral
components of the river system and must be looked at
holistically. It is vitally necessary to provide environmental
flows to the entire river floodplain, including its estuarine
mouth, and to see the system as the whole that it is, and not to
let petty parochial interests prevent this goal.
