Freshwater ecosystems


Ecosystem reserves: definition and management



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3.6 Ecosystem reserves: definition and management


All States have established wetland inventories; however these inventories all remain unfinished or lack comprehensive coverage. It is a matter of great concern that States do not have comprehensive inventories of freshwater ecosystems, including both lotic and lentic (“still” and “flowing”) freshwater environments.

No biodiversity program can hope to be effective until consolidated overview data is available on ecosystem type, size, tenure, condition and value.

In her LWRRDC paper on river values, Helen Dunn recommended (Dunn 2000:63) that:



A national system of river reserves should be a core strategy for protection:

A national system of river reserves should be established in line with the reserve systems for other habitats. Such a system needs to be developed at a national level in order to ensure that the full range of river types is protected. Some rivers included in such a representative reserve system will of necessity not be in fully natural condition. Nevertheless they will contribute to a reference suite of river or river sections. Development of an appropriate bioregional framework or river classification scheme to underpin a reserve system is a priority.

Assessments for river classification, as well as management and rehabilitation principles, stress the importance of baseline geomorphic characterisation of rivers. Geomorphic studies provide a base for an assessment of freshwater conservation values from a biophysical perspective48. Such studies can be followed by prioritisation of river management and rehabilitation works, looking at recovery potential both from geomorphological and biological points of view.

For freshwater systems, It appears important to initially apply a “geomorphic template” as the basis of:



  • ecosystem characterisation,

  • assessment of conservation value, and

  • the development of management priorities.

Reserves along rivers need to be assessed and managed for their representative (or special) geomorphological and ecological values, while some sites can be used as geomorphological benchmark sites which may be used to guide future rehabilitation works and management programs.

Assessment and classification methods are listed below in Appendix 1.

The issue of how the catchment of a reserve might be protected provides an obvious complication with regard to freshwater reserves that does not generally apply to terrestrial or marine reserves49. The use of land and water upstream of the reserve will affect the viability of the reserve itself. The existence of downstream dams and weirs will inhibit or prevent fish passage.


This aspect means that creation and management of the reserve must bear catchment issues in mind – and in some cases, seek to influence activities within the catchment in order to protect values of the reserve. This complication is just that: a complication. It does not imply that the concept of a representative freshwater reserve is somehow different in principle to a terrestrial or a marine reserve. The essence of all reserves is that boundaries can be drawn, and management plans and programs prepared, to effectively protect the target ecosystem.

4. Cumulative impacts and the need for strategic planning.


Chapter updated 20 September 2002.

4.1 Cumulative effects: overview


Managing cumulative effects is one of the most important and intractable problems facing the water resource industry today. All Australian States have put in place statutory impact assessment procedures for assessing the likely effects of large (‘State significance’) development proposals . All States also have strategic landuse planning procedures specifically designed to control the cumulative effects of small developments, such as housing. The cumulative effects of fishing effort on fisheries resources are also specifically recognised and controlled by all State governments.
However, water developments generally ‘slip through’ such procedures, and their cumulative effects are poorly controlled in all States. Although most developments affecting water resources take place through small and medium sized projects (farm dams, levee banks, weirs etc.) the need to manage the cumulative effects of these projects is generally not specifically recognised in State water resource legislation. Moreover, in those States which have developed statutory catchment planning frameworks, these frameworks have not implemented effective mechanisms for managing cumulative effects, even though these effects are seriously degrading the catchment resource. This paper argues that, as a matter of urgency, cumulative effects within the water resource industry must be taken much more seriously, and that controls must have four critical elements:

  • the need to establish strategic development caps on a catchment basis must be formally recognised in water resource legislation, and appropriate procedures must be established to set and implement the caps;

  • caps must be comprehensive, covering: water extraction from both surface and groundwaters; the construction of farm dams (number and volume), agricultural drains, impediments to fish passage, and levee banks; the development of irrigated pasture; the clearance of deep-rooted vegetation, and activities (eg: stock access) capable of degrading riparian vegetation.

  • the caps on development must be set well ahead of the point where the catchment enters a stressed or crisis situation; and

  • the caps must be set in a precautionary way.

4.2 Cumulative effects: background


The importance of managing the cumulative effects of incremental development has been seriously underestimated, and all Australian States have failed to take effective action in this regard.
Strategic planning frameworks specifically designed to manage the cumulative impacts of incremental development are an accepted feature of both local government land use planning in Australia, and the management of fisheries by State government agencies. While it is possible to argue that these frameworks have been less effective than might have been expected, they are nevertheless in place, and they do explicitly recognise the need to manage cumulative effects, and the difficulty involved in managing these effects. An important feature of the management of freshwater resources in all Australian States is that such frameworks have either not been put in place, or have not been effectively implemented.

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