Biological diversity is usually considered at three levels:
‘Genetic diversity’ refers to the variety of genetic information contained in all individual plants, animals and micro-organisms. It occurs within and between populations of species as well as between species.
‘Species diversity’ refers to the variety of living species.
‘Ecosystem diversity’ refers to the variety of habitats, biotic communities and ecological processes, as well as the diversity present between and within ecosystems..
1.2.1 Genetic diversity
Empirical data on genetic variation within and between species is sparse and generally restricted to a small number of species, primarily vertebrates and vascular plants. The time and cost of analyses to incorporate a full consideration of genetic variation is beyond the scope of the CRA process.
The national criteria state that “The reserve system should seek to maximise the area of high quality habitat for all known elements of biodiversity “(criterion 5). The agreed approach to address the genetic component of this diversity in the assessment has been to analyse the spatial and environmental spread in the representation of vegetation classes and species populations within the Region. Threatened species or groups of species that require targeted assessments to ensure their survival in situ will have a particular dependence on the maintenance of genetic variation.
As knowledge of intra-specific variation and techniques for assessing it improve, it will be necessary to review the strategies for ensuring preservation of genetic variation.
1.2.2 Species diversity
Under the National Forest Policy Statement (Commonwealth of Australia 1992a), Australian governments agreed to manage for the conservation of all species of Australia's indigenous forest fauna and flora throughout those species' ranges and to maintain the native forest cover where a reduction in this cover would compromise regional conservation objectives, consistent with ecologically sustainable management. The national forest reserve criteria, jointly agreed by the Commonwealth and the States, identify objectives in relation to species conservation (see Box 1 above, point 5).
In particular, assessment of species-level biodiversity in Central Highlands forests for the CRA required a review of the conservation status of threatened taxa, their susceptibility to extinction and an evaluation of the effects of disturbance on each of these taxa. Existing or proposed management actions are also addressed.
1.2.3 Ecosystem diversity
Ecosystem diversity encompasses the broad differences between and within ecosystem types in relation to the diversity of habitats and ecological processes. It is more difficult to define than species or genetic diversity because the 'boundaries' of communities (associations of species) and ecosystems are often indistinct. The ecosystem concept is dynamic and thus variable, and it can also be applied at different scales.
Forest ecosystems are defined in the nationally agreed criteria for a CAR reserve system for forests and in Victoria it has been agreed that Ecological Vegetation Classes (EVCs) are equivalent to forest ecosystems for the purposes of the CRA assessments. This assumes a correlation between the occurrence of entities defined by certain structural, floristic and environmental features and the occurrence of particular suites of fauna.
1.3 Conservation of biodiversity
1.3.1 National and State obligations and actions
The Commonwealth and Victorian governments have a number of legislative and international responsibilities in connection with the conservation of biodiversity. Of particular relevance are the Convention on Biological Diversity, the Commonwealth Endangered Species Protection Act 1992 and Victorian Flora and Fauna Guarantee Act 1988.
The Convention on Biological Diversity
Conservation of biodiversity is a foundation of ecologically sustainable development and one of the three principal objectives of the National Strategy for Ecologically Sustainable Development (Commonwealth of Australia 1992b).
The Convention on Biological Diversity, ratified by Australia on 18 June 1993, deals at a global level with the full range of the conservation of biological diversity, its sustainable use, and the fair and equitable sharing of the benefits arising from this use. The National Strategy for the Conservation of Australia’s Biological Diversity, signed by the Commonwealth and all State and Territory governments, provides the framework for giving effect to Australia’s international obligations (Commonwealth of Australia 1996). Under the Strategy, governments in Australia have undertaken to identify the terrestrial, marine and other aquatic components of biodiversity that are important for biodiversity conservation and ecologically sustainable use.
Under the Endangered Species Protection Act 1992, the Commonwealth is responsible for identifying endangered species and their habitats for the purpose of analysis of threats and potential for recovery and for developing measures to ensure their future viability.
The primary purpose of the Act is to promote the recovery of species and ecological communities that are endangered or vulnerable and to prevent other species and communities from becoming endangered or vulnerable. The Act aims to reduce conflict in land management, to provide for public involvement and better understanding, and to encourage cooperative management for the conservation of endangered species and communities.
Provision is made under the Act for a scientifically based listing process that identifies nationally endangered and vulnerable species, endangered ecological communities and key threatening processes of national importance. Those species, communities and threatening processes are listed in Schedules to the Act.
The Act promotes the use of ‘Recovery Plans’, to help in the recovery of endangered species and ecological communities, and ‘threat-abatement plans’, for reducing the impact of threatening processes.
Victorian Flora and Fauna Guarantee Act 1988
The Flora and Fauna Guarantee Act 1988 provides a framework for the legal protection of Victoria's flora and flora, and for a major program of State Government and community action. The aim is to ensure that Victoria's native flora and fauna survive, flourish and retain their potential for evolutionary development.
The Act provides for native species or biological communities, which have been identified as being threatened, to be listed in one of its schedules.
It also allows for the listing of threatening processes which may affect the long term survival and evolutionary development of flora and fauna.
When a listing occurs, an action statement must be prepared as soon as possible detailing what measures are needed for the management of the listed species, biological community or potentially threatening process. Action Statements take into account social and economic considerations.
Interim Conservation Orders (ICOs) can also be made in cases where the threat to the critical habitat of a listed species or biological community is considered so urgent that immediate action is required.
Victorian National Parks Act 1975
The National Parks Act 1975 provides for the establishment, protection, management and use of National, State, and Wilderness Parks, as well as other parks and reserves. Under the Act, the Director is required to ensure that each National, State and Wilderness Park is controlled and managed in a manner that will preserve and protect the natural condition of the park and its indigenous flora and fauna. The Act requires a management plan to be prepared for each park.
Other relevant legislation includes the Crown Land (Reserves) Act 1978, the Forests Act 1958 and the Heritage Rivers Act 1992. A list and description of key Commonwealth and State legislation relating to RFAs in Victoria is provided in Appendix 1 of the Central Highlands CRA Summary Report and in the statewide assessment of Ecologically Sustainable Forest Management.