Jim Jim Creek bordered by tropical forest in Kakadu National Park, Northern Territory.
Biological diversity, also known as biodiversity, is the full range of plants, animals and microorganisms occurring in a given area, along with the genes they contain and the ecosystems they form. Conservation of biological diversity is a key part of sustainable forest management, and its goal is the continued existence of ecosystems, species and the genetic variability within these species.
Biological diversity is usually considered at three levels: ecosystem diversity, species diversity and genetic diversity. The nine indicators in this criterion are divided into three subcriteria that match these levels.
Understanding the extent, geographic distribution, major forest types and growth stages of Australia's forests underpins the effective management of forest ecosystems, through the development of appropriate legislation and policies, monitoring of forest condition, and assessment of forest management outcomes.
The category 'Native forests' is the major category of forests; it is divided into closed, open and woodland forests according to canopy cover (decreasing from closed to open to woodland forests). Eight broad national native forest types have been defined, with the 'Eucalypt forest' type subdivided by height and growth form. 'Industrial plantations' form a second forest category, being commercial plantations grown for wood production. A small third category, 'Other forest', contains a range of small-scale planted forests, including those in agroforestry and farm forestry systems, sandalwood plantations and environmental plantings.13
Across these categories, forests are allocated to six tenures: leasehold forest, multiple-use public forest, nature conservation reserve, private land, other Crown land, and unresolved tenure.
Area statistics are required for the interpretation of many of the indicators used in SOFR 2013, and Indicator 1.1a ('Area of forest by forest type and tenure') is therefore a keystone indicator in the SOFR series. Area information is used to understand whether forest ecosystems and their embedded diversity are being maintained. The reported area of Australia's forest has changed over time as methodologies for forest assessment have improved. SOFR 2013 is the first national report to use a 'Multiple Lines of Evidence' approach to determining Australia's forest area, combining data from states and territories with a range of remotely sensed forest cover data to map forest communities at a finer scale and with increased accuracy.
Indicators for this subcriterion provide data on Australia's forest area by type, growth stage and tenure, and report on the forest area in reserves of various types or which are protected through other arrangements such as covenants. Different land ownership and management structures can affect forest ecosystems in different ways, and data on land tenure can therefore provide information on the extent of protection, clearing, fragmentation or other alteration. Fragmentation of native forest is also monitored as a measure of the effects of various kinds of natural disturbance and human-caused disturbance on forest ecosystems.
Australia is estimated to be home to some 566 thousand species, of which over 147 thousand species have been described. Of the described species, about 92% of the plants, 87% of the mammals and 45% of the birds are endemic—that is, found only in Australia. An important measure of species diversity is the number of forest-dwelling species, which are species that may use forest habitat for all or part of their lifecycles. Another important measure is the number of forest-dependent species, which are those species that require a forest habitat to complete all or part of their lifecycles; these are a subset of the total number of forest-dwelling species.
Knowledge of the plant, animal and other species present in a forest is a pre-condition for the effective management of that forest. Information on whether populations of species are increasing or decreasing can indicate the extent and condition of forest habitat and changes in habitat, and is needed to support conservation strategies. For forest covered by Regional Forest Agreements, state governments have developed a set of criteria that include broad benchmarks for the in-situ conservation of forest biodiversity.
A number of forest-dwelling and forest-dependent species and forest ecosystems are listed as threatened on lists compiled nationally and by states and territories. Knowledge of the threats and threatening processes faced by listed species and ecosystems assists in their protection.
Conservation of forest genetic resources is linked both to the conservation of forest biodiversity and to the availability of forest species for commercial or environmental use. Indicators in this subcriterion examine the risk of loss of genetic diversity in forest plants and animals, and the conservation measures in place to minimise that risk. The indicators also provide an inventory of tree breeding and improvement programs that act as repositories of native forest genetic resources, and that contribute to knowledge about the conservation of the genetic diversity of Australia's native forest and plantation tree species. Australia's forest genetic resources are generally highly accessible, and a very large amount of genetic material, mainly seed, has been made available throughout Australia and globally.
Native forest species and communities in Australia are conserved in protected areas such as nature conservation reserves and national parks. In addition to genetic resource conservation through forest reservation, conservation plantings and seed orchards (stands specifically planted and managed for seed production) have been established for a number of threatened species.
Australia's forest genetic resources also play an important role in maintaining and improving the productivity of commercial plantations grown for wood production. This can occur, for example, through selection of trees that have high growth rates and superior wood quality, that are better adapted to changing climatic conditions, such as lower rainfall or higher temperatures, or that are resistant or tolerant to pests and diseases. The genetic base of Australian native forest trees employed in commercial plantations has also been brought into seed collections, seed orchards, and improvement and breeding programs.