SoE 2003 > Biodiversity > 6.1 Terrestrial ecosystems

6.1 Terrestrial ecosystems

Reservation of terrestrial ecosystems for conservation has increased, with mechanisms to protect under-represented inland areas now the top priority

At January 2003, terrestrial protected areas in NSW covered approximately 5.8 million hectares or 7.3% of the State. This is an increase on the 6.6% reported in State of the Environment 2000. There are now extensive reserves across all the main ecosystem types on the ranges and the coast. The biggest gaps in the conservation system are in the central and western parts of the State.

NSW Indicators

Importance of the issue

The degradation and loss of terrestrial ecosystems are major threats to biodiversity. Healthy ecosystems contain a diverse set of organisms in soil, water and air, and an array of vegetation types that provide habitat for living creatures. Reducing and fragmenting the habitat available can lead to the extinction of species. Degradation affects the provision of critical ecosystem services, such as clean air and water, the recycling of nutrients, and the availability of resources such as food and fibre. Incremental changes to ecosystems may have long-term cumulative environmental impacts which severely degrade ecosystem health. The loss of ecosystems and their services is strongly linked with many other environmental problems, such as dryland salinity and land degradation, poor water quality and climate change. For more information on these, see Land 4.1, Land 4.2, Land 4.3, Water 5.3 and Atmosphere 3.2.

The extent of native vegetation cover is a surrogate indicator of the state of ecosystem diversity in NSW. The indicator does not reflect all ecosystem components, omitting, for example, fauna. However, ecosystem diversity is often correlated with the number, identity, condition and area of native vegetation types (Saunders et al. 1998).

Native forest and woodlands are estimated to have covered around 65% of NSW at the time the Europeans arrived in 1788. This compares with only 30% of the State now (Keith 2002).

Map 6.1 shows existing native vegetation across the State. Extensive clearing has occurred in the Central Division of NSW: the tablelands and the western slopes and plains that make up the wheat belt. Significant clearing has also occurred in the Eastern Division with its forestry, intensive agriculture and urban development (NLWRA 2001; NPWS in press). An average of 42% of native vegetation cover has been retained in the Central and Eastern divisions of the State, while in the Western Division approximately 97% of the native cover is still in place (NPWS in press).

Native vegetation is often heavily modified by, for example, grazing and changed fire regimes. The least disturbed ecosystems in NSW are in the eastern escarpment and on the less productive soils of the coast (Benson 1999). Much of the remaining native vegetation in inland NSW has been disturbed by intensive grazing of stock and feral animals (Pressey et al. 2000).

Localised clearing which fragments vegetation also has a significant impact on ecosystem condition. For example, the condition of the edge of remnants commonly suffers pest and weed invasion and changes to microclimates. These 'edge effects' can often extend hundreds of metres into a patch of vegetation, significantly reducing the total area in good condition in fragmented areas. Small patches and thin corridors of vegetation are also more vulnerable to the impacts of disease, fire, inappropriate clearing and other forces, and tend to be less genetically diverse.

This does not mean that isolated areas of native vegetation are of no value. Even areas that have been degraded may play a role in preserving biodiversity by providing, for example, corridors, refuges or stepping stones for the migration of flora and fauna.

Map 6.1: Existing native vegetation, 2002

Source: Keith 2002

Note: The data used to prepare this map only records losses in the extent of native vegetation cover through land clearing and does not indicate degradation or losses of vegetation or ecosystem diversity due to other processes, such as overgrazing and inappropriate fire regimes.

Response to the issue

The Government has responded to the decline in terrestrial ecosystems by:

• establishing international, national and state reserves and protected areas
• encouraging conservation on private land
• implementing legislative and planning controls on the clearing of native vegetation and protection of threatened species
• improving knowledge and collecting data on biodiversity and ecosystem condition.

The NSW Biodiversity Strategy sets policies aimed at conserving and improving terrestrial ecosystems (NPWS 1999a).

Terrestrial protected areas

The international Convention on Biological Diversity requires all member nations to develop a system of protected areas. Australia has responded by developing the National Strategy for the Conservation of Australia's Biological Diversity (DEST 1996), which calls for cooperation among local jurisdictions to establish a comprehensive, adequate and representative (known as 'CAR') system of protected areas. The CAR system is a major counter to declining biodiversity.

Nationally, the CAR reserve system aims to formally protect approximately 15% of the area of forested ecosystems that existed in 1788; 60% or more of the existing distributions of old-growth forest; and where practicable 90% or more of high-quality wilderness (AFFA 2002). State targets for all ecosystem types have yet to be set.

Map 6.2 shows the degree of protection of bioregions under the NSW reserve system. Four NSW bioregions achieve the CAR aim of 15% of the region formally protected.

Map 6.2: Reservation status of NSW native vegetation

Source: NPWS in press

Note: The bioregions are defined under the Interim Biogeographic Regionalisation of Australia (Environment Australia 2000).

Traditional conservation strategies have concentrated on protecting native biodiversity in formal reserves. However, the NSW Biodiversity Strategy recognises that effective and sustainable biodiversity management must encompass all tenures, including privately owned land (NPWS 1999a). Protected areas in NSW therefore include a number of different categories of land tenure.

At January 2003, terrestrial protected areas covered approximately 5.8 million hectares in NSW or about 7.3% of the State (NPWS in press). This has increased from the 6.6% reported in NSW State of the Environment 2000 (EPA 2000b). Table 6.1 provides details of the major changes in protected areas since the last report.

Table 6.1: Changes to NSW protected areas

Source: NPWS data, as at November 2002

Notes: ^(a) The majority of terrestrial protected areas in the formal reserve system of NSW are managed in the national parks estate under the National Parks and Wildlife Act 1974.
^(b) Terrestrial areas protected in accordance with Australia's international obligations. While not necessarily part of the formal reserve system, the Environment Protection and Biodiversity Conservation Act 1999 obliges the Commonwealth and the States to protect these areas. In NSW most were part of the national parks estate prior to the enactment of this statute.

State forests estates, Commonwealth national parks and agreements on private land also provide protected areas. There are approximately 2.7 million hectares of state forest contributing to biodiversity protection in NSW, including 615,024 hectares of formal and informal reserves. Almost half of this reserve area is in north-eastern NSW, dedicated as a Special Management Zone.

Conservation on private land

Encouraging conservation on private land is an integral part of the NSW Biodiversity Strategy. There are a number of different types of agreements used for this purpose.

Voluntary Conservation Agreements (VCAs) are joint agreements between landowners and the NSW Minister for the Environment which provide permanent protection for areas of high conservation value on private property. These agreements are established under the National Parks and Wildlife Act 1974 and registered on the land title, which legally binds current and future owners of the property. At December 2002, there were 123 VCAs in NSW covering about 9240 hectares. The lands covered by VCAs typically have at least one of the following features: habitat for species listed as nationally endangered or as threatened in NSW; declared wilderness; high quality remnant vegetation; or sites of Aboriginal significance.

Wildlife Refuges are voluntary agreements between landholders and the National Parks and Wildlife Service that protect the native plants and animals on a property. Agreements can be entered into for the purpose of conserving, preserving, propagating and studying native plants and animals; conserving and studying natural environments; or creating simulated natural environments. At December 2002, there were 586 Wildlife Refuges in NSW with an area greater than 1.6 million hectares.

The Nature Conservation Trust of NSW also encourages landholders to enter into cooperative agreements for the management and protection of land in private ownership. The Trust was established in 2001 and focuses on sites that are significant for the conservation of natural heritage. Another Trust function is to purchase private land, establish conservation controls on the land title, and sell the land back to private ownership. To achieve this, a revolving fund has been established with initial funding of $2 million from NSW and the Commonwealth.

At the national level, the National Reserve System Program provides opportunities for the joint acquisition of land for long-term protection, either in a state's reserve system or by conservation covenants. Incorporated non-profit community groups can participate, although most of the activity under this program involves state governments.

Legislative and planning controls

Controls on clearing native vegetation help prevent the loss and degradation of terrestrial ecosystems. The Native Vegetation Conservation Act 1997 is a key response to terrestrial ecosystem decline in NSW (see Biodiversity 6.2). The Threatened Species Conservation Act 1995 is the main legislative tool for the protection of all threatened plant and animal species in NSW (see Biodiversity 6.3).

Planning instruments which are used to protect native vegetation and ecosystems include the Environmental Planning and Assessment Act 1979 and a number of State environmental planning policies (SEPPs) which conserve selected ecosystem types or specific categories of native vegetation in NSW: SEPP 14 – Coastal Wetlands, SEPP 19 – Bushland in Urban Areas, SEPP 26 – Littoral Rainforests, SEPP 44 – Protection of Koala Habitat and SEPP 71 – Coastal Protection.

Local government has a direct role in conserving biodiversity in NSW through its traditional involvement in planning and development and increasingly through its roles in environmental management. Many councils and shires are at the forefront of work to preserve or restore local conservation values, in partnership with community groups.

Priority areas for enhancing terrestrial ecosystems

Assessments under the NSW Biodiversity Strategy identify areas and features of high biodiversity significance and advise on appropriate conservation measures. These assessments are the first step in providing information to plan the management of natural resources. They will be used, for example, to expand the CAR reserve system and support the Regional Vegetation Management Planning process (see Biodiversity 6.2).

The State Conservation Monitoring Project, funded as part of the implementation of the NSW Biodiversity Strategy, is refining conservation priorities at the ecosystem scale. Statewide conservation priorities are being established with reference to existing reserves and past clearing patterns, coupled with predicted future threats, such as salinity and clearing (NPWS in press).

Private land which is added to the reserve system comes from several sources: existing Crown or leasehold land or purchased by the Government. The factors determining whether an area is added to the reserve system include its suitability, availability, current threats and the resources available. Ecosystems that are a high priority for protection are often so fragmented that extensive reservation may not be considered appropriate or achievable.

Improving knowledge

Efforts are under way to address the lack of data on ecosystem condition through a number of programs including:

• research to assess vegetation extent and condition within particular bioregions as part of the NSW Biodiversity Strategy
• high-definition floristic mapping of native vegetation through the Native Vegetation Mapping Program
• work to classify and assess the status of the State's vegetation by the Royal Botanic Gardens and Domain Trust.

Effectiveness of responses

Ecosystem types which are priorities for conservation in the Eastern Division have generally been protected. Some individual ecosystems may still be under-represented, however, as most protected areas tend to be located on elevated rugged land, areas with poor soils or land with low potential (Benson 1999; Pressey et al. 2000). Across all divisions, most of the under-represented ecological communities are on privately owned or leasehold land (Pressey et al. 2000).

Although the protected area system in NSW is extensive and has been significantly increased recently, it does not yet fully meet the comprehensive, adequate and representative objective. Reservation is better in the east of the State than in the west at all scales. For example, in the bioregions of the Eastern and Central divisions, 9.5% of native vegetation is in reserves compared with 3% in the Western Division (Pressey et al. 2000).

Future directions

Government needs to continue to add to the terrestrial protected area system in priority areas. The challenges are currently in the State's Western and Central divisions. With losses of up to 100% in some vegetation communities (Pressey et al. 2000), achieving a true CAR protected area system in NSW will not be possible without extensive reconstruction of habitats.

Government and landholders should work in partnership to continue to develop better models and levels of expertise for conservation on private land. Practices on private lands need to protect or restore ecosystems and minimise or reverse habitat fragmentation, while at the same time providing landholders with appropriate levels of incentive and investment security.

Efforts to improve information on the condition of ecosystems should continue.

Linked issues

2.1 Population and settlement patterns

4.1 Land-use changes

4.2 Soil erosion

4.3 Induced soil salinity

5.1 Freshwater riverine ecosystem health

6.2 Native vegetation clearing

6.3 Terrestrial species diversity

6.6 Aquatic ecosystems