NAFI |Facts & Figures

Australia's National Association of Forrest Industries

Forestry Facts: An Overview

Statistics

Old Growth Forests

Biodiversity

Bushfires

Australia's changing forests

Native forests

Forests and the Economy

Eucalypt (Hardwood) Plantations

Pine (Softwood) Plantations

Multiple use forests

Woodchips

Pulp and Paper

Regrowth forests

The World's Rainforests

The Greenhouse Effect

Glossary of Terms

Timber construction in bushfire areas

Biodiversity

The terms biodiversity and biological diversity are used synonymously. Biological diversity encompasses the variety of life on earth and is generally considered at three levels:

genetic diversity - the total range of genetic information contained in the genes of all living things.

species diversity - the variety of species of organisms on earth; and

ecosystem diversity - the variety of habitats, biotic communities, and ecological processes and biosphere.

The conservation of the variety of life on earth and the maintenance of ecological systems and processes are attracting increasing attention and debate as human population expands and consumption of resources increases.

Plants and microorganisms synthesise carbohydrates and similar compounds from carbon dioxide and water; some also capture atmospheric nitrogen, providing the basic building clocks for protein synthesis. Other organisms, which depend on these basic energy sources, participate in food chains that recycle the fixed carbon and other nutrients taken up by plants.

The complex relationships between the broad spectrum of plants and animals regulate the composition of the atmosphere, have an important influence on the properties of water in the biosphere and are fundamental to the survival of humanity. The relationships are dynamic in time and space. There is evidence of evolutionary changes over long periods of time and of resilience to short term disturbance. In fact natural disturbance by fire or other agencies may be the dominant force in determining the evolution and development of the world's biodiversity.

Economic growth and development obviously involve changes, and every ecosystem cannot be preserved intact.

While there is broad agreement about the need to conserve biological diversity there is debate about how it can be achieved given the needs and aspirations of society.

Australia's biodiversity
The biological diversity of Australia is special. Australia's flora and fauna are distinctive, reflecting the country's long isolation from other parts of the world and their continuing evolution. While some of the biota of earlier environments have persisted due to the stability of the continent there has been extensive adaptation to increasing aridity, low soil fertility and frequent burning.

European settlement of Australia resulted in a number of changes that have had a substantial impact on both the landscape and biodiversity.

These include:

the rapid cessation of regular burning by Aborigines;

the keeping of large numbers of hard hoofed domestic animals such as sheep, horses and cattle;

the deliberate and accidental introduction of new plants, many of which have become serious pests;

the spread of feral animals-for example, foxes, carp, pigs and cats which either prey on or compete with native species;

the clearing of land for agricultural and urban development;

the establishment of orchards and plantations; and

the regulation of the flows of rivers and the establishment of water storages and irrigation systems.

These changes together with rapid population and economic growth over the past fifty years have not only significantly affected Australia's biodiversity but also generated the wealth required to address some of the more pressing issues relating to its conservation.

To date, much of the focus in conserving Australia's biodiversity has been on developing extensive systems of reserves that exclude commercial activities such as mining, forestry, grazing and apiculture and on the special needs of a limited number of species such as the koala which is not endangered. Insufficient attention has been given to linking the conservation of biodiversity with sustainable development. Unless this link is more strongly developed Australia's financial capacity to protect biodiversity will be constrained.

Forests and biodiversity

At the time of European settlement it was estimated that that the total area of forest and woodland was 69 million and 157 million hectares respectively (RAC 1992). Australia has 155.8 million hectares of native forests, including 43.8 million hectares of closed forest and open forest and 112.0 million hectares of woodland (BRS 1998).

Some 22.3 million hectares of closed and open forest is either privately owned or leasehold while the balance is multiple use forest (11.0 million hectares), conservation reserves (8.4 million hectares) or other categories of public ownership (2.1 million hectares) (BRS 1998).

The multiple use forests are managed for sustainable wood production and the conservation of biological values and less than 1% of these forests are harvested in any one year. This small proportion is regenerated following harvesting so that a perpetual supply of native hardwood and softwood is available. The forests in conservation reserves are permanently reserved from logging.

Causes of extinction and past and present threats to endangered plant species

Cause of threat	Number of species presumed extinct Presumed Cause	Number of endangered species
Cause of threat	Number of species presumed extinct Presumed Cause	Past Threat	Present & Future Threat
Low numbers	-	10	85
Roadworks	1	8	57
Weed Competition	4	12	57
Grazing	34	51	55
Agriculture	44	112	50
Industrial & urban development	3	20	21
Fire frequency	-	10	17
Collecting	-	6	17
Mining	1	3	11
Forestry	-	10	10
Other threats	2	29	56
Source: Leigh and Briggs (1992)

Far from being the cause of extinction, logging or other forms of disturbance have a role in the regeneration of many plant species. The literature on disturbance of ecological systems is very large and Pickett and White (1985) concluded that:

There can be no doubt that disturbance is an important and widespread phenomenon in nature... Disturbance is common to many different systems. It functions or has functioned at all temporal and spatial scales and levels of organization of ecological and evolutionary interest.

The focus on extending the area of forest in reserves-often by people with real misconceptions about the importance of fire and disturbance in maintaining the existing ecosystems such as mountain ash forests-has led to other opportunities to conserve biodiversity being ignored.

Over two-thirds of Australia including both forest and non-forest ecosystems is managed by private landowners.

Private landowners could contribute significantly to the conservation of biodiversity over a wide range of habitats by, for example, reducing the use of flood irrigation to control salinity, rethinking the cattle and sheep stocking rates in Australia's rangelands and undertaking concerted programs to control feral animals. Furthermore, if the 11.3 million hectares of privately owned native forest were managed for commercial purposes the pressure to clear native forest to make way for other land uses would be reduced.

National programs such as Landcare, which are based on the principles of prevention, cooperation and inclusion, have produced outstanding results through stimulating community tree planting programs and reducing land degradation.

An approach similar to Landcare's needs to be taken to conserving biodiversity, which affects most facets of the Australian economy and lifestyle. The conservation of biodiversity should be strongly linked to the concept of ecologically sustainable development and not restricted to increasing the area of parks and reserves with little thought being given to their future management.

References
ABARE 1995, Quarterly Forest Products Statistics, Canberra, March quarter.

Leigh, J.D. and Briggs, J.H. 1992, Rare or Threatened Australian Plants, Australian National Parks and Wildlife Service, Canberra.

Pickett, S.T.A. and White, P.S. 1985, 'Patch dynamics: a synthesis', in Pickett, S.T.A. and White, P.S. (eds), The Ecology of Natural Disturbance and Patch Dynamics, Academic Press, Orlando, pp. 371-84.


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