Biodiversity Theme Report
Australia State of the Environment Report 2001 (Theme Report)
Prepared by: Dr Jann Williams, RMIT University, Authors
Published by CSIRO on behalf of the Department of the Environment and Heritage, 2001
ISBN 0 643 06749 3
Biodiversity Issues and Challenges
This section considers each of the 65 biodiversity indicators outlined by Saunders et al. (1998) (Table 5). Where available, major supporting data, tables and figures are provided for these indicators, and details given for the key biodiversity issues and challenges facing Australia. The section is grouped into major areas: disturbance regimes and biodiversity, exotic species and GMOs and protecting biodiversity. Several key issues are examined in each major area and the relevant indicators explored.
Disturbance Regimes and Biodiversity
This section reports on the following environmental indicators, which are defined in Saunders et al. (1998).
| Environmental Indicator | |
|---|---|
| BD 1.1 | Human population distribution and density |
| BD 1.2 | Change in human population density |
| BD 2.1 | a | b | c | | Extent and rate of clearing or major modification of natural vegetation or marine habitat |
| BD 2.2 | a | b | c | | Location and configuration or fragmentation of remnant vegetation and marine habitat |
| BD 5 | Pollution |
| BD 6 | Areal extent of altered fire regimes |
| BD 7 | Human-induced climate change |
| BD 8.1 | a | b | | Lists and numbers of organisms being trafficked and legally exported |
| BD 8.2 | a | b | | Number of permits requested and issued for legal collecting or harvesting by venture |
| BD 8.3 | Proportion of numbers collected over size of reproducing population |
| BD 8.4 | Ratio of bycatch to target species |
| BD 12 | Integrated bioregional planning |
| BD 13.1 | Extent of each vegetation type and marine habitat type in protected areas |
| BD 13.2 | a | b | | Number of protected areas with management plans |
| BD 17.1 | a | b | | Number of management plans for ecologically sustainable harvesting |
| BD 17.2 | Effectiveness of bycatch controls |
| BD 18.1 | Area of clearing officially permitted |
| BD 18.2 | Area cleared to area revegetated |
| BD 20 | a | b | c | | Control over the impacts of pollution |
| BD 21 | Reducing the impacts of altered fire regimes |
| BD 22 | Minimising the potential impacts of human-induced climate change on biodiversity |
Human population growth and density
Changes in human population [BD Indicators 1.1 and 1.2]
The relationship between human population and the environment, including biodiversity, is complex. The total environmental effect of a human population is a function of the nature of the environment or resource in question, which is highly variable, and a range of factors that determine the per capita environmental effect of each person (Dovers 1997b). These factors include resource consumption, waste production, recreational activities and other direct interactions (e.g. spread of weeds), management or regulatory regimes for land use and the remedial strategies in place.
Human populations in 1997 by IBRA region (Figure 5) and projections for change in population density through to 2006 (Figure 6) show that the pattern of human settlement in Australia is characterised by high rates of urbanisation, low-density cities and the concentration of the population within 50 km of the coast, mainly between Melbourne and Brisbane in south-east Australia and in south-west Australia. In Antarctica, the total Australian population is around 300 people in summer and 75 in winter. The Human Settlements Report describes human population patterns in considerable detail. The focus here is on the potential effects of settlements on biodiversity.
Figure 5: Human population density in Australia in 1997 showing the concentration of Australians in coastal, urban areas.
Figures derived from ABS projections. Each dot equals 1000 people.
Source: ABS Statistical Local Area-based projections. Compiled by the Environmental Information Resources Network
Figure 6: Projected change in human population density by IBRA region, between 1997 and 2006. The main increases are expected in the coastal regions of southern and eastern Australia.
Units are persons per square kilometre.
Source: derived from the ABS, Statistical Local Area-based projections for 1997. Compiled by the Environmental Information Resources Network
Regions where population growth might increase pressure on biodiversity will depend on the resilience of regional environments and the management (or lack thereof) of the activities of the human population. Considering other indicators reported on in this report, pressures on biodiversity may be exacerbated by growth in human population in several coastal bioregions, especially in southern and eastern Australia. Population decline, such as is occurring in many Australian localities, may also influence biodiversity through a lessened ability to monitor or manage the environment.
Although the generation of population projections by IBRA is useful, population effects are not contained within such boundaries. Flows of people and the associated effects occur across bioregional (and other) boundaries, such as through both domestic and international tourism, the extraction or use of natural resource for consumers elsewhere (e.g. transport corridors or air or waterborne wastes). Such interregional flows of people and their effects on biodiversity point to the need for integrated approaches between different levels of government and other stakeholders, and of the need to incorporate biodiversity considerations into, for example, land use planning and transport policy.
Some people believe, on environmental grounds, that Australia's current human population (estimated as 19.4 million in August 2001) is too high. Others believe that the environmental effect of population growth can be managed. However, population is a complex, cross-sectoral issue and it is likely that the situation varies across different parts of Australia. Although population and settlement issues are managed to an extent through state, territory and local government planning, there is a strong case for national-scale coordination and development in order to consider the possible effects of population change for issues such as biodiversity.