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Pressures on Australia's land resources
14.20 LAND TENURE(a)
Australia's agricultural lands previously supported ecosystems of native vegetation, and significant changes to vegetation cover have occurred since European settlement. Clearing of native vegetation and replacement with pastures and crops continues today, and trends show a recent increase in land clearing. Estimates of annual clearing rates from the National Greenhouse Gas Inventory (table 14.21) show a decrease in total area cleared per year between 1971-1980 and 1981-1990 (average of 1.47 million and 551,000 hectares per year respectively). Annual clearing rates for Australia continued to decline in the 1991-1995 period, but rates have increased again over recent years. This has been due mainly to increased rates of clearing in Queensland.
Between 1971 and 1995, the estimated annual rate of clearing in Queensland fell. Between 1996 and 1999, however, the annual rate of land clearing in Queensland increased when compared to rates estimated for 1991-1995. The rate of land clearing in New South Wales also increased in the late nineties (1996-1999). Western Australia recorded a fall in the rate of land clearing for the same period.
Associated with the loss of native vegetation are a broad range of social, economic and environmental impacts. Social impacts can include loss of heritage values and loss of recreation and tourist values. Economic impacts can include costs associated with loss of flood control, deterioration of water quality, loss of habitat for economically important species, loss of tourist and bio-medical potential, and loss of production through soil degradation. Environmental impacts can include habitat loss or fragmentation, loss of ecosystem, species and genetic diversity, reduced water quality in inland and marine environments, reduced carbon storage, loss of heritage values and soil degradation (Higgins 2001). Socioeconomic benefits from clearing are derived from employment and income generated by the economic activity that occurs on the cleared land. These benefits provide strong incentives for landholders to clear the land.
Australia is covered by old, shallow soils. Agricultural activities and vegetation clearance often result in damaged soil structure and depleted soil nutrients, which can lead to losses in agricultural productivity and declines in the health of native animal and plant populations. Three types of soil degradation - salinity, sodicity and acidity - have been estimated to cost the Australian economy $2.4b annually (CRC for Soil and Land Management 1999).
Removal of deep rooted native perennial plant species and replacement with shallow rooted annual crops and pastures have changed the hydrological cycle (ABS 1996). Over time this has brought the water table closer to the surface, bringing with it dissolved salts that then become concentrated at the soil surface, in a process referred to as dryland salinity. Australia has an estimated 2.5 million hectares of land affected by dryland salinity (representing 0.6% of agricultural land). An estimate of the area with high potential to develop salinity is around 5.6 million hectares or 1.2% of agricultural land. By 2050 it is projected that this figure could rise to 17 million hectares (NLWRA 2001). These salt concentrations have a negative impact on a variety of social, ecological and economic processes.
Damage to buildings, roads, bridges and sewerage lines is expected from the effects of dryland salinity. An estimated 19,000 kilometres of Australia's roads were recorded as being affected by dryland salinity in 2000. Projections for WA, SA, Victoria, NSW and Queensland show that this figure is expected to increase more than three-fold by 2050 (to 67,400 kilometres). Reduction of diversity of native species is also expected, with at least 1,500 plant species expected to be harmed by dryland salinity in Western Australia; 450 of these are at risk of extinction (NLWRA 2001). It is projected that 130 important wetlands (including Ramsar wetlands) will be at high risk from shallow water tables by 2050 (table 14.22).
Salinity has negative effects on agricultural yields and slows growth rates of broadacre crops. In terms of value of production forgone, costs of dryland salinity are in the range of $130m to $330m per year (MDBC 1999; CRC Soil and Land Management 1999). The variation between these two estimates reflects the different valuation methods used to determine the cost of production forgone as well as the damage to public and private infrastructure.
Sodic soils occur naturally across one-third of Australia (CRC for Soil and Land Management 1999). A soil is classed as sodic when the level of exchangeable sodium (Na) exceeds 6% and begins to affect the soil structure. Sodicity degrades a soil's properties by making it more erodible, restricting water entry and reducing the ability of the soil to conduct water (Charman & Murphey 1991). Sodicity is often found in conjunction with other land degradation problems such as waterlogging and gully erosion. Net production loss as a result of a lack of amelioration through the addition of gypsum has been estimated to cost Australia $1.3b per year (CRC for Soil and Land Management 1999).
Many Australian soils are also naturally acidic. The application of acidic nitrogen fertilisers or the growing of sub-clover pastures can, however, increase soil acidity. This form of degradation is exacerbated in areas where soils are sandy and rainfall is below 500 mm per year. Around 35 million hectares of Australian soils are considered highly acidic. More than 55 million hectares are moderately or slightly acidic (pH Ca 4.9-6.0) and appear to have the potential to degrade to highly acidic conditions (pH Ca <4.8) (LWRRDC 1995). Acidification can lead to soil infertility problems which are expensive to reverse. The 92 million hectares of acid soils that occur in Australia's high rainfall agricultural lands are estimated to cost the economy over of $630m per year in agricultural production (CRC for Soil and Land Management 1999).
Response to land degradation
A variety of government initiatives have attempted to restore degraded areas. One such initiative has been the Landcare program. This began as a partnership between the National Farmers' Federation (NFF) and the Australian Conservation Foundation (ACF) in 1989. The Government declared the 1990s the 'Decade of Landcare', for which expenditure has amounted to over $1b (Reeve 2001). A survey of members of farmer organisations and rural addressees indicates that membership in landcare has increased substantially in the last ten years (graph 14.23).
Landcare group membership increased between 1991 and 2000 for all States, the total Australian membership increasing from 23% to 43%. In 2000 Western Australia had the highest rate of membership (69%), followed by Victoria and Tasmania (53% in both States). Between 1991 and 2000 membership in Tasmania increased by 37%.
In 1997 the ABS asked agricultural landholders if they had changed their farming practices for conservation reasons and from whom they received the most support in implementing these changes. Responses indicated that a high proportion received support from family (17%). Relatively few farmers cited government agencies and land management groups as providing the most support (3% and 1% respectively).
Some 43 million trees were reported to have been planted on farms in 1999-2000 on around 150,000 hectares (table 14.24). (This result should be interpreted cautiously owing to high variability in responses, possibly due to difficulties in attributing tree plantings to specific purposes, and high sampling errors.) Around one-third of the number of trees planted in 1999-2000 were for wood or pulp production, but accounted for only about 10% of the area planted. Around 28 million trees were planted on around 140,000 hectares for purposes including nature conservation, protection of land and water, fodder and oil plants and enhanced agricultural production (windbreaks, shade trees, etc.).
Tree planting data were also collected in 1996-97 and 1998-99. In 1996-97 around 32 million trees were reported to have been planted, and the figure increased to around 51 million trees in 1998-99 (table 14.24). There has been some debate in recent times regarding the effectiveness of tree planting as a measure to ameliorate land degradation.
14.24 TREES PLANTED(a)
Tourism as a land use
Tourism is a growing industry in Australia, and accounted for 4.5% of Australia's GDP in 1997-98 (compared with a 3% contribution from the agricultural sector) (ABS 2001). Tourist activity, like any land use, brings with it a variety of impacts on the environment. These impacts can be exacerbated when the activity takes place in natural areas or areas dedicated to ecosystem protection.
Australia's unique and diverse natural environments are attracting an increasing number of domestic and international visitors, with nature-based tourism, particularly eco-tourism, representing an important growth segment of Australia's tourism market. National parks are popular nature-based attractions, with around half of all visitors to Australia in 1995 visiting at least one during their stay (1,699,500 visitors). A 1999 Bureau of Tourism Research (BTR) survey showed that of all international holiday visitors to Australia, 69% went to the beach, 58% visited a national park or went bushwalking (table 14.25), and 37% of holiday visitors were influenced to visit Australia by its nature, landscapes and wildlife (BTR 1999). International visitors from Canada and Other European Countries had the highest proportion of people visiting national parks, bushwalking or going on rainforest walks. Travellers from Germany and The United Kingdom recorded the highest rates of international visitors going to the beach (76%).
14.25 INTERNATIONAL VISITORS(a), By Reason for Travel and Nature of Leisure Activities - 1999
Pressures associated with tourism
National parks and conservation reserves were established to protect scenic or popular recreational locations, geological oddities and historical sites (CSIRO 2000). As land was subjected to agricultural pressures and native species became rarer, efforts were made to protect remaining species and bushland. Increased desire for recreational opportunities in these remnants led to concentrated tourist activities. This can conflict with the original purpose of the conservation area and destroy the qualities that initially attracted tourists to the area. Like any other type of urban growth, tourist developments can impact on biodiversity as they often take place in sensitive ecosystems, on floodplains or close to beaches (SoE 1996). Some examples of environmental impacts associated with tourism are: the introduction of exotic species; barriers to wildlife migration; vandalism; soil compaction and erosion; and destruction of wildlife and wildlife habitat.
Protecting natural heritage
Various conservation mechanisms have been developed by the Commonwealth Government and the State and Territory Governments aimed at protecting areas of significant natural heritage value from pressures such as those mentioned. Conservation reserves are a central mechanism with, as indicated earlier, around 524,100 square kilometres of Australia's land in public conservation reserves in 1993 (see table 14.20). An additional 10,800 square kilometres were in Aboriginal Freehold National Parks. Another mechanism is the Commonwealth Government's Register of the National Estate, a list of that includes 2,163 natural environments, and 9,808 historical and 911 cultural heritage places throughout Australia (AHC unpub.).
World Heritage areas
Natural and cultural sites of 'outstanding universal value' may be entered on the list compiled by the World Heritage Committee. In addition to their intrinsic conservation value, World Heritage places are economically important because of their attraction as tourism sites. Inclusion on the list signifies that there is a legal obligation on the world community to protect, conserve and present the property for the benefit of current and future generations (SoE 1996). World Heritage listing does not prevent existing land use activities from taking place, as long as they do not threaten the natural and cultural values of the property. As at December 2000 there were 690 places listed on the World Heritage List. Australia has 14 of these (table 14.26), the last added in November 2000.
14.26 WORLD HERITAGE SITES, Australia - 2000
Management of Indigenous land and cultural heritage
Indigenous cutural heritage is widespread throughout the lands and waters of Australia (AHC 2001). Indigenous peoples also have strong practical and economic links with country through ongoing use of bush tucker and other forms of land use, such as mining (Vardon et al. 1997). The rights and interests of Indigenous peoples in relation to cultural heritage and links to country derive from customary law, original ownership, developing Indigenous traditions and recent history (AHC 2001). As such, Indigenous people are important land managers in Australia.
One institutional arrangement which recognises the important role Indigenous peoples play in managing land is joint management of protected areas. Joint or co-management of the World Heritage listed Kakadu National Park began in 1978. Joint management refers to a management model in which social and cultural values of parks are considered, as well as that of their ecological value, through shared decision-making between local people who use the park and formally trained managers (Cowell et. al. 1998). Jointly managed parks feature a board of management that comprises a majority of traditional owners or their Aboriginal representatives (EA 2001b). They are also Aboriginal places that are leased back to the Commonwealth for a defined period (usually 99 years) for management as a national park. The success of joint management in Kakadu led to similar management approaches being adopted in other parks such as Uluru-Kata Juta National Park, also in the Northern Territory, and Booderee National Park in the Jervis Bay region.
Participation of Indigenous peoples in environmental management of protected areas is an evolving process, and various models of co-management and joint management have been implemented. At March 2001 there were 13 Indigenous Protected Areas covering over 3.1 million hectares (EA 2001b). These differ greatly in size, ranging from 32 hectares (Oyster Cove in Tasmania) to 1.28 million hectares (Watarru in the Great Victorian Desert region of South Australia) (table 14.27).
14.27 DECLARED INDIGENOUS PROTECTED AREAS - June 2001