Factors influencing the Region’s values
6.7 Assessment summary — Factors influencing the Region’s values
Section 54(3)(g) of the Great Barrier Reef Marine Park Act 1975 requires ‘… an assessment of the factors influencing the current and projected future environmental, economic and social values…’ of the Great Barrier Reef Region. Regulation 116A(2)(e) of the Great Barrier Reef Marine Park Regulations 1983 requires ‘… an assessment of the factors influencing the current and projected future heritage values…’ of the Great Barrier Reef Region. The assessment is based on four assessment criteria: • impacts on ecological values • impacts on heritage values • impacts on economic values • impacts on social values.
6.7.1 Impacts on ecological values
Outlook Report 2009: Assessment summary Climate change, particularly rising sea temperatures and ocean acidification, has already affected the Great Barrier Reef ecosystem and over the next 50 years it is likely to significantly affect most components of the ecosystem. The Great Barrier Reef, especially much of its inshore area, is being affected by increased nutrients, sediments and other pollutants in catchment runoff, mainly from diffuse agricultural sources, despite recent advances in agricultural practices. Coastal development is contributing to the modification and loss of coastal habitats that support the Great Barrier Reef. As the coastal population continues to grow there will be increasing use of the Great Barrier Reef and therefore the potential for further damage. Direct use of the Region is impacting on some environmental values. Current summary and assessment components Assessment grade and trend Confidence
Impact on ecological values: Climate change has already affected the Great Barrier Reef ecosystem. Its effects are compounding the ongoing impacts from land-based run-off and coastal development, particularly loads of sediments and nutrients entering the Region and the modification of supporting coastal habitats. Direct uses contribute to a range of impacts; most are localised. Economic and population growth will likely mean more use of the Region, increasing the likelihood of impacts. The combined influence of the four factors Very low Low is concentrated in inshore central and southern areas. impact impact Climate change: Climate change is predicted to continue to have far-reaching consequences for the Reef ecosystem and over the next 50 years it is likely to significantly affect most components. Future predictions indicate sea level rises and temperature increases will continue, the pH of the ocean will gradually decline and weather will be more severe. Coastal development: Modification of terrestrial habitats that support the Great Barrier Reef is likely to continue based on the projected changes in the catchment. Changes to coastal habitats and reductions in connectivity affect the Region’s ecosystem. Land-based run-off: Inshore areas are particularly at risk from poor water quality. Agricultural practices in the catchment are improving and there have been reductions in the nutrient, sediment and pesticide loads from the catchment entering the Region. There is likely to be a significant lag before water quality improvements are measured in the Region. Marine debris continues to affect the ecosystem — including species of conservation concern. Direct use: Fishing continues to affect the Region’s values such as through discarded catch; incidental catch of species of conservation concern; overfishing and illegal fishing. Increasing port activities directly affect local areas; uncertainty remains around ecosystem effects. Increasing regional populations and economic development will likely increase direct use and therefore the likelihood of impacts. Grading statements Very low impact
Some minor impacts have already been observed and there is concern that, based on accepted predictions, there will be significant but localised impacts on the Region’s ecological values.