Module 1
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OHT 2A
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The State of the Coastal and Marine Environment A
Source: Adapted from Department of the Environment, Sport and Territories
(1995) Our Sea, Our Future: Major Findings of the State of the
Marine Environment Report for Australia, Great Barrier Reef Marine
Park Authority, Canberra, pp. 96-103. |
The state of the marine environment is : "Generally good
but ...
- About seven billion tonnes of debris enters the world's
oceans each year (48-49% of this is plastic).
- Intertidal rocky shore habitats are potentially vulnerable
to human impacts, including over-harvesting of molluscs, crustaceans
and sea urchins for food and bait; trampling by fishers and other visitors;
and oil slicks and other pollutants which float on the surface.
- Unnaturally high levels of sediments and nutrients
have led to an alarming decline in seagrass beds in temperate Australia.
In Victoria, for example, around 85% of the total biomass of seagrass
in Western Port has been lost.
- Blooms of toxic marine algae, probably introduced from
other countries in ships' ballast waters, are now a serious periodic
problem in parts of Tasmania and Victoria where they kill marine life
and cause the closure of shellfish farms.
- Northern Australia has the world's last significant
population of tropical dugong (sea cow). The dugong is listed by the
IUCN as 'Vulnerable to Extinction' but is not listed under the Commonwealth
Endangered Species Protection Act.
- One of the most serious causes of declining water quality
in Australia's marine environment stem from poor catchment use.
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