what is likely to happen in the future?
"One hundred years ago, many countries had reefs like the Great Barrier Reef. They probably thought they were robust and weren't going to fall over, but, of course, they did. The Great Barrier Reef is a reminder of what's at stake."
-Ove Hoegh-Guldberg
Director of the University of Queensland's Global Change Institute
It is likely that the Great Barrier Reef will continue deteriorating despite measures taken to protect it (such as increasing the highly protected areas from 4.6% of the park to 33.3%). There are some signs of progress which is encouraging, but more needs to be done before the Great Barrier Reef can start recovering.
TABLE WITH DATA
Positive:
Negative:
- 20% of sugar cane growers, 11% of graziers, 18% of horticulture producers have adopted better management practices.
- Thus, the average annual amount of pollutants entering the reef have decreased: nitrogen by 4%, phosphorus by 2%, sediment by 2% and pesticides by 8%.
Negative:
- Seagrass has received a poor score as it has been on the decline for the past 4 years
- In the Burnett Mary and Fitzroy regions of Queensland had large amounts of discharge in 2009-2010
- Wetlands and riparian indicators were poor in Burnett Mary because of conversion of swamps to urban and agricultural usage (3)
DATA ON PROBLEMS THE GREAT BARRIER REEF FACES
ocean acidification & calcification
Because of of the increased emissions of carbon dioxide, there is more CO2 entering the oceans. A chemical reaction between the ocean water and the carbon dioxide results in carbonic acid. Since the Industrial Revolution, about 40% of the CO2 that humans have produced has entered the ocean waters, which has caused the ocean acidity to lower by 0.1 on the pH scale. The level of carbonate ions has also decreased by 15-20%.
Carbonate ions are essential in coral reef calcification, so reef building and calcification decrease as the carbonate ion concentrations decrease.
A study by the Australian Institute of Marine Science discovered that long-lived corals were calcifying 15% less than in 1990. According to their study, this has never happened in the past 400 years of the coral reef's history. (1)
Table 1
Carbonate ions are essential in coral reef calcification, so reef building and calcification decrease as the carbonate ion concentrations decrease.
A study by the Australian Institute of Marine Science discovered that long-lived corals were calcifying 15% less than in 1990. According to their study, this has never happened in the past 400 years of the coral reef's history. (1)
Table 1
Warmer Waters
Warm water temperatures cause the zooxanthellae that live in the corals to leave. This phenomenon is called "coral bleaching", because the empty corals become white.
As our water continues to warm, more zooxanthellae continue to leave causing mass bleaching. In 1998, a worldwide bleaching occurred where 16% of the earth's coral systems died. (1)
Table 2
Agriculture
Agriculture has negative effects on the coral reefs, and as shown through the graph on the left, it continues growing in Australia.
Some models estimate that 22% of the world's coral reef system is threatened by land-pollution (fertilizers, pesticides, sewage, sediments from coastal development, herbicides, etc) (2)
80% of the land adjacent to the Great Barrier Reef is farm land that support various agricultural activity such as sugar cane cropping and cattle grazing,
Table 3
Some models estimate that 22% of the world's coral reef system is threatened by land-pollution (fertilizers, pesticides, sewage, sediments from coastal development, herbicides, etc) (2)
80% of the land adjacent to the Great Barrier Reef is farm land that support various agricultural activity such as sugar cane cropping and cattle grazing,
Table 3
The runoff from farm nutrients, pesticides and sediments can have detrimental effects on the Great Barrier Reef. An experiment done by the Australian Institute of Marine Science showed that in areas far from farm lands, the hard coral biodiversity was almost double that of the areas close to agricultural areas. (2)
Table 4
coastal development
21 local governments are adjacent to the Great Barrier Reef, and growth is predicted for urban areas in the coastal region.
Human activities such as mining or building can lead to negative effects for the coral reef. For example, industrial pollutants and sewage become runoff which degrades the water quality of the Great Barrier Reefs waters. (2)
Table 5
Human activities such as mining or building can lead to negative effects for the coral reef. For example, industrial pollutants and sewage become runoff which degrades the water quality of the Great Barrier Reefs waters. (2)
Table 5
Sources:
(1) "Climate Change Science Fact Sheet." Climate Scientists Australia. Climate Scientists Australia, May 2010. Web. 22 Nov. 2013. <http://climatescientistsaustralia.org.au/assets/files/csa_gbr-factsheet_may10.pdf>.
(2) "Human Impact on the Great Barrier Reef: Pollution." University of Michigan. University of Michigan, n.d. Web. 21 Nov. 2013. <http://sitemaker.umich.edu/gc2sec7labgroup3/pollution>.
(3) "Great Barrier Reef-wide Summary." Reef Water Quality Protection Plan. Australian Government, 18 Apr. 2013. Web. 24 Nov. 2013. <http://www.reefplan.qld.gov.au/about/regions/great-barrier-reef/gbr-second-report-card.aspx>.
Header Image: http://divezone.net/best-great-barrier-reef-australia-liveaboard-reviews-2013
Table with data: http://www.reefplan.qld.gov.au/about/regions/great-barrier-reef/gbr-second-report-card.aspx
Table 1&2: http://climatescientistsaustralia.org.au/assets/files/csa_gbr-factsheet_may10.pdf
Table 3, 4 & 5: http://elibrary.gbrmpa.gov.au/jspui/bitstream/11017/358/1/GBR-water-quality-current-issues.pdf
Table 6: http://www.dsdip.qld.gov.au/resources/plan/gbr-economic-analysis.pdf
(1) "Climate Change Science Fact Sheet." Climate Scientists Australia. Climate Scientists Australia, May 2010. Web. 22 Nov. 2013. <http://climatescientistsaustralia.org.au/assets/files/csa_gbr-factsheet_may10.pdf>.
(2) "Human Impact on the Great Barrier Reef: Pollution." University of Michigan. University of Michigan, n.d. Web. 21 Nov. 2013. <http://sitemaker.umich.edu/gc2sec7labgroup3/pollution>.
(3) "Great Barrier Reef-wide Summary." Reef Water Quality Protection Plan. Australian Government, 18 Apr. 2013. Web. 24 Nov. 2013. <http://www.reefplan.qld.gov.au/about/regions/great-barrier-reef/gbr-second-report-card.aspx>.
Header Image: http://divezone.net/best-great-barrier-reef-australia-liveaboard-reviews-2013
Table with data: http://www.reefplan.qld.gov.au/about/regions/great-barrier-reef/gbr-second-report-card.aspx
Table 1&2: http://climatescientistsaustralia.org.au/assets/files/csa_gbr-factsheet_may10.pdf
Table 3, 4 & 5: http://elibrary.gbrmpa.gov.au/jspui/bitstream/11017/358/1/GBR-water-quality-current-issues.pdf
Table 6: http://www.dsdip.qld.gov.au/resources/plan/gbr-economic-analysis.pdf