Reef Report for Friday, February 23, 2007
Recent Research Shows Connection between Coral Reefs and Adjacent Land-Based Activities
This past week three separate news items pointed to the connection between coral reefs and the activities that take place on nearby lands. The research points out that activities on land may have an impact on coral reefs that lie miles offshore, and that care must be taken with farming, ranching, construction, and other activities.
The first article we spotted in Perth Now, which reviewed the scientific research of Dr. Arnold Dekker, whose specialty is remote sensing. In this article Dr. Dekker had noticed a large plume of sediment from several rivers that empty into Princess Charlotte Bay extending out to the reef.
In this particular case the images were taken by satellite in mid February of an area near Prince Charlotte Bay, which is several hundred kilometers north of Cairns. In January between 30 and 40 cm of rain fell in this area, followed by another 12-20cm of rain in February.
The plume clearly demonstrates the certain connection between land and reef. What is not mentioned is that the area being drained by these rivers is very remote wild lands, consisting of Lakefield National Park, and a network of cattle stations. Very little crop agriculture happens in this very sparsely inhabited area.
Another news item points to the potential harm that runoff from farms could have on coral reefs. In this article from the Herald Sun, Dr Andrew Negri, a lead scientist from the Australian Institute of Marine Science, and his team described their research on the toxicity of various agricultural chemicals (pesticides and fungicides) or the various life stages of corals.
Their research indicated that early larval stages of corals are very sensitive to agricultural chemicals, and that the presence of Ag chemicals in plumes extending to coral reefs could disrupt the natural reproductive processes of corals.
It also points to the wisdom o the current The Great Barrier Reef Marine Park Authority which is currently overseeing the implementation of the 10-year $40 million Reef Water Quality Protection Plan to improve land management practices in the land areas that drain into the waters adjacent to the Great Barrier Reef.
Finally thereís a recent article from the Whitsunday Times, which points to recent news of high silt levels washing off into the bay, most of thought to be from recently started construction products.
Any land-based activity that disturbs soil, be it farming, construction, or grazing, has the potential to harm adjacent coral reefs. Minimizing that impact is important and we are glad for the number of farmers, ranchers, and concerned citizens here in Australia that see the connection between land and ocean, and work to minimize these impacts. Thatís not yet a universal value here in Australia, or elsewhere in the world, and we hope to see the values of good stewardship spread.
More more about Dr. Negriís research.
The weekly reef report is written by Joel Groberg of DiveTheReef.com,
who compiles them from the many conversations he has with dive staff in the area, as well as† many other local sources in the dive
Index of all reef reports.