11th ICRS Abstract book - Nova Southeastern University

Poster Mini-Symposium 4: Coral Reef Organisms as Recorders of Local and Global Environmental Change
4.71
Heavy Metal Contents in Growth Bands Of Porites Corals: Record Of
Anthropogenic And Human Developments From The Jordanian Gulf Of Aqaba
Saber AL-ROUSAN* 1 , Rashid AL-SHLOUL 2 , Fuad AL-HORANI 1 , Ahmad ABU-
HILAL 2
1 Marine Science Station, P.O.Box 195, The University of Jordan and Yarmouk
University, Aqaba, Jordan, 2 Department of Earth and Environmental Science, Yarmouk
University, Irbid, Jordan
In order to assess pollutants and impact of environmental changes in the coastal region of
the Jordanian Gulf of Aqaba, concentrations of six metals were traced through variations
in five years growth bands sections of recent Porties coral skeleton. X-radiography
showed annual growth band patterns extending back to the year 1925. Baseline metal
concentrations in Porites corals were established using 35 years-long metal record from
late Holocene coral (deposited in pristine environment) and coral from reef that is least
exposed to pollution in the marine reserve in the Gulf of Aqaba. The skeleton samples of
the collected corals were acid digested and analyzed for their Cd, Cu, Fe, Mn, Pb and Zn
content using Flame Atomic Absorption Spectrophotometer (FAAS). All metal profiles
(except Fe and Zn) recorded the same metal signature from recent coral (1925-2005) in
which low steady baseline levels were displayed in growth bands older than 1965, similar
to those obtained from fossil and unpolluted corals. Most metals showed dramatic
increase (ranging from 17 to 300 %) in growth band sections younger than 1965
suggesting an extensive contamination of the coastal area since the mid sixties. This date
represents the beginning of a period that witnessed increasing coastal activities,
constructions and urbanization. This has produced a significant reduction in coral skeletal
extension rates. Results from this study strongly suggest that Porites corals have a high
tendency to accumulate heavy metals in their skeletons and therefore can serve as proxy
tools to monitor and record environmental pollution (bioindicators) in the Gulf of Aqaba.
4.72
Study Of Heavy Metal Accumulation in Scleractinian Corls Of Viti Levu, Fiji
Islands
Sofia SHAH 1 , Edward LOVELL* 2
1 Chemistry/Marine Science, University of the South Pacific, Suva, Fiji, 2 Marine Science,
USP, SUVA, Fiji
The concentration of heavy metals (Copper, Lead, Zinc, Cadmium and Iron), together
with the partitioning of the metals in the skeleton, tissue and zooxanthallae have been
studied in three different coral families. The variation of metals in Acropora formosa,
Pocillopora damicornis and Porites spp was also looked into. Heavy metal accumulation
rates were studied for Acropora formosa and Pocillopora damicornis for a period of five
days. Study sites included Suva and Nukubuco reefs, Coral Coast and Dravuni.
High concentrations of metals were determined for the zooxanthallae, than the tissue and
the skeleton, suggesting that the zooxanthallae is responsible for the metal uptake in
corals. This was the case for nearly all the corals studied. There is variation in the
uptake of metals, suggesting that Porities spp seem to accumulate lower concentration of
the metals than Acropora or Pocillopora. Corals from Dravuni had lower metal
concentrations than that from the Coral Coast or the southern reefs, hence represents an
excellent reference site.
Dose response curves show that as the nominal concentration increases, the uptake by the
corals also increases. Two bioassays were carried out with nominal concentrations of 0,
0.01, 0.1 and 0.5 mg per litre of metal solution. Variations occurred for each dosage day.
High concentrations of Pb as well as Fe seem to be accumulated in the corals for each
dosage period, when compared to other metals. Pb and Fe concentrations as high as 2.5
and 0.8 ppm respectively had been transferred to the corals. There were significant
differences in the uptake of the metals (p