Bathymetric adaptations of corals at Davies Reef, Great Barrier Reef: Light saturation

Brief description

Corals were collected by scuba along 2 transects at Davies Reef in October 1980, and February, July and December 1981. Transect A-B ran from 1-17 m deep on the seaward margin of the reef flat. Transect C-D ran from 1-51 m deep on the seaward reef slope. Collection date, sea surface temperature, transect, depth and coral species were recorded.For the experiments, either a group of four 12 cm terminal branches of Acropora formosa or Acropora valenciennesi, or one 9 cm diameter colony of all other species were placed in a chamber and changes in dissolved oxygen content measured. Light measurements of photosynthetic photon flux density were in units of microEinsteins (400-700 nm) per square metre per second. Corals were incubated in the dark and light for periods of 20-30 min, arranged in order of increasing light intensity.The corals were frozen at the end of the experiment; chlorophylls and accessory pigments were extracted with 3 volumes of 20% tetrahydrofuran in methanol (v:v), separated and quantified by high performance liquid chromatography. Ten replicate coral samples were analysed for protein content. To establish:- whether photoadaptations occur in reef-building corals- whether photoadaptations occur as continuous gradients correlated to ambient light intensity- whether relationships between photoadaptations and ambinet light intensity can be mathematically described- whether corals from high/low light environments correspond to definitions of sun/shade plants Data analyses were part of a series of three papers addressing:1. Long-term growth responses (data not held by AIMS)2. Light saturation curves for photosynthesis and respiration3. UV-B absorbing compounds (see separate metadata record)

Lineage

Maintenance and Update Frequency: notPlanned

Notes

Credit
Chalker, Bruce E, Dr (Principal Investigator)

Credit
Dunlap, Walter C, Dr (Custodian)