The Cold Water Coral Research by bathymetry, acoustic geophysical and methane data, Santa Maria di Leuca, Northern Ionian Sea ˇV Apulian continental slop
Speaker: Kuan-Ting Lin
Abstract
The coral reef is a very important and one of the most diverse ecosystems on Earth. Corals mostly live in the tropical zone where the seawater temperature is higher than 20 degrees Celsius. They live on water depths no more than 50 meters to catch enough sunlight for the algae inside the coral to do the photosynthesis. There are some corals that live in the deeper and colder seawater called ˇ§cold water coralsˇ¨. People are curious about how the cold corals survive in the cold water and deep seafloor where there is almost no sunlight. Because the location is too far from the sea surface, this study use multi-beam bathymetry, acoustic geophysical and methane data collected onboard the survey vessel or by deep-towed instruments to analyze the environment. They found out that the living coral frameworks were located along large topographic highs facing the main currents, where hard substrata occurred. The cold water corals mainly grew on mound-like features located between 600 to 900 m water depth. The development of the coral colonies are not attributed to the seeping fluids such as methane because there are only weak methane anomalies were detected in the seawater and no direct expressions of gas seepage were observed. The occurrence of cold corals is most likely due to physiographic position and exposure to nutrient-rich currents.
Reference
A. Savini, C. Corselli, High-resolution bathymetry and acoustic geophysical data from Santa Maria di Leuca Cold Water province (Northern Ionian Sea ˇV Apulian continental slope), Deep-Sea Research II 57 (2010) 326-344.
G. Etiope, A. Savini, N. Lo Bue, P. Favali, C. Corselli, Deep-sea survey for the detection of methane at the ˇ§Santa Maria di Leucaˇ¨ Cold-water coral mounds (Ionian Sea, South Italy), Deep-Sea Research II 57 (2010) 431-440.