Placement of Reef Balls in Ras Laffan Industrial City (Qatar) (Project Report 2003) Introduction Coral reefs, by the virtue of their efficient biological recycling, retention of nutrients and provision of sheltered habitat to a variety of aquatic organisms, provide one of the most diverse and biologically productive ecosystems. Reef building corals are calcium depositing animals building colonies for numerous microscopic organisms mainly polyps. Each polyps has living plant cells, inside them, and during day time these cells photosynthesise and produce by products which are consumed by corals as food. Polyps secrete calcium carbonate which provides shelter to polyps and add to the structure of the existing colony. Several algae species thrive in calcified environment providing additional binding and adding to the beauty of reefs. Coral reefs are very dynamic and fragile ecosystem, particularly vulnerable to extreme natural phenomenon and human activities. Corals have very specific environmental requirements such as light, temperature, water clarity, oxygen and salinity. Oceanographic features such as currents and wave actions also play a role on the life-cycle of corals. In Qatar, coral reefs are, shallow and of low diversity, found along the eastern coast. Coral reefs play an important role in the marine environment by providing nutrients, shelter and breeding grounds to various fish, shellfish (molluscs and crustaceans), turtles and algae. The major threats to corals include thermal discharges, oil spills, dredging and reclamation, anchoring of boats and activities causing silt dispersion. Ras Laffan Industrial City has initiated a coral protection programme which includes identification and assessment of the distribution of corals around Ras Laffan, and controlling industrial activities to minimize impacts on coral. Ras Laffan Industrial City (RLC) is situated on the Northeastern side of Qatar along the Arabian Gulf in the State of Qatar occupying an area of 106 km2 (Figure 1). Figure 1. Location of Ras Laffan..........