Reef Lime Constructions

Abstract

The lime construction forms the structural basis of the coral reef ecosystem. It provides optimal disposition for sessile phototrophic organisms in the field of light. It presents refuge for the vagile fauna saving it from being grazed. It also forms the fortress that defends the reef biota from the destructive action of hydraulic stress by waves and currents. This construction is created largely by the hermatypic calcareous organisms — animals and plants, which extract carbonates from surrounding sea waters for building up their exoskeletons, shells, spicules or other calcareous elements of their bodies. The form and shape of the reef constructions themselves are largely resulting from the interaction of communities of sedentary hermatypic organisms with the hydrodynamic stress, which in the tropical zone has usually some definite direction (Heckel 1974). Therefore, in spite of a great morphological variety of reefal constructions they have many common geomorphological elements, such as buttress system, reef-flat, lagoon, patch reef zone etc. It demonstrates the existence of some common regularity in their origin and growth on different structural foundations of shelf and island coasts, situated in different parts of the tropical zone. This regularity was first recognized by Charles Darwin (Darwin 1842).