Читать книгу Diving Indonesia Periplus Adventure Guid онлайн

65 страница из 170

Massive forms. In general, massive, boulder-like forms grow in shallow water where light is plentiful, and along the reef edge where the current is strong. These include the common Monastrea, Pocillopora, and Pontes. In the shallow, often turbid water of the back reef, the more robust branching forms (Acropora) can out-compete the massive forms, which are more vulnerable to siltation.

Massive corals sometimes form "micro-atolls" in relatively calm backreefs and reef flats. These are flat-topped forms in which the center has been killed by excessive siltation or regular exposure by low tides. The sides continue to grow outward, demonstrating Darwin's theory in miniature.

Goniopora is an unusual massive coral that extends its polyps during the day. These are also usually large, reaching 20-30 centimeters in length. The effect is of a round stone, covered with little brown flowers.

Branching forms. Deeper in the reef, or in protected parts of the shallows, the diver will encounter finely branched and "leafy" forms. These more delicate structures cannot withstand strong wave action, and the added surface area of their shapes serves to better expose their zooxanthellae to the diminished sunlight of deeper waters.