Role of the coralline alga Halimeda gracilis Harvey ex. J. Agardh in sediment development at Minicoy Island (Lakshadweep) during monsoon months

Abstract

The green alga Halimeda is a producer not only of carbon but also of loose carbonate sediment that is important for the building of a reef. Borings through the lagoon floor carried out at Bikini, Enewetak and other atolls of the Marshall Islands indicated that Halimeda segments are a major constituent of many lagoon deposits. The aged, white segments are shed from the Halimeda thallus by a natural separation from the node. Eventually, by process of disintegration, cementation and recrystallization, they are bound with other reef organisms into carbonate rock. Halimeda gracilis is the abundant species found at Minicoy. It performs two important sedimentary functions.