Fringing Reef - Species Diversity

Species Diversity

The backreef area has the least species diversity, which increases seaward towards the reef crest. Some of this difference is due to eutrophication from increased nutrients, sediments and toxicity due to domestic and industrial wastes.

More macrophytes live on the bottom due to the increases in nutrients. They also feel that this increase in nutrients has caused an increase in the number of phytoplankton that are present above the coral reef. The increase in phytoplankton has led to reduced light reaching the coral species and has also led to a greater number of larger invertebrates to be found.

The sediments that are present within the environment cause increased turbidity and may smother some organisms. The corals present on the fringing reefs use four processes to get rid of sediments which include polyp distension, tentacular movement, ciliary action and mucus production. The corals that are present then are thus likely those that can get rid of the sediments the best.

Brooding corals have higher growth and reproduction rates than others.

In the area of the reef closest to the shore there is generally a lot of fleshy algae which forms on sand and coral rubble. These types of algae include Lyngbia sp. and Oscilatoria sp.

Over recent years the dominant species in the reef flat have been affected by environmental changes. On fringing reefs in Barbados, species such as Diploria strigosa, Palythoa mamillosa, and Diadema antillarum are found.

The reef crest's most common species is Porites porites, although there are also significant areas covered in fleshy algae too.