The role of maximum shelf depth versus distance from shore in explaining a diversity gradient of mushroom corals (Fungiidae) off Jakarta
Hoeksema, B.W.; Giyanto; Suharsono (2019). The role of maximum shelf depth versus distance from shore in explaining a diversity gradient of mushroom corals (Fungiidae) off Jakarta. Diversity 11(3): 46. https://dx.doi.org/10.3390/d11030046 In: Diversity. MDPI: Basel. ISSN 1424-2818; e-ISSN 1424-2818, more | |
Keywords | | Author keywords | mega city; river outlets; water transparency; blast fishing |
Authors | | Top | - Hoeksema, B.W., more
- Giyanto
- Suharsono
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Abstract | Many coral reef systems are shelf-based and consist of reefs that are arranged in rows parallel to the coastline. They usually show an increase in species richness in the offshore direction, coinciding with decreasing terrigenous impact and a deeper seafloor. These two conditions usually concur, which makes it less easy to distinguish how each of them influences coral diversity separately. Since reefs off Jakarta (in the Thousand Islands archipelago) are arranged in an 80 km long string perpendicular to the coastline in south-to-north direction, with a maximum shelf depth halfway along (instead of at the end of) the string, this archipelago is very suitable for studies on inshore–offshore gradients. In the present study, mushroom corals (Fungiidae; n = 31) were used to examine diversity patterns on 38 reef sites along such a gradient, involving species richness over their entire depth range from reef flat to reef base (2–30 m) and separately at shallow depths (2–6 m). Total species diversity was highest in the central part of the archipelago, with unique species occurring in deep habitats. Diversity at shallow depths was only slightly higher here than at reefs located more nearshore and offshore, which both had less clear water. Therefore, shelf depth and distance from the mainland can be considered separate determinants of coral diversity off Jakarta. |
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