Status of Coral Reef Communities on Two Carbonate Platforms (Tun Sakaran Marine Park, East Sabah, Malaysia)

Table 2

Description of the three radial lines on the three sites, Gaya West, Gaya East, and Mantabuan, from the lagoon to the reef rim and the outer slope.

(a)  

Gaya West	Depth, turbidity, and currents	Description of the general morphology
The mesh reef in the lagoon (stations GW1 to GW5)	Depth: −7 m.; The water is very turbid.; Current speed is low.	In the lagoon, corals form a mesh reef made of large coral strips, 4–7 m high and 4-5 m wide. These coral rims rise from the seabed like large walls, surrounded by a sandy plain (Figure 5). The upper part of the strips never emerges at low tide. Coral vitality is low.
The transition from the lagoon to the reef rim	Depth: −2 m.; It is possible to walk on this part of the reef at low tide.; Currents are very strong, and,as a consequence, the area has not been analyzed.	From the lagoon toward the reef rim, the depth decreases sharply. In this transition zone, corals occur as circa metric patch reefs with great vitality. These patches are scattered in a large sandy area. Coral colonies are likely massive and submassive and few Acropora are visible.
The reef rim	Depth: 0 m.	The reef rim is the highest part of the intertidal portion of the reef, reaching a few centimeters above the upper level of coral growth. Here it is half-necrotic and is less than 10 m wide. Coralline algae cements the upper surface of the rim.
The outer slope (stations GW6 and GW7)	From 0 to 15 m, turbidity is not important, and coral diversity is the highest observed at Gaya West.	The outer slope is very steep and displays luxuriant hard corals, dominated by large heads of non-Acropora corals.
The sandy plain	Depth: −15 m.; Turbidity is very important.	At −15 m depth appears a plain characterized by slightly muddy fine sediment.

(b)  

Gaya East	Depth, turbidity, and currents	Description of the general morphology
The back reef (GE1 station)	This part of the reef is made of sand. The currents may be high during tides.	No hard coral is visible. Some scarce starfish occurs there.
The reef flat (GE2 to GE5 stations)	Depth: −4 to −2 m.; The water is not turbid. Because of the location behind a corridor occurring between the two islands, Pulau Bodgaya and Pulau Boheydulang, the currents may be violent during tides.	The reef flat is characterized by monospecific, circa 10 m in diameter, stands of branching Acropora, foliaceous Montipora, cf florida, or Pavona cactus. These large stands alternate with more diversified and smaller patches of branching, submassive, and massive non-Acropora (Pocillopora, Stylophora, Seriatopora, Psammocora, Favia, Favites, etc.).
The reef rim	Depth increases slowly.	There is no reef rim visible.
The inner slope (GE6 and GE7 stations)	From −2 to −15 m. First the slope gently goes down from −2 to −7 m for 50 meters and then becomes steeper from −7 to −17 m.	The two stations GE6 and GE7 are located in the steep area (−10 and −15 m).
The sandy plain	Depth: −17 m; Turbidity is not important.	At −17 m appears a plain made of fine sediment.

(c)  

Mantabuan	Depth, turbidity, and currents	Description of the general morphology
The mesh reef into the lagoon (M1 to M4 stations)	Depth: −1 to −5 m; The water is not turbid.	Into the lagoon, corals form a mesh reef. But the strips, 4 m high and 3 m wide, are less developed than in the Gaya West lagoon. The coral community is diverse, and Acropora is abundant. The upper parts of the strips are subtidal.
The transition from the lagoon to the reef rim	Depth: −2 m, high speed currents.	Toward the reef rim, the depth decreases, and an area made of very fine sand occurs with small coral patches of great vitality. Corals occurring there are likely massive and submassive, but Acropora is much more abundant than in the similar zone of Gaya West.
The reef rim	Depth: 0 m.	The reef rim appears as a subtidal area.
The outer slope (M5 to M7 stations)	Depth: from −2 to −15 m.; Low turbidity and high current speed.	First the slope gently goes down from −2 to −7 m (M5 station) and then becomes steep from −7 to −15 m (M6 and M7 stations). The diversity in corals is less important than in Gaya West outer slope.
The sandy plain	Depth: −15 m.; Low turbidity.	At −15 m appears a plain made of fine sediment.