The Sg. Pulai mangrove habitat supports 24 genuine mangrove plant species and 21 associate species, representing 84% of Malaysia‘s mangrove species, 79% of Malaysia‘s exclusive mangrove species and 37% of the world‘s true mangrove species.
The Sg. Pulai Mangroves can be broadly categorized into four vegetation types:
• Avicennia forests – pioneer species dominating seaward areas near the estuary of Sg. Pulai. Species include Avicennia alba (Api-api putih) and A. marina (Api-api jambu) with scattered trees of A. officianalis and Sonneratia alba (Perepat).
• Rhizophora-Bruguiera forests – occupy large areas within the Sg. Pulai forest reserve. Species include Rhizophora apiculata (Bakau minyak), Rhizophora mucronata, Bruguiera cylindrica (Berus), B. parviflora and Ceriops tagal (Tengar). A rare species, Avicennia lanata (Api-api bulu), is found along the south coast bordering the Straits of Johor and is endemic to Malaysia with a restricted distribution.
• Luminitzera-Scyphiphora forests – occur landward of the Rhizophora-Bruguiera forests. It represents a transition to the dryland mangroves of the hinterland and is inundated only by high spring tides. Species include Lumnitzera littorea and Scyphiphora hydrophyllacea (Cingam), and an abundance of ferns such as Acrostichum aureum and A.speciosum (Paku Piai). The freshwater banks riverbanks are dominated by the palm Nypa fruticans (Nipah).
• Dryland mangroves – occurs at the landward boundary of the Sungai Pulai Forest Reserve. The mangrove species here give way to other swamp and backsore species including Hibiscus tiliaceus (Bebaru), Cerbera odollam (Pong-pong), Podocarpus polystachyus (Podo laut), Intsia bijuga (Merbau ipil), Planchonella obovata (Menasi), Trema corymbosa, Calamus erinaceus (Rotan bakau) and Oncosperma tigillarium (Nibong).
There are distinct vegetation zones in the mangrove vegetation community with differences in the vegetation composition in relation to distance upstream from the river mouth and in relation to distance from the rivers and creeks. As the distance from the sea increases, the mangroves become more diverse with a highly mixed community in the back mangal. In areas where forestry production is active, the Rhizophora spp. (mostly R. mucronata) dominated the river banks. Moving further inland, they are replaced by a mixture of Bruguiera spp.,