Standing guard at the gates of the rivers of Singapore, the mangroves spread their roots, welcome the tides, and protect the land against the floods of the sea. Filled with the melodies of cicadas and interrupted by the songs of birds, the mangrove ecosystem, with its mix of riverine freshwater and salty seawater creates the brackish conditions that are home to countless species of plants, insects, fish, reptiles, and birds. From the two-meter-long saltwater crocodiles to the magnificent blue kingfishers, to the tiny crabs, the mangroves function as a treasure chest of biodiversity. The intertwingled short prop-roots of the Oriental Mangrove, Bruguiera gymnorhiza, hugging the sandy ground reminded me of a squiggly ancient writing language while the long stilt-roots of the Red Mangrove, Rhizophora apiculata, reminded me something you can find in a modern art museum.

Figure 1. The intricate roots of the Oriental Mangrove, Bruguiera gymnorhiza at low tide, with visible neighboring pencil roots. (photo credit: Joseph Baha Taher).

Visiting the mangrove ecosystem of Sungai Buloh Wetland Reserve with my NUS GE3255 Aquatic, Riparian, and Coastal Ecosystems class, I was captivated by the uniqueness of this environment. As you walk from the terrestrial rainforest with its big trees, dense leafy understory and dry soils, and into the mangrove you are filled with a sense of fascination. As the canopy opens up, the sun exposes an intricate and amazing root system. The type of roots changes depending on where they are in the mangrove. From the buttress roots at the landward zone that stabilize and anchor the trees to the ground, to the pencil roots in the seaward zone that enables the trees to respire despite the waterlogged soils. The roots of these trees have adapted to the unique environment of the mangrove. With a great diversity of roots, the trees in the mangrove forest survive where none other can.

 

Figure 2. The prominent roots of a true mangrove of the genus Rhizophera, as seen in low tide in Sungei Buloh Wetland Reserve (photo credit: Joseph Baha Taher).

Looking at the different roots and imagining the life and security that these roots provide I understand why mangroves are important to preserve. As with the tidal mudflats and marshes that I am familiar with from my native Denmark, I can see that the way to restore these ecosystems is to give them space and time. The tides and rivers will together create the environment for mangrove growth if we clear the space for these forests to expand and grow again, maybe with a helping hand in planting a tree or two. The roots of the mangrove will spread and expand the forests, creating the sea walls we need for flood protection and the homes the animals and plants need for thriving.

Figure 3. A saltwater crocodile Crocodylus porosus appearing in waters of Sungei Buloh, exemplifying the animals inhabiting these brackish waters (photo credit: Joseph Baha Taher).