wetlands
a publication of Sungei Buloh Nature Park

Vol 8 No 2
Aug 2001


survivors of time: the horseshoe crab

insect study
tips on insect watching

zonation:
the landward mangrove fringe

landmark invasion
a walk in the past

fat worries of common
redshanks


Allan Teo
long-lasting companion
of the park

young naturalists
of the park

a nature journal
javan munia
 
zonation
& the landward mangrove fringe
ali ibrahim
conservation officer

highlights some interesting back-mangrove trees found in Sungei Buloh Nature Park

Generally, the seaward edge of the mangrove is dominated by pioneer species of Avicennia and Sonneratia.

On the bank of river estuaries, Rhizophora replaces their position. Behind this is a zone of mixed mangrove forest species of Rhizophora, Sonneratia, Bruguiera, Ceriops, Kandelia, Xylocarpus, Lumnitzera and Excoecaria.

But along rivers or in estuaries, groves of Nipah palms are usually found.

Moving towards the landward side of the mangrove forest, at the upper limit of salt-water penetration, where soil is of firm clay, various tree species represented here can adapt and grow within their respective range of tolerance to the influence of salt or brackish water. This is also the zone flooded by exceptional high water spring tides.

their presence ...
Mangroves that are badly disturbed or found on narrow coasts do not show well defined series of zones paralleling the coast. The phenomenon of zonation is still not fully understood. Factors controlling zonation lie in the response of tree species to salinity, tidal influence and soil conditions. The morphology, buoyancy and mode of establishment of propagules and its competition among the species are other possible factors affecting zonation.

The landward mangrove fringe communities share and compete for the same pollinators with the true mangrove communities as well as share the same predators and parasites. In the latter instance, they perhaps benefit the mangroves by playing as alternative hosts. Their presence also exemplifies the adaptive and evolutionary transition of land plants and may give valuable clues as to how mangroves were derived.
Examples of some of the interesting trees found in Sungei Buloh Nature Park back-mangrove community ...

Jati laut Podocarpus polystachyus is the only gymnosperm found in the swamp. Its long narrow leaf blade has an interesting light green flush when juvenile.

Putat ayam Barringtonia racemosa
has leaves obovate-lanceolate with leaf margin toothed and flowers on pendulous spikes.

Dungun Heritiera littoratis has leaves with silvery-white undersurface and keeled, boat-shaped, brown fruits.

Tui Dolichandrone spathacea is an endangered species, with pinnate leaves, very long tubular white flowers and long seed pods containing corky, winged seeds.

Portia tree Thespesia populnea has hibiscus-like yellow flowers which turn purple and fruits that are water-borne.

Pong pong tree Cerbeia odollam may remind you of a frangipani tree with white, yellow-eyed flowers and green turning red, apple-like fruits.

Katong laut Cynometra ramiflora has one to two pairs of leaflets and wrinkled and knobbed fruits.

Ipil Intsia bijuga is a tall tree with spreading crown and flat oblong seed pods.

Barat-barat Cassine viburnifolia is a small tree with inconspicuous greenish white flowers and small pendant-like fruits.

Sea Hibiscus Hibiscus tiliaceus is a somewhat untidy-looking tree with heart-shaped leaves and bright yellow flowers that turn maroon before falling.
   
© Sungei Buloh Nature Park