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Ganl. Bull. Singapore 70 (Suppl. 1) 2018 
In Southeast Asia, freshwater swamp forest is a rather understudied forest type, 
mainly owing to its inaccessibility and the occurrence of insect-borne diseases within 
them (Yamada, 1997). Other wetland habitats, such as mangrove and peat swamp forests, 
have tended to receive more attention (Dudgeon, 2000). Nevertheless, the freshwater 
swamp forests of Peninsular Malaysia were surveyed relatively comprehensively by 
Corner (1978), and additional work has been done in Cambodia (Theilade et al., 2011) 
and Singapore (Ng & Lim, 1992; Turner et al., 1996; Lim et al., 2011). 
Freshwater swamp forest can be broadly characterised as forest that is subjected 
to flooding with relatively mineral-rich fresh water (Whitmore, 1984). As tropical 
freshwater swamp forest is a formation of tropical rainforest, several environmental 
conditions are common between freshwater swamp forests and other tropical rainforest 
formations (e.g. high humidity levels and solar irradiance; see Richards, 1996). 
However, beyond these commonalities, conditions found within freshwater swamp 
forests and other tropical rain forest formations can differ greatly. Flooding in inland, 
freshwater swamp forests is usually semi-permanent, irregular, or seasonal. Water 
depth also varies tremendously, ranging from a few centimetres to several metres. 
These physical factors, acting individually or synergistically, impact the ecology of 
freshwater swamp forests. Indeed, previous work by de Padua Teixeira et al. (2011) 
concluded that drainage patterns were the most prominent factor in the spatial 
organisation of plants in the swamp forests of Brazil. Despite the variable nature 
of freshwater swamp forests, sufficient water is always present during the growing 
season, which ensures that organisms adapted to living in water or waterlogged soils 
flourish (Junk et al., 2011). 
Freshwater swamp forests have several sources of water, including rain, rivers, 
and groundwater, whereas peat swamp forests obtain their water solely from rain 
(Richards, 1996; Goltenboth et al., 2006). The colour of the water in the freshwater 
swamp forest is often an indication of the levels of plant matter present in the water 
and soil. 
Management of freshwater swamp forests 
Freshwater swamp forest soils are relatively nutrient-rich, unlike ombrotrophic swamp 
forests, which receive nutrients solely via rain (Yule & Gomez, 2009). In freshwater 
swamp forests, nutrients and alluvial soils are subsequently deposited within the forest 
via rain and water table fluctuations (Whitmore, 1984; Richards, 1996; Whitten et al., 
2000; Goltenboth et al., 2006). The nutrient-rich soils in freshwater swamp forests 
have resulted in over-exploitation for agriculture, such as wetland rice cultivation 
(Richards, 1996; Whitten et al., 2000; Corlett, 2009) and oil palm plantations (Yule & 
Gomez, 2009). Indeed, Chokkalingam et al. (2007) reported that in southern Sumatra, 
fire of varying intensities was utilized to clear the swamp forest for agricultural 
purposes. The widespread and repeated fires there transformed a diverse and complex 
habitat into a habitat consisting of uniform stands of fire-resistant Melaleuca L. species 
thickets. Additionally, mismanagement of these ecosystems via extensive logging and 
