Integrated research, conservation and management of Nee Soon freshwater swamp
            forest, Singapore: hydrology and biodiversity

ABSTRACT. This paper presents initial findings from research on the hydro-geomorphic status of Nee Soon freshwater swamp forest catchment in Singapore. The hydrological system of Nee Soon contains a swamp that is best described as an organic-rich wetland, with organic matter content as high as 40% near the surface (too low to be classified as peat). Total longterm denudation rate in the catchment is an estimated 23.4 ± 2.08 Mg km -2 yr -1 , with physical erosion (5.6 ± 0.5 Mg km -2 yr -1 ) and chemical weathering (17.8 ± 1.58 Mg km -2 yr -1 ) accounting for 24% and 76% of the totals, respectively. Age dating of a 1.95-m sediment core from the lower swamp indicates several distinct periods of variable sediment deposition (0.04 to 0.009 cm y -1 ) since 15,000 BCE, across a variety of climate regimes. A missing layer, representing more than a 7000 year period, verifies substantial channel erosion in the swamp occurring since 1950. Accelerated erosion associated with forest conversion to agriculture in the upper catchment could not be verified through examination of sediment cores. High concentrations of several heavy metals (e.g. As, Cr, Mn, Ni, Sr, V) in the lower catchment, compared with the upper catchment, appear to be natural (e.g. related to differences in the underlying bedrock), rather than contamination. The very high concentrations of lead, copper, and zinc associated with firing activities in the military range in the lower catchment are spatially isolated (e.g. shooting berms), and currently not posing a threat to the swamp environment. Other hydrogeomorphic degradation processes/activities now include disruption to hillslope soils and streams by trampling and mountain biking, back-flow of reservoir release water into the lower swamp area, and atmospheric deposition of contaminants.

Section: Introductionmentioning

confidence: 99%

The hydro-geomorphic status of Nee Soon freshwater swamp forest catchment of Singapore

Nguyen¹,

Wasson²,

Ziegler³

2018

“…Therefore, it is important to maintain Nee Soon freshwater swamp forest in its current state, as well as ensure that it is not affected adversely by development. These are amongst the reasons for conducting a long-term research project to intensify knowledge of the freshwater swamp forest system (Davison et al, 2018).…”

Section: Discussionmentioning

confidence: 99%

The biological, ecological and conservation significance of freshwater swamp forest in Singapore

Clews¹,

Corlett²,

Ho³

et al. 2018

ABSTRACT. The Nee Soon stream drainage in the Central Catchment Nature Reserve is virtually the last remaining fragment of primary freshwater swamp forest in Singapore. The forest type has been poorly studied in the Southeast Asia. The hydrology, water quality, as well as aquatic flora and fauna all have great theoretical and practical significance. The ecology and management of the Nee Soon freshwater swamp forest are reviewed, with remarks on their national, regional and global contexts. This review sets the scene for a three-year integrated conservation and management study completed in 2016.

“…The project was carried out in two phases, from January 2011 to March 2012, and from February 2013 to August 2016. The detailed aims of each phase are listed by Davison et al (2018). Table 1 summarises the achievements of the project and these fully covered the listed aims.…”

Section: Project Aimsmentioning

confidence: 99%

“…The Nee Soon hydrology and biodiversity project was a response to the need for better understanding of the forest ecosystem and its dynamic processes, as a basis for management and monitoring (Davison et al, 2018). A detailed but still in many respects preliminary review of the results has been given in the accompanying papers in this same volume Chong et al, 2018;Clews et al, 2018;Ho et al, 2018;Kutty et al, 2018;Lim et al, 2018;Nguyen et al, 2018;Sun et al, 2018).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Conservation outputs and recommendations for Nee Soon freshwater swamp forest, Singapore

CAI¹,

Davison²,

Chan³

et al. 2018

Self Cite

ABSTRACT. The current paper acts as a summary to the "Nee Soon Swamp Forest biodiversity and hydrology baseline studies project", including results published previously and the results from papers of the current volume. Overall, flora and fauna surveys indicate healthy and diverse plant, fish and aquatic macroinvertebrate communities in Nee Soon freshwater swamp forest. There are some concerns over terrestrial and aquatic alien invasive species, loss of big emergent trees, small population sizes and viability of various native species, and the uncertain outcomes of changes in water quality and quantity. The findings inform management that Nee Soon freshwater swamp forest is especially vulnerable to changes in hydrology and there is much dependency on precipitation for its water budget. Projected climate change effects on precipitation and statistical analyses of biotic responses to hydrology clearly define drought as a major, perhaps the foremost, source of vulnerability to the ecosystem functioning of Nee Soon freshwater swamp forest. Potential management solutions are suggested to address five issues of concern for the forest: hydrological integrity, erosion and sedimentation, ecological integrity, the impact of the spillway, and impacts of construction and development.