Conservation recommendations for Nee Soon 
211 
fauna. The study shows that rentention ponds with a fixed depth of 1 m could effectively 
reduce the flooding areas by about 90%. 
Summary conclusions and recommendations 
Management objectives for the Nee Soon freshwater swamp forest are driven by 
the need to conserve freshwater swamp forest habitat along with the fauna and flora 
supported by this (now) rare habitat in Singapore. The conservation value of the forest 
is relatively high since it is the last remaining freshwater swamp forest in Singapore 
and a high proportion of fauna found in the Nee Soon freshwater swamp forest are 
not found elsewhere in Singapore (e.g. Ng & Tim 1992, 1997; Yeo & Tim 2011). 
This study has vastly expanded our understanding of the history and current status of 
the Nee Soon freshwater swamp forest. Pressures on the ecology of the forest extend 
beyond those identified at the onset of this project, namely susceptibility to flood and 
drought, to encompass reservoir effects as well as potential impacts of erosion, land- 
use change and water quality. Biological baselines have been extensively updated, 
with rediscoveries of plant taxa previously thought to be locally extinct in Singapore, 
and discoveries of potentially new taxa. The research has also yielded new records of 
both flora and aquatic fauna. Extensive barcoding and imaging work has provided the 
tools for more rapid identification of taxa to a higher taxonomic resolution. Habitats 
closer to Nee Soon freshwater swamp forest edges, particularly in the vicinity of the 
spillway, comprised greater proportions of introduced species and macroinvertebrates 
associated with a different environment. Overall, faunal surveys indicate a healthy 
and diverse fish and aquatic macroinvertebrate communities in Nee Soon freshwater 
swamp forest. Hydrological influences were found to be substantial and potentially 
limiting community composition. Soil and water chemistry were also found to have 
significant effects. These results aid in identifying bottlenecks and thresholds for the 
maintenance of key aspects of Nee Soon freshwater swamp forest biodiversity. 
This paper has therefore presented a number of potential management solutions 
for the conservation and management of the swamp forest, some of which can be 
evaluated in the context of eco-hydrological modelling and others which warrant further 
investigation and consideration. For hydrological-engineering management options, 
the potential implications of modelled scenarios for in-stream faunal communities 
are presented. Proposed solutions are then discussed in the context of management 
objectives, cost-benefit and feasibility. 
The adoption of potential management solutions should reflect stakeholder 
priorities and management objectives and the relative importance of effects on the 
hydro-ecology of the system carefully balanced. Implementation of management 
efforts must consider ecological, hydrological and sedimentary processes. For 
example, management to restore hydrological integrity should be evaluated alongside 
ecological impacts. Protection and management of the Nee Soon freshwater swamp 
forest should aim to maximise carbon sequestration potential and functionality on the 
system as far as possible. 
