Assessment and demarcation of trail degradation in a nature reserve, using GIS: case of Bukit Timah Nature Reserve

Abstract

With a significant rise in popularity of nature areas, particularly in urban settings like Singapore, Nature Reserves are being increasingly opened for public recreational use. In the Bukit Timah Nature Reserve (BTNR), the only remnant primary rain forest reserve in Singapore, trail networks are being expanded to meet this growing public demand. The physical condition of the present trail networks was assessed by monitoring the changes in surface compaction, soil moisture, infiltration rates, soil organic matter content, root density, litter cover and rill development. These parameters were compared with similar data obtained from undisturbed forested slopes to analyse the degree of changes brought about by trail usage. Significant changes occurred in all measured parameters, indicating observable degradation of the trails, particularly on vulnerable slopes. These changes are due to the heavy and increased use of the forest by visitors. Penetration resistance and shear strength of the top surface layers of the trails are important indicators of trail degradation status and these have been plotted, using GIS, to demarcate trails under different levels of stress. This field monitoring provides a relevant local assessment of trail conditions. It has potential for use in decision-making in future planning and forest management under similar site conditions.

Quantifying Soil Erosion from Hiking Trail in a Protected Natural Area in the Spanish Pyrenees

“…Long-term recreational uses may lead to soil compaction, muddiness, erosion and/or trail widening (Deluca et al, 1998;Chatterjea, 2007;Özcan et al, 2013), which in turn may significantly impact hydrophysical variables such as macroporosity, porosity, void ratio and saturated hydraulic conductivity but also favour an increase of bulk density (Sutherland et al, 2001). Soil compaction due to recreational trampling will also facilitate overland flow erosion (Hanson et al, 2004;Li et al, 2005;Pelfini & Santilli, 2006;Torn et al, 2009;Ramos-Scharron et al, 2014).…”

Characterizing human–macaque interactions in Singapore

“…Although having a population of over 4,500,000 people in a total land area of 682.7km 2 , Singapore retains at least 20km 2 of forested area, including two national reserves surrounded entirely by urban development. A substantial and increasing number of people frequent these forested areas annually [Chatterjee, 2007]. In addition to the human population, there are approximately 1,470 long-tailed macaques ( Macaca fascicularis ) present in and around the forested zones [Sha, 2008].…”

Sustainability of an Urban Forest: Bukit Timah Nature Reserve, Singapore

“…However, with the increasing number of visitors, this does not seem to ameliorate the problem but further impact the forest by taking visitors more and more into the forest interiors. Research has also established that trails are not only heavily used, but also widened through overuse, thus degrading the immediate peripheries of the trails as well (Chatterjea, 2007). With mainly recreational use of the forest, as Sutherland et al (2001) suggest, it is important to examine the impact of recreational hiking on soil hydro-physical characteristics as well as to identify indicators of trail degradation so that the data can be used by land managers to assess the degree of stress imposed by recreational impacts.…”

“…Measured values of penetration resistance and shear strength, infiltration rate (Gardner and Chong, 1990) of the top surface soil can be analysed to show how increase in trail use leads to increased surface soil compaction and thus alters the original forest surface hydrological characteristics. Chatterjea (2007) gives details of the trail degradation and provides spatial information on hazardous trail segments which can be used by the forest management to target their repair works to affected sites as well as to plan future repairs, depending on requirements. Data regarding trail degradation along the well-used forest paths in BTNR are compared with the original undisturbed forest surfaces ( Table 2).…”