Please use this identifier to cite or link to this item: http://scholarbank.nus.edu.sg/handle/10635/53668
Title: Tracing Sources and Spatial Distribution of Seagrass Sediments, Yao Yai Island, Thailand
Authors: QUAK SONG YUN, MICHELLE
Keywords: catchment-coast connectivity, sediment tracing, acidification, landscape connectivity; SIAR mixing model.
Issue Date: 24-Jan-2014
Source: QUAK SONG YUN, MICHELLE (2014-01-24). Tracing Sources and Spatial Distribution of Seagrass Sediments, Yao Yai Island, Thailand. ScholarBank@NUS Repository.
Abstract: Coastal vegetated ecosystems are recognised for their long-term carbon sequestration and high capacity carbon storage that can mitigate associated impacts of global climate change. However, due to the catchment-coast connectivity, coastal ecosystems are often at the receiving end of terrestrial-derived pollution. As sedimentation is a major threat to coastal ecosystems, tracing may allow managers to identify point sources which can be targeted for mitigation strategies. The significance of considering ecosystem connectivity is demonstrated by using d13C and d15N isotope tracers and the SIAR mixing model to map the composition and distribution of deposited sediment in a seagrass bay of Yao Yai Island, Thailand. Through mixing polygon diagrams, weak acidification (acid fuming) on organic matter adsorbed on sediments, to remove inorganic carbon, was found to provide the most suitable source signatures and seagrass sediment signatures for the sediment mixing model. Kriging interpolation showed that 50-60% of sediments in close proximity to river mouths were terrestrial- and mangrove-derived. Rivers enhance connectivity from catchments to the coastal bay, implying that mangroves may not be effective buffers for seagrass ecosystems when major flow pathways directly link terrestrial and coastal areas. Landscape composition and configuration of the catchment was identified as an important factor contributing to the extension of the channel network which improves hydrologic connectivity of the system and delivery of sediments to the coast. Thus, a wider catchment-coastal system perspective and approach must be adopted when managing sedimentation problems in coastal ecosystems. Mitigation measures should not focus on adaptation response at the coast, but concentrate on selecting suitable targeted solutions for land use management which addresses erosion and hydrological/landscape connectivity.
URI: http://scholarbank.nus.edu.sg/handle/10635/53668
Appears in Collections:Master's Theses (Open)

Show full item record
Files in This Item:
File Description SizeFormatAccess SettingsVersion 
QuakSYM.pdf2.3 MBAdobe PDF

OPEN

NoneView/Download

Page view(s)

301
checked on Dec 11, 2017

Download(s)

141
checked on Dec 11, 2017

Google ScholarTM

Check


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.