3er Congreso Nacional de Investigación en Cambio Climático
Spit formation in the Baram River mouth, Eastern Malaysia (Sarawak), South China Sea: Effect of deforestation
R.
1
Nagarajan ,
V.C.
2†,
Shruti
M. P.
2
Jonathan ,
P. D.
3
Roy ,
G.
4
Muthusankar and
C.
5
Lakshumanan
1Department
of Applied Geology, School of Engineering and Science, Curtin University, CDT 250, Miri, 98009, Sarawak, Malaysia.
2Centro Interdisciplinario de Investigaciones y Estudios sobre Medio Ambiente y Desarrollo (CIIEMAD), Instituto Politécnico Nacional (IPN),Calle 30 de Junio de 1520, Barrio la Laguna Ticomán, Del. Gustavo A. Madero,
C.P.07340, México DF., México.
3Instituto de Geología, Universidad Nacional Autónoma de México (UNAM), Ciudad Universitaria C.P. 04510, Coyoacan, México DF., México.
4French Institute of Pondicherry, 11 St Louis Street, P.B. 33, Puducherry – 605 001, India.
5Centre for Remote Sensing, Bharathidasan University, Khajamalai Campus, Thiruchirappalli – 620 023, India.
†Corresponding author. Tel.: +52 5557296000 Ext: 52707, 52708; fax: +52 5557296000
†E-mail address: [email protected]
ABSTRACT
Spits are among the most dynamic features in the coastal zones. Their stability is very often the result of a fragile equilibrium between the availability of
sediments and the river and coastal hydrodynamics. The present study was carried out in a spit formed in front of the Baram River in eastern Malaysia
located in the South China Sea. The main objective was to identify the correlation between climatic events and anthropogenic activities in the upstream
side. The field observations and satellite image classification revealed that the region in front of the river has strengthened to a barrier island after the
initial formation and it extends to the south of the river mouth. It is inferred that there is a direct relationship with the human interferences in the
upstream side indicating heavy input of finer sediments during major flooding. The spit formation has a direct association with the major flooding and
2
precipitation in the region showing an increase in tidal flat (double in size from 2006 – 0.30 Km ) and mud flats (six fold increase from 2005 – 0.29
Km2) from 2005 to 2013. The classified satellite images infers that the spit formation has taken place after 2005 and it also has a direct relationship with
the sediment input from the Baram River.
INTRODUCTION
RESULTS AND DISSCUSSION
Spits are made up of sediments by suspended particles transported by waves and
currents. A barrier spit is the landform resulting from the deposition of sediments
in long ridges extending out from the coasts. Natural factors like breaching,
cyclonic events, storms as well as anthropogenic activities in the land region bring
about significant geomorphological adjustments over the spit formation in the
coastal region. The main theme of this research is to investigate spit development
of the Baram River delta using satellite images, through field investigations and to
know the changes and growth during
its formation .
RESEARCH AREA & ITS
FEATURES
SPIT FORMATION &
STABILIZATION PROCESS
TIMBER LOGS TRANSPORTED
DURING CYCLONIC EVENTS
ARTIFICIAL SEA WALL STUCTURES TO
PROTECT EROSION
SUMMARY
The formation of this barrier island and its development is aided mainly by the
human interference (like building dams) in the natural environment, where land use
changes often bring in huge supplies of finer sediments during major flooding
events in the upstream side. Moreover, the results also suggest that the
development is controlled by the sediment load, flood frequency, period of
maximum storminess and annual maximum sediment discharge of Baram River.
Figure1
Figure 2
Figure 3
The geomorphological changes and development (from 1991,
2005, 2009, 2010, 2013) of the barrier island and the spit
formation in the region in front of River Baram is observed in
Fig.1.(Nayak et al., 1991; Jayappa et al., 2006).The beach area
has increased gradually from 2005 to present day (Fig.2a). The
calculated coastal vegetation in the region indicates a gradual
increase from 27.35 to 27.82 Km2 (Fig. 2b). Gradual increase in
2
area is observed in mud flat from 0.06 to 0.30 Km and tidal
flats from 0.16 to 0.29 Km2 (Fig. 2c-d). However, the river
mouth has shown a steady decrease in size from 2.78 to 2.41
Km2 . Beach sand deposits in the barrier island and in the
beaches of the southern side of Baram River has increased
considerably (0.88 to 1.03 Km2) and it is approximately present
more than 3 km along the shoreline in the south of river mouth.
Average monthly rainfall graph in Fig.3. indicates a cyclicity of
higher rainfall every second year from 1983 to 1998 and after
2000 it shows a decreasing trend. The region normally is
strongly influenced by the tropical cyclones due to its proximity
to the West North Pacific and South China Sea. (Ariffin and
Moten 2009).
REFERENCES
Ariffin, M., Moten, S., 2009.Malaysian Meterological Dept (MMD) and Ministry of Science,
Technology and Innovation (MOSTI), 2/2009, 20p.
Jayappa, K.S., Mitra, D., and Mishra, A.K., 2006. Int. J. Remote Sen., 27, 3671–3682
Nayak, S., Bahuguna, A., Shaikh, M.G., Rao, R.S., 1991.Technical Note.
IRSUP/SAC/MCE/TN/32/91:63.