AN ASSESSMENT ON THE AN ASSESSMENT ON THE EFFECTS OF THE EFFECTS OF THE TSUNAMI ON THE TSUNAMI ON THE
MALAYSIAN CORAL REEFSMALAYSIAN CORAL REEFS
Zulfigar Yasin, Anisah Lee and Zulfigar Yasin, Anisah Lee and Aileen TanAileen Tan
Centre for Marine And Costal Centre for Marine And Costal StudiesStudies
Universiti Sains MalaysiaUniversiti Sains Malaysia
Location of North Location of North Malaysian coast affected by Malaysian coast affected by
the Tsunamithe Tsunami
Landsat Thematic Mapper image of the coastal region of North Peninsular Malaysia
HABITAT CLASSES
Permanent shallow marine waters (5 m depth contour)
Intertidal mudflats
Mangrove Reclaimed land
Coral reefs Rocky shore
Seagrass bed Sandy shore
Manmade island
LANGKAWI ISLANDS
PAYAR ISLANDS
SONGSONG ISLANDS
PENANG
ALOR SETAR
Kuala Kedah
Merbok
Kota Kuala Muda
Butterworth
Muka Head Marine Research Station USM
North
STRAITS OF MALACCA
Scale 1:80 000
Georgetown
Existing Coastal Habitats
LANGKAWI ISLANDS
PAYAR ISLANDS
SONGSONG ISLANDS
PENANG
ALOR SETAR
Kuala Kedah
Merbok
Kota Kuala Muda
Butterworth
MukaHead Marine Research Station USM
North
STRAITS OF MALACCA
Scale 1:80 000
Sg. Aceh
Sg. Muda
Sg. Merbok
Sg. Kedah
Sg. Udang
Pu. Kendi
Balik Pulau
Tk. Bahang
Bt. Feringghi
Pu. Singa BesarPu. Beras Basah
Pu. Segantang
Pu. Payar
Pantai Chenang
Pantai Kok
Tg. Malai
Areas of tsunami impact
Muka Head Marine Research StationMuka Head Marine Research Station
Universiti Sains MalaysiaUniversiti Sains Malaysia
Research on the Seas and Islands of Malaysia (ROSES) - Voyage Route 2004
LEGEND
SECTION 1
SECTION 3
Pre-tsunami image
Subset
Study Area
Masking
Pre-tsunami Coastal Area
Atmospheric correction
Pre-tsunami coastal area
Supervised Classification
Supervised Classification Pre-
tsunami Coastal Habitat MapArchival data
(ROSES etc)Accuracy
Assessment
High Accuracy (>75%)
Map Composition Output:
Pre-tsunami Coastal Habitat Classification Map
Reclassification
Low Accuracy (75%)
Post-tsunami image
Subset
Study Area
Masking
Post-tsunami coastal area
Atmospheric correction
Post-tsunami coastal area
Supervised Classification
Supervised Classification Post-
tsunami Coastal Habitat Map
Groundtruthing data
Accuracy Assessment
Low Accuracy ( 75%)
Map CompositionOutput:
Post-tsunami Coastal Habitat Classification Map
High Accuracy (>75%)
Final Output:
Coastal Habitats Affected by Tsunami
Change Detection Analysis
Image Pre-processing Phase
Image Processing Phase
New survey data
Coral reefs – offshore Coral reefs – offshore islandsislands
Offshore reefs islands Offshore reefs islands surveyedsurveyed
Evidence unlike that of Evidence unlike that of large storm damagelarge storm damage
Erosion on reef tops Erosion on reef tops especially the reef especially the reef edgeedge
Sediment resuspension Sediment resuspension and damage to fragile and damage to fragile coral skeletonscoral skeletons
Fringing reefsFringing reefs
Deeper water reefs Deeper water reefs less affectedless affected
Shallow and intertidal Shallow and intertidal reefs most affectedreefs most affected
Evidence of Evidence of secondary effects of secondary effects of tsunami already seentsunami already seen
Stress monitoring Stress monitoring underwayunderway
Sea grass beds and Sea grass beds and mudflatsmudflats
Mudflats and Mudflats and coastal sandy coastal sandy beaches show beaches show change in beach change in beach profileprofile
Changes in animal Changes in animal community profile community profile
Epifauna affected Epifauna affected Indication of Indication of
community changescommunity changes
Sea condition Sea condition three hoursthree hours after the tsunami event - after the tsunami event -
ebbing tideebbing tide
Sea condition - Sea condition - 8 minutes 8 minutes laterlater
Fish kill a day after the tsunami Fish kill a day after the tsunami eventevent
Remains of fishermen’s Remains of fishermen’s aquaculture cages in Penang - 3 aquaculture cages in Penang - 3 hours after the tsunami eventhours after the tsunami event
Largest change of generic reef Largest change of generic reef types between the SCS and the types between the SCS and the
Indian OceanIndian Ocean
Some salient pointsSome salient points Important not to Important not to generalisegeneralise impacts impacts Pre-tsunami dataPre-tsunami data and ecological behaviour critical and ecological behaviour critical
in assessmentin assessment ImmediateImmediate post tsunami monitoring important for post tsunami monitoring important for
effects not to be maskedeffects not to be masked Assessment must have a Assessment must have a predictive valuepredictive value and and
therefore detail scientific assessment importanttherefore detail scientific assessment important Devastation in Acheh reefs and Malaysian offshore Devastation in Acheh reefs and Malaysian offshore
islands mostly unknownislands mostly unknown Immediate need to set up post tsunami assessment Immediate need to set up post tsunami assessment
specifically for coral reefs in the impacted areas of specifically for coral reefs in the impacted areas of Malaysia, Thailand and IndonesiaMalaysia, Thailand and Indonesia