Grain-size distribution of sediment in the vicinity of Setiu Lagoon-estuary system

The sediments in the Setiu Lagoon-estuary system on the east coast of Malaysia consist mostly of coarse to very fine panicles. The major portions of the sediment are negatively skewed. The estuary area is under the influence of transportative and erosive forces. The lack of silt and clay in the estuary is attributable to less depositional factor under the influence of stronger current than in the lagoon area. The beach sediment ranges from coarse to fine sand. Generally, the mean grain-size decreases towards the north-west sector. The skewness value of the beach sand area is mostly negative, indicating that the study area is under the influence of rather strong wave and current action

Beach Erosion Variabiltiy during a Northeast Monsoon: The Kuala Setiu Coastline, Terengganu, Malaysia

It is widely accepted that beach erosion occuning along the coastline of the east coast states of Peninsular Malaysia is caused solely by the large waves of the northeast monsoon seasons. However, this study, which monitored 9 beach profile stations before and after a NE monsoon along a 25-km stretch of the Kuala Setiu coastline showed that only 2 of the 9 stations -located on both sides of the Setiu estuary river mouth - were eroded. The others showed accretion or negligible changes. Thus the assumption that the monsoon waves are the sole cause of beach erosion cannot be applied to all eroding coastlines. For some coastlines, theassumption may be only partly true. Wave refraction analyses show that, beside the large monsoon waves, the offshore bottom bathymetry and island shelters act as si~ specific factors either to help focus or disperse the energy of the monsoon waves to cause localized erosion or accretion. It is thus imperative that the modifYing effect of bottom topography and island shelters on monsoonal waves be considered if proper beach management policies and erosion mitigation measures are to be effective

Mangrove mapping using Landsat imagery and aerial photographs: Kemaman District, Terengganu, Malaysia

Classification and distribution of mangrove vegetation are vital information for the proper development of a mangrove management plan. In this study, classification for the mangroves of the district of Kemaman were done using both 1 : 5000 aerial photographs and Landsat TM imageries. The coverage by aerial photographs is limited to the coastal and estuarine areas only. Thus, for areas further upstream of the aerial photo coverage, Landsat TM imageries were used. Analysis of aerial photographs and remote sensing images revealed that the mangroves of Kemaman could be classified into 14 different classes of vegetation. All the 14 classes were identified from areas covered by the aerial photographs. For areas covered by the Landsat images only 7 classes of vegetation were identified. The accuracy for aerial photograph and Landsat images are 91.2% and 87.8%, respectively. It can be concluded that although both techniques are useful in determining the mangrove vegetation classes, the large 1 : 5000 aerial photographs are more accurate and provided more detailed information comparatively

Short-term Impact of Beach Fest on the Topography, Vegetation Coverage and Sediment Distribution of the Mengabang Telipot Beach, Terengganu

Grid measurements of beach vegetation, beach profile surveys and sediment analyses were done before and after the beach fest in order to assess the impact of the festivities on a stretch of the Mengabang Telipot beach. Although the beach fest was held for only seven days, its impact on the beach was found to be damaging. Beach vegetation was completely destroyed, while the backshore and the front portion of the upper beach were eroded. Sediments on both the backshore and upper beach decreased in. mean size and became poorly sorted. The foreshore area, which was influenced by tides, was not affected by the beach festivities

ATTENUATION OF WAVES FROM BOAT WAKES IN MIXED MANGROVE FOREST OF RHIZOPHORA AND BRUGUIERA SPECIES IN MATANG, PERAK

In Malaysia, there are several small rivers and estuaries which are frequented by fishing boats. The wave action due to the movement of boats impact the coastal morphology of the area. In this paper, we have studied the wave reduction in mixed mangrove forest of Rhizosphere and Bruguiera species based on field observations of waves from boat wakes in Sg. Sangga Kecil of Matang forest reserve, west coast of Peninsular Malaysia. The unique physical characteristics of Bruguiera sp. and Rhizophora sp. such as the intricate knee root and numerous pneumatophores, respectively, impact the wave amplitudes in the mangrove forest. The reduction of wave amplitudes in a 15 m long transect of mixed mangrove forest at a given study site has been analysed in the present study. It is found that the wave reduction for each 5-m distance from the vegetation edge ranged from 47.4% to 9.6%. However, on a cumulative basis the wave reduction inside the mixed mangrove forest ranged between 47.4% to 72.8%, with an average of 63%. As far as the vertical trend is concerned the wave reduction in (0-10cm) level was 88.7% while in (10-20cm) level it was found to be 61.2%

Penilaian Indek Kerentanan Sosio-Ekonomi Terhadap Kenaikan Paras Laut Sepanjang Pesisir Pantai Timur Semenanjung Malaysia

Sejak kebelakangan ini kesan kenaikan paras air laut sering dibincangkan di seluruh dunia khasnya negara-negara maritim, negara yang berada di bawah paras laut dan negara kepulauan. Kenaikan paras air laut ini mengakibatkan kemusnahan kawasan di pesisir pantai terutamanya dari segi sosio-ekonomi. Kenaikan paras air laut juga menyumbang kepada  hakisan pantai, banjir dan kemasukan air masin ke kawasan daratan. Ini mengakibatkan penduduk pesisir pantai kehilangan punca pencarian akibat dari kemusnahan ekosistem dan kerosakan harta benda. Salah satu kedah mengukur tahap kerentanan disebabkan oleh kenaikan aras laut ialah  dengan  menggunakan jangkaan kenaikan paras laut tempatan tahunan dan pelbagai pembolehubah sosio-ekonomi. Tahap kerentanan dapat memberi maklumat untuk perancangan adaptasi bagi kawasan yang dinilai. Oleh itu, objektif kajian ini ialah mengenalpasti tahap indek kemusnahan dan Penilaian Indek Kerentanan sosio-ekonomi penduduk pesisir pantai. Kajian di jalankan di empat buah negeri sepanjang pantai timur Semenanjung Malaysia iaitu Kelantan, Terengganu, Pahang dan Johor merangkumi 15 daerah pesisir pantai bermula dari Tumpat, Kelantan sehingga ke Kota Tinggi, Johor. Tiga parameter sosio-ekonomi diambil kira iaitu kualiti kehidupan, nilai ekonomi dan infrastruktur. Ketiga-tiga parameter ini dinilai dengan menggunakan indek kemusnahan sosial dan dipetakan menggunakan perisian ArcGIS 2010. Hasil kajian mendapati Kuantan merupakan daerah yang mempunyai indek kemusnahan paling tinggi bagi keseluruhan parameter yang diukur. Langka berjaga-jaga dan  pencegahan dari kerajaan dan bukan kerajaan perlu diambilkira  untuk mengurangkan kerentanan sosio-ekonomi akaibat dari kesan  kenaikan paras laut.  &nbsp

An Analysis of the Early Regeneration of Mangrove Forests using Landsat Time Series in the Matang Mangrove Forest Reserve, Peninsular Malaysia

Time series of satellite sensor data have been used to quantify mangrove cover changes at regional and global levels. Although mangrove forests have been monitored using remote sensing techniques, the use of time series to quantify the regeneration of these forests still remains limited. In this study, we focus on the Matang Mangrove Forest Reserve (MMFR) located in Peninsular Malaysia, which has been under silvicultural management since 1902 and provided the opportunity to investigate the use of Landsat annual time series (1988-2015) for (i) detecting clear-felling events that take place in the reserve as part of the local management, and (ii) tracing back and quantifying the early regeneration of mangrove forest patches after clear-felling. Clear-felling events were detected for each year using the Normalized Difference Moisture Index (NDMI) derived from single date (cloud-free) or multi-date composites of Landsat sensor data. From this series, we found that the average period for the NDMI to recover to values observed prior to the clear-felling event between 1988 and 2015 was 5.9 ± 2.7 years. The maps created in this study can be used to guide the replantation strategies, the clear-felling planning, and the management and monitoring activities of the MMFR.SCOPUS: ar.jinfo:eu-repo/semantics/publishe