Andaman Sea Coast Of Thailand Research Articles

Application of three materials of fishing gear marking for crab and fish gillnets in small-scale fishery in the Andaman Sea coast of Thailand

Application of three materials of fishing gear marking for crab and fish gillnets in small-scale fishery in the Andaman Sea coast of Thailand

Population Genetic Structure of the Blue Swimming Crab (Portunus pelagicus) Along the Andaman Sea Coast of Thailand

The blue swimming crab (Portunus pelagicus) is a valuable commercial species. In Thailand, the consumption of the blue swimming crab is increasing. To construct an effective sustainable management plan, genetic information is required. Knowledge of natural stock genetic information can help policymakers design fishing and conservation management policies to maintain genetic diversity. In our study, we examined the genetic structure of the blue swimming crab population on the Andaman Sea coast of Thailand. Partial sequences of the mitochondrial DNA control region (mtDNA CR) with a size of 369-371 base pairs were studied in 150 individuals collected from five sampling sites along Thailand's Andaman Sea coast. Seventy-one haplotypes were characterized by 127 polymorphic sites, indicating high haplotype diversity but low nucleotide diversity across five localities. The multiple tests of population genetic analysis showed a lack of genetic structure. The absence of genetic structure was possibly caused by a high level of gene flow due to the larval blue swimming crab's high dispersal ability. Demographic history findings indicate that the blue swimming crab population has expanded. The findings of our study can be used to guide the management of the blue swimming crab in this region of the Andaman Sea to conserve genetic diversity.

Cetaceans and mass strandings in Thai waters

A total of 25 species of cetaceans have been recorded in Thai waters from stranding and sighting records. A summary of these, together with details of five mass strandings on the Andaman Sea coast of Thailand, are reported here. The first mass stranding, of nine spinner dolphins (Stenella longirostris) was at Talibong Island, Trang Province, in January 1999; six carcasses were examined and three were lost. The second record comprised five spotted dolphins (Stenella attenuata) stranded at Ban Ko Kho Khao, Phang-nga, in February 1999; two dolphins were released alive. The third stranding was of eight spotted dolphins at Mai Phai Island, Phang-nga, in March 2006; five animals died and three were released alive. The fourth mass stranding was of 30 false killer whales (Pseudorca crassidens) at Racha Yai Island, Phuket, in June 2008; 29 animals were released while one drowned. The fifth record consisted of three rough-toothed dolphins (Steno bredanensis) stranded at Nam Bor Bay, Phuket, in July 2008; all three were returned to the open sea. It was difficult to determine the causes of death of the stranded dolphins. However, it was possible that the first two mass strandings were caused by disease. Some strandings were possibly influenced by the landscape of the stranding locations (narrow bay in one case, wide gently sloping beach in another).

Multi-proxy approach to identify the origin of high energy coastal deposits from Laem Son National Park, Andaman Sea of Thailand

Understanding the frequency of high energy storm and tsunami events is crucial for apprehending the vulnerability of coastal communities. Identifying and dating sedimentary evidence deposited by such high energy events can assist in the planning and installation of suitable protection measurements. The Andaman Sea coast of Thailand is particularly vulnerable to such events as illustrated by the 2004 Indian Ocean Tsunami. Here, three shore-perpendicular transects and ten sediment cores along a beach ridge in the northern part of Lam Son National Park, Ranong Province, Andaman Sea coast are investigated with respect to high energy deposits. A multi-proxy analysis was conducted including stratigraphical correlations between cores, detailed description of physical characteristics, sedimentary structure, grain size, organic matter and carbonate content as well as identification of the remains of marine organisms. Optically stimulated luminescence (OSL) dating was applied for determining the age of the sediments on this beach ridge plain. The stratigraphy and sediment characteristics, in particular composition, of the sands in the study area clearly allow us to distinguish between high energy deposits and normal beach sediments. Two high energy deposits were identified and attributed to result from the 2004 Indian Ocean Tsunami as well as a past storm, which, based on OSL dating occurred more than 340 ± 20 years ago.

Application of the Ecopath model for evaluation of ecological structure and function for fisheries management: A case study from fisheries in coastal Andaman Sea, Thailand

The Andaman Coastal Sea provides a rich resource of seafood as well as a major contribution to the socio-economy of many local communities in Thailand. The aim of this study is to model food web structure and estimate energy flow through trophic levels using the Ecopath tool. Data have been collected on fish length, weight and diet composition from three provinces, Krabi, Phuket and Phangnga along the Andaman Sea coast of Thailand. Data from commercial as well as artisanal fishing ports were entered into the model. The model computed data for trophic level, food web structure, and ecological function of functional groups. The results indicate that the coastal ecosystem of the Andaman Sea is composed of five aggregated trophic levels of 46 functional groups, ranking from 1.0 to 4.227. The total system throughput is 9162.513 t km−2 y−1 and internal consumption, respiration, flow into detritus, and export out of the system accounts for 28.83%, 16.06%, 28.34%, and 26.77%, respectively. The Mixed Tropic Impact (MTI) shows detritus and low trophic level groups make a significant contribution to the diet of groups at higher trophic levels. Planktivorous fishes are important components of food web structure. The total system throughput analysis indicates that the ecosystem is in a relatively immature state. Pedigree analysis showed that the model has high reliability. The application of the model for fisheries management is discussed. In particular, the use of the model for local Fisheries Improvement Projects is recommended.

Wave Energy Potential and Simulation on the Andaman Sea Coast of Thailand

Ocean wave energy is an interesting renewable energy because it will never run out and can be available all the time. If the wave energy is to be used, then the feasibility study of localized wave potential has to be studied. This goal is to study the potential of waves in the Andaman Sea. The Simulating WAves Nearshore (SWAN) model was used to calculate the significant wave heights, which were validated with the measurement data of the Jason-2 satellite. The coastal area of Phuket and Phang Nga provinces are suitable locations for studying wave energy converters because they have high significant wave height. Moreover, this study used computational fluid dynamics (CFD) for the simulation of wave behavior in accordance with wave parameters from the SWAN model. The wave height simulated from CFD was validated with linear wave theory. The results found that it was in good agreement with linear wave theory. It can be applied for a simulation of the wave energy converter.

Coral Diversity at Losin Pinnacle, an Offshore Reef in the Gulf of Thailand: Toward a Future MPA

Severe coral bleaching events in the Gulf of Thailand and the Andaman Sea coast of Thailand had caused widespread coral mortality in 1998 and 2010. Consequently, the decrease in coral populations impacted the structure, health, and services of Thai coral reefs. However, most colonies in the offshore reef of Losin were still alive after the coral bleaching events. Therefore, this study was conducted by the Department of Marine and Coastal Resources in order to help to establish a proposal for a Marine Protected Area (MPA). Surveys on coral diversity were conducted to produce a checklist of reef building corals. Seventy-six coral species were found, with the most dominant species being Porites lutea and Acropora communities, such as A. intermedia, A. grandis, A. muricata, A. cytherea, and A. valenciennesi. This area is expected to be designated as a restricted MPA area, under the “Act on the Promotion of Marine and Coastal Resources Management B.E. 2558 (2015)”. The high diversity of hard corals discovered in this study assist in promoting the inclusion of Announcement of the Losin Marine and Coastal Resources Protected Areas following the Ministerial Regulation.

Cirolana phuketensis, a new species of marine isopod (Crustacea, Isopoda, Cirolanidae) from the Andaman Sea coast of Thailand.

Cirolana phuketensis sp. n. was collected from coral rubble from the Andaman sea coast of Thailand. C. phuketensis sp. n. is described and fully illustrated; C. phuketensis sp. n. can be recognized by the presence of transverse sutures on pereonites 2–4, pereonite 7 having three transverse sutures forming a nodulose ridge, antennula peduncle with articles 1 and 2 fully fused; pleotelson dorsal surface with 2 sub-median longitudinal carinae, each of which has one prominent tubercle, lateral margins weakly convex, and posterior margin narrow and rounded; 6 molariform robust setae pereopod 1 on inferior margin of merus and the penial openings are two low tubercles. A dichotomous key to species of Cirolana in Thailand is given.

Guidelines on Halal Tourism Management in the Andaman Sea Coast of Thailand

The purposes of the research were to:1) evaluate the potential of existing Halal tourist places and to rank them; 2) examine (current) Halal tourism management practices in the Andaman Sea coast of Thailand catering for travelers from Muslim countries and; 3) propose feasible guidelines on Halal tourism management in this area. The sample groups were government officers working in the tourism-related sections, administrators in the sub-district administrative organization offices in the provinces along the Andaman Sea coast, community leaders, tour guides, officers of the provincial offices of the Islamic Council in the Andaman Sea coast, Muslim tourists from Muslim countries and officers of the Central Islamic Council of Thailand. The research instruments included a questionnaire, observations and focus group discussions. The findings suggests that Halal tourism operators must provide prayer rooms for Muslim tourists as well as the direction signs to the mosque either in English or Arabic, separate restrooms for men and women. In addition, Halal restaurants should be provided in tourist attraction areas.

Life on a leaf: 3D-reconstruction and description of a new limapontiid sacoglossan (Gastropoda: Heterobranchia: ‘Opisthobranchia’) living on the seagrassHalophila ovalis

Sap-sucking sea slugs, Sacoglossa, are almost all suctorial herbivores feeding on siphonalean green algae. Ercolania is probably the most species-rich genus in the family Limapontiidae, containing at least 25 species, most of which feed on filamentous green algae of the order Cladophorales. Here we describe an ewErcolania species from the Andaman Sea coast of Thailand. The species is very small, generally less than 1 mm long in sexually mature animals. It is found exclusively on the leaves of the seagrass Halophila ovalis and accordingly we name it Ercolania halophilae n. sp. Anatomy and histology have been studied by serial sectioning and 3D-reconstruction. This is the first limapontioid species studied in full 3D-microanatomical detail. Ercolania halophilae shows several special features. A heart and pericardium are absent, as is also seen in a few other species of Sacoglossa. Salivary glands are very prominent and unequal on left and right sides. There is a system of highly vacuolated cells situated along the main digestive gland tubules. Those cells are apparently associated with the kidney and we assume that they are involved in excretion. Radular teeth are sabot-shaped and more similar in shape to those of the enigmatic Japanese Alderiopsis nigra than to any known species of Ercolania. The reproductive system is typical limapontiid, with a closed seminal receptacle, a penetrant penial stylet and a bilobed prostate gland. Branches of the albumen gland enter the cerata, as seen in some but not all species presently referred to Ercolania. We therefore place the species in Ercolania rather than the poorly defined Alderiopsis. We briefly compare limapontiid genera and show that revision is needed.

A new species of Mictyris Latreille, 1806 (Crustacea: Decapoda: Brachyura: Mictyridae) from the Andaman coast of Thailand, with notes on its ecology and behavior.

A new species of soldier crab (genus Mictyris Latreille, 1806) is described from the Andaman Sea coast of Thailand. Mictyris thailandensis sp. nov. differs morphologically from its described congeners by its pale plain colouring, the differently shaped apex of the male first gonopod, and by chela features. It also has significant genetic divergence (cytochrome oxidase I > or = 11.95%) from other described species.

Potential of remote sensing techniques for tsunami hazard and vulnerability analysis – a case study from Phang-Nga province, Thailand

Abstract. Recent tsunami disasters, such as the 2004 Indian Ocean tsunami or the 2011 Japan earthquake and tsunami, have highlighted the need for effective risk management. Remote sensing is a relatively new method for risk analysis, which shows significant potential in conducting spatially explicit risk and vulnerability assessments. In order to explore and discuss the potential and limitations of remote sensing techniques, this paper presents a case study from the tsunami-affected Andaman Sea coast of Thailand. It focuses on a local assessment of tsunami hazard and vulnerability, including the socio-economic and ecological components. High resolution optical data, including IKONOS data and aerial imagery (MFC-3 camera) as well as different digital elevation models, were employed to create basic geo-data including land use and land cover (LULC), building polygons and topographic data sets and to provide input data for the hazard and vulnerability assessment. Results show that the main potential of applying remote sensing techniques and data derives from a synergistic combination with other types of data. In the case of hazard analysis, detailed LULC information and the correction of digital surface models (DSMs) significantly improved the results of inundation modeling. The vulnerability assessment showed that remote sensing can be used to spatially extrapolate field data on socio-economic or ecological vulnerability collected in the field, to regionalize exposure elements and assets and to predict vulnerable areas. Limitations and inaccuracies became evident regarding the assessment of ecological resilience and the statistical prediction of vulnerability components, based on variables derived from remote sensing data.

Post Tsunami Job Satisfaction Among the Fishers of Na Pru Village, on the Andaman Sea Coast of Thailand

The paper examines job satisfaction among fishers in a tsunami-impacted area on the Andaman coast of Thailand. Following the tsunami, many predicted that fishers would be reluctant to resume their fishing activities. Observations in the fishing communities, however, indicated that as soon as fishers obtained replacements for equipment damaged by the tsunami, they began to fish again. Nevertheless, most fishers reported they would change fishing type, and that if they had the opportunity they would leave fishing altogether. Whether or not these attitudes can be attributed solely to the impacts of the tsunami is not clear at this point, but this supposition is provided some support from data collected from small scale fishers in two towns near Bangkok in the Gulf of Thailand which reflected more positive attitudes towards the occupation. While attitudes towards the occupation are more negative than those reported for many other fisheries, the scores for the job satisfaction categories indicated that the sample means for all job satisfaction categories except Self-Actualisation are above the midpoint on the scales. This, in turn, indicates general satisfaction with the occupation—perhaps the challenge and adventure of the job are perceived as being a little too much following on the heels of the Indian Ocean tsunami that devastated the area. Hence, although fishers say that they would leave the occupation for another, it is unlikely that they will unless the alternate occupation, at the very least, meets the satisfactions provided by fishing.

Holocene sea levels along the Andaman Sea coast of Thailand

For the Malay-Thai Peninsula several sea-level curves for the younger Holocene, based on field evidence as well as on hydro-isostatic modelling of a far-field site, have been published. The general assumption is a rapid rise to a mid-Holocene maximum up to +5 m above present sea level, followed by a constant or oscillating regression. However, from the Andaman Sea coast of Thailand, which was affected by the 2004 tsunami, only isolated observations are available regarding Holocene sea levels. Thus, the timing and magnitude of the Holocene highstand as well as the course of the regression remain to be defined. As several palaeotsunamis could be detected in the meantime it is important to know the related sea levels as exactly as possible to judge the energy, inundation width and potential wave height of these events. Therefore, fixed biological indicators from the rocky coasts of the Phang-nga Bay and Phuket, as well as morphological indicators from beach-ridge and swale sequences along the exposed west coast (Ko Phra Thong) were studied, to gain information about the Holocene sea-level development in this region. While oyster and coral data from the Phang-nga Bay and Phuket document a Holocene maximum of +2.6 m at 5700 cal. BP, the ridge crests and swale bases in the northwest of the study area point to maximum heights of +1.5–2.0 m above the present level around 5300 years ago. During the last 3000 years, to when the largest part of the Holocene palaeotsunami deposits from Thailand was dated, relative sea levels (RSL) in both areas did not exceed +1.5 m.

Monitoring post-tsunami vegetation recovery in Phang-Nga province, Thailand, based on IKONOS imagery and field investigations – a contribution to the analysis of tsunami vulnerability of coastal ecosystems

A major tsunami in December 2004 devastated the coastal ecosystems along the Andaman Sea coast of Thailand. Since intact coastal ecosystems provide many important services for local communities at the Andaman Sea, it is crucial to investigate to what extent (in terms of percentage area and speed) the affected ecosystems were capable of recovering after the tsunami. Field measurements and multi-date IKONOS imagery were used to estimate the recovery and succession patterns of coastal vegetation types in the Phang-Nga province of Thailand, three years after the tsunami. Thus, this study contributes to a holistic understanding of the ecological vulnerability of the coastal area to tsunamis. A zone-based change detection approach is applied by comparing two change detection techniques: the first method involves the calculation of a recovery rate based on multi-temporal TNDVI (transformed normalized difference vegetation index) images (TNDVI approach), whereas the second approach is a combined approach of the change vector analysis (CVA). Although these two methods provide different types of information (quantitative for the TNDVI approach, qualitative for the CVA), they are comparable in terms of results and accuracies. The results reveal that recovery processes vary based on the type of the ecosystem and, furthermore, are strongly influenced by human activities. Grasslands, coconut plantations and the mixed vegetation cover could recover faster than the mangroves and casuarina forests. Among the forest ecosystems, recovery rates of casuarina forests were higher than for mangroves, but the recovery area was smaller. This study also discusses the potential and some limitations and inaccuracies of applying high-resolution optical imagery for assessing vegetation recovery at a local scale.

The post-depositional changes of the onshore 2004 tsunami deposits on the Andaman Sea coast of Thailand

The Indian Ocean tsunami flooded the coastal zone of the Andaman Sea and left tsunami deposits with a thickness of a few millimetres to tens of centimetres over a roughly one-kilometre-wide tsunami inundation zone. The preservation potential and the post-depositional changes of the onshore tsunami deposits in the coastal plain setting, under conditions of a tropical climate with high seasonal rainfall, were assessed by reinvestigating trenches located along 13 shore-perpendicular transects; the trenches were documented shortly after the tsunami and after 1, 2, 3 and 4 years. The tsunami deposits were found preserved after 4 years at only half of the studied sites. In about 30% of the sites, the tsunami deposits were not preserved due to human activity; in a further 20% of the sites, the thin tsunami deposits were eroded or not recognised due to new soil formation. The most significant changes took place during the first rainy season when the relief of the tsunami deposits was levelled; moderate sediment redeposition took place, and fine surface sediments were washed away, which frequently left a residual layer of coarse sand and gravel. The fast recovery of new plant cover stabilised the tsunami deposits and protected them against further remobilisation during the subsequent years. After five rainy seasons, tsunami deposits with a thickness of at least a few centimetres were relatively well preserved; however, their internal structures were often significantly blurred by roots and animal bioturbation. Moreover, soil formation within the deposits caused alterations, and in the case of thin layers, it was not possible to recognise them anymore. Tsunami boulders were only slightly weathered but not moved. Among the various factors influencing the preservation potential, the thickness of the original tsunami deposits is the most important. A comparison between the first post-tsunami survey and the preserved record suggests that tsunamis with a run-up smaller than three metres are not likely to be preserved; for larger tsunamis, only about 50% of their inundation area is likely to be presented by the preserved extent of the tsunami deposits. Any modelling of paleotsunamis from their deposits must take into account post-depositional changes.

Tsunami risk and impacts on coastlines

Tsunami waves represent extreme often catastrophic events, which significantly and adversely impact coastal areas. In spite of the lower frequency of occurrence comparing to storms and storm-induced surges, tsunami-induced coastal flooding often leads to massive casualties and tremendous economic losses. Hence, although tsunamis are a rare event, they often come in the form of a high-impact natural disaster. This Special Issue on Tsunami Risk and Impacts on Coastlines comprises ten papers by an international group of authors. The first paper is titled ‘‘The earthquakes and related tsunamis of October 6, 1944 and March 7, 1867, NE Aegean Sea’’ and is written by Altinok et al. The second paper is authored by Alpar et al. and deals with new approaches in the assessment of tsunami deposits in Dalman, SW Turkey. The third paper, by Lopez et al., has the title ‘‘Evidence for mid to late Holocene paleotsunami deposits, Kakawis Lake, Vancouver Island, British Columbia.’’ The fourth paper which is on the far field impact and coastal sedimentation associated with the 2006 Java tsunami in West Australia is by Prendergast and Brown. A corrected 3-D SPH method for modeling breaking tsunami waves by Xie et al. is the theme for the fifth paper. The sixth paper by Rajakumari and Subramanian deals with the topic of behaviour of tsunami waves along the coasts of Kancheepuram and Villupuram Districts in Tamil Nadu, India. The post-depositional changes to the onshore 2004 tsunami deposits on the Andaman Sea coast of Thailand are dealt with by Szczucinski in paper seven. Paper eight bears the title ‘‘Tsunami vulnerability assessment in urban areas using a numerical model and GIS’’ and is prepared by Usha et al. The evaluation of Canada tsunami risk and numerical modeling for potential tsunamis along western Canada coast is the focus of the ninth paper by Xie et al. The final paper is written by Murthy et al. and is about mapping of coastal inundation along Nagapattinam based on field observations. The guest editors would like to express their gratitude to Springer for inviting them to guest-edit this Special Issue, and they hope that this will contribute to the knowledge and understanding of the tsunami risk and the coastal impacts that they generate.

Evidence of probable paleotsunami deposits on Kho Khao Island, Phang Nga Province, Thailand

The 2004 tsunami deposits and probable paleotsunami deposits were studied at the southern Kho Khao Island, on Andaman Sea coast of Thailand. The 2004 tsunami laid down about 8 cm of fining upward medium sand and locally about 40 cm of massive coarse sand with common mud clasts. The sediments were characterized by the presence of marine foraminiferal assemblage; however, already after 5 years many of carbonate foraminiferal tests were partly or completely dissolved. The probable paleotsunami deposits form layer about 1 m thick. It consists of massive very coarse sand with common big shells and mud clasts. Its composition suggests a marine origin and the presence of mud clasts, and similarity to the 2004 tsunami deposits suggests that the layer was left by paleotsunami, which took place probably during the late Holocene, even though two shells within the layer gave 14C ages of 40,000 years or more.

Post-tsunami rehabilitation of fish cage farms on the Andaman coast of Thailand

A post-tsunami rehabilitation of cage culture along the Andaman Sea coast of Thailand was carried out in five provinces (Ranong, Phang-nga, Krabi, Trang and Satun) from September 2007 to February 2008. Based on the survey conducted, the money compensated subsequently used to buy materials for cage re-construction and cage repair accounted for 28.1% of the total, and to buy seed, feed and chemicals for culture operations, 15.8%. A surprising finding is that 56.1% of compensated money was used for other purposes. The analysis showed that the quality and quantity of equipment, seeds and feeds invested in aquaculture farms were increased in comparison with the pre-recovery period. Importantly, the farm area, growth rate, amount of product and revenue were improved during the post-tsunami rehabilitation period. Additionally, the area and quality of houses, household consumption, household infrastructures, health care and education were also improved. The satisfaction level of cage farmers in regard to the recovery programs was high (weigh average index = 3.88). The results from this study showed that the net economic profit (NEP) achieved was 41,030.49 baht/crop (33.9 baht = 1 US$) for sea bass culture, while NEP for grouper culture was 59,529.98 baht/crop. The result from the present study indicated that the economic value of cage culture farms was profitable. However, the seed shortage, high cost of trash fish, disease outbreak and marketing were among key problems and constraints encountered. In this study, we also found that the knowledge about fish marketing and culture techniques was poor. Therefore, technical, marketing and financial support are required for the future.

Using remote sensing to assess tsunami-induced impacts on coastal forest ecosystems at the Andaman Sea coast of Thailand

Abstract. The December 2004 tsunami strongly impacted coastal ecosystems along the Andaman Sea coast of Thailand. In this paper tsunami-induced damage of five different coastal forest ecosystems at the Phang-Nga province coast is analysed with a remote sensing driven approach based on multi-date IKONOS imagery. Two change detection algorithms, change vector analysis (CVA) and direct multi-date classification (DMC), are applied and compared regarding their applicability to assess tsunami impacts. The analysis shows that DMC outperforms CVA in terms of accuracy (Kappa values for DMC ranging between 0.947 and 0.950 and between 0.610–0.730 for CVA respectively) and the degree of detail of the created change classes. Results from DMC show that mangroves were the worst damaged among the five forests, with a 55% of directly damaged forest in the study area, followed by casuarina forest and coconut plantation. Additionally this study points out the uncertainties in both methods which are mainly due to a lack of ground truth information for the time between the two acquisition dates of satellite images. The created damage maps help to better understand the way the tsunami impacted coastal forests and give basic information for estimating tsunami sensitivity of coastal forests.