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1.
Benjamin Ezekiel Bwadi Firuza Begham Mustafa Mohammad Lokman Ali Subha Bhassu 《Singapore journal of tropical geography》2019,40(1):71-91
Finding potential sites for resilient prawn production in the tropical environment that also prevents wastage of natural resources is not an easy task. The purpose of this study is to evaluate water quality suitability for prawn farming in Negeri Sembilan of Peninsular Malaysia based on Geographic Information System (GIS). To achieve this goal, numerous criteria including sources of water, water temperature, water pH, sources of pollution, salinity, soil texture and availability of phytoplankton criteria were considered for the modelling process. Analytic Hierarchy Process (AHP) technique was performed to standardize the criteria and the weighting process. The weighted overlay of indicators and results were accomplished by applying the Multi‐Criteria Decision Analysis (MCDA) method in GIS. It was indicated that the Negeri Sembilan area has potential for prawn farming. The results showed that about 25 per cent (163 056.93 ha) of the area was most suitable for prawn farming, about 58 per cent (384 656.88 ha) was considered moderately suitable, while 18 per cent (117 633.49 ha) was regarded as least suitable. The study concluded that the multi‐criteria decision analysis of water quality for prawn farming is vital for regional economic planning in the Negeri Sembilan area and also significant when establishing a model for aquaculture development. 相似文献
2.
Kak Choon Loy Prakash Chandra Sinha Juneng Liew Fredolin Tangang Mohd Lokman Husain 《Natural Hazards》2014,70(1):23-37
Super typhoon Durian struck the central Philippines on November 30, 2006 and southern coast of Vietnam on December 5, 2006. The reported maximum wind exceeded 250 km/h, and the central pressure was 904 hPa during the peak of the system. The typhoon brought colossal damage, both in terms of lives and in terms of properties to the Philippines and Vietnam while Thailand and Malaysia were slightly affected. The energy from the high-velocity wind and central pressure drop resulted in the generation of storm surges along the coastal region of the Philippines including its surrounding islands as well as parts of southern Vietnam. In this paper, a numerical 2D model is used to study the oceanic response to the atmospheric forcing by 2006 super typhoon Durian in the coastal regions of the Philippines and Vietnam. The initial study of this model aims to provide some useful insights before it could be used as a coastal disaster prediction system in the region of South China Sea (SCS). The atmospheric forcing for the 2D model, which includes the pressure gradient and the wind field, is generated by an empirical asymmetrical storm model. The simulated results of storm surges due to typhoon Durian at two locations lie in the range of observed data/estimates published by the Joint Typhoon Warning Centre (JTWC). 相似文献
3.
ABSTRACTThe October 2011 sinking of the container ship MV Rena on Astrolabe Reef, New Zealand, provided a rare opportunity to examine the fate of shipwreck-derived contaminants on an offshore rocky reef and food chain. Analyses of trace metals, polycyclic aromatic hydrocarbons (PAHs) and organotins indicated significant but localised contamination of Astrolabe Reef but not of nearby Mōtītī Island. Three years after the grounding, PAH concentrations were greater in sediments at Astrolabe (up to 131?mg kg?1) than at control locations, while organotins from the ship's antifouling hull paint were found exclusively in Astrolabe Reef sediments and biota. Over 80% of Astrolabe sediment samples contained tributyltin at concentrations above guideline sediment levels (>0.07?mg kg?1). Tributyltin and its decomposition products were also recorded in sea urchins, gastropods, lobster and fishes at concentrations up to 0.2?mg kg?1. Wreck and cargo-derived metals, particularly copper, tin and zinc, were present in some Astrolabe sediment samples above Australia and New Zealand Environment and Conservation Council guideline concentrations. However, there appeared to be only limited transmission of metals through the food chain. Copper, tin and zinc were recorded at greater concentrations in Astrolabe sea urchins and gastropods compared to control specimens, while metal concentrations in other biota were comparable across impact and control sites. Despite over 3 years having passed since the Rena grounding, the data series does not show any upward or downward trends in contaminant concentrations on Astrolabe Reef. Consequently, there is uncertainty about the long-term implications of the Rena grounding for the ecology of Astrolabe Reef. 相似文献
4.
PM Ross RM Fairweather DP Culliford S Park CA Pilditch CN Battershill 《新西兰海洋与淡水研究杂志》2016,50(1):56-69
ABSTRACTTo investigate the uptake and depuration of polycyclic aromatic hydrocarbons associated with the Rena oil spill we sampled the surf clam Paphies subtriangulata at two open coast locations (6?km apart) just prior to oil coming ashore (7 October 2011), then at 1–3 week intervals for the next 4 months. Total polycyclic aromatic hydrocarbons (tPAH) increased at both sites from 1 to 96–124?µg?kg?1 (wet weight) by 18 October before declining to low levels (<4?µg?kg?1) by February 2012. Ongoing sampling throughout 2012–2014 included three additional sites to the north east (up to 30?km away) and a site 5?km to the south east revealing tPAH levels generally <10?µg?kg?1 except in October 2013 where levels ranged between 39–45?µg?kg?1 at all sites. A comparison of PAH component profiles with oil-contaminated beach sediment indicated that the high levels observed in surf clams between October–December 2011 were clearly associated with the Rena spill. However, the October 2013 peak had a PAH profile inconsistent with weathered Rena oil, suggesting an alternative source of contamination. Our results highlight the potential for P. subtriangulata as a PAH monitoring tool but recognise more study is needed to better quantify baseline levels and uptake and depuration dynamics. 相似文献
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6.
In the weeks following the 2011 Rena oil spill, a series of surveys was initiated on eight rocky intertidal reefs to describe the distribution of oil and to assess the impacts of oil on ecological communities. Consistent but relatively low cover of oil occurred at two sites (Mt Maunganui and Moturiki). The area covered by oil had decreased by c. 90% after 5 months due to natural weathering processes. There were immediate effects of oil fouling on the mussel Limnoperna pulex and its associated fauna, with reductions in the number of mussels and infaunal taxonomic richness. However, no ecological effects on any of the communities were detectable after 1 month. Overall, the ecological effects of the Rena oil spill on rocky shore intertidal communities were small and not long-lasting, but we stress that this does not consider potential sublethal effects and their consequences on organisms. 相似文献
7.
Lake Manapouri in the South Island of New Zealand has a significant hydroelectric generation facility, which potentially has a negative impact on the successful emigration of longfin eels (Anguilla dieffenbachii) from the upper Waiau catchment. Consequently, a trap-and-transfer programme has been implemented to allow silver (migratory) eels access to the sea. The present study analysed data on the timing of captures and numbers of silver eels over four seasons, including the influence of possible migration cues. Silver eels were captured over an extended season of seven months (November–May), with peak numbers during December and January. Flow at the lake outflow was found to have a weak relationship with the number of eels caught, as did lake level, but moon phase and rainfall had no significant effect. These results highlight the variability in silver longfin eel behaviour both in terms of timing and response to potential environmental cues. 相似文献
8.
Ali Mirzaei Fredolin Tangang Liew Juneng Muzneena Ahmad Mustapha Mohd Lokman Husain Mohd Fadzil Akhir 《Ocean Dynamics》2013,63(8):961-977
This study investigates long-term variability and wave characteristic trends in the southern region of the South China Sea (SCS). We implemented the state-of-the art WAVEWATCH III spectral wave model to simulate a 31-year wave hindcast. The simulation results were used to assess the inter-annual variability and long-term changes in the SCS wave climate for the period 1979 to 2009. The model was forced with Climate Forecast System Reanalysis winds and validated against altimeter data and limited available measurements from an Acoustic Wave and Current recorder located offshore of Terengganu, Malaysia. The mean annual significant wave height and peak wave period indicate the occurrence of higher wave heights and wave periods in the central SCS and lower in the Sunda shelf region. Consistent with wind patterns, the wave direction also shows southeasterly (northwesterly) waves during the summer (winter) monsoon. This detailed hindcast demonstrates strong inter-annual variability of wave heights, especially during the winter months in the SCS. Significant wave height correlated negatively with Niño3.4 index during winter, spring and autumn seasons but became positive in the summer monsoon. Such correlations correspond well with surface wind anomalies over the SCS during El Nino events. During El Niño Modoki, the summer time positive correlation extends northeastwards to cover the entire domain. Although significant positive trends were found at 95 % confidence levels during May, July and September, there is significant negative trend in December covering the Sunda shelf region. However, the trend appears to be largely influenced by large El Niño signals. 相似文献
9.
The subtidal sediments of four coastal environments (beach, berm, surf zone and nearshore sea floor) of Kuala Terengganu have
been studied in terms of their textural characteristics and depositional process. Sampling and statistical analyses of the
grain size distributions of beach, surf zone and shallow sea-floor sediments at various locations along the coastline show
that they varied in their mean grain size as well as values of sorting and skewness. The statistical parameters of grain size
distributions thus allowed recognition of distinct sub-environments. The size distribution of such sediments suggests that
the various processes that are responsible for their transportation and deposition are wave, current and wind action. The
different energy conditions and the morphology of each coastal environment seem to be reflected in the characteristics of
the sediments in each environment. 相似文献
10.
There is increasing evidence that the global climate is changing as a result of anthropogenic activity. Short‐term mean, maximum, and minimum temperatures of the city Rize located at the Eastern Black Sea Coast of Turkey were analyzed to reveal trends, change points, significant warming (cooling) periods, and trend rates per year. An increasing trend of approximately 1.27°C/33 years (α = 0.001) in the annual mean temperatures is found during the period from 1975 to 2007. Two periods, averaging 13.78 and 14.66°C, respectively, were detected from fluctuation in the annual mean temperatures. The trend of the first period (1975–1993) is towards a cooler climate, whereas the trend of the second period (1994–2007) is towards a warmer climate. Summer, autumn and, particularly, the spring mean temperatures have tended to increase strongly, whereas the winter mean temperatures have increased slightly over the whole period. For the winter mean temperature, the trend rate indicates a slight increase, which is insignificant. Maximum temperatures have dramatically increased with 1.61°C (α = 0.001) over the last 33 years. However, annual minimum temperatures have increased by 0.99°C (α = 0.01) over the same period. 相似文献