Abstracts of Undergraduates Dissertations-UWU

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Browsing Abstracts of Undergraduates Dissertations-UWU by Subject "Aquatic Resources Technology Degree Programme ( AQT)"

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    Abundance and Diversity of Valithondal Coral Reef in Jaffna Penisular and Current Impacts
    (Uva Wellassa University of Sri Lanka, 2016) Raveendrakumar, N.
    Coral reefs are one of the most important marine habitats in shallow tropical seas. However, there are no proper scientific records on the status of the Valithondal coral reef in Northern, Sri Lanka. Therefore, the present study was carried out to identify the abundance and diversity of Valithondal coral reef at Northern coastal waters of Sri Lanka from January 2021 to May 2021. Coral Video Transects (CVT) method was carried out for sampling at the selected location assigned by the criteria of the species abundance and water clearance where water depth less than 5m by snorkeling over 100m transect lines, which covered 10m x 100m area. Altogether 69 macro-species were recorded comprising twenty-three species of hard corals, seven species of soft corals, nine species of green seaweeds, seven species of brown seaweeds, five species of red seaweeds, thirteen species of fishes, and five species of mollusks. Species richness, Shannon-H index, and Simpson's diversity index were 29, 3.113, and 0.9428 respectively. Comparatively, a medium diversity of coral families was recorded. Families Faviidae, Merulinidae, Acroporidae, Montastraeidae, Pocilloporidae, Leptastrea, and Poritidae are the hard corals. There is one soft corals under the family Alcyonidae. Green brown, and red seaweed species were identified under three, two, and three families respectively. The families of the green seaweeds were Caulerpaceae, Halimedaceae, and Ulvaceae, brown seaweeds were Dictyotacea and Sargassaceae, and red seaweeds were Liagoraceae, Gracilariaceae, and Halymeniaceae. Identified fishes were included under six families; Chaetodontidae, Lutjanidae, Pomacentridae, Serranidae, and Haemulidae while molluscs are included in five families which are Buccinidae, Terebridae, Trochidae, and Muricidae. The highest species diversity was observed in the family Merulinidae (12.72%), Caulerpaceae (10.90%), and Alcyonidae (7.27%) and followed by Chaetodontidae (5.45%). The most abundant species were Acropora cytherea and Porites lobata in hard coral species, which is contributed to reef recovery in Sri Lanka. The other high abundant species are Lobopyton sp. and Sinularia sp. in soft coral species, Caulerpa lentilliferca, Caulerpa parvula, Canistrocarpus crispatus, Padina boergesenii and Halyrnenia durvillei in seaweed species, Chaetodontidae and Pomacentridae in fish species. The results highlighted that the high biodiversity and abundance of macro-species recorded in the Valithondal coastal waters, which would be protected by forcing effective management practices. Further studies are also needed to the sustainabilitlf of the coral reef ecosystem. Keywords: Corals; diversity indices; hard coral; macro-species; molluscs; seaweeds; soft coral
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    Abundance and Diversity of Ichthyoplankton in the West Coast of Sri Lanka, from Kelani River Estuary to Maha Oya Estuary
    (Uva Wellassa University of Sri Lanka, 2014) Silva, A.P.R.
    Fundamental understanding of fish resources has become an urgent need in Sri Lanka for the sustainable management of fish stocks. A preliminary study was carried out with the aim to find the abundance, distribution and diversity of ichthyoplankton in the west coast. Samples were collected in five stations bordering Kelani river estuary, Negombo lagoon and Maha Oya estuary in the west coast. A horizontal surface sample and a vertical sample were collected from each station using Working Party 2 (WP2) plankton net (180 wn mesh size) for three months in 2018: March, September and October. Fish eggs and larvae were separated and identified to the lowest possible taxonomic level under the stereo microscope using the standard keys. A total of 4095 fish eggs from which 3 families: Clupeidae, Engraulidae and Cynoglossidae were able to identify. And 465 fish larvae belonged to 23 families from which 19 were demersal. The 5 most abundant larval families recorded from the study site were Siganidae (30%), Blenniidae (28%), Clupeidae (7%), Gobiidae (5%) and Engraulidae (4%). An average abundance of 8.772 /m3 eggs and 0.996 /m3 larvae were recorded. The results of one-way ANOVA revealed that the spatial variation of larval abundance was significant (P<0.05). The highest abundance of fish eggs was found at station three (22.158 /m3 in vertical sample and 13.934 /m3 in horizontal surface sample). Further, egg abundance was found to be highest in March. Highest larval abundance (1.196 /m3 in vertical sample and 2.537 /m3 in horizontal surface sample), number of families (19), Simpson index (0.261), richness (8.584) and dominance (0.755) were recorded at station four which is located adjacent to Negombo lagoon mouth and Maha Oya estuary. This study infers that there is a high pelagic and demersal fish diversity and abundance in the west coast of Sri Lanka. Since this is a preliminary study, comprehensive studies on the spatial and temporal variation of abundance and diversity of ichthyoplankton in Sri Lankan waters are recommended. Keywords: Ichthyoplankton, Fish Larvae, Fish Eggs, West coast, Sri Lanka
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    ACUTE TOXIC EFFECTS OF DIAZINON AND ETOFENPROX ON ZEBRAFISH (Danio rerio) EMBRYOS
    (Uva Wellassa University of Sri Lanka, 2016) WIJETHUNGA, K.A.N.L.
    Pesticides severely affect the balance in biodiversity, but are used worldwide for agriculture to control pests. The effect of this on the life in water bodies has been poorly investigated. The present study investigated the acute toxicity of two widely used pesticides; Diazinon (C12H21N203PS) and Etofenprox (C25H2803) on zebrafish (Danio rerio) embryos, since the sensitivity of toxicology testing of zebrafish reveals the permissible limits in toxicants to the ecosystem. Fertilized zebrafish embryos were exposed to a series of concentrations of pesticides (below 100 mg L-1 for Etofenprox and below 10 mg LI for Diazinon) which was prepared according to the results of the range finding test. Deionized water was used as an internal plate control and negative control whilst 15% ethanol was used as positive control. Four apical observations of coagulation of fertilized eggs, lack of somite formation, lack of detachment of the tail bud from the yolk sac and lack of heartbeat at 24, 48, 72 and 96 hours were recorded as an indicator for lethality according to OECD / OCED 236; guideline for the test of chemicals, Fish Embryo Acute Toxicity (FET) test. Results indicated that the median lethal concentration (LC50) of Diazinon and Etofenprox at 96 hours for zebrafish embryos were 1.975 mg 1:1 and 4.800 mg L-1 respectively. Shrinkage of chorion, growth retardation, lack of tail formation, yolk sac edema, hemorrhages, pericardial edema, lack of pigmentation were most potential sub lethal and teratogenic deformities in treated embryos with Diazinon and Etofenprox. An increasing trend of mortality rate with the pesticide concentration and the decreasing trend of LC50 with the exposure time were observed in the present study. Results revealed that exposing zebrafish embryos to minor concentrations of Diazinon (1.975 mg 1:1) and of Etofenprox (4.800 mg L-1) can directly affect the survival and embryonic development of zebrafish, it can be used as a cost effective method to assess the hazard potential of pesticides in aquatic bodies. Keywords: LC50, Toxicology, Sub lethal, Deformities
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    Analysis of Functional Properties of Fish Protein Hydrolysates from Scomber Japonicus Canned Fish Processing Fin Wastage
    (Uva Wellassa University of Sri Lanka, 2013) EDIRIWEERA, T.K.
    Pacific chub mackerel (Scomber japonicas) is a salience fish species which highly utilized in canned fish processing. In production, around 30% of raw fishes are discarded as wastes which leads to economic losses and environmental pollution. Hence, production of Fish Protein Hydrolysates (FPH) utilizing fish wastes, which contains bioactive compounds may be an ideal remedy. In this study Scomber japonicus canned fish processing fin wastage was collected and blended. Aqueous extracts of Fish Protein Concentrates (FPC) were produced with 04 different ratios as sample: distilled water, 1:1, 1:2, 1:3 and 1:4. Crude extraction was observed using 10% SDS-PAGE. Extracted FPCs were hydrolyzed using Papain, Pepsin, Trypsin and Protease enzymes (1:100) under 37°C with their optimum pH conditions for 0, 3, 6, 9, 12 and 24 hours followed by heat inactivation at 100°C for 15 minutes. Hydrolyzed samples were lyophilized and observed for antioxidant activities by TBARS and DPPH scavenging assay, metal chelation activity by Fe (II) chelating activity and antibacterial activities by agar well diffusion method. According to the observations there was no significant difference between the 04 ratios in yield (p>0.05). So 1:1 ratio was selected with periods as Papain-24 h, Pepsin-3 h, Trypsin-3 h, Protease-0 h for further experiments. According to the results obtained from TBARS assay, none of the FPHs showed antioxidant properties (p<0.05), insttad all demonstrated high oxidative activity. However DPPH scavenging assay showed significant difference among the treatments (p<0.05). Results obtained by Fe (II) chelation activity analysis revealed that the produced FPHs show Fe(II) releasing activity instead of chelation (1.84, 13.99, 16.48, 1.84%,), while FPHs produced according to standard protocol showed a slight chelating activity (0.73%). Further, the results of antibacterial activity against E.coli and Salmonella spp. was highly positive in all four types of hydrolysates and the best activity against both strains was demonstrated by Trypsin hydrolysate. This concludes the FPHs produced using aqueous extracts of Scomber japonicus contain strong antibacterial activity, though they do not contain strong antioxidant activity and they have iron releasing properties. Keywords: Fish Protein Hydrolysates (FPH), Enzymes Treatment, Antioxidant, Metal Chelating, Antibacterial
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    AN ANALYSIS OF RECENT TRENDS OF SMALL MESHED GILLNET FISHERY IN WEST COAST OF SRI LANKA
    (Uva Wellassa University of Sri Lanka, 2013) DISSANAYAKE, D.M.I.M.
    An analysis of recent trends of small meshed gill net fishery in West coast of Sri Lanka is presented by this study. Approximately 93% of the surveyed sample is represented by FRP boats. Around 60% of total fishing effort on coastal pelagic resources in the study area in terms of number of boat days is provided by small meshed gill nets. The duration for which gillnet in operation (true fishing time) is normally 0.5 to 3 hours and present, the fishing depth range has become much wider and it is between 5 to 90m. FRP boats bring 3 to 42 net pieces of gillnets per fishing operation. The best fishing season in the west coast is at the latter part of the south west monsoon and higher catches are obtained in August and September. The major target fish group in small pelagic fishery in the west coast is clupeids and Ambligaster sirm is the dominant species in the catches over the considered period of time and it provides around 46% of the total catch in the west coast. The annual CPUE in terms of kilogram per net piece per day has varied on a range of 2 to 3.5 and CPUE in terms of kilogram per boat per day has varied on a range of 40-70. Though there is an increasing trend in the CPUE in terms of catch in kilogram per boat per day, it does not imply that there is a high abundance of fish in the studied area because this achievement may possible due to the increased usage of gillnet pieces, usage of high engine power, long fishing time and increased depth of fishing. Key words: Recent trend, Small pelagic, Small meshed gillnets, West coast
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    An Analysis of Supply Chain of Small-Scale Fisheries in Loggal Oya Reservoir in Badulla, Sri Lanka.
    (Uva Wellassa University of Sri Lanka, 2016) Dissanayake, D.M.W.C.J.
    Loggal Oya Reservoir is one of the minor perennial tanks located in Badulla District, which has higher production rate compared to other minor perennial tanks in the area. However, the supply chain performance, fisheries activities and livelihood condition are not up to the standard level. The current study attempts to recognize the present condition of the fisheries supply chain along with its main stakeholders and their selected socio¬economic characteristics. Moreover, the study also focuses on recognizing the constrains and opportunities related to small scale inland fishery supply chain in Loggal oya reservoir. Primary data were collected using a questionnaire from 59 individuals and while qualitative data was collected through Key Informant Interviews (KIIs) and Focus Group Discussions (FGDs). Additionally, secondary data from various source have also been used and mainly descriptive analysis was employed to accomplish the objectives of the study. Specifically, BCG Matrix, SWOT analysis and Fishbone analysis were used to analyze the supply chain while the Warwick — Edinburgh Mental Wellbeing Scale were used to examine the Wellbeing of the stakeholders. The study reveals that the Loggal Oya fishery supply chain consists of four main stakeholder groups such as fishermen, wholesalers, retailers, and consumers. It is observed that 64% fishermen sell their catch to wholesalers, whereas 34% directly sell their catch to consumers and 2% of the fishermen sell their catch to small-scale value-added producers. In contrast, the study reveals that 60% wholesalers sell their fish to retailers, while 40% sell and transport their fish catch to local markets located in Badulla and Mahiyangana.100% retailers directly sell their fish to consumers. The majority of the stakeholders had a moderate wellbeing in the study area. The analysis further highlighted constrains such as depletion of fish stock, lack of financial availability, lack of training, knowledge and new technologies, and lack of infrastructure facilities in the fisheries supply chain in Loggal oya reservoir. The study emphasizes the requirement of providing appropriate trainings, credit facilities and funds, infrastructure facilities and inputs, improve market facilities, enhance security around the lake and awareness programs as remedies to the recognized constrains. Moreover, the study also recommends promoting value-added production based on fish in order to improve the supply chain and livelihood condition of the stakeholder.Key words: Supply chain analysis; Small-scale fisheries; Inland fishery; Wellbeing
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    ANALYZE HISTAMINE LEVEL IN VARIOUS POSITIONS OF HISTAMINE DEVELOPED TUNA FISH
    (Uva Wellassa University of Sri Lanka, 2014) KALUBOWILA, K.S.H.
    Histamine is a simple chemical substance which is derived from Histidine by the enteric bacteria. Presence of high Histamine in fish meat causes allergic conditions to the consumers. Fair knowledge of Histamine levels in various positions of Tuna fish increases the probability of selecting good quality fish with low Histamine level. Objectives of this study were to analyze the Histamine levels in various positions of Histamine developed in Tuna fish, to find out the effectiveness of Histamine knowledge related to the positions of Tuna fish currently used in industry and to acknowledge the fish processing companies to minimize the income losses. Histamine levels of 30 individual fish were analyzed by ELISA method. 3 positions of each fish were subjected to be analyzed. After preceding a questionnaire type survey with fifteen fin fish processing companies in Sri Lanka, three positions of Tuna were selected to take the samples for analyzing histamine levels. Based on the highest mean levels of each position, the best position to taking histamine test was selected. In the belly area of Tuna fish has the highest Histamine level with 25.74 ppm mean value and the tail area of Tuna fish has the lowest Histamine level with 9.20 ppm mean value. Results of these studies indicate that the best position to take sample for Histamine test from Tuna fish, is near the belly area and taking sample from the tail area of Tuna fish has low effectiveness. According to the results there is no significant difference among Histamine level in the belly area of Tuna fish and Histamine level beneath pectoral fin of Tuna fish. Further studies need to be carried out to investigate the relationship between Histamine levels of Tuna fish and the different fishing areas of the Sri Lankan Ocean.
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    ANTIMICROBIAL ACTIVITY OF SELECTED MARINE PLANTS IN SOUTH WEST COAST OF SRILANKA
    (Uva Wellassa University of Sri Lanka, 2013) ARULANANTHAN, A.
    Natural products from marine plants are known to have a variety of biological properties including antimicrobial activity. Even though these activities are well known, only a limited number of studies have assessed the antimicrobial properties of extracts from marine vegetation in Sri Lanka. To address this issue, the antimicrobial activity of extracts from selected algae and a seagrass species were tested. Samples were collected from the Barberyn reef off Beruwela coast and beach rocky platforms in Hikkaduwa. Using different solvents (chloroform, methanol, and water) natural products were extracted from four macroalgae species; Ulva pertusa, Gracilaria salicornia, Gracilaria hikkaduwensis and Padina minor, and a seagrass species Cymodocea serrulata. The antimicrobial activity of each extract was assayed by using agar well diffusion and agar disc diffusion method against two pathogenic bacteria Staphylococcus aureus (ATCC 29213) and Escherichia coli (DS 5a) and one yeast species Candida albicans (Bench culure) Testing was carried out for varying quantities of extracts (1 mg, 2 mg and 5 mg for disc diffusion; 5 mg, 10 mg and 20 mg for well diffusion). The antimicrobial activity of extracts was comparable with Kanamycin and fluconazole which were used as positive controls for antibacterial and antifungal activity respectively. Methanol and chloroform extracts of C.serrulata and G. hikkaduwensis showed antibacterial activity against S.aureus. Chloroform extract of Upertusa showed antimicrobial activity against S.aureus and C. albicans. Additionally, chloroform extract of C.serrulata gave positive results against C. albicans. The maximum antibacterial activity was observed in the methanol extract of C.serrulata of 11 mm and minimum activity was 0.33 mm observed in chloroform extract of G. hikkaduwensis against S. aureus. Water extracts did not show antimicrobial activity. The results from this study confirm antimicrobial activity in C.serrulata, Upertusa and G.hikkaduwensis found in Sri Lanka. Further research is needed to identify the individual compounds responsible for antimicrobial activity, which may in turn lead to developing therapeutic drugs from locally available marine vegetation. Key words: antimicrobial activity, seaweed, bioactive, solvent extracts
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    Applicability of Brown Seaweed Species (Sargassum crassifolium) for Treating Lobster Farm Waste Water
    (Uva Wellassa University of Sri Lanka, 2016) Kanagaradnam, P.
    Waste water generation in aquaculture farms, including all lobster culture practices are a serious issue in the industry. The present study was carried out at lobster farm located at Northern Province in Sri Lanka. Approximately 756,000 L of waste water is generated on this farm annually and discharges waste water without proper treatments to the natural environment. The waste water discharged from the lobster farm consists of organic and inorganic chemical components that can be caused potential environmental problems. Present study focused on investigate applicability of Brown seaweed, Sargassum crassifolium biomass to efficient removal of nutrients from the lobster farm waste water. The S. crassifolium abundant in Northern Province, Sri Lanka. Seaweed biomass optimization was performed by three different seaweed biomasses, viz., 20 g, 30 g and 40 g and then 20 g (1 g L-1) identified as the efficient seaweed biomass. Initial physicochemical parameters of the waste water pH, Temperature, Salinity, Dissolved Oxygen, Biological Oxygen Demand, Ammonia, Nitrite, Nitrate and Phosphate were analyzed using the standard methods. Then collected waste waters were transferred to six glass tanks of 50 L capacity each. The seaweed was used at 1 g L-1 density in each tank except in the control tank. Three replicates were used. Ammonia, Nitrite, Nitrate and Phosphate were analyzed once in three days from beginning to the end of the treatment period (28 days) to investigate the initial waste water final qualities and quality changes after Phycoremediation. Final quality of Waste water, physiochemical parameters pH (7.4), Temperature (29°C), Salinity (36 ppt), Dissolved Oxygen (5.74 mg L-1), Biological Oxygen Demand (95 mg L-1). S. crassifolium removed 1.194 ± 0.34 mg L-1 of Ammonia, 0.129 ± 0.03 mg L-1, of Nitrite, 0.147 ± 0.04 mg L-1 of Nitrate and 2.40 ± 0.72 mg L-1 of Phosphate. Nutrient removal amounts were significantly differed (P<0.05) between control and after seaweed treatment. The weight gains of S. crassifolium during the study period was 8.7 g of biomass of S. crassifolium. Thus, the seaweed has been utilized the nutrients present in the discharged waste waters. The results of the study concluded that the nitrogen and phosphorus in the lobster farm waste waters, can be effectively removed through S. crassifolium. Keywords: Lobster, Sargassum crassifolium, Seaweed, Phycoremidiation.
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    APPLICATION OF GIS TO IDENTIFY POTENTIAL AREAS FOR AQUACULTURE IN BADULLA DISTRICT , UVA PROVINCE
    (Uva Wellassa University of Sri Lanka, 2013) SANDAMALI, M.A.N.
    Aquaculture is farming aquatic organisms including fish, mollusks, crustaceans and aquatic plants (FAO, 1990).The main intent of the present study is to highlight the role of Geographic Information System (GIS) in identification of potential areas for aquaculture in Badulla district, because GIS can use as powerful analytic and decision-making tool for the selection of potential and suitable site for aquaculture. The study was carried out in Badulla district, Sri Lanka located at longitude 80°.45 to 81°.15. Latitude 6°.34 to 7°.18. It covers an area of about 2,827 km2 . Secondary sources data have been collected and used to generate maps to identify the fresh water bodies in Badulla district as seasonal tanks, perennial tanks, Stream network and rivers of Badulla district were developed. Water availability (proximity to rivers), soil texture, soil pH, rainfall, temperature and topography (slope, elevation) and land use factors were considered to identify potential areas for aquaculture (pond culture). Water availability, soil texture, soil pH, slope, elevation, rainfall, temperature, land use/ land cover thematic layers were created using ArcGIS 10.1 software. All these thematic layers have been assigned the' weights according to their relative influence on pond construction using Analytic Hierarchy Process (AHP) and GIS approach. Finally, all thematic layers have integrated using map algebra in a ArcGIS 10.1 environment to generate an aquaculture potential map. Thus, four aquaculture potential areas have been Identified, viz. "Most suitable", "Suitable", "Fairly suitable", "Unsuitable". The north part of the Badulla district is identified as most suitable and the southern part of the Badulla district is identified fairly and unsuitable for aquaculture. The study thus demonstrates that GIS is very useful tool for delineating aquaculture potential areas in Badulla district. Key words: Aquaculture, Geographic Information System, Analytic. Hierarchy Process, potential area
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    ASSEMBLAGES OF PLANKTON IN TRINCOMALEE INNER HARBOUR BASIN, SRI LANKA
    (Uva Wellassa University of Sri Lanka, 2014) JAFSINA, M.I.
    Introduction of invasive alien plankton through ballast water is a major ecological issue in many countries in the world. Trincomalee harbour is one of the largest commercial port in east Asia due to its strategic location. Therefore, Trincomalee harbour is under risk of introducing alien species through the discharge of ballast water. As there are no local studies addressing this problem, the present study was carried out to gather baseline data of plankton in Trincomalee harbour. Three local sites including Trincomalee inner harbour, Trincomalee north harbour and Trincomalee south harbour were sampled. The plankton density, diversity and physico-chemical parameters of water samples were measured. Data on species density and physico-chemical parameters were analyzed using Pearson Correlation statistical tests as appropriate. There is a strong positive and negative relationship between species density and salinity. Altogether 127 taxa of plankton were found in the samples. Zooplanktons were categorized under 13 major groups and it was found that copepods, crustacean larva and ichthyoplankton were the major contributing groups towards zooplankton diversity and density. Diatoms comprised higher amount of the total phytoplankton population followed by dinoflagellates, Green algae and Blue green algae. The common diatoms were Chaetoceros sp. and Rhizosolenia sp. Some harmful algal bloom forming phytoplanktons were also observed. Through the study, 39.97 % of Skeletonema costatum was recorded and it is an indicator for eutrophication. Plankton abundance showed significant differences (P<0.05) with respect to their location (One way ANOVA) and plankton diversity did not showed significant differences (P>0.05) with respect to their location (One way ANOVA). Further, 47 plankton species were also , recorded from the study area that were not recorded in the literature and it was found that there are six species common to Tricomalee harbour basin and ships visited to Colombo harbour. Keywords: Ballast water, Alien species, Trincomalee harbour, Zooplankton, Phytoplankton
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    Assessing the Ecological Impact of the Bottom-Set Net Blue Swimming Crab (Portunus Pelagicus) Fishery on Non-Target Species in the Palk Bay (Jaffna District)
    (Uva Wellassa University of Sri Lanka, 2014) Vijayakumaran, S.
    The bottom-set crab net Portunus pelagicus fishery has recently developed and is now one of the top livelihoods of Thuraiyoor fishermen, which is located in Jaffna District inside the Palk Bay. The crab net fishery seems to be ecosystem friendly when compared with trawling. However a better understanding of the ecological impact is lacking in the Sri Lankan context. This study aimed to quantify the total bycatch, determine the catch composition of non-target species and examine the likely impact of the fishery on non-target species. Data were collected using a fishery dependent survey. From the total catch observed from the 152 net-sets, 45% of the catch was targeted catch and 55% was bycatch. The resulted proportion of bycatch as valuable bycatch (i.e. retained) and discarded bycatch were 40% and 15% respectively. Based on fishery dependent surveys, a total number of 84 non-target species were observed in the bycatch. The bycatch included 32 species of fish, 23 species of crustaceans, 18 species of mollusks, 9 species of echinoderms and 2 species of cnidaria. Among the total bycatch, spider conch (Lambis lambis) comprised 30% of the total catch by weight and identified as a main species. The remaining 25% included all other non-targeted species and the majority were mollusks and crustaceans. The automated Marine Sttwardship Council (MSC) vulnerability score and MSC overall score for spider conch were as 2.68 and 82 respectively, which is equivalent to an Unconditional Pass of the MSC Fishery Standard for Sustainable Fisheries. Consequently, this study at Thuraiyoor supports earlier studies in the Palk Bay, which indicate that the ecological impact on the non- target species by bottom-set crab net P. pelagicus` fisheries in the Palk Bay is a low conservation concern at present. Keywords: Bycatch, Portunus pelagicus, Bottom-set crab net, Palk Bay, Sri Lanka
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    ASSESSING THE RELATIONSHIP BETWEEN INDIAN OCEAN SEA SURFACE TEMPERATURE AND PRECIPITATION USING RAMA BUOY DATA
    (Uva Wellassa University of Sri Lanka, 2013) KALPAGE, R.P.P.
    Precipitation in the Indian Ocean associated countries depends on the monsoon winds, which is modulated by the intensity of the heating and cooling of the Indian Ocean. Sea surface temperature is an indicator of air-sea interaction, reflecting the heat fluxes in and out of the Indian Ocean. This study is intended to explore any possible relation between the sea surface temperature and precipitation, if any. Results of this study will be contributes to the prediction of monsoon using sea surface temperature. Insitu sea surface temperature, precipitation and wind data, for the period from 2007-12, are collected from the eleven buoys (Bay of Bengal (BoB) -3, Equator (EQ) -2, and south of equator (SoE) - 06), moored under the Array for African-Asian-Australian Monsoon Analysis and Prediction program (RAMA) of the Global Tropical Moored Buoy Array. The buoys are an integral part of the Global Ocean Observing System (GOOS) and Global and Climate Observing System (GCOS). Linear correlations were obtained between SST and precipitation in the same region as well as different regions. No any significant correlation was observed between SST and precipitation in the equatorial region and BoB, but significant positive correlation (0.58) was shown in the south of equatorial region. There were significant negative correlations have shown between SST and precipitation in the equator and the south of the equator (0.73), BOB and the south of the equator (0.78), south of the equator and BoB (0.75) respectively. It was found that the rainfall in the south of equator is affected by SST during the northeast monsoon, but rainfall in the north of equator affected by SST during southwest monsoon. Therefore, it can be concluded that the SST has a negative relationship with southwest monsoon in north of equator and northeast monsoon in the south of equator. Key words: Precipitation, RAMA buoy, Sea surface temperature,
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    ASSESSMENT OF MICROBIOLOGICAL QUALITY OF WATER IN SEA BATHING SITES IN THE WEST COAST OF SRI LANKA
    (Uva Wellassa University of Sri Lanka, 2014) BANDARA, A.M.T.
    Globally, there is a growing interest in investigating microbiological water quality (WQ) in sea bathing sites due to the increasing coastal pollution. This is more important for islands such as Sri Lanka, since coastal pollution has considerable socio-economic implications. Therefore, this study was conducted to assess the current status of the WQ in two sea bathing sites; Mount Lavinia (ML), Moragalla (MR) and a reference site in Kalutara district of Sri Lanka. Since ML (Colombo district) and MR (Kalutara district) are two popular sea bathing sites among tourist, these sites were selected for the study. Further, non-bathing site in Kalutara district was selected as the reference site. Weekly changes of WQ parameters of the selected sites were recorded for three months and microbiological tests were performed to detect fecal coliforms (FC) and fecal streptococci (FS) in each sample separately. The comparison of WQ parameters in all three sites during the experimental period was conducted by ANOVA using Minitab 16 software. Sanitary inspection was conducted in both sea bathing sites to identify the potential sources of fecal contamination and finally beach suitability grades (BSG) were determined by combining categories obtained from sanitary inspection and microbial assessment. Results showed that temperature, dissolved oxygen and pH were in-' standard range for healthy sea bathing sites whereas other physio-chemical WQ parameters including salinity, conductivity, turbidity and total dissolved solids were below the standard range throughout the experimental period. A significant different was observed in temperature, salinity, total dissolved solids and electrical conductivity among three experimental sites (P<0.05). Further, ML has reported significantly higher FC count compared to the reference site (P<0.05). Based on the FC count, BSG fOr both ML and MR Sea bathing sites were determined as 'very high'. However, based on FS count, the BSG for ML and MR were 'poor' and 'fair' respectively. Hence, it is recommended to develop and implement strategies including environmental education, WQ monitoring procedures and beach management to create healthy sea bathing sites in Sri Lanka.
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    Assessment of Physicochemical and Sensory Parameters of Ready to Use Jelly Developed by Using Kappaphycus alvarezii
    (Uva Wellassa University of Sri Lanka, 2016) Rathnasiri, O.A.D.N.
    In Sri Lanka, the industry of processing cultured seaweeds for the regular consumer market in the form of food products is in its preliminary stage. However, with the increasing awareness surrounding consumption of healthier food, a gap is being created in the consumer market for nutrient rich seaweed based products. This study was aimed to develop a new seaweed based jelly which would be promoted as a nutrient dense snack. Kappaphycus alvarezii is a variety of marine macro red algae which are high in nutritional value due to the favorable climatic conditions and Kappaphycus alvearezii is the most commercially available and harvestable seaweed in Sri Lanka. Seaweed samples (Kappaphycus alvearezii) collected from valeipadu farm in Killinochchi, Sri Lanka. To identify the composition of raw materials and ingredients for the development of the jelly product, preliminary trials were conducted. Passion fruit (Passiflora incarnate) was used as a flavor enhancer and to mask the odor. Sensory analyses were conducted using three concentrations of passion fruit juice (10, 15, and 20%) mix with cinnamon powder (0.25%) and sugar (25%). Final products were cooled at 3 °C for 1 hour and stored in a refrigerator. The selected final product was analyzed for organoleptic parameters, proximate composition and maintaining quality characters. The results of this research indicate that the incorporation of passion fruit 20% with seaweed powder 4% allows the most effect on protein content (8.54), fat content (0.53), fiber content (16.65), ash content (35.21), of proximate analysis and acidity (3.03). A sensory evaluation was conducted on the appearance, color, aroma, taste, texture and overall acceptability of the product. According to physicochemical assessment and microbiological tests, this product was safer for consumption within 4 weeks of production. In conclusion, this seaweed-based jelly product can be introduced as a healthy, fully natural good alternative to diary based yoghurt, especially in the growing vegan market. Keywords: Nutritious jelly; Kappaphycus alvearezii; physicochemical properties; Seaweed based product
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    ASSESSMENT OF THE CURRENT STATUS OF WATER QUALITY AND POLLUTION LEVELS IN HIKKADUWA, GALLE AND HAMBANTHOTA FISHERY HARBOURS, SRI LANKA: ACOMPARATIVE STUDY
    (Uva Wellassa University of Sri Lanka, 2014) JAYAMPATHI, O.M.M.D.
    Fishery harbour in Sri Lanka has been polluting in many aspects from the recent past due to irregular monitoring of pollutants. This study was carried out with the objective of assessing the water quality and severity of the pollution level in three selected fishery harbours namely Galle, Hambanthota, Hikkaduwa located in the southern coast of Sri Lanka. The study was carried out from May 2014 to July 2014 and sampling was done on monthly basis from three stations from each harbour. Dissolve doxygen, water temperature, pH, turbidity, conductivity, total dissolved solids and salinity were determined in situ using Thermometer, pH meter , turbidity meter, conductivity and collected water samples were subjected to laboratory analysis using standard methods for the Dthmination of Water and Waste Water,(APHA 20th edition). The study identified the main contributors of deterioration of harbour water quality are vessel generated discharges, industrial, domestic waste water,user generated pollutants and external sources as natural phenomenon. pH ,DO , Salinity ,Nitrate - N ,Nitrite — N ,EC were within the acceptable standards in each harbour. Harbour water was characterized significantly high Biological Oxygen Demand (9.67 ± 0.7mg1-1) (7.1 + 0.43mg1-1)(9.17 0.25mg1-1) respectively and high Chemical Oxygen Demand (719.51 ± 161.63 mgl-1),(926. 5 ± 93.5 mgl-1), 840.2 ± 104.8 mgl-1).high oil and grease content(13.1 ± 0.6 mgl-1),(17.9 ± 0.2 mgl-1),(17.8 ± 1.2 mgl-1)in Hikkaduwa, Galle, Hambanthota respectively exceed the recommended level. MPN value of fecal coliforms 2400 /100 cfu/ml, which exceeded the recommended standards in Galle and Hambanthota and Hikkaduwa has 1600/100 cfu/ml. Diatoms and copepods were dominant in plankton studies of each harbour. Results of this study revealed that the harbour has been degraded in many aspects and harbour is subjected to severe oil pollution, organic pollution and microbial contamination
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    ASSESSMENT OF THE IMPACT OF AQUACULTURE PRACTICES IN THE PUTTALAM LAGOON ON THE MANGROVE ECOSYSTEM BY USING REMOTE SENSING AND GIS TECHNOLOGY
    (Uva Wellassa University of Sri Lanka, 2014) NISANSALA, R.M.H.N.K.
    Mangrove ecosystems dominate the coastal wetlands throughout the world as well as in Sri Lanka. At the same time, mangroves are among one of the most threatened and vulnerable ecosystems. Presently managing and conservation of such resources is a promising need. Thus it is essential to have relevant information regarding the resource condition. The study was conducted having the main objective of observing the mangrove cover changes in Puttalam lagoon over the past seven decades. Recognizing whether there was an impact from the shrimp farming industry for the changes in mangrove coverage was the second objective of the study. Presently remote sensing and GIS technology are significantly applied in coastal resource monitoring and management and for this study also high resolution remotely sensed images were used. Aerial Photographs (for year 1956, 1981, 1992), IKONOS satellite images (for year 2005) and Google Earth images (for year 2014) with a spatial resolution < 1 m were used as the base data sources. Tone, texture, shape and association like visual interpretation keys were used to identify mangroves, shrimp farms and salt pans from the images. For the data extraction on mangroves, salt pans and shrimp farms on screen digitizing was done. Final extent calculations were conducted using ArcGIS software. As to the final results there are 1642.3 ha of mangrove cover presently at the Puttalam lagoon and it is a 1.45 % reduction compared to the extent in 1956. Shrimp farm extent in lagoon has gone up from 21.40 % compared to 1992. Presently it can observe 880.32 ha of abandoned shrimp farm all over the lagoon and number of active farms is very low compared to abandon. Statistically it shows that there was no any significant impact happened to mangrove ecosystems due to shrimp farm establishments in the lagoon. For the sustainable management of mangrove resources it need to restore the abandoned shrimp farm areas with mangrove. For that declare mangrove regenerating abandoned shrimp farm areas as protected areas, community base mangrove restoration projects and conducting community awareness programs is essential. Key words: Mangrove, Remote sensing, Geographic Information System, Shrimp farms, Salt pans
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    AN ASSESSMENT OF THE WATER QUALITY AND POLLUTION LEVEL IN BOMURUELLA RESERVOIR, NUWARAELIYA, DISTRICT
    (Uva Wellassa University of Sri Lanka, 2014) WIJAYASINGHE, T.W.S.H.
    Bomuruella Reservoir which feeds Uma Oya is an important water source in the NuwaraEliya District. The reservoir is surrounded by Kadapola — SeethaEliya Forest Reserve. The Reservoir is used for various purposes such as fishing, agricultural activities, drinking, cleaning and washing purposes by those who live in the surrounding area.. This study was mainly focused to estimate water quality of the reservoir to assess its health and identify the factors that affect on pollution of the reservoir. The mean average values of nitrate, nitrite, phosphate, alkalinity, Ca and, total hardness Biological Oxygen Demand (BOD) and Dissolved oxygen (DO) concentration in Bomuruella Reservoir were 0.0910.58 mg/L, 0.0810.26 mg/L,0.00710.69 mg/L,37.5±131.93 mg/L,10.42±9.49 mg/L,38±0.51 mg/L, 3.413.71 mg/L and 6.25±1.62 mg/L3.4±3.71 mg/L and 6.2511.62 mg/L respectively. According to the results most sample points which is located in near to the land treatment leachate and agricultural area did not satisfy the specified standards of Central Environmental Authority, Sri Lanka. This concludes that the reservoir was contaminated with high loads of organic waste. Furthermore, the effluent from the land treatment area has recorded higher levels of conductivity, nitrate, Chemical Oxygen Demand, ammonia while recording low values for BOD and DO which indicating the impact of land fill treatment water to the reservoir .The main cause of pollution of the reservoir is the discharge of agricultural runoff, industrial and hospital waste directly into the reservoir, raw sewage and domestic wastes. It can be recommended that standard limit for discharge of effluents into surface waters should be followed when discharging effluents into water bodies and there should be proper monitoring mechanism.
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    BIO ASSAY ON EFFECTIVENESS OF CHEMICAL HYDROLIZATION FOR DENATURING AGROCHEMICAL CONTAMINATED WASTEWATER
    (Uva Wellassa University of Sri Lanka, 2014) WICKRAMA, G.M.G.M.M.
    Pesticides provide the primary means for controlling organisms that compete with man for food and fiber, livestock and crops. Pesticides cause direct and indirect effects to the ecosystems and for animals.There are several treatment methods are available to detoxify agrochemical residuals, as chemical, physical and biochemical methods. Present study has focused to analyze the effectiveness of chemical hydrolysis for denaturing agrochemical contaminated wastewater and to investigate the effect of treated wastewater by "Alkaline Hydrolysis" to the aquatic organisms using Poecilia reticulata. Effectiveness was analyzed by comparing the COD and pesticide analysis before and after the hydrolysis treatment to the agrochemical contaminated water and acute toxicity of Profenofos was investigated by using guppy (P.reticulata). Behaviors and mortality rates were evaluated 'after introducing them to the treated effluent. One hundred fifty specimens of P. reticulate with mean length 2.5 cm and mean weight 0.2 g.Physico-chemical parameters such as DO,Temperature, pH of the test media were maintained during the experiment period. Mortality assessment was carried out for 24h to 96h of experimental period. Fishes were assumed to be dead when there was no body or opercula movement. All the data were analyzed statistically using one way ANOVA (analysis of variance). No adverse behavioral changes or any mortality was recorded in the control fish tanks throughout the period of bio assay. Symptoms of toxicosis observed in the behavioral of fish exposed to test media. Before the eventual death species showed lack of balance erratic swimming and restlessness. In the study highest mortality was recorded, in less diluted effluent and lowest exposure time (24 h) ,lowest mortality was recorded in highest dilution(75%) and longest exposure time(96 h). And further ,the study was revealed that when comparing the COD, and pesticide analysis before and after the treatment, it has the ability to reduce those chemical parameters in high efficiency and convert pesticide active ingredient in to non detectable level. findings in this study has proved that when discharging the agrochemical contaminated waste water after hydrolyzation, it should be mixed with rain or storm water and keep the contaminated water in the maturation tank for further degradation. Because in the study it has shown highest dilution and highest exposure duration caused minimum mortality.
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    BIOACCUMULATION OF CADMIUM (Cd) AND MERCURY (Hg) IN TILAPIA (Oreochromis niloticus) FISH MUSCLES FROM THREE MAIN RESERVOIRS IN BADULLA DISTRICT; IMPLICATIONS ON FOOD SAFETY
    (Uva Wellassa University of Sri Lanka, 2016) SHYAMALI JAYANANDA, K.N.
    Bioaccumulation of toxic trace metals in fish muscle is a major issue in the aquatic environment. The consumption of toxic trace metal contaminated fish cause health risks to human. The objective of the present study was to determine cadmium (Cd) and mercury (Hg) concentrations in muscle tissues of tilapia (Oreochromis niloticus) randomly collected from Sorabora (n = 8), Mapakada (n = 7) and Ulhitiya (n = 9) reservoirs in Badulla District from September to October 2016. The samples were digested by microwave accelerated system and Cd & Hg concentrations in muscle tissues of each fish were determined by Atomic Absorption Spectrophotometry (AAS). The recorded mean concentration of Cd in Sorabora reservoir was 0.024 + 0.026 mg/kg and Hg was not detected, while 0.018 ± 0.005 mg/kg Cd was recorded for Mapakada reservoir and Hg was not detected. The mean concentrations of Cd & Hg in Ulhitiya reservoir were recorded as 0.009 ± 0.001 mg/kg and 0.049 + 0.136 mg/kg, respectively. The mean concentrations of Cd & Hg those were recorded for three reservoirs were lower than the maximum permissible levels of these two toxic trace metals (Cd < 0.05 mg/kg & Hg < 0.5 mg/kg) recommended by the European Union and Sri Lankan guide lines for food fish. The amount of fish that should be consumed to fulfill weekly protein requirement (total amount by eating fish) of a healthy person was calculated according to the guidelines of the World Health Organization. Thereby, the Probable Weekly Intake (PWI) levels of Cd & Hg were calculated (0.00009 and 0.0001 mg/kg of body weight per week, respectively) and those values were well below the Provisional Tolerable Weekly Intake (PTWI) recommended (0.275 for Cd & 0.385 mg/kg of body weight per week for Hg) by the Joint Expert Committee for Food Additives (JECFA -FAO and WHO). The results indicate that the consumption of 0. niloticus fish from studied three reservoirs are generally safe in terms of toxicity risk by Cd & Hg for human health. Key words: Tilapia (Oreochromis niloticus), Cadmium (Cd), Mercury (Hg), Bioaccumulation, Health risk
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