Browsing by Author "Abeygunawardana, A.P."
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Item The Aspects on Reproductive Biology of Blue Swimming Crab Portunus pelagicus, (Linnaeus, 1758) in Mannar Area(Uva Wellassa University of Sri Lanka, 2016) Abeygunawardana, A.P.; Jayamanne, S.C.Blue swimming crab fishery is a newly emerging export oriented fishery in North and North-Eastern provinces of Sri Lanka. Since the exploitation is heavy in these areas establishment of management strategies are important for sustainability of the fisheries. Hence the aspects on reproductive biology such as maturity stages, pre-spawning and post spawning fecundity, size at first maturity and gonadosomatic index of the Blue swimming crab (Portunus pealagicus) in Mannar area were studied during the period, May to July, 2015. The fecundity was estimated using Gravimetric method. Six ovarian development stages, immature, developing, early Mature, late mature, ripe and spent were identified in non ovigerous crabs and five ovarian development stages, light yellow ovaries, pale yellow ovaries, pale orange ovaries, black colour ovaries and grey colour ovaries were identified in ovigerous female crabs. The size at first maturity was determined as 57.5 mm carapace length and carapace width 113.50 mm. The pre spawning fecundity estimates ranged from 105874 to 516000 in the crabs of 133 mm to 158 mm carapace width. The post spawning fecundity estimates ranged from 537600 to 1739000 in the crabs of 121 mm to161 mm carapace width. The pre spawning fecundity and the post spawning fecundity showed positive correlations with the carapace width, carapace length and the body weight (P<0.01). The Gonadosomatic Index of the female crabs varied from 0.94+0.0208 in immature crabs to 30.6 +0.8048 in matured crabs. More than 80 % of the catches contained immature crabs while percentage of ovigerous females was 8%. High exploitation of immature crabs and ovigerous crabs may have serious impacts on the sustainability of the Blue swimming crab fishery in future. Keywords: Carapace length, Pre spawning fecundity, Post spawning fecundity, Reproductive biology.Item Assessment of Macroalgae Diversity along the Economically Important Southern Coastal Zone of Sri Lanka during North East (NE) Monsoon Period(Uva Wellassa University of Sri Lanka, 2020) Wijethunga, H.N.S.; Silva, A.P.R.; Shanuke, D.S.; Abeygunawardana, A.P.; Senevirthna, J.D.M.; Bambaranda, B.V.A.S.M.; Thushari, G.G.N.; Liyanage, N.P.P.Southern coastal zone acts as a highly productive ecosystem with rich macroalgae diversity. However, limited scientific studies have been conducted on macroalgae diversity in the southern coastal belt of Sri Lanka. The current study is focused on the assessment of the intertidal, macroalgae diversity along this coastal belt. This study was conducted using systematic sampling technique along the intertidal zone at 12 selected regional coasts (Hambantota, Godawaya, Rekawa, Tangalle, Dickwella, Polhena, Mirissa, Weligama, Unawatuna, Galle Fort, Dodanduwa and Hikkaduwa) representing three districts (Hambantota, Matara, Galle) of the southern province during NE monsoon period (December 2019 to February 2020). NE monsoon period was selected to minimize the climatic effects during sampling in different seasons. Macroalgae species were taxonomically identified using the recommended pictorial guides and literature records. Oneway Analysis of Variance (ANOVA) was employed to identify the variations of macroalgae diversity with sampling location (p<0.05). According to the results, a total of 26 macroalgae species (10 belong to Chlorophyta: >38% richness, 10 in Rhodophyta: >38% richness, and 6 from Phaeophyta: >23 % richness) were identified in this coastal belt. Ecologically dominant species belong to division Chlorophyta out of all the sampling sites. Shannon-Wiener biodiversity index (H') of the macroalgae in respective ecosystems significantly changed with sampling locations (p<0.05). The spatial variation pattern of biodiversity is correlated with unsustainable anthropogenic activities and natural factors. Shannon-Wiener biodiversity index (H') ranged at 0.67-2.59 in the study sites. The highest composition of macroalgal species (20) was recorded from the Godawaya site due to the minimum anthropogenic effect. Mirissa (02) and Dodanduwa (01) regions had the lowest macroalgae species richness and commercial activities were relatively higher along these coastal zones compared to all other sites. Accordingly, macroalgae act as the biological indicators reflecting the health status of respective ecosystems. So, the findings of this study would be important to identify the quality of the coastal zones and apply appropriate coastal conservation and management measures in the future. Also, the commonly recorded macroalgae species which belong to Chlorophyta and Rhodophyta can be sustainably utilized in processing value-added foods and other products. In conclusion, this study reveals the current status of macroalgae diversity on the southern coast during the NE monsoon period and detailed investigation of species composition is strongly recommended throughout the year. Keywords: Biodiversity assessment, North east monsoon, Macroalgae, Intertidal zone, Coastal ecosystemsItem Assessment of Suspended Plastic Levels in Surface Water of Southern Coastal Belt in Sri Lanka(Uva Wellassa University of Sri Lanka, 2019-02) Athapaththu, A.M.A.I.K.; Athawuda, A.M.G.A.D.; Dias, P.C.B.; Abeygunawardana, A.P.; Senevirathna, J.D.M.; Thushari, G.G.N.; Liyanage, N.P.P.; Jayamanne, S.C.Plastic pollution is a growing concern all over the world including Sri Lanka due to serious negative consequences. Thus, current study focused on investigation of occurrence, quantification and spatial distribution of visually observed plastics and microplastics (MPs) in surface coastal water from 12 locations (Hikkaduwa, Gallefort, Dodanduwa, Unawatuna, Weligama, Mirissa, Dickwella, Tangalle, Polhena, Rekawa, Godawaya, Hambantota) as covering 3 districts of southern coastal zone in Sri Lanka during July-December 2018. Surface water samples were collected by towing neuston, manta net (380 µm) along surface layer parallel to the shoreline using repeated measures approach. The samples were passed through 4000 µm, 500 µm and 250 µm mesh sieves and residual MPs were subjected to Wet Peroxide Oxidation protocol. Visually observed plastics and recovered MPs were observed through Trinocular Microscope, enumerated for density and confirmed by hot needle test. MPs were further sorted according to the color and shape. As results revealed, all the coastal water in sampling sites were contaminated with plastic accumulation. Overall average density of macroplastics and mesoplastics were recorded as 3.32 and 3.37 items/m³. Sampling location had no significant effect (p>0.05) on total MPs density (average total MPs density: 18.06±11.45 items/m³). Plastic accumulation sources of the affected sites were identified as harbor operational activities, residential actions and recreational events. MP debris with 0.512.00 mm consists of >65% of total number of MPs, whereas maximum size of microscopic plastic in coastal water was 11.04 mm. Fibers were the most common MPs followed by films. Blue colored and Transparent MPs were the majority of plastic items in coastal water due to prevalence of above plastic categories used in the packaging, bottles and fishing gears. In summary, southern coastal water in Sri Lanka is polluted by plastic debris and pollution control programmes are recommended by this study.Item Current Status of Coastal Debris Accumulation along Beach Ecosystems in Southern Province of Sri Lanka(Uva Wellassa University of Sri Lanka, 2020) Athapaththu, A.M.A.I.K.; Egodauyana, K.P.U.T.; Jayarathna, W.N.D.S.; Abeygunawardana, A.P.; Senevirathna, J.D.M.; Thushari, G.G.N.Coastal debris accumulation in coastal and marine ecosystems is considered one of the serious, the emerging environmental problem in several countries including Sri Lanka. This study aims to identify the current status of debris accumulation in the coastal zone of Southern province in Sri Lanka. The 180 stakeholders were interviewed to collect data using a pre-tested questionnaire survey through 15 open-ended and rank order closedended questions (maximum 1-10 of scale) as a convenience sampling method. Based on the estimated median rank data, the majority of waste types were plastic (991.5), followed by glass (819.5) and papers (768.5) in the Southern coastal zone. Soft drink/water bottles (1264) were recorded as the major disposal items followed by food wrappings (1225) and Styrofoam food containers (1146) considering rank scores. Burning or collecting wastes (32.09%), handing over the garbage to the municipal council (25.5%), usage of public garbage bins (25.11%) are common waste disposal methods along the southern coast. The highest percentage of waste separation practices were recorded from Hikkaduwa (81.81%), Galle fort (60%), and Polhena (61.11%) regions. Hambantota and Tangalle beaches have regular waste collection services (100%) to a satisfactory level. Rekawa and Godawaya regional coasts had not recorded any frequent waste collection mechanism. Tourism and recreational activities (86.36-52.94%) and fisheries and harbor operations (93.33-60%) are major waste accumulation sources in study sites. Coastal debris is also accumulated by residential and household activities and unsustainable constructions to a lesser extent. Thus, unsustainable anthropogenic activities are major sources of coastal debris accumulation. The majority of fishermen and coastal residents did not adequately aware of the ecological and commercial impacts of coastal debris. This study suggests implementing integrated coastal management programs focusing on plastic debris accumulating sources. In conclusion, this study provides a basic platform on the issue of coastal debris deposition on the southern coast of Sri Lanka. Keywords: Plastic pollution, Coastal debris accumulation, Coastal environment, Pollution sources, Anthropogenic activitiesItem Development of Fish Balls Using Catla Fish (Catla catla): Exploration the Potential of Better Utilization of Freshwater Food Fish in Sri Lanka(Uva Wellassa University of Sri Lanka, 2019) Leshika, D. L.; Athawuda, A.M.G.A. D.; Abeygunawardana, A.P.; Thushari, G.G.N.; Jayamanne, S.C.Catla fish is the one of mostly cultivated, freshwater food fish in aquaculture sector. Present study was aimed to enhance Carp fish production by developing a value added fish ball products from Catla using appropriate processing technologies. Catla fish were collected from Ulhitiya reservoir. Three different treatments of fish meat:ice water ratios (w/v) as: 50%:37% (treatment1), 70%:17% (treatment2) and 85%:2% (treatment3) were used for fish ball processing after the preliminary trials. Organoleptic evaluation was conducted to determine color, texture, aroma, mouth feel, taste and overall acceptance of products using 30 untrained panelists. pH, color, and TBARS values of all final products at -20°C freezing condition were measured weekly. The proximate compositions of fish ball products were analyzed following standard protocols. Based on the results, highest scores for aroma, taste and overall acceptance were recorded for treatment 2 (fish meat: ice water-70%:17%). Ash content of treatment 1, 2 and 3 were 4.06±0.4%, 4.27±0.92% and 4.00±0.82% respectively with no significant difference (P>0.05). However, moisture and lipid contents had significant difference (P<0.05) among the treatments, while the highest lipid content was recorded in treatment1 (6.96±0.60%) and the lowest moisture content was recorded in treatment2 (70.15±2.43%). Protein content of Catla fish ball products varied from 14.00 to 15.00%. TBARS and pH of all treatments were at the range of 6.41-6.51 and 0.36-0.90 mg MDA/kg respectively which were within acceptable levels for consumption during storage. L*, a* and b*values of final products gradually decreased during storage period, but without significant (P>0.05) variation during storage period. In conclusion, Catla is a suitable alternative source for production of high quality, consumer preferred fish balls.Item Development of Seaweed Based Ready-to-Serve (RTS) Beverage using Elkhorn Sea Moss: Kappaphycus alvarezii - A Novel Approach in Value Addition to Seaweed Resources in Sri Lanka(Uva Wellassa University of Sri Lanka, 2020) Karunarathne, K.M.C.S.; Kulasinghe, W.M.A.A.; Thushari, G.G.N.; Abeygunawardana, A.P.; Silva, A.P.R.; Jayarathne, D.S.W.N.; Liyanage, N.P.P.In Sri Lanka, the development of seaweed-based food products such as nutritious drinks still gained less attention. This study was focused on the identification of product processing potential with appropriate production technology for the RTS beverage using common red algae: Kappaphycus alvarezii having high culture potential in Sri Lanka. Preliminary trials were conducted to identify the composition of raw materials and ingredients for the development of RTS products. Then, final experiments were followed using 3 levels of Kappaphycus extracts (15, 20, and 25%) blended with 5% fresh lime juice. Final products were subjected to pasteurization at 90 ºC for 5 min and stored at room temperature. The selected final product was analyzed for organoleptic parameters, proximate composition, and keeping quality characters. Results indicated the production potential of value-added RTS beverage using red algae. Final treatment with 20% of K. alverazii recorded as the best product with the highest consumer preference. Based on the results, this RTS beverage contained a significant amount of minerals (2.05±0.01%) and high antioxidant potential (~70%) with 0.001% of carbohydrate level closer to zero (atkins drink) compared to the market available products. pH level (4.37±0.06 - 3.90±0.05), antioxidant property (70.98±1.7 - 53.3±2.0%), acidity (0.30 - 0.36%) and Total Plate Count (2.60 - 3.60 log CFU ml-1 ) of final product had a significant effect with storage time period (P <0.05). Total Soluble Solid level of the product (1.2 ºBrix) was constant during the storage period due to extremely low sugar content. According to physicochemical parameters and microbiological tests, this product was safer for consumption within 4 weeks of the period. Moreover, the production cost is relatively lower compared to the market available, common beverage products. In conclusion, this seaweed-based product can be introduced as a healthy, low-cost, atkins drink as an alternative to conventional beverages. Keywords: Nutritious beverage, Red algae, Atkins drink, Physico-chemical properties, Seaweed based productItem Diversity of Mangrove Associated Brachyuran Fauna in Panama Lagoon, Eastern Coastal of Sri Lanka(Uva Wellassa University of Sri Lanka, 2020) De Silva, E.R.K.; Jayamanne, S.C.; Abeygunawardana, A.P.Mangroves are salt-tolerant plant communities that provide unique habitats for a wide range of faunal communities. Panama lagoon is pristine with rich mangrove coverage. The present study was carried out to investigate the diversity of mangrove associated brachyuran fauna in the Panama lagoon, on the East coast of Sri Lanka. Field sampling was conducted in six sampling sites, covering the entire lagoon from November 2019 to January 2020. In each site, three belt transects were laid perpendicular to the lagoon. The belt transects were 10 m to 30 m depending on the length of the mangrove patch. It was subdivided into 10 m×10 m plots and which had six 1 m×1 m randomly selected sampling units. The sampling area was dug into the water level until the crabs were caught and picked by hand. Several crabs from different species were recorded. Crabs were identified up to species level using external morphological characters. Salinity, temperature, and pH of mangrove soil were measured. Seven species of brachyuran crabs belonging to four families were identified up to the species level. They were Parasesarma plicatum, Metopograpsus thukuhar, Metasesarma obesum, Episesarma mederi, Episesarma versicolor, Cardisoma armatum, and Varuna litterata. The Parasesarma plicatum was recorded as the most dominant species due to it was recorded in whole sites of the lagoon. The lower and middle areas of the lagoon recorded 1.51 and 1.13 for the Shannon wiener indexes and no species found in the upper area of the lagoon. The distribution pattern of dominant species up to 10 m, 20 m, 30m level. The salinity showed a negative correlation (p < 0.01) with the increasing distance from the lagoon. The distribution of Cardisoma armatum showed a positive correlation (p< 0.01) with the soil salinity. Panama lagoon consists of rich brachyuran fauna diversity and it plays a virtual role in the ecological process and must be conserved for the future generation. Keywords: Brachyuran crabs, Fauna, Mangrove, Panama lagoon, Shannon wiener indexesItem Diversity, Stand Density and Structure of Mangroves in Panama Lagoon, Sri Lanka(Uva Wellassa University of Sri Lanka, 2020) Pathmasekara, K.G.; Jayamanne, S.C.; Abeygunawardana, A.P.This study was undertaken to estimate the diversity, stand density, and structure of mangrove flora in Panama lagoon which has identified as a location with rich mangrove vegetation in Ampara district, Sri Lanka. Six sites covering the whole lagoon were assessed using the transect line plots method by laying three transect lines perpendicular to the shoreline at each site which was varying from 10 m to 40 m in length. The number of mangrove species with the distance from the shore including their diameter (cm) and height (m) were recorded. The individuals were categorized as trees, saplings, and seedlings based on their diameter. The in-situ parameters of soil pH, temperature, and salinity were measured. Five true mangrove species belong to families of Avicenniaceae (Avicennia marina), Rhizophoraceae (Rhizophora mucronata, and Bruguiera sexangula), Combretaceae (Lumnitzera racemosa) and Euphorbiaceae (Excoecaria agallocha) were recorded. Avicennia marina was the most dominant species with the Importance Value of 68.65. The stand density of 475 individuals/ha represented 56% of tree density, 19% of sapling density, and 25% of seedling density. The greatest Shannon-Weiner diversity (1.79) was recorded in site 03 while site 06 recorded the highest Simpson’s Diversity Index (0.83) and Pielou’s Evenness Index (0.98). Site 05 obtained the highest Margalef’s Species Richness (1.83). Highest Basal Area of 70.28m²/ha in site 01 confirmed the undisturbed nature of mangroves. There was a negative linear relationship between distance from the shore and average salinity (p<0.05) and a positive linear relationship between salinity and mangrove abundance (p<0.05). The cluster analysis depicted the highest similarity of 90.81 for site 03 and 06 based on diversity. Lumnitzera racemosa and Excoecaria agallocha showed the highest similarity (84.14) based on dominance and density. The results indicated the pristine nature of Panama lagoon with high biological diversity of mangrove flora. Keywords: Panama lagoon, Mangrove flora, Dominance, Stand basal areaItem Fishery Independent Assessment of the Size on Maturity of the Palk Bay Blue Swimming Crab Fishery (Portunus pelagicus) in Jaffna District(Uva Wellassa University of Sri Lanka, 2018) Manivannan, M.; Abeygunawardana, A.P.; Creech, S.; Jayamanne, S.C.Blue swimming crab (Portunus pelagicus) fishery industry in Sri Lanka has become a valuable source of foreign exchange recently, developed following the end of civil conflict in 2009. Size on maturity is a key life history parameter of exploited populations, used in fishery management practices. The aim of this study was to investigate the size on maturity of Portunus pelagicus by using a standardized sampling approach for the Palk Bay fishery. Crab samples were collected from both stake net fishery and crab net fishery during September-November, 2017. Portunus pelagicus were sampled from bottom-set crab nets in Mandaitheevu, Thuraiyoor and Chattipulam. Portunus pelagicus caught in stake nets were sampled from Kurunagar and Pannai. The maturity for standard sample of female crabs were assessed for a series of length classes ranged at 40 inm-159 mm, to identify the size on maturity for Portunus pelagicus in Jaffna District in the Palk Bay fishery. 1,253 of total female crabs were sampled. Carapace width and weight of Portunus pelagicus were recorded and Excel solver was used to estimate the size on maturity. The results of size on maturity data collected from crab net fishery dependent data were then compared. The level of maturity and immaturity for crab net were 83% and 17% respectively. 10% and 90% maturity and immaturity level were recorded for stake net fishery. As results revealed, L50 was recorded as 110.41 mm and L95 was 130.87 mm for this stock. According to the results and dependent data analysis, there is an effect in size on maturity of Portunus pelagicus by different sampling approaches in Palk Bay Fishery.Item Occurrence of Microplastics in Gut and Muscles of Commerson's Anchovy in Madu-Ganga Estuary of Southern Province, Sri Lanka(Uva Wellassa University of Sri Lanka, 2020) Praboda, M.W.K.; Egodauyana, K.P.U.T.; Wijethunga, H.N.S.; Abeygunawardana, A.P.; Senevirathna, J.D.M.; Thushari, G.G.N.Plastic pollution causes serious ecological risks on biodiversity with toxicological effects on the biota. The objective of this study was to assess microplastic accumulation in seasonally common fishery resource: Stolephorus commersonnii (Commerson's Anchovy) harvested from Madu-ganga estuarine ecosystem. Fifteen matured fish samples (n=15) were randomly collected from local fishermen from November 2019 to January 2020. Microplastic particles were extracted from the digestive tract and muscles of anchovies using the recommended protocol of 10% KOH digestion. Hot needle test and Fourier Transform Infrared Radiation (FTIR) analysis were used for the confirmation of microscopically observed microplastics in anchovy samples. Microscopically observed microplastics were counted and categorized according to the size, color, and shape of plastics. Results revealed the microplastic accumulation in both the digestive tract and muscles of anchovies. Microplastics accumulate into the muscles via translocation and different respiratory modes. The average microplastic accumulation rate of anchovy gut and muscles were recorded as 301.70±3.58 items/g and 29.33±1.19 items/g respectively. White/transparent microplastic particles were the most abundant type in both guts (145.50±2.18 items/g) and muscles (13.55±1.23 items/g) of fish. However, blue (71.33+0.83 items/g: gut, 9.85+1.13 items/g: muscle), black (37.85+1.07 items/g: gut, 2.49+0.44 items/g: muscle), red (28.31+0.60 items/g: gut, 2.31+0.3 items/g: muscle) and pink (15.31+0.34 items/g: gut 0.96+0.24 items/g: muscle) microplastic debris were also recorded from gut and muscle samples. The majority of accumulated plastics in both gut and muscles were at the size range of 0.50 -1.00 mm. Fiber shape microplastics were observed in all the samples. FTIR results revealed that polypropylene as the only polymer type of microplastics in fish muscles and gut. This polymer is a key component of fishing ropes, netting materials, bottle caps, and packaging materials that enter through tourism/recreational activities and fishery operations into the estuarine ecosystem. Therefore, the current study recommends sustainable, integrated fishery management and eco-tourism programs focusing on plastic pollution control and prevention activities in Madu-ganga estuarine ecosystem. In conclusion, this study highlights the occurrence of microplastic contamination in the estuarine biota and the urgent need for plastic wastes management programs. Keywords: Coastal fishery resources, Estuarine ecosystem, Integrated fishery management, Microplastic accumulation rate, Plastic pollution control programmesItem Phytoplankton Diversity in Six Major Reservoirs of Badulla District, Uva Province, Sri Lanka(Uva Wellassa University of Sri Lanka, 2020) Eheliyagoda, P.G.R.; Kumarage, N.T.; Abeygunawardana, A.P.; Thushari, G.G.N.; Liyanage, N.P.P.; Chandrasena, G.; Silva, A.P.R; Wijethunga, H.N.S.Phytoplanktons are major primary producers and act as a bioindicator in inland waters. The present study investigated the phytoplankton species composition of six reservoirs (Ulhitiya, Rathkinda, Mapakada, Nagadeepa, Dambarawa, and Sorabora) with highest inland fish production in Badulla district. Samples were collected using a plankton net (60 μm mesh size) from five sampling points of each reservoir during November 2019- January 2020. The taxonomical status of collected samples was identified using previous literature records, standard pictorial guides (The Genera of the Freshwater Algae of Sri Lanka). Biodiversity indices were calculated to identify the variations of phytoplankton diversity among sampling points and reservoirs. Total of 41 phytoplankton species belonging nine major taxonomic classes; Bacillariophyceae (10), Chlorophyceae (10), Cyanophyceae (08), Zygnemaphyceae (06), Eugenophyceae (02), Fragilariophyceae (02), Chryotophyceae (01), Xanthophyceae (01), Dinophyceae (01) were recorded. Diatoms (Bascillariophyceae) recorded the highest relative abundance (61.57%) from selected reservoirs. Sampling points of each reservoir had no significant effect (p>0.05) on the phytoplankton diversity while it showed a significant effect (p>0.05) on phytoplankton diversity among reservoirs. The highest Shannon-Wiener index (1.61±0.06), Simpson’s Index (0.71±0.01), evenness (0.52±0.024) and richness (21±1.62) were reported from Dambarawa, while lowest Shannon-wiener index (1.25±0.19), Simpson’s index (0.59±0.08), evenness (0.42±0.19) and richness (19±0.89) resulted for Ulhitiya Reservoir. The current study reveals that Aulacoseira sp, Microcystis sp, Pediastrum sp, Staurastrum sp, Arthrospira sp shows the highest abundance in all six reservoirs. Dominant species play a vital role as primary producers, bioindicators (Aulacoseira sp, Microcystis sp), and feed (Staurastrum sp, Arthrospira sp) for fish. Due to the high abundance of Microsystis sp. (51.58%) in the Ulhitiya reservoir, the potential to generate toxic algal blooms was identified by the current study. In conclusion, this study identified the dynamic phytoplankton community and dominant species which act as the major autotrophs in studied reservoirs. Further, data collected could be used as the baseline information for the aquatic ecological studies and inland fishery enhancement programs Keywords: Shannon-Wiener index, Simpson’s index, Biodiversity, Inland fishery, Primary producers/autotrophsItem Screening of Plastic Pollution Effects in Madu-ganga Estuarine Ecosystem in Southern Province, Sri Lanka: An Approach toward the Coastal Zone Management(Uva Wellassa University of Sri Lanka, 2020) Praboda, M.W.K.; Wijethunga, H.N.S.; Silva, A.P.R.; Gayathry, D. L.; Abeygunawardana, A.P.; Senevirathna, J.D.M.; Thushari, G.G.N.Plastic pollutants act as the emerging contaminant with possible threats to aquatic ecosystems. The present study attempts to assess microplastic (MP) content in surface water and sediments of Madu-Ganga estuary which is one of the ecologically and commercially important Ramsar wetlands in Sri Lanka. Manta net (380 μm) was employed to collect surface water samples by towing net horizontally along water surface for 10 m with 1.8 ms-1 of average flow rate, while Ekman grab was used for sampling sediments from 4 study sites during October 2019 to January 2020. Wet Peroxide Oxidation (WPO) protocol was applied after subjecting both water and sediment samples to the wet sieving process. Fourier Transform Infrared Radiation (FTIR) analysis was used to confirm polymer types of extracted MPs in samples. MPs in digested samples were enumerated and categorized microscopically according to their size, shape, and color. One Way Analysis of Variance (ANOVA) was applied to identify the differences of MPs density with sampling location (p<0.05). According to the results, both surface water and sediment layers had contaminated by MPs accumulation. Sampling location had not significant (p>0.05) effect on the MP content of surface water and sediment samples. Average MPs accumulation rate of surface water and sediment samples were recorded as 40.06±1.84 items/m3 and 5.88±1.33 items/100g respectively. Whitetransparent, blue, black, and red were major color categories observed in MPs, while white-transparent color was dominant MP type of water and sediment samples. Most of the accumulated MPs were at the 0.50-1.00 mm of long-range. Fiber, sheet, and fragment shape MPs were commonly found in water and sediment samples. According to FTIR analysis, polypropylene (Characteristic absorption bands: 2950 cm−1 , 2915 cm− 1 , 2838 cm− 1 , 1455 cm− 1 , 1377 cm− 1 ) was abundant polymer type in surface water, while sediment contains polypropylene and polyvinyl chloride (Characteristic absorption bands: 1427 cm−1 , 1331 cm−1 , 1255 cm−1 ,1099 cm−1 , 966 cm−1 ). As per the preliminary survey, two major anthropogenic activities: commercial fishery and tourism were identified as the main point and non-point pollution sources in this ecosystem. In conclusion, this study emphasizes the growing risk of plastic pollution and the urgent need for a sustainable management plan to reduce plastic pollution in the Madu-Ganga estuary ecosystem. Keywords: Plastic contamination, Microplastics, Coastal ecosystem, Surface water, Benthic sediments, Anthropogenic factorsItem Screening the Effects of Microplastics on Selected Invertebrates along Southern Coastal Belt in Sri Lanka: A Preliminary Approach to Coastal Pollution Control(Uva Wellassa University of Sri Lanka, 2019-02) Wijethunga, H.N.S.; Athawuda, A.M.G.A.D; Dias, P.C.B; Abeygunawardana, A.P.; Senevirathna, J.D.M.; Thushari, G.G.N.; Liyanage, N.P.P.; Jayamanne, S.C.Primary and secondary microplastics entering into coastal and marine environment are potentially harmful to the health of aquatic organisms. Current study intended to assess plastic pollution effects on sessile invertebrates along the Southern coastal belt of Sri Lanka during July-December 2018. Twelve sampling sites (Hambantota, Godawaya, Rekawa, Tangalle, Dickwella, Polhena, Mirissa, Weligama, Unawatuna, Gallefort, Dodanduwa and Hikkaduwa) with different anthropogenic activities were selected as representing 03 districts (Hambantota, Matara, Galle) of Southern province. Biodiversity survey was conducted to identify prevalence of natural inhabitants in selected regional coasts and 03 dominant coastal mollusks: Saccostrea cucullata (Rock Oyster), Littorina sp. (Periwinkle) and Patella sp. (Limpets) were selected for screening microplastics accumulation level. Alkaline digestion protocol was identified as the most suitable procedure for microplastics extraction considering plastics recovery rate and digestion efficiency of flesh. Randomly collected, pooled biological samples (N=20-2) were subjected to KOH digestion and resultant microplastics were verified using hot needle test. As results revealed, all 03 invertebrates were contaminated with microplastics accumulation at average rates of 7.2-2.8counts/g in all sampling sites. Majority of contaminated microplastics were filamentous types (>90%) followed by rod shapes (1%). Microplastic accumulation rate varied significantly according to the type of species (p<0.05) due to differences of their feeding mechanism. Further, filter feeding organisms (Rock Oysters) were highly susceptible in accumulation of microplastics (7.24.1counts/g) in their bodies, while plastic accumulation rate was highest in oysters from Hambantota. Microplastic accumulation rate of mollusks was not significantly different according to the sampling site due to closer proximity (p>0.05). Tourism, unsustainable coastal fishery and harbor operational activities were identified as key factors affecting on higher plastic pollution level on Southern coast. Current study reflects negative aspect of plastic pollution on intertidal organisms.Item Shoreline Changes along the Western and North-Western Coast of Sri Lanka over the Past 15 Years(Uva Wellassa University of Sri Lanka, 2020) Abeykoon, K.W.H.M.R.L.C.K.; Thilakarathne, E.P.D.N.; Abeygunawardana, A.P.; Egodauyana, K.P.U.TCoastal Zone of a country is a very important interface, through which land connects the ocean. Monitoring the coastal zone of Sri Lanka is an important task in terms of sustainable development and environmental protection. As a result of natural phenomena and anthropogenic activities coastal zone is subjected to major changes. Therefore, it is necessary to identify the temporal dynamics of shoreline around the country for effective coastal zone management. Remote sensing and GIS methods can be efficiently used to determine the temporal and spatial variations of the coastal zones quantitatively and qualitatively. In this study, Google Earth satellite images have been used to analyse shoreline changes in the Western and North-Western provincial coast during the last 15 years. To estimate the accuracy of results, the ground-truthing field survey was conducted. The shorelines were delineated in Google Earth Pro 7.3 software. Tidal variation and geometric errors were considered to calculate the uncertainty to eliminate the errors in the analysis. Digital Shoreline Analysis System in ArcGIS was then used to detect the shoreline change over the period by calculating End Point Rate, Net Shoreline Movement and Shoreline Change Envelope means as the key statistics. The results show that the average erosion rates as; -1.21±0.04 m yr-1 in Kaluthara, -0.54±0.63 m yr -1 in Colombo, and -0.7±0.58 m yr-1 in Gampaha districts. However, Puttalam district shows a 0.26±0.07 m yr-1 average accretion rate while the highest accretion rate 0.95±0.58 m yr-1 shows in the Wilpattu region. 75.6% of coasts in Kaluthara and around 65% of coasts in Colombo & Gampaha have been subjected to erosion. Coasts of Puttalam have been eroded by 28.1% and accreted by 71.9%. This study revealed that the Western province coastal belt had subjected to coastal erosion than the North-Western province of Sri Lanka. Thus, identification of the dynamic nature of shoreline helps to enhance coastal zone management. Keywords: Shoreline, Remote sensing, Dynamic, Erosion, Coastal changesItem Some Aspects of the Reproductive Biology of Dasyatis zugei (Paleedged stingray) in the Gulf of Mannar, Sri Lanka(Uva Wellassa University of Sri Lanka, 2019-02) Gayathry, L.D.; Abeygunawardana, A.P.; Jayawardana, J.M.D.R.; Jayamanne, S.C.Dasyatis zugei is one of the major non-target species caught in the bottom-set crab nets used for catching blue swimming crab (Portunus pelagicus) in Gulf of Mannar. This study aims to determine the length–weight relationship, size at first maturity and fecundity of D. zugei. In total of 1,404 individuals were collected from crab nets in two landing sites; Vankalai and Thalvupadu in Gulf of Mannar during the period of September - November, 2018. Disc Width-WD of all the individuals were measured to the nearest mm, body weight was weighed to the nearest gram and sex was determined. The state of maturity of gonads of females was identified through dissection and macroscopic examination of ovaries. Mean ova diameter significantly varied among females according to the different maturity stages (P<0.05). Sex ratio in the catch was 1:1.35 (M: F). Disc width of males ranged from 85-260 mm with a mean of 175.43±22.42 and females ranged from 110-220 mm with a mean of 167.27±17.55. The Disc width-weight relationship was analyzed by Simple Linear Regression using log transformed data and it showed Log W = -0.5923 + 2.364 log WD for male and Log W = -3.497 + 2.599 log WD for female. The results show negative allometric growth (b<3) for D. zugei. There was no significant statistical difference (P>0.05) in the male and female regression co-efficient. The size at first maturity was 166.5 mm for female D. zugei. Embryos were found only in females ≥ 160 mm of WD. The maximum fecundity was three embryos per female which is varied with the size of the female. This study reports the first findings on length- weight relationship and size at maturity of D. zugei in Sri Lankan waters.Item Study on Removal Efficiency of Fluoride in Water using Environmentally Friendly, Low Cost Filter System(Uva Wellassa University of Sri Lanka, 2020) Chandrasena, D.M.K.M.; Alwis, W.L.; Thushari, G.G.N.; Abeygunawardana, A.P.; Silva, A.P.R.; Jayarathne, D.S.W.N.; Gayathry, dL.D.Water sources in specific regions of dry zone in Sri Lanka naturally contain high fluoride level than the maximum requirement level of drinking water. The intake of excessive amounts of fluoride in water causes different human health issues. This study was intended to identify the potential of using the biomaterials for an integrated water filtration system to improve the water quality. Based on the literature records, production cost and availability of biomaterials, Areca nut (Areca catechu) husk fiber, Coconut (Cocos nucifera) spathe charcoal and Snake Cucumber (Cucumis melo) seeds were used to identify the fluoride removal rate in water. Fluoride rich natural water was subjected to different biomaterial weight and treatment time combinations during preliminary trials. Based on the results of preliminary trials, the final experiment was conducted in the column systems using four types of integrated water filter setups at different weight ratios between areca nut husk fiber: coconut spathe charcoal {Experimental setups: A (1:1, 25g:25g), B (1:2, 25g:50g), C (1:1, 50g:50g), D (2:1, 50g:25g)} with 3 layers of sand. Equal treatment period (1½ hrs) was used for all 4 column experimental setups since the adsorption capacity of biomaterials depends on the contact time. Fluoride removal efficiency and other water quality parameters were measured in each filter setup. Biomaterials amount in the filter setups had a significant effect on the fluoride level, pH, and Total Dissolved Solids in water (p<0.05). The fluoride removal rate of filter setups was 27.90%, 28.80%, 34.49%, and 43.15% in the A, B, C, and D systems respectively. Although the same biomaterial ratio (1:1) had for the A and C experimental setups, the fluoride removal efficiency was significantly different due to the variations of biomaterials dose in two systems (A: 25g, C: 50g). The most effective filter setup was identified as the integrated system with 50g of areca nut husk fiber and 25g of coconut spathe charcoal considering Sri Lanka Standards for potable water (SLS 614:2013). Turbidity, nitrate, nitrite, phosphate, sulphate, iron, and chloride level of water had recorded the acceptable levels as meeting with drinking water standards after 1½ hrs of the treatment period. The pH of all the filter setup was recorded at the range of 7.1-8.1 within the permissible level for drinking water. In conclusion, areca nut husk fiber and coconut spathe charcoal act as effective, low-cost biomaterials in removing the fluoride from water while maintaining the quality of water. Keywords: Water quality, Biomaterials, Integrated water filter system, Fluoride removal rate, FluorosisItem Study on the Potential Usage of Hygrophila schulli (Neeramulliya) for Removal of Water Hardness as a Method of Phytoremediation(Uva Wellassa University of Sri Lanka, 2020) Rajapaksha, R.A.J.J.; Silva, A.P.R.; Jayarathne, D.S.W.N.; Abeygunawardana, A.P.; Coswatte, A.C.W.W.M.C.L.K; Thushari, G.G.N.; ; ;A high level of water hardness in drinking water is a serious problem in different regions of Sri Lanka. Phytoremediation acts as an effective, environmentally friendly, and lowcost technology for the removal of water hardness. Therefore, the current study was intended to identify the potential usage of Hygrophila schulli (Neeramulliya) for the removal of water hardness using a hydroponic system. This plant was selected for the current study based on traditional beliefs, literature records, and availability in the natural environment. Preliminary trials were conducted to identify the appropriate maturity stage of plants, the number of plants, treatment time, and growth medium of hydroponic system. Based on the above results, final experiments were conducted in two hydroponic systems (Treatment 01: 4 plants, Treatment 02: 5 plants) with 16 L of natural hard water (Initial hardness: 300 mg L-1 CaCO3) in the growth medium of 1:1 ratio of coconut coir: sand using one-month-old H. schulli plants. Three replicates for each of the systems were used during the final experiment. Temperature, pH, Electrical Conductivity, Dissolved Oxygen, and Hardness level of water were measured every 12 hours for 36 hours of the experimental period. According to the results, the number of plants and treatment time had a significant effect on the removal rate of water hardness (p<0.05). The hardness removal efficiency of 2 treatment systems ranges at an average of 3.85-21.25% within 36 hours. This explains the capacity of H. schulli plants in absorbing causative ions responsible for water hardness during the phytoremediation process. The hydroponic system with 5 plants per unit was recorded average 250 mg L-1 of hardness which satisfies the standard level permissible for drinking water after 36 hours of the time. Accordingly, the absorbance level of Ca2+ ions had recorded 10 mg L-1 per single plant of H. schulli. Consequently, the treatment system having 5 plants acts as the most effective hydroponic unit in the removal of water hardness. There was no significant difference between pH, Dissolved Oxygen, Electrical Conductivity level in each experimental system, and treatment time (p>0.05). The current study recommends identifying the applicability of similar hydroponic units for removal of extremely high hardness levels from natural water which is over 500 mg L-1 in certain areas of Sri Lanka. In conclusion, this study reveals the appropriateness of H. schulli for the reduction of hardness level (300 mg L-1 CaCO3) during the water treatment process. Keywords: Hardness Removal Rate, Phytoremediation, Hydroponic system, Water quality parameters, Water treatment