Browsing by Author "Silva, A.P.R."
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Item 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 LankaItem 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, 2019-02) Silva, A.P.R.; Rathnasuriya, M.I.G.; Guruge, K.P.G.K.P.; Jayasinghe, R.P.P.K.Fundamental understanding of fish resources has become an urgent need in Sri Lanka for the sustainable management of fish stocks. As studies on ichthyoplankton (fish eggs and larvae) in Sri Lankan coastal waters are scarce, a preliminary study was carried out with the aim to find the abundance, distribution and composition 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 where human interactions are relatively high. Horizontal surface sample and a vertical sample were collected from each station using Working Party 2 (WP2) plankton net (180 µm mesh size) for three months in 2018: March, September and October representing 1st inter-monsoon, Southwest monsoon and 2nd inter-monsoon respectively. Fish eggs and larvae were separated from plankton and identified to the lowest possible taxonomic level under the stereo microscope using the standard keys. A total of 4095 fish eggs and 465 fish larvae belonging to 23 families were collected from the study area. An average abundance of 8772 eggs and 996 larvae per 1000 m3 were recorded. Most abundant taxonomic level in each month were, Family Siganidae in March, Family Blennidae in September and Order Clupeiformes in October. The highest abundance of fish eggs was found in Station 3 (22158 per 1000 m3 in vertical sample and 13934 per 1000 m3 in horizontal surface sample) and larvae was found in Station 4 (1196 per 1000 m3 in vertical sample and 2537 per 1000 m3 in horizontal surface sample) which is located adjacent to Maha Oya estuary, showing estuaries’ ecological services as nursery grounds for early stages of fish. 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.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 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 A Preliminary Study on Potentials of Seaweed Culture as an Alternative Livelihood for Small Scale Fishing Community in Southern Coast of Sri Lanka(Uva Wellassa University of Sri Lanka, 2020) Gayathry, L.D.; Silva, A.P.R.; Shanuke, D.S.; Wijethunge, H.N.S.; Egodauyana, K.P.U.T.; Dharmakeerthi, T.N.; Jayarathna, W.N.D.S.; Bambaranda, B.V.A.S.M.Large scale seaweed mariculture is widespread in many Asian countries for decades. But Sri Lanka is still in its infancy. Therefore, promoting seaweed mariculture as a commercialscale industry is an urged necessity. Seaweeds grow abundantly along the southern coast of Sri Lanka. Therefore, the study attempted to assess the socio-economic status of small-scale fishermen, the potentiality of using seaweed culture as an alternative livelihood, and awareness of fishermen regarding seaweed culture on the southern coast of Sri Lanka. Data were collected by key-informant interviews and questionnaire surveys from November 2019 to February 2020. Cluster sampling was used to draw a sample of 160 fishermen from 8 major landing sites. Results of the socio-economic analysis showed that 72% of fishermen were between the age group of 35 - 55 years. Due to the seasonality of fishing, 65% of fishermen are having below-average monthly income (LKR 12,000 - 15,000). In three landing sites, 25% of fishermen are seasonal fishers. But almost all fishers are active in other landing sites. In total, 90% of fishermen are interested in seaweed farming. Identified reasons for their interest in seaweed culture were, additional income (85%), manageable with fishing (65%), and women empowerment (58%). Results relevant to awareness on seaweed farming among fishermen 80 - 90% in four landing sites, 60 - 65% in two landing sites, and below 30% in the other two landing sites. Favorable environmental conditions, adequate workforce, and willingness to initiate seaweed culture were identified as potentials. Absence of proper mechanism to disseminate knowledge, financial support, and lack of knowledge on marketing were identified as constraints for the initiation of seaweed farming. Accordingly, knowledge regarding seaweed farming should be disseminated and effectively transferred. The overall results indicate greater potential to initiate seaweed mariculture as an alternative livelihood for small scale fishing communities in southern Sri Lanka. Keywords: Seaweed, Mariculture, Fishing community, Alternative livelihood, Southern coastItem 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 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