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Item Monitoring eutrophication trends in Bolgoda North Lake, Sri Lanka by Satellite Remote Sensing(Central Fisheries Research Institute (CFRI) Trabzon, Turkey in cooperation with Japan International Cooperation Agency (JICA), Japan, 2016) Dahanayaka, D.D.G.L.; Perera, B.D.C.; Wijeyaratne, M.J.S.; Tonooka, H.This study was aimed to determine the present level and past trends of eutrophication of the Bolgoda North lake, Sri Lanka using in situ Chlorophyll-a (Chl-a) measurements and remote sensing data obtained from Advanced Space-borne Thermal Emission and Reflectance Radiometer (ASTER) satellite data. From March to October 2013, Chl-a, nitrate and phosphate contents of the lake were measured once a month on the days of ASTER overpass and using standard laboratory methods. Cloud-free ASTER images of the lake for the 2000-2013 period were atmospherically corrected using Fast Line-ofsight Atmospheric Analysis of Hypercubes (FLAASH) and in-situ Chl-a data were regressed with atmospherically corrected three ASTER Visible and Near Infrared band ratios of the same date. The green/red band ratio, which had the highest coefficient of determination, was used to develop algorithm for generation of 15-m resolution Chl-a distribution maps. Results indicated that eutrophication of this lake has increased from 2008 to 2011. Heavy eutrophic conditions were noted in several regions of the lake in 2013, especially in water stagnant areas and adjacent to freshwater inlets. Unplanned urbanization and inadequate facilities for waste management have resulted in heavy eutrophication of the water body. If the present trends of waste disposal and unplanned urbanization continue, enormous environmental problems would be resulted in future.Item External Quality Assessment of Higher National Diploma Programmes Offered in Sri Lanka: An Account of Best Practices(South Eastern University of Sri Lanka, 2013) Bandara, T.H.S.S.; Wijeyaratne, M.J.S.Quality assurance activities that are carried out in the Sri Lankan university system since 2002 were introduced to the alternative higher education sector in 2010. External quality assessment reviews of Higher National Diploma (HND)programme offered in eleven Advanced Technological Institutes (ATIs) located in different regions of the country were carried out to identify the best practices, strengths and weaknesses and make suitable recommendations to improve the quality of those programmes. The aspects reviewed were curriculum design, content and review; teaching, learning and assessment methods; quality of students, their progress and achievements; use of student feedback; peer observation; skills development; and academic guidance and counseling. The objective of the present study was to determine whether there are regional differences among ATIs when best practices that are in place in different HND programmes are considered. Best practices identified by the reviewers in external quality assessment review reports of HND programmes in Accountancy, Agriculture, Business administration, English, Information Technology and Management conducted in Ampara, Dehiwala, Jaffna, Kandy, Kegalle, Kurunegala, Labuduwa and Trincomalee ATIs were analysed using Principal Component Analysis to determine whether there are regional differences among ATIs with respect to best practices that are in place in each programme. Results indicated that the good practices identified by reviewers in different HND programmes do not depend on the location of the ATI, the ethnicity of the majority community and prevalence of deterrent factors such as armed secessionist conflicts in the area. Differences in the resources available and the motivation and dedication of the staff may have contributed to the differences in the good practices that are in place in different ATIs.Item Coastal water body database to monitor the water quality and land use changes from remote sensing data(Remote Sensing Society of Japan (RSSJ), 2012) Dahanayaka, D.D.G.L.; Tonooka, H.; Wijeyaratne, M.J.S.; Minato, A.; Ozawa, S.Item Feasibility Study for the Estimation of the Chlrophyll-a Using ASTER Data in an Eutrophic Lake, Sri Lanka(Japan Geoscience Union, Japan., 2014) Dahanayaka, D.D.G.L.; Tonooka, H.; Wijeyaratne, M.J.S.; Minato, A.; Ozawa, S.The objective of this study is to evaluate the performance of the previously proposed band ratio approach in estimating Chl-a in Bolgoda Lake, Sri Lanka as a representative example of Case II waters. Lake is located at western province in an area with lot of industries and also with some agricultural activities. Considerable amount of industrial effluents are discharged into it. Illegal filling and also encroachment has occurred in the recent past. This study focused on to determine the trends in eutrophication via Chl-a changes during the recent past, make predictions and recommend mitigatory measures and suggest precautionary measures to restore the environment. From March to December 2013, water samples at 5 points of Lake were collected once per month parallel to ASTER overpass and Chl-a of each sample was measured using a laboratory spectrophotometer. Cloud-free ASTER scenes acquired over Lake under clear sky conditions were selected during 2000 to 2013 for Chl-a estimation and trend analysis. All the ASTER images were atmospherically corrected using FLAASH and in-situ Chl-a data on Lake were regressively analyzed with atmospherically corrected three ASTER VNIR band ratios such as B1/B2 of the same date. Finally, the regression equation of the band ratio with highest correlation (B1/B2; R2 = 0.78) was used to develop algorithm for generation of 15-m resolution Chl-a distribution maps using atmospherically corrected time series satellite imageries in day by day basis. This method applied for ASTER band 1/2 ratio due to Chl-a is positively correlated with the green band reflectance and negatively correlated with the red band reflectance. Therefore, the reflectance ratio of green and red bands becomes a robust parameter to estimate the Chl-a content. According to the ASTER based Chl-a distribution maps it is clearly evident that eutrophication of the Bolgoda Lake has been gradually increased from 2005-2011. Further, results showed that there were significant eutrophic conditions throughout the year 2013 in several parts of the Lake and considerable spatial heterogeneity with higher concentrations being recorded water stagnant areas and in water adjacent to freshwater outlets. It is clear that Bolgoda Lake is apparently a disposal site of various discharges of factories in addition to poor drainage and sewage systems present in this area. Highly unplanned urbanization and absolutely lack of adequate waste disposal management facilities in industries close to Lake have resulted in pollution of water. If the present trend of waste disposal and unplanned urbanization continue, they would create enormous environmental problems in future. Results of the present study showed that information from satellite remote sensing can play a useful role in determining the changes in Chl-a related to eutrophication in Bolgoda Lake and in the development of time series Chl-a distribution maps. Such information is important for the future predictions, development and management of this area as well as in the conservation of biodiversity. Therefore we recommend incorporation with this technique for routine monitoring of water quality using multi satellite data such as ASTER in inland water bodies like Bolgoda Lake in the future.Item Integration of multisource data for chlorophyll-a monitoring in Negombo estuary, Sri Lanka(IEEE, 2011) Dahanayaka, D.D.G.L.; Tonooka, H.; Wijeyaratne, M.J.S.; Minato, A.; Ozawa, S.In order to estimate chlorophyll-a concentration (Chl-a) for tropical coastal estuarine environments using satellite optical sensor, observations were conducted from 1987 to 2009 in Negombo estuary, Sri Lanka, with support with available in-situ measurements. Landsat band ratios were regressively analyzed with available in-situ Chl-a data. This relationship was used for correcting MODIS OC3 Chl-a values, and then ASTER band ratios were regressively analyzed with the corrected MODIS values. The regression equations obtained for ASTER and Landsat were used to develop algorithms for generation of 15m and 30m resolution Chl-a distribution maps, respectively, in Negombo estuary using atmospherically-corrected time-series imageries. The results indicate that some parts of the estuary have increased eutrophication conditions during 1987-2009.Item Development of coastal water body database on KISSEL server(IEEE, 2012) Dahanayaka, D.D.G.L.; Tonooka, H.; Wijeyaratne, M.J.S.; Minato, A.; Ozawa, S.Monitoring of coastal water bodies in all the relevant aspects was highly important for the sustainable use of those. To achieve this all the research findings should be easy access and presenting those in a user friendly manner will be more advantage. In Sri Lanka, there was not fully or never developed database on research findings especially on coastal water bodies. Thus we developed a Sri Lankan coastal water body database (CWBDS) on KISSEL server system which can be benefitted all the interest communities including general public. Presently it include water quality data over two decades of lagoons and estuaries and in near future it will update with support from universities and research organizations including research on biodiversity, fisheries, land use, socio economics, topography, water circulation, pollution etc.Item The Effects of leaving central bare areas in traditional circular brush-parks on the yield of fish in the brush-park fishery in Negombo estuary, Sri Lanka.(Japan International Marine Science and Technology Federation, 1995) Costa, H.H.; Wijeyaratne, M.J.S.