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Item Change detection in the channel segment of Negombo Estuary, Sri Lanka using time series satellite data and its possible impacts on estuarine productivity(The Asian Fisheries Society, 2011) Dahanayaka, D.D.G.L.; Tonooka, H.; Wijeyaratne, M.J.S.; Minato, A.; Ozawa, S.Item Continues monitoring of environmental radioactivity in the area polluted by the Fukushima Nuclear Power Plant Accident 2011 and disclosure of the data to public through the Internet(Department of Zoology and Environmental Management, University of Kelaniya, Kelaniya, Sri Lanka., 2016) Fuse, M.; Miura. S.; Ozawa, S.The Internet has become a powerful communication media. In authors’ previous paper, it has been shown that the Internet can be a good risk communication tool in panic situations caused by natural disasters. The present paper deals with the role of the media in the recovering process from the disaster. It is five years since the earthquake of the magnitude 9.0 occurred at the bottom of the Pacific Ocean near the coast of Northern Japan. There occurred nuclear accidents triggered by the tsunami at the Fukushima Nuclear Power Plants (FNPP). They experienced wide range of radioactive contaminations. Many people had to evacuate from the polluted lands. Even today, about 100,000 people in the Fukushima Prefecture cannot come back to their home lands. The National Institute of Technology, Fukushima College (NITFC) is located at 40km south of the FNPP. About 100 students (10% of total students) had their home lands in the risky 30km region from the FNPP. Some staffs and students of NITFC have been monitoring the radioactivity of their environment since just after the accident and they continued to open their data to public through the Internet. This paper discusses influence of giving different source data to the public beside the official governmental data regarding the radioactivity of the environment.Item Use of ICT for monitoring environment radioactivity and decontamination of sea water polluted by Fukushima Nuclear Power Plant accident(Department of Zoology and Environmental Management, University of Kelaniya, Kelaniya, Sri Lanka., 2016) Ishizaki, E.; Fuse, M.; Minato, A.; Itaba, M.; Ozawa, S.The Fukushima radioactive contamination has occurred by the nuclear plant accident which was caused by the earthquake and tsunami attack in March 2011. The various recovering efforts have been carried out in the last five years. This paper deals with decontamination of radioactive sea water and monitoring of environmental radioactivity. The method of radioactive decontamination of land is scratching the surface of land and mechanical removals of the contaminated soil. The effect of this method is discussed by comparing with the monitoring data of environmental radioactivity. The decontamination of radioactive sea water is based on adsorption of radioactive materials on molecular sheave adsorber. The development of a new adsorber and a plant for the decontamination of radioactive sea water was considered. ICT has been conveniently used in the designing and testing processes of the plant. What we learnt from the recovering processes from the radioactive contamination has been accumulated in the KISSEL (Knowledge Integration Servers for E-Learning) servers. The knowledge can be shared with various people in Asia Pacific countries. It will be used in future in educational purposes as well as in research activities of environmental sciences.Item Mobile Applications for Language Education in the Pacific(Department of Zoology and Environmental Management, University of Kelaniya, Kelaniya, Sri Lanka., 2016) Ualesi, E.T.; Ozawa, S.The rapid developments and usage of mobile apps worldwide prompts the idea of producing a mobile app particularly for language education. This study shows the development of a basic language education app to assist learners who are interested in learning some of the Pacific Languages. Most islanders living abroad cannot speak their native languages fluently especially the young children. Nowadays, nearly every person has access to mobile devices and it is not only a tool for communication but for learning. In this study, we used the Android platform to design and build a simple language app which is then implemented and tested. It is then released for distribution subsequently for users to download. The evaluation will be based on the user’s feedback and reviews after they used the app. Positive results were expected and were also achieved. Many users are interested in these mobile applications and are requesting more features to be added. This is taken as further consideration and will be another extended project to improve future mobile learning in the Pacific.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 Evaluation of Chlorophyll retrieval algorithm using an intermittently closed tidal estuary: The Chilaw lagoon in the west coast of Sri Lanka(Remote Sensing Society of Japan (RSSJ), 2011) Dahanayaka, D.D.G.L.; Tonooka, H.; Wijeyaratne, M.J.S.; Minato, A.; Ozawa, S.Item Preliminary estimation of chlorophyll concentration in a tropical coastal lagoon in Sri Lanka(Remote Sensing Society of Japan (RSSJ), 2010) Dahanayaka, D.D.G.L.; Tonooka, H.; Minato, A.; Dassanayaka, G.; Wijeyaratne, M.J.S.; Ozawa, S.Item Retrieval of Chlorophyll- a using satellite and ground spectral data in Japanese and Sri Lankan water bodies(SPIE, 2012) Dahanayaka, D.D.G.L.; Tonooka, H.; Wijeyaratne, M.J.S.; Minato, A.; Ozawa, S.The suitability of a handheld spectrometer and ASTER satellite data for monitoring water quality in coastal waters of Sri Lanka and inland waters of Japan was tested in November 2010 to March 2012. In-situ Chlorophyll-a (Chl-a), turbidity, total suspended solid, secchi depth and reflectance data were measured at ASTER overpass times in Negombo estuary, Trincomalee bay, Puttalam and Chilaw lagoons, Sri Lanka, and in Lake Senba and Lake Kasumigaura, Japan. ASTER based Chl-a retrieval algorithms were developed support with in-situ Chl-a and MODIS OC3 Chl-a. The original MODIS Chl-a and the in-situ Chl-a were regressively analyzed for determination of a MODIS Chl-a correction equation because it may overestimate in tropical coastal waters. Then, three ASTER VNIR band ratios were compared for correlation with the corrected MODIS Chl-a and in-situ Chl-a. Finally, the regression equation of the ASTER band ratio, B1/B2, with highest correlation was used for generation of high-resolution Chl-a distribution maps. Significant correlation between the ratio of the reflectance peak at 705 nm and the Chl-a absorption at 678 nm and the in-situ Chl-a content was observed and these reflectance ratios were used to establish spectrometric Chl-a estimation algorithms. The proposed algorithms successfully determined localized environmental effects in the study areas. ASTER-based high resolution Chl-a distribution maps will be derived more precisely by further correction of these algorithms, which will be useful in mitigate impacts of the environment change in those coastal and inland water environments. © (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.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.
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