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Assessing the compound impacts of climate change and land use dynamics on future groundwater availability in dry land areas of Sri Lanka
(The National Engineering Reseach & Development Center : Ekala, 2025) Herath, K. R. H. M. O. N.; Gunawardhana, H. G. L. N.
Climate change and land use and land cover (LULC) change are the primary challenges that disrupt groundwater availability. While numerous studies have examined their individual impacts, a critical gap exists in understanding their combined impact on groundwater availability. To address this gap, the present study assesses the compound impacts of climate change and LULC change in the Kumbukkan Oya catchment, a dryland area in southeastern Sri Lanka. The analysis uses hydro meteorological data, groundwater levels, borehole logs, and catchment characteristics such as land use, soil type, and elevation. Climate data were obtained from 1989 to 2011, while the groundwater level data and hydrological data were used from 2022 to 2024 at a mostly daily time step. Groundwater flow was then numerically modeled with MODFLOW. Projected future climate was obtained from the CNRM-CM6-1-HR General Circulation Model (GCM) and downscaled to the local scale using a stochastic Random Forest (RF) machine learning algorithm. Land-use data of 2018 and projected for future conditions were employed in assessing LULC dynamics. According to the result, the model captures the seasonal patterns of decline and recovery, particularly in the upstream, although some overestimation occurred in mid-catchment areas. Future projections indicate a decrease in seasonal rainfall compared to the baseline period, with reduced average rainfall but still frequent extreme events. The future period total rainfall will be 1,552 mm, and the observed total of 1,733 mm. Based on the projected results, groundwater levels are expected to decline by approximately 0.43 m to 0.65 m compared to observed con ditions. Therefore, simulation reveals that the Kumbukkan Oya catchment has some extent of resilience in the groundwater level relative to the projected climate and land use change. However, localized tendencies in the fall in groundwater levels suggest the need for site-specific adaptation responses, particularly over vulnerable recharge zones.
Assess the technical applicability of piezoelectric floor tile energy harvesting as a renewable energy source for public buildings in Sri Lanka
(The National Engineering Reseach & Development Center : Ekala, 2025) Jayasundara, J. A. D. V. S. W.; Kawmudi, W. N.; Samararathne, U. M.; Atthanayake, I. U.
With rising energy demands and diminishing fossil fuel resources, there is an urgent need for sustainable and alternative energy solutions, especially in developing countries like Sri Lanka. High-traffic public buildings present an untapped opportunity to harness human kinetic energy through piezoelectric floor tiles, offering a supplementary renewable energy source. Piezoelectric energy harvesting systems convert mechanical pressure into electrical energy, and when integrated into pedestrian zones of public spaces, they can contribute to localized energy needs. However, challenges such as low energy conversion efficiency, system durability, maintenance concerns, and limited public awareness hinder their widespread adoption. Addressing these concerns, this research evaluates the technological feasibility of implementing piezoelectric floor tiles in Sri Lanka public buildings, using the Colombo Fort Railway station as a case study. Employing a mixed-method approach, including energy output estimations, performance simulations, and stakeholder surveys. The study assessed the potential of piezoelectric flooring to contribute to the daily energy demands of low-power appliances in high-traffic public spaces. The analysis estimates that approximately 83Wh/day could be generated from 200,000 pedestrian footsteps, which is sufficient to power low-consumption devices such as LED, CCTV cameras or smart panels. Comparative analysis reveals piezoelectric floor tiles’ unique advantage for indoor applications, maintaining consistent output regardless of sunlight conditions. Environmental assessments demonstrate significant reductions in indirect carbon emissions compared to conventional power generation methods. When combined with other renewable energy sources like solar power, this technology shows great potential as an additional solution, even though it is insufficient as a stand-alone energy source. The stakeholder analysis also revealed a gap in awareness, emphasizing the importance of education and engagement initiatives to support future adoption. As a conclusion, the study high lights the technical viability of piezoelectric floor tiles as a supplementary renewable source for Sri Lankan public infrastructure and recommends pilot projects and further research and development to test feasibility and performance. The finding con tributes to the foundational knowledge and policymaking efforts required to support innovative energy solutions like piezoelectric energy harvesting in the Sri Lanka context.
Agrarian change in the peasant economy of a paddy producing village in the Southern dry zone of Sri Lanka: The Gambaraya system in transition
(National Science Foundation: Colombo, 2016-11-07) Kumara, Kumudu Kusum
Theatre in politics and politics in theatre: Sri Lankan experience since independence
(National Science Foundation: Colombo, 2016-11-07) Fernando, Michael
Psychological consequences and coping mechanisms of bomb blast survivors: the experience of six civilian victims in the city of Colombo
(National Science Foundation: Colombo, 2016-11-07) De Zoysa, Piyanjali; Weerasingha, Tissa