Browsing by Author "Abenayake, C"

Now showing 1 - 9 of 9

item: Conference-Full-text
Conflicting interactions between elephant habitats and human settlements; a case of Hambanthota
(Department of Architecture, University of Moratuwa, Sri Lanka, 2019-11-14) Herat, HMM; Abenayake, C; Wattege, P; Fernando, KD; Dayaratne, R
Conflicts between human and elephants are one of the most widespread regional issues in Sri Lanka, particularly in the dry zone. Moreover, human-elephant conflict is increasing, predominantly in areas where expansion of human settlements cultivation, water sources and other developments. Human-elephant conflicts in these regions are increasing despite the management interventions of the government authorities. The impact of human-elephant conflict may take several forms including human death, agricultural crop losses, infrastructural damages and disturbances to the daily routine of the community such as travel to work and school. Habitat fragmentation and habitat loss can be considered as the main reasons for increasing human-elephant conflicts. Habitat fragmentation can be defined as a landscape ecological process involving both habitat shrinking and the dissection of habitat. There is a strong relationship between the habitat fragmentation and the habitat loss. This research work analyses how habitat fragmentation as a process affects on habitat loss of elephants and human-elephant conflicts in Hambanthota region. Therefore, this research questions the causative factors for increasing elephant human conflicts in Hambanthota region based on the information collected through secondary sources, key informant interviews and field observations. Further this research discusses how to manage the human settlements development coherent with the biodiversity particularly elephants’ habitats. The paper recommends how to adopt the concept of co-management in order to achieve the twin objectives of biodiversity conservation and safeguarding human security in the process of spatial strategy making.
item: Conference-Extended-Abstract
Decision tree application for model built-up land fragmentation in urban areas
(2021) Ranaweera, N; Jayasinghe, A; Abenayake, C
Land fragmentation can define as the “situation where one area/unit is composed of a large number of parcels that are too small for their rational utilization” [5]. Land fragmentation affects sustainable development through its multiple impacts on environmental, economic, and social costs [13]. Effective land use management and policy decisions are always based on understanding, modeling, and predicting land-use changes in cities [9]. Therefore, the land fragmentation process should systematically investigate to provide a wide-ranging set of land use indicators to support sustainable development [12]. Built-up land fragmentation is the fragmentation or division of the built-up plots or units within the built-up land-use area horizontally. The objective of this study is to frame a Decision Tree (DT) model to identify the non-linear relationships between the Level of Built-up Land Fragmentation (LBLF) and its influencing factors in urban areas. The sub-objective is to quantify the LBLF in the Western Province, Sri Lanka. The study scope limits to LBLF and Decision Tree (DT) non-linear classifier. The study further quantifies the LBLF from 2000 to 2010 in Western Province, Sri Lanka as an initiation to frame the DT model.
item: Article-Full-text
Ecosystem services-based composite indicator for assessing community resilience to floods
(Elsevier, 2018) Abenayake, C; Mikami, Y; Matsuda, Y; Jayasinghe, A
Disaster resilience studies have acknowledged the role of the natural environment in reinforcing community resilience; however, pragmatic environmental indicators are lacking, particularly geospatial composite indicators. This paper aims to introduce a composite environmental indicator for assessing community resilience to floods, targeting regional-scale geospatial applications. The composite indicator has been built on conceptualized inter-relationships between Ecosystem Services (ESs) and community resilience. The environmental parameters used to measure the composite were identified by surveying the cross-disciplinary literature from the domains of ESs and disaster resilience. The application of the composite indicator was demonstrated by a case study in Colombo, Sri Lanka. The composite indicator was tested on flood declaration and community response data from Colombo. The application employed a Weighted Linear Combination Method (WLCM) and was executed in a Geographic Information System (GIS)-based platform. The geospatial data for application and validation were collected through secondary sources. The developed composite indicator consists of four proxy indicators (i.e., soil hydraulic properties, slope, land use, and a precipitation factor) and parameters used to measure them. The parameters were also derived from the conceptualized relationship that elaborates ESs into a bundle of services, including flood regulation, climate regulation, and nutrient recycling, whereas many of the existing resilience assessment methodologies focused only on flood regulation. Furthermore, the composite indicator organized the environmental parameters into two tiers, facilitating a range of users. Hence, incorporating this ESs-based composite indicator into existing resilience assessment methodologies could guide community resilience-building initiatives towards more sustainable outcomes.
item: Conference-Full-text
Evaluating the age-friendliness of transport system in Sri Lankan cities
(Sri Lanka Society of Transport and Logistics, 2023-08-26) Ranasinghe, R; Hewawasam, C; Abenayake, C; Gunaruwan, TL
Nowadays as one of the key areas of urban planning and design, health concerns of the community, with high vulnerability on older population have re-appear. Over the time, the elderly population around the world are predicted to increase and Sri Lanka follows the same trend. In this context, the concept of ‘Age-friendly Cities’ introduced by WHO comes to play. WHO has identified, ‘Transport and Mobility’ as one of the eight priority domains for policy action in order to build age-friendly cities. Since without transportation, other facilities and services are inaccessible, transportation plays a major role in a city design. How to effectively understand the age-friendliness of a city’s transport system and diagnose the underlying problems of urban development have therefore become critical in managing this demographic change. Previous studies have not yet provided a proper methodology for quantification of age-friendliness of transport system in Sri Lankan cities. This study aims to evaluate the age-friendliness of transport system in Sri Lankan cities by incorporating quantitative indicator-based examination. Three case study areas; Negombo, Kurunegala and Kandy, were employed and the results show that the age-friendliness of transport system in each city is 59.29%, 68.25% and 66.98% respectively.
item: Article-Full-text
Modelling vegetation land fragmentation in urban areas of Western Province, Sri Lanka using an Artificial Intelligence-based simulation technique
(Public Library of Science, 2023) Jayasinghe, A; Ranaweera, N; Abenayake, C; Bandara, N; De Silva, C
Vegetation land fragmentation has had numerous negative repercussions on sustainable development around the world. Urban planners are currently avidly investigating vegetation land fragmentation due to its effects on sustainable development. The literature has identified a research gap in the development of Artificial Intelligence [AI]-based models to simulate vegetation land fragmentation in urban contexts with multiple affecting elements. As a result, the primary aim of this research is to create an AI-based simulation framework to simulate vegetation land fragmentation in metropolitan settings. The main objective is to use non-linear analysis to identify the factors that contribute to vegetation land fragmentation. The proposed methodology is applied for Western Province, Sri Lanka. Accessibility growth, initial vegetation large patch size, initial vegetation land fragmentation, initial built-up land fragmentation, initial vegetation shape irregularity, initial vegetation circularity, initial building density, and initial vegetation patch association are the main variables used to frame the model among the 20 variables related to patches, corridors, matrix and other. This study created a feed-forward Artificial Neural Network [ANN] using R statistical software to analyze non-linear interactions and their magnitudes. The study likewise utilized WEKA software to create a Decision Tree [DT] modeling framework to explain the effect of variables. According to the ANN olden algorithm, accessibility growth has the maximum importance level [44] between -50 and 50, while DT reveals accessibility growth as the root of the Level of Vegetation Land Fragmentation [LVLF]. Small, irregular, and dispersed vegetation patches are especially vulnerable to fragmentation. As a result, study contributes detech and managing vegetation land fragmentation patterns in urban environments, while opening up vegetation land fragmentation research topics to AI applications.
item: Article-Full-text
Study On Level Of Vegetation Land Fragmentation In Western Province, Sri Lanka
(Faculty of Architecture University of Moratuwa, 2021-12) Ranaweera, MNN; Jayasinghe, AB; Abenayake, C
Muthurajawela Marsh and Negombo Lagoon have lost their marshland and mangroves from 41% and 21% accordingly from 1997 to 2017. Vegetation land fragmentation (VLF) is the foremost reason that accelerates the vegetation cover change. However, Sri Lanka has not been given sufficient attention to investigate VLF with case studies. Further, fragmentation patterns like dissecting, shrinking, and disappearing are still essential to investigate with empirical studies to comprehend the phases of VLF. Therefore, this study attempts to quantify the level of vegetation land fragmentation (LVLF) in the Western Province’s Grama Niladhari Divisions (GNDs) from 2000 to 2020 by applying the Landscape Division Index (FRAGSTATS). It further analyses the patterns of VLF by using 200 fragmented locations. The key findings demonstrate that 54% of GNDs have more than 60% of the LVLF in the Gampaha District from 2000 to 2010. Although it has reduced up to 49% from 2010-2020, the Gampaha District remains in the highest position. It additionally discloses the significant increment in LVLF along the expressways from 2010 to 2020. 46% of fragmented patches indicate the mixed of dissecting, shrinking, and disappearing patterns. Therefore, the study provides methodological application and quantitative insights for planners to investigate VLF and its patterns.
item: Conference-Full-text
Thermal comfort modeling on urban streets
(Sri Lanka Society of Transport and Logistics, 2023-08-26) Mendis, L; Jayasinghe, A; Abenayake, C; Gunaruwan, TL
“Walkability” is a vital constituent on Urban Streets and is a sustainable transportation mode for pedestrians in highly urbanized cities. Psychological comfort of pedestrians is predominantly defined by enhancing walkability on urban streets. Thermal comfort is one of the key attributes for pedestrian comfort and wellbeing. This study considers thermal comfort on urban streets in assessing, walkability by considering the Thermal Heat Indexes (THI) and investigating the Predicted Mean Volt (PMV) values. Empirical data were analyzed and discussed the behavior of measured Air Temperature and Thermal Heat Index (THI) values of selected urban streets. To explore the thermal comfort levels on streets, ENVI-met 4.1 computer simulation and analyzed data on Air temperature, Mean Radiant Temperature (MRT) and Predicted Mean Vote (PMV) values were used. According to the empirical Data, the THI value is higher on Location 01-Main Street than other urban streets. As per the results of the ENVI-met computer simulation, the changing Building Height scenario indicates a significant effect on the thermal comfort as opposed to the tree lines along both sides of the street. Findings from this research express that increasing building height and increasing tree density by proposing a large expanse of vegetation along streets is significantly associated with the thermal comfort conditions on urban streets and enhance the level of walkability as an effective green transport mode.
item: Article-Full-text
Trading disaster:containers and container thinking in the production of climate precarity
(Wiley-Blackwell, 2022) Parsons, L; de Campos, RS; Moncaster, A; Cook, I; Siddiqui, T; Abenayake, C; Jayasinghe, AB; Mishra, P; Billah, T
This paper examines how global trade shapes and intensifies disasters. Juxtaposing three basic, everyday consumer goods – a t-shirt, a brick, and a tea bag – with disasters manifesting in their respective global supply chains, it highlights how climate change, local environmental degradation, and carbon emissions are dynamically shaped by consumption. Analysis of data collected in South and Southeast Asia reveals that local environmental degradation linked to international trade interacts with global climate change and the policies intended to mitigate it, influencing how and where disasters manifest. Underpinning this analysis is the physical and conceptual presence of the container. With more and more of the natural environment packaged and redistributed for global trade, the container thinking that underpins these logistics is increasingly imbricated in environmental processes. Indeed, as this paper aims to show, the container logic that frames analysis of these processes – linked to and drawn from the logistics of global trade – serves as both obfuscator and actor in the global landscape of environmental risk.
item: Article-Full-text
Urban flood modeling application: Assess the effectiveness of building regulation in coping with urban flooding under precipitation uncertainty
(Elsevier, 2021) Piyumi, MMM; Abenayake, C; Jayasinghe, A; Wijegunarathna, E
This research evaluates the effectiveness of planning and building regulations in coping with urban flooding under different precipitation scenarios. Accordingly, the study simulated seven alternative scenarios considering the variations of precipitation, plot coverage regulations, and Low Impact Development (LID) options. The study utilized open-source geospatial software to model different surface runoff scenarios. Then the effectiveness of those seven alternatives was assessed by utilizing the Analytical Hierarchy Process (AHP) technique to evaluate their sustainability in urban design. The results revealed that the plot coverage regulations are effective in managing floods during average rainfall events, and LID-based infrastructure solutions are effective during moderate rainfall events. Nevertheless, none of these solutions were solely adequate during extreme rainfall events. Regardless of the response to extreme rainfall occurrences, the practitioners’ opinion was in favour of green roof adoption and plot coverage regulation considering their effectiveness in managing more frequent average rainfall events, and the overall sustainability in maintaining the balance of urban hydrological pathways. Accordingly, the findings of the study can be utilized as a guide to the decision-making process in urban planning and design, and to formulate sustainable planning regulations and guidelines to cope with urban flooding under the precipitation uncertainty.