N. D. K. Dayawansa
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View article: An Approach for Common Web GIS Platform for Agriculture Sector Modernization in Sri Lanka
An Approach for Common Web GIS Platform for Agriculture Sector Modernization in Sri Lanka Open
The status of innovative technology adoption in the Sri Lankan agriculture sector is significantly low. A detailed study conducted by the Department of Agriculture, Sri Lanka and TRCSL, with the assistance of FAO – UN, clearly identified t…
View article: Analysis of Spatial and Temporal Variation of Water Quality: A Case Study of Kotagala Wetland, Nuwara Eliya, Sri Lanka
Analysis of Spatial and Temporal Variation of Water Quality: A Case Study of Kotagala Wetland, Nuwara Eliya, Sri Lanka Open
Water quality of wetland ecosystems is a critical concern due to its implications on human health and aquatic life. This study was conducted to assess the spatial and temporal variation of water quality in Kotagala wetland to understand it…
View article: Are rice systems sustainable in Sri Lanka? - A case of Deduru Oya reservoir irrigation scheme
Are rice systems sustainable in Sri Lanka? - A case of Deduru Oya reservoir irrigation scheme Open
Sustainable rice systems play a crucial role in achieving sustainable development goals, particularly in countries like Sri Lanka that heavily rely on paddy production. The study aims to examine the economic, social, and environmental sust…
View article: Rainfall and Streamflow Trends in the Upper <em>Maduru Oya</em> Sub-watershed in Sri Lanka: A Comparative Study Using Different Statistical Methods
Rainfall and Streamflow Trends in the Upper <em>Maduru Oya</em> Sub-watershed in Sri Lanka: A Comparative Study Using Different Statistical Methods Open
Analysis of historical data on rainfall and streamflow provides useful information for water resources management in a river basin. The objective of this study was to assess the variations and trend analysis of rainfall and streamflow data…
View article: Vulnerability of Other Field Crop (OFC) Cultivating Farmers to Climatic Variability – A Study in Palugaswewa Cascade and Mahaweli System H in Anuradhapura, Sri Lanka
Vulnerability of Other Field Crop (OFC) Cultivating Farmers to Climatic Variability – A Study in Palugaswewa Cascade and Mahaweli System H in Anuradhapura, Sri Lanka Open
Frequently occurring extreme weather events have caused agricultural production losses in considerable amounts in the dry zone of Sri Lanka. Hence, it is important to understand the farmer groups and the systems that are highly vulnerable …
View article: Spatio-temporal analysis of water quality for pesticides and other agricultural pollutants in Deduru Oya river basin of Sri Lanka
Spatio-temporal analysis of water quality for pesticides and other agricultural pollutants in Deduru Oya river basin of Sri Lanka Open
The desire to increase agricultural productivity through the high usage of agrochemicals is causing substantial environmental deterioration. Many developing countries lack the capacity to quantify agro-pollution, especially in the case of …
View article: Application of Standard Precipitation Index (SPI) to Assess Rainfall variability in a Major Agricultural Area in Dry Zone of Sri Lanka
Application of Standard Precipitation Index (SPI) to Assess Rainfall variability in a Major Agricultural Area in Dry Zone of Sri Lanka Open
Agriculture in the dry zone of Sri Lanka is highly constrained by the inadequacy of irrigation water. The small village tanks located in these areas help farmers to cultivate their lands during dry periods by storing rainwater. However, th…
View article: Runoff Prediction in an Ungauged Catchment of Upper Deduru Oya Basin, Sri Lanka: A Comparison of HEC-HMS and WEAP Models
Runoff Prediction in an Ungauged Catchment of Upper Deduru Oya Basin, Sri Lanka: A Comparison of HEC-HMS and WEAP Models Open
Runoff prediction from ungauged catchment has always been a challenging task, requires transfer of hydrologic information from gauged to ungauged catchments. However, it is not clear whether information transfer among nearby catchments is …
View article: Detection and Mapping of Spatial Distribution of Floating Algae in Batticaloa Lagoon, Sri Lanka Using Remote Sensing & GIS
Detection and Mapping of Spatial Distribution of Floating Algae in Batticaloa Lagoon, Sri Lanka Using Remote Sensing & GIS Open
This study intended to detect and map the spatial distribution of floating algae (FAg) in Batticaloa Lagoon in Sri Lanka using sub-pixel classification of satellite imagery and to assess the impact of land use/ land cover (LULC) and water …
View article: Analysis of Forest Cover Loss in <em>Wilpattu</em> forest complex: a remotely sensed change detection and fragmentation analysis
Analysis of Forest Cover Loss in <em>Wilpattu</em> forest complex: a remotely sensed change detection and fragmentation analysis Open
Wilpattu Forest complex is the largest protected area in Sri Lanka and it is a designated Ramsar wetland cluster. It contains a range of diverse terrestrial habitats including various forest types and a coastline with large coasta…
View article: Biomass assessment of floating aquatic plant <em>Eichhornia crassipes</em> - a study in Batticaloa Lagoon, Sri Lanka using sentinel 2A satellite images
Biomass assessment of floating aquatic plant <em>Eichhornia crassipes</em> - a study in Batticaloa Lagoon, Sri Lanka using sentinel 2A satellite images Open
Batticaloa Lagoon is one of the estuaries in the country which is frequently affected by floating aquatic plants; mainly Eichhornia crassipes. The present study aimed to develop a relationship between field measured and satellite …
View article: Identification of drought prone areas in Sri Lanka using multi-temporal satellite data
Identification of drought prone areas in Sri Lanka using multi-temporal satellite data Open
Drought is an insidious hazard of nature with a slower onset and is often misunderstood as a minor weather hazard. Nevertheless, it has become a common and recurring natural disaster in Sri Lanka during recent times affecting the livelihoo…
View article: A gendered analysis on adaptation to resettlement stress: case studies from Deduru Oya reservoir project in Sri Lanka
A gendered analysis on adaptation to resettlement stress: case studies from Deduru Oya reservoir project in Sri Lanka Open
Dam constructions and flow modifications lead a nation towards significant development. Other than expected positive outcomes, a dam can contribute to severe negative impacts on society and environment. Displacement and resettlement due to…
View article: Situation analysis of socio environmental aspects of non point source water pollution in intensively cultivated areas of Nuwara Eliya
Situation analysis of socio environmental aspects of non point source water pollution in intensively cultivated areas of Nuwara Eliya Open
Nonpoint source water pollution is one of the most critical pollution problems all over the world. This study was conducted to assess the status of water pollution, prevention and management and to investigate the awareness of farmers abou…
View article: Impacts of climate change on irrigation water demand of paddy: a case study from <i>Hakwatuna Oya</i> irrigation scheme in Sri Lanka
Impacts of climate change on irrigation water demand of paddy: a case study from <i>Hakwatuna Oya</i> irrigation scheme in Sri Lanka Open
Assessment of irrigation water requirement (IWR) is a prerequisite for planning and management of an irrigation scheme, particularly for a water short scheme. In this context, this study was conducted to estimate the current and future IWR…
View article: Water regimes and ecosystem in lowland paddy field: a case study in Awlegama, Kurunegala, Sri Lanka
Water regimes and ecosystem in lowland paddy field: a case study in Awlegama, Kurunegala, Sri Lanka Open
Paddy fields are manmade ecosystems. These fields undergo three water regimes namely, aquatic, semi aquatic and terrestrial within a cultivation season. Accordingly, the ecosystem also changes. In addition, agronomic practices can affect b…
View article: Assessment of environmental flow release from Deduruoya reservoir to mitigate possible impacts on downstream ecosystem
Assessment of environmental flow release from Deduruoya reservoir to mitigate possible impacts on downstream ecosystem Open
River ecosystems are interlinked with river hydrology. However, construction of dams can modify the natural flow patterns which can lead to unpredictable consequences. Environmental flow (EF) releases can restore ecosystems or reverse the …
View article: Land use changes resulting from construction of Deduru oya reservoir and its’ impacts on livelihood
Land use changes resulting from construction of Deduru oya reservoir and its’ impacts on livelihood Open
Construction of a large dam is one of the major economic and development activities that change the existing land use patterns in an area. The major visible impact of dam construction is the inundation of important land uses/ land cover in…
View article: Water conflicts among different water users and uses in the <em>Hakwatuna Oya</em> watershed in the <em>Deduru Oya</em> basin, Sri Lanka
Water conflicts among different water users and uses in the <em>Hakwatuna Oya</em> watershed in the <em>Deduru Oya</em> basin, Sri Lanka Open
Scarcity of water is the main problem of agriculture and other livelihoods of Hakwatuna Oya watershed in Deduru Oya basin which leads to conflicts among different water users and uses. With this background, a study was conducted to find wa…
View article: Evaluation of groundwater quality for irrigation in <em>Malwathu Oya</em> cascade-I in Anuradhapura District of Sri Lanka
Evaluation of groundwater quality for irrigation in <em>Malwathu Oya</em> cascade-I in Anuradhapura District of Sri Lanka Open
Agro-wells (shallow agricultural wells) serve as the main source of water for irrigation of agricultural crops in dry zone of Sri Lanka. Agro-wells are extensively used by the farmers in Malwathu Oya Cascade-I, located in dry …
View article: Assessment of the suitability of temperature and relative humidity for rice cultivation in rainfed lowland paddy fields in Kurunegala district
Assessment of the suitability of temperature and relative humidity for rice cultivation in rainfed lowland paddy fields in Kurunegala district Open
Climatic suitability analysis is a prerequisite to achieve optimum utilization of the available resources in rainfed rice cultivation. Therefore, a study was conducted to assess the climatic factors and to map their suitability for rainfed…
View article: Above ground biomass estimation of mangroves located in Negombo - Muthurajawela wetland in Sri Lanka using ALOS PALSAR Images
Above ground biomass estimation of mangroves located in Negombo - Muthurajawela wetland in Sri Lanka using ALOS PALSAR Images Open
In Sri Lanka, mangrove forests are scattered along the north-western, north eastern, Jaffna Peninsula and eastern coastal belt. The total estimated extent of mangroves in the country is about 87 km2. Estimation of Above Ground B…
View article: Impacts of land cover dynamics and shallow groundwater abstraction on sustainability of <em>Hakwatuna Oya</em> irrigation system
Impacts of land cover dynamics and shallow groundwater abstraction on sustainability of <em>Hakwatuna Oya</em> irrigation system Open
Deforestation, expansion of agriculture and over abstraction of groundwater in watersheds can influence the water yield. Hakwatuna Oya watershed area in Deduru Oya basin also faces a similar situation due to rapid land use/cover changes an…
View article: Seasonal variation of leaching of nitrate under onion cultivation in sandy regosols uncl its predictions by LEACHM-N
Seasonal variation of leaching of nitrate under onion cultivation in sandy regosols uncl its predictions by LEACHM-N Open
by LEACHM-R{
View article: Spatio-temporal Analysis of Urbanization, Urban Growth and Urban Sprawl Since 1976-2011 in Kandy City and Surrounding Area using GIS and Remote Sensing
Spatio-temporal Analysis of Urbanization, Urban Growth and Urban Sprawl Since 1976-2011 in Kandy City and Surrounding Area using GIS and Remote Sensing Open
Bhumi is published by the Town & Country Planning Research Institute of the University of Moratuwa, Sri Lanka and the La Trobe University, Australia.Bhumi serves a wide range of subject areas directly and indirectly related to Urban and Ru…
View article: Assessment of spatial distribution and estimation of biomass of Prosopis juliflora (Sw.) DC. in Puttlam to mannar region of Sri Lanka using remote sensing and GIS
Assessment of spatial distribution and estimation of biomass of Prosopis juliflora (Sw.) DC. in Puttlam to mannar region of Sri Lanka using remote sensing and GIS Open
Prosopis juliflora (Sw.) DC. has been introduced to Hambantota District in the southern province of Sri Lanka during early 1950’s to rehabilitate salt affected soils in the coastal area and for firewood purposes. Within a very sho…
View article: Variability of some important soil chemical properties of rainfed low land paddy fields and its effect on land suitability for rice cultivation
Variability of some important soil chemical properties of rainfed low land paddy fields and its effect on land suitability for rice cultivation Open
Available soil-phosphorus (P), exchangeable soil-potassium (K), soil pH and soil Electrical Conductivity (EC) affect rice production and are highly variable in nature mainly due to the variability in water availability. Therefore, experime…
View article: Estimation of above ground biomass in Horton Plains National Park, Sri Lanka using Optical, thermal and RADAR remote sensing data
Estimation of above ground biomass in Horton Plains National Park, Sri Lanka using Optical, thermal and RADAR remote sensing data Open
A variety of approaches have been developed to estimate the aboveground biomass. However, methods differ in procedure, complexity and time requirement depending on the specific aim of these estimations. Remote Sensing (RS) is popular as a …
View article: Comparative performance assessment of major irrigation systems in Upper Deduru Oya Basin
Comparative performance assessment of major irrigation systems in Upper Deduru Oya Basin Open
Performance assessment of irrigation systems plays a vital role to self-evaluate them so that interventions could be made to improve the functioning of the systems. This study was conducted to assess water delivery and supply performances …
View article: Seasonal changes in home range and habitat use of elephants in Southern and north-central provinces of Sri Lanka
Seasonal changes in home range and habitat use of elephants in Southern and north-central provinces of Sri Lanka Open
Elephants generally require a large area of habitat, and usually avoid human settlements and agricultural lands. However, less protected agricultural lands such as Chenas are vulnerable during droughts where food is scarce. If available, g…