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Forest-cover change has become an important topic in global biodiversity conservation in recent decades because of the high rates of forest loss in different parts of the world, especially in the tropical region. While human interventions are the major cause, natural disasters also contribute to forest cover changes. During the past decades, several studies have been conducted to address different aspects of forest cover changes (e.g., drivers of deforestation, degradation, interventions) in different parts of the world. In Sri Lanka, increasing rates of forest loss have been recorded during the last 100 years on a regional basis, especially in the dry zone. However, Sri Lanka needs detailed studies that employ contemporary data and robust analytical tools to understand the patterns of forest cover changes and their drivers. The dry zone of Sri Lanka encompasses 59% of the total land area of the country, ergo, the most extensive forest cover. Our study analyzed forest cover dynamics and its drivers between 1992 and 2019. Our specific objectives included (i) producing a forest cover map for 2019, (ii) analyzing the spatiotemporal patterns of forest cover changes from 1992 to 2019, and (iii) determining the main driving forces. Landsat 8 images were used to develop forest-cover maps for 2019, and the rest of the forest cover maps (1992, 1999, and 2010) were obtained from the Forest Department of Sri Lanka. In this study, we found that the dry zone had undergone rapid forest loss (246,958.4 ha) during the past 27 years, which accounts for 8.0% of the net forest cover changes. From 2010 to 2019, the rates of forest loss were high, and this can be associated with the rapid infrastructure development of the country. The findings of this study can be used as a proxy to reform current forest policies and enhance the forest sustainability of the study area.
Manjula Ranagalage; M. H. J. P. Gunarathna; Thilina D. Surasinghe; Dmslb Dissanayake; Matamyo Simwanda; Yuji Murayama; Takehiro Morimoto; Darius Phiri; Vincent R. Nyirenda; K. T. Premakantha; Anura Sathurusinghe. Multi-Decadal Forest-Cover Dynamics in the Tropical Realm: Past Trends and Policy Insights for Forest Conservation in Dry Zone of Sri Lanka. Forests 2020, 11, 836 .
AMA StyleManjula Ranagalage, M. H. J. P. Gunarathna, Thilina D. Surasinghe, Dmslb Dissanayake, Matamyo Simwanda, Yuji Murayama, Takehiro Morimoto, Darius Phiri, Vincent R. Nyirenda, K. T. Premakantha, Anura Sathurusinghe. Multi-Decadal Forest-Cover Dynamics in the Tropical Realm: Past Trends and Policy Insights for Forest Conservation in Dry Zone of Sri Lanka. Forests. 2020; 11 (8):836.
Chicago/Turabian StyleManjula Ranagalage; M. H. J. P. Gunarathna; Thilina D. Surasinghe; Dmslb Dissanayake; Matamyo Simwanda; Yuji Murayama; Takehiro Morimoto; Darius Phiri; Vincent R. Nyirenda; K. T. Premakantha; Anura Sathurusinghe. 2020. "Multi-Decadal Forest-Cover Dynamics in the Tropical Realm: Past Trends and Policy Insights for Forest Conservation in Dry Zone of Sri Lanka." Forests 11, no. 8: 836.
Changes in the urban landscape resulting from rapid urbanisation and climate change have the potential to increase land surface temperature (LST) and the incidence of the urban heat island (UHI). An increase in urban heat directly affects urban livelihoods and systems. This study investigated the spatiotemporal variation of the UHI in the Kurunegala urban area (KUA) of North-Western Province, Sri Lanka. The KUA is one of the most intensively developing economic and administrative capitals in Sri Lanka with an urban system that is facing climate vulnerabilities and challenges of extreme heat conditions. We examined the UHI formation for the period 1996–2019 and its impact on the urban-systems by exploring nature-based solutions (NBS). This study used annual median temperatures based on Landsat data from 1996 to 2019 using the Google Earth Engine (GEE). Various geospatial approaches, including spectral index-based land use/cover mapping (1996, 2009 and 2019), urban-rural gradient zones, UHI profile, statistics and grid-based analysis, were used to analyse the data. The results revealed that the mean LST increased by 5.5 °C between 1996 and 2019 mainly associated with the expansion pattern of impervious surfaces. The mean LST had a positive correlation with impervious surfaces and a negative correlation with the green spaces in all the three time-points. Impacts due to climate change, including positive temperature and negative rainfall anomalies, contributed to the increase in LST. The study recommends interactively applying NBS to addressing the UHI impacts with effective mitigation and adaptation measures for urban sustainability.
Manjula Ranagalage; Sujith S. Ratnayake; Dmslb Dissanayake; Lalit Kumar; Hasula Wickremasinghe; Jagathdeva Vidanagama; Hanna Cho; Susantha Udagedara; Keshav Kumar Jha; Matamyo Simwanda; Darius Phiri; Enc Perera; Priyantha Muthunayake. Spatiotemporal Variation of Urban Heat Islands for Implementing Nature-Based Solutions: A Case Study of Kurunegala, Sri Lanka. ISPRS International Journal of Geo-Information 2020, 9, 461 .
AMA StyleManjula Ranagalage, Sujith S. Ratnayake, Dmslb Dissanayake, Lalit Kumar, Hasula Wickremasinghe, Jagathdeva Vidanagama, Hanna Cho, Susantha Udagedara, Keshav Kumar Jha, Matamyo Simwanda, Darius Phiri, Enc Perera, Priyantha Muthunayake. Spatiotemporal Variation of Urban Heat Islands for Implementing Nature-Based Solutions: A Case Study of Kurunegala, Sri Lanka. ISPRS International Journal of Geo-Information. 2020; 9 (7):461.
Chicago/Turabian StyleManjula Ranagalage; Sujith S. Ratnayake; Dmslb Dissanayake; Lalit Kumar; Hasula Wickremasinghe; Jagathdeva Vidanagama; Hanna Cho; Susantha Udagedara; Keshav Kumar Jha; Matamyo Simwanda; Darius Phiri; Enc Perera; Priyantha Muthunayake. 2020. "Spatiotemporal Variation of Urban Heat Islands for Implementing Nature-Based Solutions: A Case Study of Kurunegala, Sri Lanka." ISPRS International Journal of Geo-Information 9, no. 7: 461.
Landslides have become a frequent natural hazard and pressing severe environmental issues in Sri Lanka. The upward trend in high-intensity rainfall events, growing population, expansion of plantation, and lifelines increased the landslide risk of the country. Though developed countries adopted in risk assessment-based management, conversely, they rely on conventional landslide hazard assessment-based risk management. Therefore, this study is attempted to create a standardized landslide risk assessment framework, combining susceptibility and vulnerability. In the experimental design, landslide susceptibility was determined by nine (09) landslide causative factors, and fourteen (14) factors assessed for landslide vulnerability. Factors were prepared, standardized, and analyzed according to the level of contribution to susceptibility and vulnerability by using spatial multi-criteria evaluation method and entropy method under geographical information system. Spatial distribution of susceptibility and vulnerability were integrated to obtain the spatial distribution of risk. Analyses indicate that highly susceptible and high vulnerable areas are not demonstrated a high level of risk individually. However, a combination of them creates a high level of risk. The risk was classified into six classes, such as highest, high, moderate, low, lowest, and no risk. The highest-risk and high-risk zones of the area show 257 km2 (15%) and 21% (350 km2) of the total land area, respectively. Moderately risk zones take part 27% (446 km2). However, 22% (375 km2) of land area categorized as low or lowest risk and 15% (255 km2) under the no-risk. The study concluded that the developed framework is transparent and easy to update periodically by the local authorities. Hence, public policymakers can use the findings of this study to plan the future development of the region and the country. In contrast, risk assessment provides essential information to enhance national disaster risk reduction strategies.
E. N. C. Perera; D. T. Jayawardana; Manjula Ranagalage; D M S L B Dissanayake; H. M. D. S. Wijenayaka. Introduce a framework for landslide risk assessment using geospatial analysis: a case study from Kegalle District, Sri Lanka. Modeling Earth Systems and Environment 2020, 6, 2415 -2431.
AMA StyleE. N. C. Perera, D. T. Jayawardana, Manjula Ranagalage, D M S L B Dissanayake, H. M. D. S. Wijenayaka. Introduce a framework for landslide risk assessment using geospatial analysis: a case study from Kegalle District, Sri Lanka. Modeling Earth Systems and Environment. 2020; 6 (4):2415-2431.
Chicago/Turabian StyleE. N. C. Perera; D. T. Jayawardana; Manjula Ranagalage; D M S L B Dissanayake; H. M. D. S. Wijenayaka. 2020. "Introduce a framework for landslide risk assessment using geospatial analysis: a case study from Kegalle District, Sri Lanka." Modeling Earth Systems and Environment 6, no. 4: 2415-2431.
This study investigated the spatiotemporal changes of land use land cover (LULC) and its impact on land surface temperature (LST) in the Galle Municipal Council area (GMCA), Sri Lanka. The same was achieved by employing the multi-temporal satellite data and geo-spatial techniques between 1996 and 2019. The post-classification change detection technique was employed to determine the temporal changes of LULC, and its results were utilized to assess the LST variation over the LULC changes. The results revealed that the area had undergone a drastic LULC transformation. It experienced 38% increase in the built-up area, while vegetation and non-built-up area declined by 26% and 12%, respectively. Rapid urban growth has had a significant effect on the LST, and the built-up area had the highest mean LST of 22.7 °C, 23.2 °C, and 26.3 °C for 1996, 2009, and 2019, correspondingly. The mean LST of the GMCA was 19.2 °C in 1996, 20.1 °C in 2009, and 22.4 °C in 2019. The land area with a temperature above 24 °C increased by 9% and 12% in 2009 and 2019, respectively. The highest LST variation (5.5 °C) was observed from newly added built-up area, which was also transferred from vegetation land. Meanwhile, the lowest mean LST difference was observed from newly added vegetation land. The results show that the mean annual LST increased by 3.2 °C in the last 22 years in GMCA. This study identified significant challenges for urban planners and respective administrative bodies to mitigate and control the negative effect of LST for the long livability of Galle City.
Dmslb Dissanayake. Land Use Change and Its Impacts on Land Surface Temperature in Galle City, Sri Lanka. Climate 2020, 8, 65 .
AMA StyleDmslb Dissanayake. Land Use Change and Its Impacts on Land Surface Temperature in Galle City, Sri Lanka. Climate. 2020; 8 (5):65.
Chicago/Turabian StyleDmslb Dissanayake. 2020. "Land Use Change and Its Impacts on Land Surface Temperature in Galle City, Sri Lanka." Climate 8, no. 5: 65.
The blooming of urban expansion has led to the improvement of urban life, but some of the negative externalities have affected the life quality of urban dwellers, both directly and indirectly. As a result of this, research related to the quality of life has gained much attention among multidisciplinary researchers around the world. A number of attempts have been made by previous researchers to identify, assess, quantify, and map quality of life or well-being under various kinds of perspectives. The objectives of this research were to create a life quality index (LQI) and identify the spatial distribution pattern of LQI in Kandy City, Sri Lanka. Multiple factors were decomposed, a hierarchy was constructed by the multi-criteria decision making (MCDM) method, and 13 factors were selected under two main criteria—environmental and socioeconomic. Pairwise comparison matrices were created, and the weight of each factor was determined by the analytic hierarchy process (AHP). Finally, gradient analysis was employed to examine the spatial distribution pattern of LQI from the city center to the periphery. The results show that socioeconomic factors affect the quality of life more strongly than environmental factors, and the most significant factor is transportation. The highest life quality zones (26% of the total area) were distributed around the city center, while the lowest zones represented only 9% of the whole area. As shown in the gradient analysis, more than 50% of the land in the first five kilometers from the city center comes under the highest life quality zone. This research will provide guidance for the residents and respective administrative bodies to make Kandy City a livable city. It the constructed model can be applied to any geographical area by conducting necessary data calibration.
Dmslb Dissanayake; Takehiro Morimoto; Yuji Murayama; Manjula Ranagalage; Enc Perera. Analysis of Life Quality in a Tropical Mountain City Using a Multi-Criteria Geospatial Technique: A Case Study of Kandy City, Sri Lanka. Sustainability 2020, 12, 2918 .
AMA StyleDmslb Dissanayake, Takehiro Morimoto, Yuji Murayama, Manjula Ranagalage, Enc Perera. Analysis of Life Quality in a Tropical Mountain City Using a Multi-Criteria Geospatial Technique: A Case Study of Kandy City, Sri Lanka. Sustainability. 2020; 12 (7):2918.
Chicago/Turabian StyleDmslb Dissanayake; Takehiro Morimoto; Yuji Murayama; Manjula Ranagalage; Enc Perera. 2020. "Analysis of Life Quality in a Tropical Mountain City Using a Multi-Criteria Geospatial Technique: A Case Study of Kandy City, Sri Lanka." Sustainability 12, no. 7: 2918.
Although urbanization has contributed to improving living conditions, it has had negative impacts on the natural environment in urbanized areas. Urbanization has changed the urban landscape and resulted in increasing land surface temperature (LST). Thus, studies related to LST in various urban environments have become popular. However, there are few LST studies focusing on mountain landscapes (i.e., hill stations). Therefore, this study investigated the changes in the landscape and their impacts on LST intensity (LSTI) in the tropical mountain city of Nuwara Eliya, Sri Lanka. The study utilized annual median temperatures extracted from Landsat data collected from 1996 to 2017 based on the Google Earth Engine (GEE) interface. The fractions of built-up (BL), forested (FL) and agricultural (AL) land, were calculated using land use and cover maps based on urban–rural zone (URZ) analysis. The urban–rural margin was demarcated based on the fractions of BL (<10%), and LSTI that were measured using the mean LST difference in the urban–rural zone. Besides, the mixture of land-use types was calculated using the AL/FL and BL/FL fraction ratios, and grid-based density analysis. The results revealed that the BL in all URZs rapidly developed, while AL decreased during the period 1996 to 2017. There was a minimal change in the forest area of the Nuwara Eliya owing to the government’s forest preservation policies. The mean temperature of the study area increased by 2.1 °C from 1996 to 2017. The magnitude of mean LST between urban–rural zones also increased from 1.0 °C (1996) to 3.5 °C (2017). The results also showed that mean LST was positively correlated with the increase and decrease of the BL/FL and AL/FL fraction ratios, respectively. The grid-based analysis showed an increasing, positive relationship between mean LST and density of BL. This indicated that BL density had been a crucial element in increasing LST in the study area. The results of this study will be a useful indicator to introduce improved landscape and urban planning in the future to minimize the negative impact of LST on urban sustainability.
Manjula Ranagalage; Yuji Murayama; Dmslb Dissanayake; Matamyo Simwanda. The Impacts of Landscape Changes on Annual Mean Land Surface Temperature in the Tropical Mountain City of Sri Lanka: A Case Study of Nuwara Eliya (1996–2017). Sustainability 2019, 11, 5517 .
AMA StyleManjula Ranagalage, Yuji Murayama, Dmslb Dissanayake, Matamyo Simwanda. The Impacts of Landscape Changes on Annual Mean Land Surface Temperature in the Tropical Mountain City of Sri Lanka: A Case Study of Nuwara Eliya (1996–2017). Sustainability. 2019; 11 (19):5517.
Chicago/Turabian StyleManjula Ranagalage; Yuji Murayama; Dmslb Dissanayake; Matamyo Simwanda. 2019. "The Impacts of Landscape Changes on Annual Mean Land Surface Temperature in the Tropical Mountain City of Sri Lanka: A Case Study of Nuwara Eliya (1996–2017)." Sustainability 11, no. 19: 5517.
The urban heat island (UHI) phenomenon is an important research topic in the scholarly community. There are only few research studies related to the UHI in the Seoul metropolitan area (SMA). Therefore, this study examined the impact of urbanization on the formation of UHI in the SMA as a geospatial study by using Landsat data from 1996, 2006, and 2017. For this purpose, we analyzed the relative variation of land surface temperature (LST) with changes of land use/land cover (LULC) rather than absolute values of LST using gradient, intensity, and directional analyses. It was observed that the impervious surface (IS) has expanded, and the UHI effect was more penetrating in the study area, with considerable loss of other LULC including green surfaces along with the rapid urbanization of the study area. In this study, we divided the IS into persistent IS (PIS) and newly added IS (NAIS). The spatial distribution of the IS, forest surface (FS), PIS, and NAIS was observed based on gradient zones (GZs). The results show that GZ1 recorded a difference of 6.0 °C when compared with the GZ109 in 2017. The results also show that the city center was warmer than the surrounding areas during the period of study. Results reveal that the mean LST has a strong significant positive relationship with a fraction of IS and PIS in 2006 and 2017. On other hand, the mean LST has a strong negative relationship with a fraction of FS and NAIS in the same time points. Relatively low temperatures were recorded in FS and NAIS in both time points. Further, it was proved that the local climate of the SMA and its surroundings had been affected by the UHI effect. Therefore, urban planners of the SMA should seriously consider the issue and plan to mitigate the effect by improving the green surfaces of the city. More greening-oriented concepts are recommended in both horizontal and vertical directions of the SMA, that can be used to control the negative impact associated with UHI. The overall outputs of the study could be used as a proxy indicator for the sustainability of the SMA and its surroundings.
Prabath Priyankara; Manjula Ranagalage; Dmslb Dissanayake; Takehiro Morimoto; Yuji Murayama. Spatial Process of Surface Urban Heat Island in Rapidly Growing Seoul Metropolitan Area for Sustainable Urban Planning Using Landsat Data (1996–2017). Climate 2019, 7, 110 .
AMA StylePrabath Priyankara, Manjula Ranagalage, Dmslb Dissanayake, Takehiro Morimoto, Yuji Murayama. Spatial Process of Surface Urban Heat Island in Rapidly Growing Seoul Metropolitan Area for Sustainable Urban Planning Using Landsat Data (1996–2017). Climate. 2019; 7 (9):110.
Chicago/Turabian StylePrabath Priyankara; Manjula Ranagalage; Dmslb Dissanayake; Takehiro Morimoto; Yuji Murayama. 2019. "Spatial Process of Surface Urban Heat Island in Rapidly Growing Seoul Metropolitan Area for Sustainable Urban Planning Using Landsat Data (1996–2017)." Climate 7, no. 9: 110.
An urban heat island (UHI) is a phenomenon that shows a higher temperature in urban areas compared to surrounding rural areas due to the impact of impervious surface (IS) density, and other anthropogenic activities including changes of land use/land cover (LULC). The purpose of this research is to examine the spatiotemporal land-use/land-cover changes and their impact on the surface UHI (SUHI) in Kandy City, Sri Lanka, using Landsat data and geospatial techniques. LULC classification was made by using a pixel-oriented supervised classification method, and LULC changes were computed by using a cross-cover comparison. The SUHI effect was discussed mainly through the variation of land-surface temperature (LST) over persistent IS and newly added IS. The study showed the dynamics of each LULC and its role in the SUHI. The results showed that IS areas expanded from 529 to 1514 ha (2.3% to 6.7% of the total land area) between 1996 and 2006, and to 5833 ha (23.9% of the total land area) in 2017, with an annual growth rate of 11.1% per year from 1996 to 2006 and 12.2% per year from 2006 to 2017. A gradually declining trend was observed in forest areas. Persistent IS reported the highest mean LST areas compared to newly added IS. The mean LST difference between persistent IS and newly added IS was 1.43 °C over the study period. This is because areas of persistent IS are typically surrounded by IS even in their neighborhoods, whereas areas of newly added IS occur at the edges of the city and are, therefore, cooled by the surrounding nonurban surfaces. This calls for appropriate green-oriented landscape-management methods to mitigate the impact of the SUHI in Kandy City. The findings of the study showed that LULC changes and their effect on the SUHI from 1996 to 2017 made a significant contribution to long records of change dynamics.
Dmslb Dissanayake; Takehiro Morimoto; Manjula Ranagalage; Yuji Murayama. Land-Use/Land-Cover Changes and Their Impact on Surface Urban Heat Islands: Case Study of Kandy City, Sri Lanka. Climate 2019, 7, 99 .
AMA StyleDmslb Dissanayake, Takehiro Morimoto, Manjula Ranagalage, Yuji Murayama. Land-Use/Land-Cover Changes and Their Impact on Surface Urban Heat Islands: Case Study of Kandy City, Sri Lanka. Climate. 2019; 7 (8):99.
Chicago/Turabian StyleDmslb Dissanayake; Takehiro Morimoto; Manjula Ranagalage; Yuji Murayama. 2019. "Land-Use/Land-Cover Changes and Their Impact on Surface Urban Heat Islands: Case Study of Kandy City, Sri Lanka." Climate 7, no. 8: 99.
Forecasting landscape changes is vital for developing and implementing sustainable urban planning. Presently, apart from lowland coastal cities, mountain cities (i.e., hill stations) are also facing the negative impacts of rapid urbanization due to their economic and social importance. However, few studies are addressing urban landscape changes in hill stations in Asia. This study aims to examine and forecast landscape changes in the rapidly urbanizing hill station of Nuwara Eliya, Sri Lanka. Landsat data and geospatial techniques including support vector machines, urban–rural gradient, and statistical analysis were used to map and examine the land use/land cover (LULC) change in Nuwara Eliya during the 1996–2006 and 2006–2017 periods. The multilayer perceptron neural network-Markov model was applied to simulate future LULC changes for 2027 and 2037. The results show that Nuwara Eliya has been directly affected by rapid urban development. During the past 21 years (1996–2017), built-up areas increased by 1791 ha while agricultural land declined by 1919 ha due to augmented urban development pressure. The pressure of urban development on forest land has been relatively low, mainly due to strict conservation government policies. The results further show that the observed landscape changes will continue in a similar pattern in the future, confirming a significant increase and decrease of built-up and agricultural land, respectively, from 2017 to 2037. The changes in agricultural land exhibit a strong negative relationship with the changes in built-up land along the urban–rural gradient (R2 were 0.86 in 1996–2006, and 0.93 in 2006–2017, respectively). The observed LULC changes could negatively affect the production of unique upcountry agricultural products such as exotic vegetables, fruits, cut flowers, and world-famous Ceylon tea. Further, unplanned development could cause several environmental issues. The study is important for understanding future LULC changes and suggesting necessary remedial measures to minimize possible undesirable environmental and socioeconomic impacts.
Manjula Ranagalage; Ruci Wang; M. H. J. P. Gunarathna; Dmslb Dissanayake; Yuji Murayama; Matamyo Simwanda. Spatial Forecasting of the Landscape in Rapidly Urbanizing Hill Stations of South Asia: A Case Study of Nuwara Eliya, Sri Lanka (1996–2037). Remote Sensing 2019, 11, 1743 .
AMA StyleManjula Ranagalage, Ruci Wang, M. H. J. P. Gunarathna, Dmslb Dissanayake, Yuji Murayama, Matamyo Simwanda. Spatial Forecasting of the Landscape in Rapidly Urbanizing Hill Stations of South Asia: A Case Study of Nuwara Eliya, Sri Lanka (1996–2037). Remote Sensing. 2019; 11 (15):1743.
Chicago/Turabian StyleManjula Ranagalage; Ruci Wang; M. H. J. P. Gunarathna; Dmslb Dissanayake; Yuji Murayama; Matamyo Simwanda. 2019. "Spatial Forecasting of the Landscape in Rapidly Urbanizing Hill Stations of South Asia: A Case Study of Nuwara Eliya, Sri Lanka (1996–2037)." Remote Sensing 11, no. 15: 1743.
Urbanization has bloomed across Asia and Africa of late, while two centuries ago, it was confined to developed regions in the largest urban agglomerations. The changing urban landscape can cause irretrievable changes to the biophysical environment, including changes in the spatiotemporal pattern of the land surface temperature (LST). Understanding these variations in the LST will help us introduce appropriate mitigation techniques to overcome negative impacts. The research objective was to assess the impact of landscape structure on the variation in LST in the African region as a geospatial approach in Addis Ababa, Ethiopia from 1986–2016 with fifteen-year intervals. Land use and land cover (LULC) mapping and LST were derived by using pre-processed Landsat data (Level 2). Gradient analysis was computed for the pattern of the LST from the city center to the rural area, while intensity calculation was facilitated to analyze the magnitude of LST. Directional variation of the LST was not covered by the gradient analysis. Hence, multidirectional and multitemporal LST profiles were employed over the orthogonal and diagonal directions. The result illustrated that Addis Ababa had undergone rapid expansion. In 2016, the impervious surface (IS) had dominated 33.8% of the total lands. The IS fraction ratio of the first zone (URZ1) has improved to 66.2%, 83.7%, and 87.5%, and the mean LST of URZ1 has improved to 25.2 °C, 26.6 °C, and 29.6 °C in 1986, 2001, and 2016, respectively. The IS fraction has gradually been declining from the city center to the rural area. The behavior of the LST is not continually aligning with a pattern of IS similar to other cities along the URZs. After the specific URZs (zone 17, 37, and 41 in 1986, 2001, and 2016, respectively), the mean LST shows an increasing trend because of a fraction of bare land. This trend is different from those of other cities even in the tropical regions. The findings of this study are useful for decision makers to introduce sustainable landscape and urban planning to create livable urban environments in Addis Ababa, Ethiopia.
Dmslb Dissanayake; Takehiro Morimoto; Yuji Murayama; Manjula Ranagalage. Impact of Landscape Structure on the Variation of Land Surface Temperature in Sub-Saharan Region: A Case Study of Addis Ababa using Landsat Data (1986–2016). Sustainability 2019, 11, 2257 .
AMA StyleDmslb Dissanayake, Takehiro Morimoto, Yuji Murayama, Manjula Ranagalage. Impact of Landscape Structure on the Variation of Land Surface Temperature in Sub-Saharan Region: A Case Study of Addis Ababa using Landsat Data (1986–2016). Sustainability. 2019; 11 (8):2257.
Chicago/Turabian StyleDmslb Dissanayake; Takehiro Morimoto; Yuji Murayama; Manjula Ranagalage. 2019. "Impact of Landscape Structure on the Variation of Land Surface Temperature in Sub-Saharan Region: A Case Study of Addis Ababa using Landsat Data (1986–2016)." Sustainability 11, no. 8: 2257.
The urban heat island (UHI) and its consequences have become a key research focus of various disciplines because of its negative externalities on urban ecology and the total livability of cities. Identifying spatial variation of the land surface temperature (LST) provides a clear picture to understand the UHI phenomenon, and it will help to introduce appropriate mitigation technique to address the advanced impact of UHI. Hence, the aim of the research is to examine the spatial variation of LST concerning the UHI phenomenon in rapidly urbanizing Lagos City. Four variables were examined to identify the impact of urban surface characteristics and socio-economic activities on LST. The gradient analysis was employed to assess the distribution outline of LST from the city center point to rural areas over the vegetation and built-up areas. Partial least square (PLS) regression analysis was used to assess the correlation and statistically significance of the variables. Landsat data captured in 2002 and 2013 were used as primary data sources and other gridded data, such as PD and FFCOE, were employed. The results of the analyses show that the distribution pattern of the LST in 2002 and 2013 has changed over the study period as results of changing urban surface characteristics (USC) and the influence of socio-economic activities. LST has a strong positive relationship with NDBI and a strong negative relationship with NDVI. The rapid development of Lagos City has been directly affected by conversion more green areas to build up areas over the time, and it has resulted in formulating more surface urban heat island (SUHI). Further, the increasing population and their socio-economic activities including industrialization and infrastructure development have also caused a significant impact on LST changes. We recommend that the results of this research be used as a proxy tool to introduce appropriate landscape and town planning in a sustainable viewpoint to make healthier and livable urban environments in Lagos City, Nigeria
Dmslb Dissanayake; Takehiro Morimoto; Yuji Murayama; Manjula Ranagalage; Hepi H. Handayani. Impact of Urban Surface Characteristics and Socio-Economic Variables on the Spatial Variation of Land Surface Temperature in Lagos City, Nigeria. Sustainability 2018, 11, 25 .
AMA StyleDmslb Dissanayake, Takehiro Morimoto, Yuji Murayama, Manjula Ranagalage, Hepi H. Handayani. Impact of Urban Surface Characteristics and Socio-Economic Variables on the Spatial Variation of Land Surface Temperature in Lagos City, Nigeria. Sustainability. 2018; 11 (1):25.
Chicago/Turabian StyleDmslb Dissanayake; Takehiro Morimoto; Yuji Murayama; Manjula Ranagalage; Hepi H. Handayani. 2018. "Impact of Urban Surface Characteristics and Socio-Economic Variables on the Spatial Variation of Land Surface Temperature in Lagos City, Nigeria." Sustainability 11, no. 1: 25.
Water based soil erosion is a serious socio-economic and environmental problem across the world especially in the tropical region. Assessing the soil erosion quantitatively and spatially provides information to prioritize the soil conservation area in sustainable land management view point. Among the other soil erosion approaches, erosion modeling has been playing a significant role and provides an accurate result in a cost-effective manner. In this study, revised universal soil loss equation (RUSLE) was integrated with remote sensing (RS) and geographic information system (GIS) to analyse the quantitative and spatial distribution of soil erosion across the entire Kotmale watershed which is located in the western part of the central mountain region in Sri Lanka. In the methodology, the parameters of the RUSLE model were estimated using pixel overlay method in ArcGIS software, both spatial data and remote sensing data facilitated with appropriate calibration. From the analysis, the annual soil erosion ranges from 0 to 472 t ha− 1 year− 1 with the mean and standard deviation 9.8 t ha− 1 year− 1 and 15.7 t ha− 1 year− 1 respectively. The mean erosion rate of the model was correlated with ground based data. After the final model was established, conservation priority area was identified by using hot and cold spot analysis. Here “hot spots” shows the area with high soil erosion clustering value, while “cold spot” refers to area with low soil erosion clustering. The soil conservation priority map has been produced and the result shows that approximately 25% represents hot sport. The result would be an aid and sources for soil and water conservation in the Kotmale watershed.
Dmslb Dissanayake; Takehiro Morimoto; Manjula Ranagalage. Accessing the soil erosion rate based on RUSLE model for sustainable land use management: a case study of the Kotmale watershed, Sri Lanka. Modeling Earth Systems and Environment 2018, 5, 291 -306.
AMA StyleDmslb Dissanayake, Takehiro Morimoto, Manjula Ranagalage. Accessing the soil erosion rate based on RUSLE model for sustainable land use management: a case study of the Kotmale watershed, Sri Lanka. Modeling Earth Systems and Environment. 2018; 5 (1):291-306.
Chicago/Turabian StyleDmslb Dissanayake; Takehiro Morimoto; Manjula Ranagalage. 2018. "Accessing the soil erosion rate based on RUSLE model for sustainable land use management: a case study of the Kotmale watershed, Sri Lanka." Modeling Earth Systems and Environment 5, no. 1: 291-306.
Urbanization addresses urban expansion, and it leads conversion of the green space into the built-up area. However, previous studies mainly focused on two-dimensional (2D) urban expansion rather than three-dimensional (3D) growth. Here, the purpose of this study is to examine the urban expansion, including built-up and green space for both horizontal and vertical dimensions using geospatial analysis including remote sensing (RS) and Geographic Information System (GIS) in the sub-Central Business District (CBD) area of Surabaya, Indonesia. The medium resolution remote sensing data for both image and Digital Surface Model (DSM) acquired by Advanced Land-Observing Satellite (ALOS) were applied for time-1 (2010). The orthophoto and DSM derived by LiDAR were used for time-2 (2016). We quantified the built-up and green expansions in 2D (area), which were extracted from land use/land cover (LU/LC) by applying hybrid classification. The built-up and green expansions in 3D (volume) were estimated by generating a surface feature model. The spatial configuration of area expansion was investigated using patch metric, while the volume growth was examined using the volume expansion rate. We got three findings. (1) The built-up and green area had expanded about 11.54% and 95.61%, respectively, from 2010 to 2016. The expansion of green area presented in a notable portion, which was mainly contributed by the conversion of bareland to playground or park. However, the expansion of built-up area was less than the volume expansion of 20.6%. It revealed that built-up growth led to vertical rather than horizontal development. (2) The built-up area expansion tended to scatter configuration, whereas, the green area expansion tended to aggregate in a linear pattern. (3) The ratio of built-up volume expansion to green volume expansion showed a mean of 3.7, indicating that the development of built-up and green volume was imbalanced. The built-up growth presented higher than the green growth, mainly in the areas with more vertical building establishment. The pressing need for higher green volume in the study area was identified in several sites located at surrounding artery and toll roads. Overall, our approach can be applied as a reference in monitoring neighborhood environment through greening programs for sustainable urban development.
Hepi H. Handayani; Yuji Murayama; Manjula Ranagalage; Fei Liu; Dmslb Dissanayake. Geospatial Analysis of Horizontal and Vertical Urban Expansion Using Multi-Spatial Resolution Data: A Case Study of Surabaya, Indonesia. Remote Sensing 2018, 10, 1599 .
AMA StyleHepi H. Handayani, Yuji Murayama, Manjula Ranagalage, Fei Liu, Dmslb Dissanayake. Geospatial Analysis of Horizontal and Vertical Urban Expansion Using Multi-Spatial Resolution Data: A Case Study of Surabaya, Indonesia. Remote Sensing. 2018; 10 (10):1599.
Chicago/Turabian StyleHepi H. Handayani; Yuji Murayama; Manjula Ranagalage; Fei Liu; Dmslb Dissanayake. 2018. "Geospatial Analysis of Horizontal and Vertical Urban Expansion Using Multi-Spatial Resolution Data: A Case Study of Surabaya, Indonesia." Remote Sensing 10, no. 10: 1599.
Presently, the urban heat island (UHI) phenomenon, and its adverse impacts, are becoming major research foci in various interrelated fields due to rapid changes in urban ecological environments. Various cities have been investigated in previous studies, and most of the findings have facilitated the introduction of proper mitigation measures to overcome the negative impact of UHI. At present, most of the mountain cities of the world have undergone rapid urban development, and this has resulted in the increasing surface UHI (SUHI) phenomenon. Hence, this study focuses on quantifying SUHI in Kandy City, the world heritage tropical mountain city of Sri Lanka, using Landsat data (1996 and 2017) based on the mean land surface temperature (LST), the difference between the fraction of impervious surfaces (IS), and the fraction of green space (GS). Additionally, we examined the relationship of LST to the green space/impervious surface fraction ratio (GS/IS fraction ratio) and the magnitude of the GS/IS fraction ratio. The SUHI intensity (SUHII) was calculated based on the temperature difference between main land use/cover categories and the temperature difference between urban-rural zones. We demarcated the rural zone based on the fraction of IS recorded,
Manjula Ranagalage; Dmslb Dissanayake; Yuji Murayama; Xinmin Zhang; Ronald C. Estoque; Enc Perera; Takehiro Morimoto. Quantifying Surface Urban Heat Island Formation in the World Heritage Tropical Mountain City of Sri Lanka. ISPRS International Journal of Geo-Information 2018, 7, 341 .
AMA StyleManjula Ranagalage, Dmslb Dissanayake, Yuji Murayama, Xinmin Zhang, Ronald C. Estoque, Enc Perera, Takehiro Morimoto. Quantifying Surface Urban Heat Island Formation in the World Heritage Tropical Mountain City of Sri Lanka. ISPRS International Journal of Geo-Information. 2018; 7 (9):341.
Chicago/Turabian StyleManjula Ranagalage; Dmslb Dissanayake; Yuji Murayama; Xinmin Zhang; Ronald C. Estoque; Enc Perera; Takehiro Morimoto. 2018. "Quantifying Surface Urban Heat Island Formation in the World Heritage Tropical Mountain City of Sri Lanka." ISPRS International Journal of Geo-Information 7, no. 9: 341.