Dhaka City Water logging Hazards: Area Identification and Vulnerability Assessment through GIS-Remote Sensing Techniques

Abstract Water logging is one of the most detrimental phenomena continuing to burden Dhaka dwellers. This study aims to spatio-temporarily identify the water logging hazard zones within Dhaka Metropolitan area and assess the extent of their water logging susceptibility based on informal settlements, built-up areas and demographical characteristics. The study utilizes integrated Geographic Information System (GIS)-Remote sensing (RS) methods, using Normalized Difference Vegetation Water and Moisture Index, distance buffer zone from drainage streams and built-up distributions to identify waterlogged zones with a temporal extent, incorporating social and infrastructural attributes to evaluate water logging effects. All the indicators were integrated into an overlay GIS method to measure the vulnerability level across Dhaka city areas. The findings reveal that south and south-western parts of Dhaka were more susceptible to water logging hazards. Almost 30–40% of Dhaka belongs to the high/very highly vulnerable zone. Greater number of slum households were observed within high to very high water logging vulnerable zones with approximately 70% of poorly structured households. The built-up areas increased around the northern part of Dhaka across time and exposed to severe water logging issues. A holistic and integrated approach is necessary in future development plans to mitigate the risk of water logging.

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Impact of banning polythene bags on floods of Dhaka City by applying CVM and remote sensing

Proceedings. 2005 IEEE International Geoscience and Remote Sensing Symposium, 2005. IGARSS '05. ◽

10.1109/igarss.2005.1525403 ◽

2005 ◽

Author(s):

S.U. Ahmed ◽

K. Gotoh

Keyword(s):

Remote Sensing ◽

Dhaka City

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Detecting the Cool Island Effect of Urban Parks in Wuhan: A City on Rivers

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18010132 ◽

2020 ◽

Vol 18 (1) ◽

pp. 132

Author(s):

Qijiao Xie ◽

Jing Li

Keyword(s):

Remote Sensing ◽

Negative Impact ◽

Remote Sensing Data ◽

Urban Parks ◽

High Water ◽

Water Bodies ◽

Green Spaces ◽

Heat Island ◽

Island Effect ◽

Urban Heat

As a nature-based solution, development of urban blue-green spaces is widely accepted for mitigating the urban heat island (UHI) effect. It is of great significance to determine the main driving factors of the park cool island (PCI) effect for optimizing park layout and achieving a maximum cooling benefit of urban parks. However, there have been obviously controversial conclusions in previous studies due to varied case contexts. This study was conducted in Wuhan, a city with high water coverage, which has significant differences in context with the previous case cities. The PCI intensity and its correlation with park characteristics were investigated based on remote sensing data. The results indicated that 36 out of 40 urban parks expressed a PCI effect, with a PCI intensity of 0.08~7.29 °C. As expected, larger parks with enough width had stronger PCI intensity. An increased density of hardened elements in a park could significantly weaken PCI effect. Noticeably, in this study, water bodies in a park contributed the most to the PCI effect of urban parks, while the vegetated areas showed a negative impact on the PCI intensity. It implied that in a context with higher water coverage, the cooling effect of vegetation was weakened or even masked by water bodies, due to the interaction effect of different variables on PCI intensity.

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An Assessment of Drought Stress in Tea Estates Using Optical and Thermal Remote Sensing

Remote Sensing ◽

10.3390/rs13142730 ◽

2021 ◽

Vol 13 (14) ◽

pp. 2730

Author(s):

Animesh Chandra Das ◽

Ryozo Noguchi ◽

Tofael Ahamed

Keyword(s):

Remote Sensing ◽

Drought Stress ◽

Land Surface ◽

Climatic Factors ◽

Standardized Precipitation Index ◽

Landsat 8 ◽

Drought Frequency ◽

Moisture Index ◽

Area Index ◽

Drought Period

Drought is one of the detrimental climatic factors that affects the productivity and quality of tea by limiting the growth and development of the plants. The aim of this research was to determine drought stress in tea estates using a remote sensing technique with the standardized precipitation index (SPI). Landsat 8 OLI/TIRS images were processed to measure the land surface temperature (LST) and soil moisture index (SMI). Maps for the normalized difference moisture index (NDMI), normalized difference vegetation index (NDVI), and leaf area index (LAI), as well as yield maps, were developed from Sentinel-2 satellite images. The drought frequency was calculated from the classification of droughts utilizing the SPI. The results of this study show that the drought frequency for the Sylhet station was 38.46% for near-normal, 35.90% for normal, and 25.64% for moderately dry months. In contrast, the Sreemangal station demonstrated frequencies of 28.21%, 41.02%, and 30.77% for near-normal, normal, and moderately dry months, respectively. The correlation coefficients between the SMI and NDMI were 0.84, 0.77, and 0.79 for the drought periods of 2018–2019, 2019–2020 and 2020–2021, respectively, indicating a strong relationship between soil and plant canopy moisture. The results of yield prediction with respect to drought stress in tea estates demonstrate that 61%, 60%, and 60% of estates in the study area had lower yields than the actual yield during the drought period, which accounted for 7.72%, 11.92%, and 12.52% yield losses in 2018, 2019, and 2020, respectively. This research suggests that satellite remote sensing with the SPI could be a valuable tool for land use planners, policy makers, and scientists to measure drought stress in tea estates.

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Quantification of the Environmental Impacts of Highway Construction Using Remote Sensing Approach

Remote Sensing ◽

10.3390/rs13071340 ◽

2021 ◽

Vol 13 (7) ◽

pp. 1340

Author(s):

Shuailong Feng ◽

Shuguang Liu ◽

Lei Jing ◽

Yu Zhu ◽

Wende Yan ◽

...

Keyword(s):

Remote Sensing ◽

Environmental Impacts ◽

Land Surface ◽

Vegetation Index ◽

Highway Construction ◽

Temporal Changes ◽

Moisture Index ◽

Buffer Zones ◽

Wide Range ◽

Spatial And Temporal Changes

Highways provide key social and economic functions but generate a wide range of environmental consequences that are poorly quantified and understood. Here, we developed a before–during–after control-impact remote sensing (BDACI-RS) approach to quantify the spatial and temporal changes of environmental impacts during and after the construction of the Wujing Highway in China using three buffer zones (0–100 m, 100–500 m, and 500–1000 m). Results showed that land cover composition experienced large changes in the 0–100 m and 100–500 m buffers while that in the 500–1000 m buffer was relatively stable. Vegetation and moisture conditions, indicated by the normalized difference vegetation index (NDVI) and the normalized difference moisture index (NDMI), respectively, demonstrated obvious degradation–recovery trends in the 0–100 m and 100–500 m buffers, while land surface temperature (LST) experienced a progressive increase. The maximal relative changes as annual means of NDVI, NDMI, and LST were about −40%, −60%, and 12%, respectively, in the 0–100m buffer. Although the mean values of NDVI, NDMI, and LST in the 500–1000 m buffer remained relatively stable during the study period, their spatial variabilities increased significantly after highway construction. An integrated environment quality index (EQI) showed that the environmental impact of the highway manifested the most in its close proximity and faded away with distance. Our results showed that the effect distance of the highway was at least 1000 m, demonstrated from the spatial changes of the indicators (both mean and spatial variability). The approach proposed in this study can be readily applied to other regions to quantify the spatial and temporal changes of disturbances of highway systems and subsequent recovery.

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The responses of vegetation water content (EWT) and assessment of drought monitoring along a coastal region using remote sensing

GIScience & Remote Sensing ◽

10.1080/15481603.2014.882564 ◽

2014 ◽

Vol 51 (1) ◽

pp. 1-16 ◽

Cited By ~ 13

Author(s):

Zhiqiang Gao ◽

Qiuxian Wang ◽

Xiaoming Cao ◽

Wei Gao

Keyword(s):

Remote Sensing ◽

Water Content ◽

Coastal Region ◽

Drought Monitoring ◽

Vegetation Water Content ◽

Vegetation Water

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Assessing the livelihood of slum dwellers in Dhaka city

Journal of the Bangladesh Agricultural University ◽

10.3329/jbau.v7i2.4749 ◽

1970 ◽

Vol 7 (2) ◽

pp. 373-380 ◽

Cited By ~ 5

Author(s):

MS Alamgir ◽

MA Jabbar ◽

MS Islam

Keyword(s):

Financial Services ◽

Integrated Approach ◽

Public Affairs ◽

Urban Migration ◽

Dhaka City ◽

Economic Reason ◽

Slum Dwellers ◽

Rural Urban Migration ◽

Micro Credit ◽

Slum Areas

The present study was an attempt to determine the factors affecting the livelihood of the socioeconomic improvement of migrants and to analyze the causes of rural-urban migration in slum areas. Slum areas have no available formal education facilities and slum people were found to be engaged in rickshaw pulling, day labourer, petty business, small job services etc. Analysis showed that migration and taking in micro credit were beneficial for the slum dwellers. Receiving and utilizing micro credit income level, consumption, expenditure and socio-economic status of the slum dwellers improved to some extent. Due to participation of slum dwellers in NGOs, their economic, social and decision making improved substantially. Credit disbursement through NGOs with integrated approach could bring positive changes in the life of poor slum women as well as their community. Findings showed that Fifty six per cent people migrated to Dhaka city for economic reason. Factors of migration had a significant contribution of rural urban migration and also significant livelihood improvement has taken place due to micro credit. At the individual level, the women were benefited in terms of mobility and skill, self confidence, widening of interests, access to financial services, build own savings, competence in public affairs and status at home and in the community that lead a better awareness for enhancing women's empowerment. However, there is a need for proper training for sustainable result in the long run. Keywords: Migration; Livelihood; Micro credit DOI: 10.3329/jbau.v7i2.4750 J. Bangladesh Agril. Univ. 7(2): 373-380, 2009

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Basic models of human-centrist, polyspiral, sustainable development of Ukraine

Problems of Innovation and Investment Development ◽

10.33813/2224-1213.24.2021.3 ◽

2021 ◽

pp. 37-45

Author(s):

Valery Borzunov

Keyword(s):

Sustainable Development ◽

Buffer Zone ◽

Integrated Approach ◽

Theory And Practice ◽

External Control ◽

Developed Country ◽

The Future ◽

The Status ◽

Scientific Results ◽

Definition Of

Subject of study. A set of relations that are formed in the process of determining models of sustainable development of Ukraine and the principles of designing the economy of the future. Purpose of the article: research of the main directions of sustainable development of Ukraine and the formation of principles of strategy. Research methodology. Scientific novelty of the work, the theoretical and methodological basis of the research is the system of both general scientific and special methods of scientific knowledge, the fundamental provisions of modern economic theory and practice. The proposed methodology of a system-integrated approach to the formation of basic models of man-centered, multispiral, sustainable development of Ukraine. As integrity in the organic unity of the prevailing prerequisites for the formation of the principles of strategizing. Scientific novelty lies in the definition of models for sustainable development of Ukraine and the principles of designing the economy of the future. Results of the work – the applied use of scientific results of improved approaches for the development and implementation of a strategy for human- centered, polyspiral, sustainable development is proposed. Conclusions. For 30 years of independence, Ukraine has turned from an industrially developed country into a backward and poorest country in Europe with an economy of lagging growth, the status of a «buffer zone» of geopolitical conflict on its territory and external control. To maintain sovereignty, ensure the country's competitiveness in the context of the transition to new technological paradigms and the quality of life of the population, at least at the average level for the EU countries, Ukraine needs to change course, develop and implement the «Strategy of human-centrist, multi-spiral, sustainable development».

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