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Urban green space is one of the most essential components in contributing to ecological balance and environmental sustainability. Due to rapid urbanization in the last few decades, massive reduction of urban vegetation cover (VC) has increased the land surface temperature (LST) and hampered the environmental sustainability. This study aims to identify the VC cover loss on LST increase in Rajshahi City Corporation (RCC) area using geospatial techniques. The study established the relationship between VC loss and LST increase using transformation analysis and micro-level directional mapping in ArcGIS 10.6 software. Multi-temporal Landsat TM/OLI satellite images were used for the years 1990, 2000, 2010 and 2020, to classify land use/land cover (LULC) classes, the transition between VC and urban area (UA), directional distribution of UA and VC, and variation of ward wise LST distribution due to VC loss in the study area. The maximum likelihood supervised classification algorithm was used to.....

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The different peak discharge value estimated in the rational method (RM) model is caused by the various methods used to determine the runoff coefficient (C) parameter. The C value can be defined as the total amount of rainfall generated to become the runoff. Various studies have been conducted to produce C values that differ from one to another. For example, the C values suggested by the Manual of Storm Water Management (MSMA) and the American Society of Civil Engineers (ASCE) differed. To estimate C values, land use classification is confusing, unorganized, and not uniform, and therefore, the application of suggested C value is still doubtful to be applied in Malaysia. Thus, this research focused on estimating the C value based on the land use classification for urban areas in Penang using a rainfall simulator. The runoff coefficient will be generated from various surface types at a plot scale representing urban land use. The result obtained shows that the C values were 0.79?0.89 (asp.....

446 hits

Human activity has boosted carbon dioxide emissions, causing temperatures to rise. The average temperature on Earth is roughly 15��C, but it has been much higher and lower in the past. There are natural climatic changes, but experts say temperatures are already rising faster than at any other period in history. Unplanned urbanization can sometimes backfire, causing negative consequences that harm the economy and contribute to environmental damages, especially in developing countries like Bangladesh. Because of the strong association between land use/land cover and land surface temperature (LST), the study attempted to analyze and estimate LULC and seasonal (both summer and winter) LSTs using Landsat satellite images at 5-year intervals from 1995 to 2020. Later, the study forecasted both LULC and seasonal LSTs for 2030 and 2040 using cellular automata (CA) and artificial neural network (ANN) algorithms for Rajshahi district. As supporting parameters for determining the magnitude of .....

399 hits

Forests are vital in combating climate change by storing and sequestrating CO2 from the atmosphere. Measuring the influence of land use/land cover (LULC) changes on the capacity of carbon storage (CS) within forest ecosystems presents a significant challenge. This study employs remote sensing techniques to examine the changes in spatiotemporal patterns of CS in the Chittagong Hill Tracts (CHT), resulting from LULC alterations between 1996 and 2021. LULC change patterns were identified for six different years utilizing the Google Earth Engine (GEE). The Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) model was combined with GEE to evaluate the changing patterns of CS. The study discovered that the CHT region experienced a loss of 21.65 106 Mg of CS, owing to a 21% reduction in vegetation cover (2862.85 km^2) during the study period. The central city area (Chittagong) accounted for the most significant loss of CS (7.99 106 Mg), while the suburban areas of Khagrachari (0.....

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The Federal University of Technology at Akure (FUTA) in Nigeria is experiencing ongoing development that is leading to the replacement of agricultural and forestry land cover types. This study aimed to assess and predict changes in land use/land cover (LULC) types and their impact on crop characteristics in 17 plots of FUTA from 1991 to 2031. Crop characteristics were evaluated using the normalized difference vegetation index (NDVI), normalized difference water index (NDWI), normalized difference moisture index (NDMI), vegetation condition index (VCI), watershed delineation, and spectral characteristics using Landsat imageries. The land change modeler in TerraSet software was used to predict future LULC scenarios. Results showed an increase in built-up areas (15%) and bare land areas (14%), but a reduction of 19% in light vegetation cover from 1991 to 2021. The predicted LULC map illustrated a decrease in light vegetation area (11%) and an increase in built-up area (19%) from 1991 to 2.....

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Urbanization significantly accelerates the replacement of natural land-use and land-cover (LULC) classes, which can raise the temperature and diminish thermal comfort zone (TCZ), potentially negatively affecting the environment and human health. This study assesses and predicts the impacts of LULC change on directional shrinkage of the TCZ in Kuwait, using Landsat images and cellular automata (CA) and artificial neural networks (ANN) algorithms from 1991 to 2031. The analysis revealed a rapid urban expansion (40%) in south-east (SE), north-east (NE), and north-west (NW) directions and shrinkage of TCZ (25% area with a very uncomfortable thermal condition) in NNW and SW directions, from 1991 to 2021. The predicted scenario showed an increase in urban areas from 44% (2021) to 47% (2026) and 52% (2031). In contrast, very uncomfortable TCZ (35% in 2026 and 40% in 2031) was found concentrated around urban areas and bare land toward NNE and NNW directions. The study proposes effective and su.....

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Liners are provided under engineering landfill sites to block the downflow of leachates and their noxious components to minimize pollution in the underlying aquifers or neighboring water bodies. Compacted clays are widely employed as suitable materials for constructing landfill liners because of their low hydraulic conductivity, balanced swelling potentials, and appropriate compressive strength. However, the quality has to be improved if the locally available soil does not meet the minimum standards for constructing liner materials. Including bentonite dosage with local soil can show better stability and strengthened cohesion bonds between molecules. This paper aims at a recent study on specific geotechnical properties of bentonite amended local Khulna clay soil intended to be used as a liner material. Bentonite in varying proportions (e.g., 5%, 10%, 15%, and 20%) was mixed with local soil, and specific tests (e.g., compaction tests, consistency tests, hydraulic conductivity tests, fre.....

75 hits

Assessment of trends and variability of atmospheric particles can help set the target for pollution reduction, robust air-pollution and climate change policy decision-making, and clean air. This study investigated the recent trends and variability of Particulate Matter 2.5 (PM2.5) concentrations led by meteorological factors in fifteen major South Asian cities. It comprehensively assessed the influence of climatic factors through multiple statistical and time-frequency models. Trends were identified using the Mann-Kendal Test and innovative trend analysis methods. This study found the most critical air quality condition in Lahore (105.43 ?g/m3), safe condition in Ho Chi Minh City (25.97 ?g/m3), and most of the cities experience unhealthy to very unhealthy air conditions during winter. PM2.5 levels exhibited ascending trends in Dhaka, Jakarta, Lahore, Karachi, and Islamabad, while descending trends in Delhi, Mumbai, Hyderabad, Kolkata, Chennai, Kathmandu, Rangoon, Hanoi, Vientiane, and .....

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