Impervious Surface Research Articles

Planning eco-sensitive zones for promoting tree diversity and ecosystem services in urban academic landscapes: a case study from the North-western Indo-Gangetic plain

ABSTRACT Urban academic greenspaces provide a protective environment for the conservation of plants and animals and ecological health benefits to human beings. Several anthropogenic activities and landscape practices lead to patches of natural and built-up areas; therefore, a better understanding of campus tree diversity and ecosystem services among natural and built-up areas may help in biodiversity management. Considering this, we assessed how landscape heterogenicity (i.e. the proportion of natural and built-up/paved surface area) and planning principles influence tree density and diversity patterns in three zones (buffer zone: natural/remnant woodland; transition zone: mixed open grassland and woody plantation; core zone: paved/built-up, grassland, and scattered woody plantation) in the Indian Institute of Science Education and Research (IISER) Mohali campus (Punjab) India. We found a total of 1,993 trees belonging to sixty-eight species, mostly native flora. We found that landscape planning principles significantly influenced tree diversity patterns, with the highest tree diversity in the B3 buffer zone (H: 2.9, PIE: 0.9), which integrated elements of the original landscape and new plantations to optimise ecological value and the lowest diversity in the B2 buffer zone (i.e. H: 0.4; PIE: 0.2) with a monoculture plantation of exotic agroforestry species. We also observed that tree density was negatively influenced by impervious surface area (r = -0.68, p < 0.05) in the core zones and by the plantation of exotic species in the natural areas. The campus diversity supports birds of different feeding guilds (insectivore: 41%, omnivore: 25%, carnivore: 25%, frugivore/nectarivore: 13%, graminivore: 4%, and piscivore: 2%). Additionally, academic buildings planned with high canopy cover and density (45% and 95 ha−1) had reduced the wall temperatures of academic buildings from 12°C to 6°C compared to neighbouring buildings without tree cover. This highlighted the importance of maintaining tree diversity in urban academic institutions to promote urban sustainability.

A Study of the Drainage Capacity, Flood Risks and Mitigation Measures for Selected Areas in Guyana’s Coastal and Riverine Regions: Williamsburg- Hampshire, Kilcoy-Chesney and Mabaruma-Kumaka-Barabina

This research investigates the drainage challenges and flood risks in three areas of Guyana: Williamsburg-Hampshire, Kilcoy-Chesney, and Mabaruma-Kumaka-Barabina. These drainage areas are characterised by low-lying terrain, proximity to waterways, and inadequate drainage infrastructure. The study identifies how these factors lead to frequent and sometimes costly flooding, especially during periods of peak rainfall and high tides that prevent the opening of drainage sluices. Using rainfall and runoff data, with the analysis of drainage coefficients and discharge capacities, the study examines the existing drainage systems in these regions. It highlights the inefficiencies of undersized drainage structures, inadequate maintenance, and the growing pressure from urbanisation, which has led to the expansion of impervious surfaces, thus increasing runoff. In the case of Mabaruma-Kumaka-Barabina, under- maintained sluices, narrow bridge culverts, and low earthen dams exacerbate the area’s flood vulnerabilities. To address these issues, the study recommends several key interventions. These include upgrading drainage infrastructure by widening internal drains, replacing narrow culverts, installing additional sluices, and using modern technologies like automated pumps and self-actuated sluices. The construction of higher, vegetated embankments and raising the earthen river dams are also recommended to prevent erosion and overtopping during high tides. Monitoring water levels and rainfall data regularly is proposed to inform drainage maintenance and flood prevention efforts. The findings underscore the need for public-private partnerships to maintain drainage systems while engaging the community in flood risk mitigation. By implementing these recommendations, these regions can better manage water flow, reduce the impact of flooding, and improve the quality of life for residents, particularly as climate change continues to pose greater challenges for water management in Guyana.

Combined effects of urbanization and climate variability on water and carbon balances in a rice paddy-dominated basin in southern China

Abstract Urbanization is known to elevate storm runoff, but how it influences carbon cycle and ecosystem productivity through altering the evapotranspiration (ET) process is less clear. We examined the combined effects of urbanization including change in impervious surface area (ISA) and climate variability on the water and carbon balances of the Qinhuai River Basin (QRB) over 2001–2018. QRB represents a typical rice paddy-dominated region that experienced rapid urbanization in southern China. We improved a monthly scale water supply stress index ecosystem service model by integrating local eddy flux measurements and high-resolution remote sensing data. We found a significant downward trend in both ET (−4.6 mm yr−1, p &lt; 0.05) and gross primary productivity (GPP) (−10.4 gC m−2 yr−1, p &lt; 0.05) but a significant upward trend in water yield (Q) (+28.6 mm yr−1, p &lt; 0.05). These ecosystem function changes coincided with a 96% increase in urban areas, 1.9-fold increase in ISA, and a 37% reduction in rice paddy fields. The mean annual watershed GPP decreased from 1048 gC m−2 to 998 gC m−2 while the annual Q increased from 284 mm to 669 mm from 2001 to 2018. Scenario modeling experiments suggested that the negative impacts of loss of rice paddy fields and increase in ISA on ET and GPP overwhelmed the positive impacts of climate warming. The reduction in GPP and increase in Q were largely attributed to the increases in ISA, not necessarily due to changes in land use types (e.g. urban area). The expansion of urban area, increase in ISA and reduction in leaf area index, and increase in precipitation explained the increase in Q. Our research offers insight about the interactions of carbon and water cycles through the critical ET processes under a changing climate and land surface characteristics at a watershed level. Our modeling tool and analysis provides land managers and policy makers information for designing effective ‘Urban Nature-based Solutions’ to mitigate the negative environmental effects of urbanization on carbon and water resources.

A Parameter Optimized Method for InVEST Model in Sub-Pixel Scale Integrating Machine Learning Algorithm and Vegetation–Impervious Surface–Soil Model

The InVEST model, with its ability to perform spatial visualization and quantification, is an important tool for mapping ecosystem services. However, the spatial accuracy and simulating performance of the model are deeply influenced by the land use parameter, which often relies on the accuracy of land use/cover data. To address this issue, we propose a novel method for optimizing the land use parameter of the InVEST model based on the vegetation–impervious surface–soil (V–I–S) model and a machine learning algorithm. The optimized model is called Sub-InVEST, and it improves the performance of assessing ecosystem services on a sub-pixel scale. The conceptual steps are (i) extracting the V–I–S fraction of remote sensing images based on the spectral unmixing method; (ii) determining the mapping relationship of the V–I–S fraction between land use/cover type using a machine learning algorithm and field observation data; (iii) inputting the V–I–S fraction into the original model instead of the land use/cover parameter of the InVEST model. To evaluate the performance and spatial accuracy of the Sub-InVEST model, we employed the habitat quality module of InVEST and multi-source remote sensing data, which were applied to acquire Sub-InVEST and estimate the habitat quality of central Guangzhou city from 2000 to 2020 with the help of the LSMA and ISODATA methods. The experimental results showed that the Sub-InVEST model is robust in assessing ecosystem services in sets of complex ground scenes. The spatial distribution of the habitat quality of both models revealed a consistent increasing trend from the southwest to the northeast. Meanwhile, linear regression analyses observed a robust correlation and consistent linear trends, with R2 values of 0.41, 0.35, 0.42, 0.39, and 0.47 for the years 2000, 2005, 2010, 2015, and 2020, respectively. Compared with the original model, Sub-InVEST had a more favorable performance in estimating habitat quality in central Guangzhou. The spatial depictions and numerical distribution of the results of the Sub-InVSET model manifest greater detail and better concordance with remote sensing imagery and show a more seamless density curve and a substantially enhanced probability distribution across interval ranges.

A blue–green ratio of urban wetlands as an ecosystem health indicator: the case of urban sprawl in Nagpur, India

ABSTRACT Rampant urban sprawl has affected the structure and function of existing urban green and blue spaces, exposing developing cities to unexpected disaster events. Drawing on a mixture of secondary information supported by GIS and field-based studies, we assessed the impact of growing impervious surfaces on the dynamic zones of urban wetlands in Nagpur, India. We compared decadal data (2000-2020) to understand the pattern of wetland loss and its drivers in the region. Our findings reveal a significant loss of wetland structure and area over the past two decades, raising alarming concerns regarding ecological and economic repercussions. To address these issues, we propose a blue–green buffer-based assessment approach that incorporates local knowledge and observations along with proactive monitoring of ecosystem health. Our study highlights the urgency of reducing the spatial complexity of landscape patches, restoring wetland buffers, declaring wetland buffers as no-go zones, and promoting corridor connectivity to urban wetlands to improve urban blue infrastructure health. Multi-sectoral and stakeholder cooperation, involvement, and strict enforcement of the Wetland Rules (2017) by local governing bodies can help build urban resilience by protecting urban blue–green infrastructure.

Analyzing Monterrey blue/green infrastructure for the mitigation of heat islands using Earth Observation and WUDAPT method

Abstract. The Metropolitan Area of Monterrey has grown excessively along with its population in recent decades, resulting in an urban area with problems of distribution of spaces and services. In addition to this, factors such as pollution resulting from industrial activities and the reduction of green areas are related to the increase in temperatures in the area and the creation of urban heat islands, which are mitigated by the cooling action provided by the green/blue infrastructure of urban rivers. Because the rivers in the study area do not have a continuous channel throughout the year and the water supply problems that have recently worsened due to the drought in the north of the country, the riparian vegetation of its 3 rivers (Pesqueria, Santa Catarina and La Silla) plays a crucial role in reducing temperatures by acting as a natural heat sink, so its conservation and restoration is essential. In this research, the influence of rapid urbanization on the deterioration of rivers during 2003, 2013 and 2021 was evaluated using Google Earth Engine and the WUDAPT scheme for local climatic zones, finding that there is a correspondence between local climatic zones and fluctuations in temperature. The results obtained over a period of approximately two decades indicate that natural climate zones register lower temperatures compared to impervious surfaces, and that there is also considerable variation between areas with dense green/blue infrastructure and natural covers with little or no vegetation, since the latter have temperatures similar to those of the built classes.

The Impact of Climate Change and Urbanization on Compound Flood Risks in Coastal Areas: A Comprehensive Review of Methods

Many cities worldwide are increasingly threatened by compound floods resulting from the interaction of multiple flood drivers. Simultaneously, rapid urbanization in coastal areas, which increases the proportion of impervious surfaces, has made the mechanisms and simulation methods of compound flood disasters more complex. This study employs a comprehensive literature review to analyze 64 articles on compound flood risk under climate change from the Web of Science Core Collection from 2014 to 2024. The review identifies methods for quantifying the impact of climate change factors such as sea level rise, storm surges, and extreme rainfall, as well as urbanization factors like land subsidence, impervious surfaces, and drainage systems on compound floods. Four commonly used quantitative methods for studying compound floods are discussed: statistical models, numerical models, machine learning models, and coupled models. Due to the complex structure and high computational demand of three-dimensional joint probability statistical models, along with the increasing number of flood drivers complicating the grid interfaces and frameworks for coupling different numerical models, most current research focuses on the superposition of two disaster-causing factors. The joint impact of three or more climate change-driving factors on compound flood disasters is emerging as a significant future research trend. Furthermore, urbanization factors are often overlooked in compound flood studies and should be considered when establishing models. Future research should focus on exploring coupled numerical models, statistical models, and machine learning models to better simulate, predict, and understand the mechanisms, evolution processes, and disaster ranges of compound floods under climate change.

The Role of Subsurface Changes and Environmental Factors in Shaping Urban Heat Islands in Southern Xinjiang

The urban heat island (UHI) effect is one of the most prominent surface climate changes driven by human activities. This study examines the UHI characteristics and influencing factors in the Southern Xinjiang urban agglomeration using MODIS satellite data combined with observational datasets. Our results reveal a significant increase in impervious surfaces in the region between 1995 and 2015, with the most rapid expansion occurring from 2010 to 2015. This urban expansion is the primary driver of changes in UHI intensity. The analysis from 2000 to 2015 shows substantial spatial variation in UHI effects across cities. Hotan recorded the highest annual average daytime UHI intensity of 3.7 °C, while Aksu exhibited the lowest at approximately 1.6 °C. Daytime UHI intensity generally increased during the study period, with the highest intensities observed in the summer. However, nighttime UHI trends varied across cities, with most showing an increase in intensity. Temperature, precipitation, and aerosol optical depth (AOD) were identified as the main factors influencing annual average daytime UHI intensity, while PM10 concentration showed a weak and inconsistent correlation with UHI intensity, varying by city and season.

Bat microfilariae in the cityscape: a transmission tale between bats, mites, and bat flies

Litomosoides includes filarial nematodes capable of infecting various vertebrate species. While Litomosoides has been extensively studied in rodents, research on its association with bats remains limited. The transmission dynamics of this parasite are complex, involving moving between different invertebrate hosts before reaching the final host. Most investigations concerning microfilariae have concentrated on their morphological characteristics, with scant attention paid to ecological aspects, particularly in human-altered landscapes. This study represents the first known documentation of Litomosoides in bats within an urban environment. It investigates their response to urbanization in their interaction with the synanthropic bat Artibeus jamaicensis and its ectoparasites. The objective was to explore the influence of urban landscapes on Litomosoides prevalence in synanthropic hosts. Blood samples were collected along urban-rural gradients, and parasite presence was confirmed through direct observation in blood smears and PCR. Phylogenetic analysis based on the mitochondrial cytochrome c oxidase subunit 1 gene (COX1), which exhibited robust support values, indicates that the microfilaria found in A. jamaicensis is closely related to Litomosoides chandleri. However, it also suggests the possibility of an unidentified, and therefore potentially new, species within the genus Litomosoides. Additionally, Litomosoides DNA was detected in Periglischrus iheringi (Acari: Spinturnicidae) and in the bat fly Trichobius intermedius collected from the bat. The parasite sequences obtained from these three interacting species exhibited a genetic distance as low as 0.002. The highest prevalences were recorded in forested areas (28.6%) compared with urban areas (21.2%). However, within the urban landscape, prevalence varied from 3.8% to 21.2%, being highest in densely built-up areas. Analysis of the urban landscape suggested that the prevalence of Litomosoides in A. jamaicensis is the result of a multifactorial and synergistic process involving ectoparasite load, host abundance, and the extent of impervious surfaces (NDBI).

Modeling Urban Expansion and Its Impacts on Carbon Storage Through Integrative Scenario Analysis for Sustainable Development in the Changchun-Jilin-Tumen Region

The Changchun-Jilin-Tumen (CJT) region in Northeast China is a key economic hub and a strategic gateway for China's integration into Northeast Asia, playing a crucial role in the Belt and Road Initiative. However, rapid urbanization in this region has precipitated substantial environmental challenges, particularly the degradation of carbon storage services (CSS) due to the expansion of impervious surface areas (ISA). This study employs multi-source remote sensing data, advanced geospatial analysis, and scenario-based decision-making technologies to evaluate the impacts of ISA expansion on CSS from 2000 to 2035 using the PLUS and InVEST models. The results reveal significant losses in CSS, with a net decrease of 8.10 × 10⁶ tons of carbon projected by 2022. Under the Natural Development scenario, these losses could escalate to 15.32 × 10⁶ tons by 2035. Conversely, the Ecological Protection and High-Quality Development scenarios suggest that strategic interventions could mitigate these losses, potentially leading to CSS gains of up to 3.42 × 10⁶ tons in the Ecological Protection scenario. This study highlights the pressing need to integrate ecological considerations into urban planning to balance development with environmental sustainability. The findings provide essential guidance for policymakers aiming to align urban growth with carbon neutrality targets, particularly in the context of global climate commitments and the increasing imperative for sustainable urban development.

Analyzing urban water metabolism of Adama city using water mass balance method for advancing water sensitive interventions

Urban water metabolism focuses on measuring water inflows and outflows within a defined urban system. As an emerging concept, it provides valuable understandings into water flow dynamics, supporting evidence-based decision-making. One approach to quantify these flows is the urban water mass balance method, which accounts for both human-induced and natural water resources. By equating these flows, it identifies whether water movement within the system is linear or circular. The primary goal of water mass balance analysis is to assess how closely a city aligns with water-sensitive management approaches. However, urban metabolism studies are rare in developing countries, where cities often lack the experience to estimate water inflows and outflows for informed water-sensitive interventions. This study addresses this gap by analyzing Adama city in Ethiopia using the water mass balance method to measure its water metabolism. The result revealed that the city faces a negative water balance with outflows exceeding inflows by 46.89 million cubic meters annually. The results indicated that Adama’s water flow follows a linear “take-make-use-dispose” model. The imbalance in Adama’s water cycle is driven by urbanization, impervious surfaces, and climate change, which increase runoff and evaporation. The study found that 61.3% of the city’s water comes from a centralized system, with 90% sourced from distant rivers through a telecoupling system. In the city, inadequate water harvesting, high population density and intensive water use are worsening water scarcity. Urban water metabolism indicators reveal significant losses and indicating the need for water conservation efforts. Despite the reliance on centralized systems, the study identifies strong potential for decentralized solutions and alternative water harvesting. To tackle these challenges, the research recommends adopting water-sensitive strategies such as low-impact development, sustainable urban drainage systems, and water-sensitive urban design and planning. These approaches can reduce the negative effects of urbanization, mitigate urban water scarcity risks and improve water management through water sensitive management approach. The study also emphasizes the need for collaborative learning, community involvement, and innovative technologies, supported by legal frameworks to ensure effective water wise interventions. Shifting toward circular water management and decentralized water systems will boost Adama’s resilience and promote sustainable water resource management, making the city more internally self-sufficient.

Case Study Analysis on the Flood Mitigation Effects of Improving a Drainage System Using Low Impact Development Techniques

Low-impact development (LID) techniques aim to minimize the hydrological and environmental impacts associated with watershed development by preserving the natural state as much as possible, reducing impervious surfaces, managing stormwater on a small scale at the point of generation, and promoting decentralized stormwater management. In this study, the flood reduction effects of LID techniques were analyzed using PCSWMM by comparing traditional development methods in the Songsan Green City development project. In this process, the LID technique considers nonstructural methods of diversifying drainage directions and structural methods of introducing vegetated swales to improve the drainage system. The results showed that the LID approach, introduced to improve the drainage system, had a significant effect on reducing floods and inundation compared to traditional development methods. The results of this study suggest the potential of using LID techniques in structural and nonstructural approaches to improve urban flooding and inundation problems.

Improving the water quality in the Zandvlei Estuary, Cape Town, by retrofitting sustainable drainage systems in the Diep River catchment

The Zandvlei Estuary is the only functioning estuary along the False Bay coastline of Cape Town and is therefore of extreme local ecological importance. The most significant problems are eutrophication and siltation caused by the increased total inorganic nitrogen (TIN) and soluble ready phosphorus (SRP) levels due to urban development and the associated increased impervious surface area in the catchment that drains into it. In South Africa, stormwater drainage systems conventionally channel everything they collect into receiving water bodies without significant treatment. Sustainable drainage systems (SuDS) provide an alternative approach to managing stormwater runoff. They are designed to manage both stormwater quality and quantity while potentially improving biodiversity and amenity. This project modelled the potential improvement in the quality of the water entering Zandvlei Estuary resulting from the implementation of selected SuDS control measures in Zandvlei’s Diep River catchment using the software program, PCSWMM. SRP, TIN, total phosphorus (TP) and total suspended solids (TSS) were selected as pollutant indicators. Treatment trains that included a large, constructed wetland at the bottom of the catchment will likely provide the greatest improvements to the water quality entering Zandvlei – potentially reducing SRP, TIN, TP and TSS by approximately 59%, 53%, 53%, and 66%, respectively – as well as potentially reducing the runoff by 48%.

Evaluating Factors Affecting Flood Susceptibility in the Yangtze River Delta Using Machine Learning Methods

AbstractFloods are widespread and dangerous natural hazards worldwide. It is essential to grasp the causes of floods to mitigate their severe effects on people and society. The key drivers of flood susceptibility in rapidly urbanizing areas can vary depending on the specific context and require further investigation. This research developed an index system comprising 10 indicators associated with factors and environments that lead to disasters, and used machine learning methods to assess flood susceptibility. The core urban area of the Yangtze River Delta served as a case study. Four scenarios depicting separate and combined effects of climate change and human activity were evaluated using data from various periods, to measure the spatial variability in flood susceptibility. The findings demonstrate that the extreme gradient boosting model outperformed the decision tree, support vector machine, and stacked models in evaluating flood susceptibility. Both climate change and human activity were found to act as catalysts for flooding in the region. Areas with increasing susceptibility were mainly distributed to the northwest and southeast of Taihu Lake. Areas with increased flood susceptibility caused by climate change were significantly larger than those caused by human activity, indicating that climate change was the dominant factor influencing flood susceptibility in the region. By comparing the relationship between the indicators and flood susceptibility, the rising intensity and frequency of extreme precipitation as well as an increase in impervious surface areas were identified as important reasons of heightened flood susceptibility in the Yangtze River Delta region. This study emphasized the significance of formulating adaptive strategies to enhance flood control capabilities to cope with the changing environment.

Ecological effects of land use and land cover change in the typical ecological functional zones of Egypt

Evaluation the value of ecosystem services can provide crucial reference for formulating ecological protection plans and making informed management decision. This study utilized Landsat remote sensing images as the data source and employed land-use transfer chains and land use transfer matrix methods to compare the ecological effects of land use and land cover change(LUCC) in the two typical ecological functional zones of Egypt, one area isthe northern region of Egypt with the Priority function of Economic Development, another area is the Nasser Reservoir area with the priority function of water conservation. The key findings are as follows: (1)The northern region of Egypt and the Nasser Reservoir exhibited different trends across the ecological functional zones.From 1985 to 2020, the northern region of Egypt is characterized by an increase in arable land and impervious surface,the Nasser Reservoir area is distinguished by the expansion of water and a reduction in sand.(2) Key land transfer patterns vary significantly between the ecological functional zones of the northern region of Egypt and the Nasser Reservoir. From 1985 to 2020, the Egypt’s northern region experienced significant shifts between arable land, sand, and impervious surfaces. The conversion of arable land to impervious surfaces represented 2.41% of the total arable land transfer area, while sand converted to impervious surfaces accounted for 11.68% of the total sand transfer area. In the Nasser Reservoir region, significant conversions occurred between water, grasslands, and sand. Sand converted to water made up 3.83% of the total sand transfer area, while grassland converted to water compriseed 5.38% of the total grassland transfer area. (3) The ecological benefits of the northern region of Egypt and the Nasser Reservoir have increased significantly. In northern region of Egypt, the primary drivers of this increase in ecological service value are the conversion of arable land and grasslands, along with the ecological development and utilization of sand. In the Nasser Reservoir area,the inflow of water and the continued outflow of sands are the main factors contributing to the rise in ecosystem service value. (4) Differentiated LUCC management should be implemented for different ecological functional zones. In northern region of Egypt, the focus should be on balancing ecological security with human development, while the Nasser Reservoir area should prioritize water resource protection and sustainable development. The research findings are not only significant for optimizing LUCC but also for enhancing ecosystem service functions in Egypt.

Variation in species-specific responses to habitat fragmentation and land cover structure in urban small mammal communities

Abstract Urbanization is a key driver of habitat loss and fragmentation worldwide, yet many urban ecosystems contain vegetated habitat patches that support diverse wildlife communities. Managing urban systems to support robust wildlife communities requires us to understand the mechanisms that drive the response of species to the urban environment. Small mammals are key components of terrestrial ecosystems (e.g., seed predators, prey) and likely also carry out these roles in urban ecosystems; however, the effects of urbanization on small mammal communities are understudied. To identify how species-specific responses to urban environments shape community composition, we quantified both overall community and species-specific changes in small mammal abundance across an urbanization gradient in a Midwestern US metropolitan area. We combined small mammal trapping and land cover data to generate a hierarchical community abundance model. Species diversity increased with increasing proportional cover of human-modified land cover (i.e., impervious surfaces and turfgrass). This finding is driven by high species diversity on sites bordering streams in mowed parks and low diversity on sites with high tree canopy closure. Additionally, modeling results indicated that species responded differently to landscape attributes, leading to variation in small mammal community composition across the urbanization gradient: prairie-associated species tended to be more abundant in tall vegetation bordering mowed parks while habitat generalists tended to be more abundant on sites with greater canopy closure and shrub cover. Our results suggest that studies that focus on community-level responses (e.g., species richness) to urbanization may miss important species-specific responses. It may be particularly important to assess both species-specific and community-level responses in cities at ecotones (e.g., between forest and grassland) where species with different habitat requirements may replace one another in different types of green spaces, thereby changing community composition without affecting species diversity or richness. Our findings also indicate that vegetated urban patches, especially patches with tall vegetation cover and low canopy cover, are important habitat for prairie-associated small mammal communities, providing conservation options in heavily altered landscapes.

Floods modeling and analysis for Dubai using HEC-HMS model and remote sensing using GIS

Floods accompanied by thunderstorms in developed cities are hazardous, causing damage to infrastructure. To secure infrastructure, it is important to employ an integrated approach, combining remote sensing, GIS and precipitation data. The model was developed based on the estimation of event-based runoff and investigated the relationship between runoff and impervious surfaces. The novel approach of combining Hydrologic Engineering Center’s River Analysis System (HEC-GeoRAS) along with satellite imagery was utilized, where spatial data was combined with real-time values to run the model. As a first step, the Hydrologic Engineering Center-Hydrologic Modeling System (HEC-HMS) model was fed with information about precipitation, slope, soil type, as well as land use and land cover. The results reveal that the subbasins of Deira, Nief and Jumeirah have the largest impervious area and, thus, a higher probability of flood occurrence. The model was calibrated and validated using previous runoff events and by comparing observed and simulated streak flow and peak discharge against those reported in previous studies. It was found that the model is efficient and can be used in similar regions.

Spatial Assessment of Urban Heat Island (UHI) in Kütahya using Landsat-8 Satellite Data

The Urban Heat Island (UHI) effect refers to the phenomenon where urban areas experience significantly higher temperatures than their rural surroundings due to human activities and modifications, such as replacing natural land cover with impervious surfaces, reducing vegetation, and increasing heat-absorbing materials. Kütahya central district has a dense population and building layout, which contributes to the intense UHI. Geographic Information System (GIS) and its tools are widely used in assessing UHI in urban areas, providing insights for both researchers and local authorities. Landsat-8 images acquired on August 8, 2023 (Path: 179, Row: 33, Cloud Cover: 0%) were utilized to create the Urban Heat Island (UHI) map for the study area. Through spatial analysis using Landsat-8 data for Kütahya city center, six different classes were defined, with the UHI map created using land surface temperature values. The highest and lowest UHI values vary between 4.245°C and -3.457°C. It has been observed that the average UHI increases by 12% in areas lacking dense building structures, characterized by rock surfaces and limited green areas. Conversely, in areas with parks, forests, and sparse settlements, the UHI decreases by 10%. With this study, a comprehensive evaluation of UHI was conducted for Kütahya city center. While the results obtained are expected to be an important resource for researchers and local authorities, they are also anticipated to be beneficial in the fields of engineering geology, urban geology, and urban planning.

Scale-Dependent Effects of Urban Canopy Cover, Canopy Volume, and Impervious Surfaces on Near-Surface Air Temperature in a Mid-Sized City

Cities are significantly warmer than their surrounding rural environments. Known as the ‘urban heat island effect’, it can affect the health of urban residents and lead to increased energy use, public health impacts, and damage to infrastructure. Although this effect is extensively researched, less is known about how landscape characteristics within cities affect local temperature variation. This study examined how tree canopy cover, canopy volume, and impervious surface cover affect daytime near-surface air temperature, and how these effects vary between different scales of analysis (10, 30, 60, 90 m radii), ranging from approximate street corridor to city block size. Temperature data were obtained from a car-mounted sensor, with traverse data points recorded during morning, afternoon, and evening times, plotted throughout the city of Portland, OR. The variability in near-surface air temperature was over 10° F during each traverse period. The results indicate that near-surface air temperature increased linearly with impervious surface cover and decreased linearly with tree canopy cover, with canopy volume reducing the temperature by 1° F for every 500 cubic feet of canopy volume for evening temperatures. The magnitude of the effect of tree canopy increased with spatial scale, with 60 and 90 m scales having the greatest measurable effect. Canopy volume had a positive relationship on presumed nighttime and early-morning temperatures at 60 and 90 m scales, potentially due to the impacts of wind fluctuation and air roughness. Canopy cover still contributed the largest overall decrease in street-scale temperatures. Increasing tree canopy cover and volume effectively explained the lower daytime and evening temperatures, while reducing impervious surface cover remains critical for reducing morning and presumed nighttime urban heat. The results may inform strategies for urban foresters and planners in managing urban land cover and tree planting patterns to build increased resiliency towards moderating urban temperature under warming climate conditions.

Peri-Urban Floodscapes: Identifying and Analyzing Flood Risk Areas in North Bhubaneswar in Eastern India

Peri-urban catchment areas are increasingly susceptible to floods due to rapid land use transformations and unplanned urban expansion. This study comprehensively examines flood vulnerability in the rapidly developing peri-urban areas of North Bhubaneswar, focusing on significant changes in Land Use/Land Cover (LULC) and hydrological dynamics from 2004 to 2024, utilizing Geographic Information System (GIS) tools. The analysis reveals substantial shifts in land use patterns, with the urban footprint expanding by 71.8%, cropland decreasing by 21.7%, and forest areas by 13.6%. These changes have led to increased impervious surfaces, resulting in higher surface runoff and decreased groundwater recharge, thereby exacerbating flood risks in the region. The GRID-based vulnerability analysis classifies 90 villages within the catchment area based on their vulnerability levels, identifying 20 villages as high-risk areas requiring urgent attention, 44 villages as medium vulnerable, and 26 villages as low vulnerable. These classifications are based on factors such as proximity to drainage networks, slope, geomorphology, and LULC characteristics, with areas near drainage channels and low-lying regions being prone to flooding. The analysis integrates multiple factors to provide a comprehensive assessment of flood risk, highlighting the need for sustainable land use planning, conservation of vegetated areas, and the implementation of advanced flood prevention strategies in the peri-urban areas. Extending this research to other fringe regions could offer further valuable insights, guiding flood prevention and sustainable development strategies for areas undergoing significant land use transformations to effectively mitigate future flood risks.