Spatial Analysis of Urbanization Patterns in Four Rapidly Growing South Asian Cities Using Sentinel-2 Data

The rapid and dominant urbanization in Asian cities has fueled concerns regarding the local and global efforts toward urban sustainability. Specifically, South Asian cities have been a topical issue concerning ecological and environmental threats due to their unplanned and haphazard urban development. However, comparative urbanization studies in South Asian cities remain uncommon. Therefore, in this study, we sought to comparatively examine the land use and land cover (LULC) dynamics and to detect the urbanization patterns of four rapidly developing South Asian lowland cities: Mumbai (India), Colombo (Sri Lanka), Karachi (Pakistan), and Dhaka (Bangladesh). Sentinel-2 (10 m) data and various geospatial approaches, including urban–rural gradient and grid-based methods, statistics, and urban landscape metric techniques, were used to facilitate the analysis. The study revealed that Mumbai, Karachi, and Dhaka had larger built-up landscapes compared to Colombo. Mumbai had the highest percentage of green spaces, followed by Colombo. Dhaka and Karachi had relatively small percentages of green spaces. Colombo and Dhaka had more croplands, which consistently increased along the urban–rural gradient compared to Mumbai and Karachi. Karachi showed that the only major land use was built-up, while most of the areas were left as open lands. On the other hand, Colombo’s urban setup was more fragmented than the other three cities. Mumbai and Karachi had larger patches of urban footprints compared to Colombo and Dhaka. Thus, this study provides vital information on the past land utilization priorities in the four cities, and comparatively proffers guidance on certain critical areas of focus for local, regional, and global future sustainable urban planning.

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Spatial Analysis of Surface Urban Heat Islands in Four Rapidly Growing African Cities

Remote Sensing ◽

10.3390/rs11141645 ◽

2019 ◽

Vol 11 (14) ◽

pp. 1645 ◽

Cited By ~ 26

Author(s):

Matamyo Simwanda ◽

Manjula Ranagalage ◽

Ronald C. Estoque ◽

Yuji Murayama

Keyword(s):

Urban Heat Island ◽

Green Space ◽

Urban Landscape ◽

Impervious Surface ◽

Green Spaces ◽

Heat Island ◽

Impervious Surfaces ◽

African Cities ◽

Urban Rural ◽

Urban Heat

Africa’s unprecedented, uncontrolled and unplanned urbanization has put many African cities under constant ecological and environmental threat. One of the critical ecological impacts of urbanization likely to adversely affect Africa’s urban dwellers is the urban heat island (UHI) effect. However, UHI studies in African cities remain uncommon. Therefore, this study attempts to examine the relationship between land surface temperature (LST) and the spatial patterns, composition and configuration of impervious surfaces/green spaces in four African cities, Lagos (Nigeria), Nairobi (Kenya), Addis Ababa (Ethiopia) and Lusaka (Zambia). Landsat OLI/TIRS data and various geospatial approaches, including urban–rural gradient, urban heat island intensity, statistics and urban landscape metrics-based techniques, were used to facilitate the analysis. The results show significantly strong correlation between mean LST and the density of impervious surface (positive) and green space (negative) along the urban–rural gradients of the four African cities. The study also found high urban heat island intensities in the urban zones close (0 to 10 km) to the city center for all cities. Generally, cities with a higher percentage of the impervious surface were warmer by 3–4 °C and vice visa. This highlights the crucial mitigating effect of green spaces. We also found significant correlations between the mean LST and urban landscape metrics (patch density, size, shape, complexity and aggregation) of impervious surfaces (positive) and green spaces (negative). The study revealed that, although most African cities have relatively larger green space to impervious surface ratio with most green spaces located beyond the urban footprint, the UHI effect is still evident. We recommend that urban planners and policy makers should consider mitigating the UHI effect by restoring the urban ecosystems in the remaining open spaces in the urban area and further incorporate strategic combinations of impervious surfaces and green spaces in future urban and landscape planning.

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INTERROGATING CONCEPTIONS OF ‘MODERNITY’ AND ‘TRADITION’ IN THE PRODUCTION OF THE BUILT ENVIRONMENT IN SOUTH ASIA•

Journal of Research in Architecture and Planning ◽

10.53700/jrap1812015_1 ◽

2015 ◽

Vol 18 (1) ◽

pp. 1-10

Author(s):

Sarwat Viqar

Keyword(s):

Built Environment ◽

South Asia ◽

South Asian ◽

Urban Landscape ◽

18Th Century ◽

The Other ◽

New Order ◽

British Colonialism ◽

Prescriptive Model ◽

Colonial Order

It has been argued that concepts of modernity and tradition are historical categories that emerged in the context of imperial encounters with the .other. during Colonization. This paper will show how the contingent nature of these categories becomes apparent when considering the production of the built environment in South Asia. The advent of British Colonialism in the 18th century precipitated a significant change in the urban landscape of South Asian cities. It also created a binary conception of a modern order that was a break from the local or native order of space. From then on, modernity became the institution of a liberal western order and tradition was what was retained by the natives that had been eclipsed by the new order. This trope of the dysfunctional Pre-Modern entered into native, nationalist imaginings of the past as well by establishing a binary between what was and what came after as being forever opposed to each other. In order to assert one, the other had to be negated. The Imperialist narrative achieved this through asserting the inherently moral nature and legitimacy of the Colonial order while the Nationalist narrative strove to recover the .tradition. that had been displaced by the Colonial order. The modern disciplines introduced with Colonial rule did provide a powerful prescriptive model of urban planning that created a privileged position for what has come to be seen as the modern form of the city. However, drawing upon contemporary South Asian urban historiography and research it is argued here that this order was constantly destabilized by native resistance, appropriation, hybridity and accommodation. In doing so, it appears that the production and reproduction of space in the built environment of South Asia constantly challenges notions of a dynamic, all-consuming modernity against a static tradition that needs to be preserved. Keywords: Modernity, tradition, colonial, culture

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Characteristics of Post Socialist Spatial Development of the Functional Urban Area of Veszprém, Hungary

Journal of Environmental Geography ◽

10.2478/jengeo-2019-0010 ◽

2019 ◽

Vol 12 (3-4) ◽

pp. 33-43 ◽

Cited By ~ 1

Author(s):

Vera Iváncsics ◽

Krisztina Filepné Kovács

Keyword(s):

Land Use ◽

Urban Area ◽

Urban Sprawl ◽

Urban Areas ◽

Urban Landscape ◽

Land Use Changes ◽

Sustainable Land Use ◽

Nature Protection ◽

Important Trend ◽

Urban Rural

Abstract The post-socialist era resulted remarkable changes in urban landscape in Eastern Europe and in Hungary. The special circumstances caused moderate level of urbanisation and special patterns of urban sprawl, traceable in land use changes. The urban sprawl and suburbanisation became an important trend around smaller Hungarian cities as well. Regulators are eager to rule the evolution of spaces, however, it is hard to control all aspects of land use. The research presented in this paper shows the dynamics of new artificial areas with the help of land use changes from the Corine Database for the functional urban area around Veszprém and attempts to find the most important policy responses to the growing artificial surfaces after transition. The research questions are: What are the most important trends in changing in-built areas in a small city after the transition? What kind of new artificial areas appeared and where are they situated? Were the land use plans and nature protection effective tools for manage urban sprawl? With the help of Corine land use changes between 1990-2018 the most important spatial changes are shown, and the different peri-urban areas are compared around the core town. Attention is drawn to the importance of regulation for sustainable land use and protection of resources. It also highlights the importance of the regulatory power of municipalities. Changes in the environment of Veszprém may give inspiration for the rethinking the relationship of urban-rural, and catchment area and core town.

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Landfills as anthropogenic landforms in urban environment from Neamţ county

10.31235/osf.io/a54td ◽

2016 ◽

Author(s):

Florin Constantin MIHAI

Keyword(s):

Land Use ◽

Urban Environment ◽

Urban Landscape ◽

Critical Infrastructure ◽

Local Environment ◽

The Other ◽

Mountainous Regions ◽

A Site ◽

Complex Pollution

Landfills are the most common and easiest methods to dispose the municipalwaste in Romania and still prevails in current waste management options.This type of critical infrastructure was designed to dispose urban wastegenerated over years or even decades and ultimately led to creating newlandforms in the urban landscape. On the other hand, these sites are majorsources of complex pollution unfulfilling EU regulations, being scheduledto be closed. This paper aims to analyze landfills as anthropogeniclandforms by applying GIS techniques emphasizing them in a geographicalcontext and not only in situ. The location of these sites usually onalluvial plains of rivers leading to positive landforms that may changehydrogeomorphology dynamics or to be exposed to the floods. The other side,their location in hilly or mountainous regions increase vulnerability toother geomorphological process (gully erosion, landslide). Also, theextension of human settlements and land use is influenced by the presenceof such a site either it is closed. The implications of these landforms arevaried and must belinked to geographical realities from around. Thus, the mapping of theseanthropogenic landforms contribute to a better understanding of thesystemic interactions from the local environment. This approach may be animportant tool for EIA studies, in the process of rehabilitation,post-monitoring andreintegration of these landfills.

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Interrelationships between municipal spatial policy strategy and airport operation and development. Lodz Airport case study

Urban Development Issues ◽

10.2478/udi-2018-0029 ◽

2018 ◽

Vol 59 (1) ◽

pp. 65-79

Author(s):

Katarzyna Nikorowicz-Zatorska

Keyword(s):

Land Use ◽

Urban Planning ◽

Cultural Development ◽

The Other ◽

Local Authorities ◽

Spatial Management ◽

The One ◽

Surrounding Areas

Abstract The present paper focuses on spatial management regulations in order to carry out investment in the field of airport facilities. The construction, upgrades, and maintenance of airports falls within the area of responsibility of local authorities. This task poses a great challenge in terms of organisation and finances. On the one hand, an active airport is a municipal landmark and drives local economic, social and cultural development, and on the other, the scale of investment often exceeds the capabilities of local authorities. The immediate environment of the airport determines its final use and prosperity. The objective of the paper is to review legislation that affects airports and the surrounding communities. The process of urban planning in Lodz and surrounding areas will be presented as a background to the problem of land use management in the vicinity of the airport. This paper seeks to address the following questions: if and how airports have affected urban planning in Lodz, does the land use around the airport prevent the development of Lodz Airport, and how has the situation changed over the time? It can be assumed that as a result of lack of experience, land resources and size of investments on one hand and legislative dissonance and peculiar practices on the other, aviation infrastructure in Lodz is designed to meet temporary needs and is characterised by achieving short-term goals. Cyclical problems are solved in an intermittent manner and involve all the municipal resources, so there’s little left to secure long-term investments.

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Human density, economic level and frequency of canine helminths in Buenos Aires

Journal of Helminthology ◽

10.1017/s0022149x21000055 ◽

2021 ◽

Vol 95 ◽

Author(s):

D. Rubel ◽

N. Flaibani

Keyword(s):

Linear Models ◽

Buenos Aires ◽

Toxocara Canis ◽

The Other ◽

Green Spaces ◽

Cross Sectional ◽

Independent Variables ◽

Economic Level ◽

Faecal Samples ◽

Human Density

Abstract The aim of this study was to explore through cross-sectional study the variation in the prevalence of parasitic helminths in canine faeces collected from green spaces of Buenos Aires according to the human density (HD) and economic level (EL) in the surroundings. HD and EL were considered as independent variables with three categories each. Twenty public squares (one hectare of surface) were randomly selected for each existing combination of the two independent variables. Ten random samples of fresh canine faeces were obtained in each square and analysed for helminths by the sedimentation and flotation techniques. The prevalence for each of the species was analysed using generalized linear models (GLM). The prevalence was modelled with a binomial error distribution and a logit link function. Helminth eggs were detected in 45 out of the 200 (22.5%) faecal samples collected and in 18 of the 20 green spaces sampled. The species observed were Ancylostoma caninum (13% of samples), Trichuris vulpis (8%) and Toxocara canis (4.5%). The GLM indicated that the prevalence of A. caninum in the slum areas (very high HD and very low EL) was higher than that in the other areas studied. However, the HD seemed to contribute more than the EL to the variations in the prevalence of A. caninum in faecal samples. The GLM showed no differences in the prevalence of the other parasite species for the different levels of the independent variables.

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Mapping Public Urban Green Spaces Based on OpenStreetMap and Sentinel-2 Imagery Using Belief Functions

ISPRS International Journal of Geo-Information ◽

10.3390/ijgi10040251 ◽

2021 ◽

Vol 10 (4) ◽

pp. 251

Author(s):

Christina Ludwig ◽

Robert Hecht ◽

Sven Lautenbach ◽

Martin Schorcht ◽

Alexander Zipf

Keyword(s):

Vegetation Index ◽

Normalized Difference Vegetation Index ◽

Open Data ◽

Green Spaces ◽

Data Sets ◽

Urban Green ◽

Urban Green Spaces ◽

Urban Quality Of Life ◽

Shafer Theory ◽

Sentinel 2

Public urban green spaces are important for the urban quality of life. Still, comprehensive open data sets on urban green spaces are not available for most cities. As open and globally available data sets, the potential of Sentinel-2 satellite imagery and OpenStreetMap (OSM) data for urban green space mapping is high but limited due to their respective uncertainties. Sentinel-2 imagery cannot distinguish public from private green spaces and its spatial resolution of 10 m fails to capture fine-grained urban structures, while in OSM green spaces are not mapped consistently and with the same level of completeness everywhere. To address these limitations, we propose to fuse these data sets under explicit consideration of their uncertainties. The Sentinel-2 derived Normalized Difference Vegetation Index was fused with OSM data using the Dempster–Shafer theory to enhance the detection of small vegetated areas. The distinction between public and private green spaces was achieved using a Bayesian hierarchical model and OSM data. The analysis was performed based on land use parcels derived from OSM data and tested for the city of Dresden, Germany. The overall accuracy of the final map of public urban green spaces was 95% and was mainly influenced by the uncertainty of the public accessibility model.

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Evaluating the Potentiality of Sentinel-2 for Change Detection Analysis Associated to LULUCF in Wallonia, Belgium

Land ◽

10.3390/land10010055 ◽

2021 ◽

Vol 10 (1) ◽

pp. 55

Author(s):

Odile Close ◽

Sophie Petit ◽

Benjamin Beaumont ◽

Eric Hallot

Keyword(s):

Climate Change ◽

Land Use ◽

Change Detection ◽

Signal To Noise Ratio ◽

Land Conversion ◽

Sustainable Resources ◽

Detection Techniques ◽

Detection Analysis ◽

Conversion Rates ◽

Sentinel 2

Land Use/Cover changes are crucial for the use of sustainable resources and the delivery of ecosystem services. They play an important contribution in the climate change mitigation due to their ability to emit and remove greenhouse gas from the atmosphere. These emissions/removals are subject to an inventory which must be reported annually under the United Nations Framework Convention on Climate Change. This study investigates the use of Sentinel-2 data for analysing lands conversion associated to Land Use, Land Use Change and Forestry sector in the Wallonia region (southern Belgium). This region is characterized by one of the lowest conversion rates across European countries, which constitutes a particular challenge in identifying land changes. The proposed research tests the most commonly used change detection techniques on a bi-temporal and multi-temporal set of mosaics of Sentinel-2 data from the years 2016 and 2018. Our results reveal that land conversion is a very rare phenomenon in Wallonia. All the change detection techniques tested have been found to substantially overestimate the changes. In spite of this moderate results our study has demonstrated the potential of Sentinel-2 regarding land conversion. However, in this specific context of very low magnitude of land conversion in Wallonia, change detection techniques appear to be not sufficient to exceed the signal to noise ratio.

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