Spatio-temporal land cover dynamics and emerging landscape patterns in western part of Lagos State, Nigeria

Abstract Lagos State, which is home to Lagos metropolis and the eighteenth largest urban agglomeration in 2018 in the world, has been characterized by rapid urbanization. An earlier study of the eastern segment of the state revealed dramatic urban growth in previously rural local councils where it replaced mostly ecological assets. For a statewide view of the landscape pattern changes, this study examined the western segment of the state to characterize the magnitude and trend of these changes. This was done with Landsat images for 1984, 2006 and 2015 along with ENVI 5.0 software and FRAGSTATS v.4.2 spatial pattern analysis program. Results show that cumulatively, the ecological assets, which comprised 75% of the area in 1984, have been whittled down to about 34% by 2015 having been lost through urban development. At the council level in 2015, the highest growth areas, in decreasing order of magnitude, were Alimosho, Badagry, Ojo and Amuwo Odofin local government areas. Both class and landscape-level metrics confirmed the dominance and fragmentation of the resultant landscape in 2015 by urban development. In 1984, vegetation dominated the landscape at 55% coverage and was the largest feature with the highest area-weighted contiguity or connectedness index. Thirty-one years later in 2015, built-up areas were the dominant patch with 54% coverage and the highest contiguity and area-weighted contiguity index, higher than vegetation. These findings have narrowed the information gap about the spatial and temporal changes in the ecological assets of the western segment of Lagos State as a result of rapid urban expansion.

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Past and Future Trajectories of Farmland Loss Due to Rapid Urbanization Using Landsat Imagery and the Markov-CA Model: A Case Study of Delhi, India

Remote Sensing ◽

10.3390/rs11020180 ◽

2019 ◽

Vol 11 (2) ◽

pp. 180 ◽

Cited By ~ 10

Author(s):

Junmei Tang ◽

Liping Di

Keyword(s):

Transition Probabilities ◽

Urban Expansion ◽

Sustainable Urban Development ◽

Landsat Images ◽

Rapid Urbanization ◽

The Past ◽

Farmland Loss ◽

Rate Of Increase ◽

Multi Temporal ◽

Ca Model

This study integrated multi-temporal Landsat images, the Markov-Cellular Automation (CA) model, and socioeconomic factors to analyze the historical and future farmland loss in the Delhi metropolitan area, one of the most rapidly urbanized areas in the world. Accordingly, the major objectives of this study were: (1) to classify the land use and land cover (LULC) map using multi-temporal Landsat images from 1994 to 2014; (2) to develop and calibrate the Markov-CA model based on the Markov transition probabilities of LULC classes, the CA diffusion factor, and other ancillary factors; and (3) to analyze and compare the past loss of farmland and predict the future loss of farmland in relation to rapid urban expansion from the year 1995 to 2030. The predicted results indicated the high accuracy of the Markov-CA model, with an overall accuracy of 0.75 and Kappa value of 0.59. The predicted results showed that urban expansion is likely to continue to the year of 2030, though the rate of increase will slow down from the year 2020. The area of farmland has decreased and will continue to decrease at a relatively stable rate. The Markov-CA model provided a better understanding of the past, current, and future trends of LULC change, with farmland loss being a typical change in this region. The predicted result will help planners to develop suitable government policies to guide sustainable urban development in Delhi, India.

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Recording Urban Land Dynamic and Its Effects during 2000–2019 at 15-m Resolution by Cloud Computing with Landsat Series

Remote Sensing ◽

10.3390/rs12152451 ◽

2020 ◽

Vol 12 (15) ◽

pp. 2451

Author(s):

Yulin Dong ◽

Zhibin Ren ◽

Yao Fu ◽

Zhenghong Miao ◽

Ran Yang ◽

...

Keyword(s):

Climate Change ◽

Land Use ◽

High Resolution ◽

Land Cover ◽

Urban Development ◽

Green Space ◽

Urban Expansion ◽

Sustainable Urban Development ◽

Landsat Images ◽

Land Types

Cities, the core of the global climate change and economic development, are high impact land cover land use change (LCLUC) hotspots. Comprehensive records of land cover land use dynamics in urban regions are essential for strategic climate change adaption and mitigation and sustainable urban development. This study aims to develop a Google Earth Engine (GEE) application for high-resolution (15-m) urban LCLUC mapping with a novel classification scheme using pan-sharpened Landsat images. With this approach, we quantified the annual LCLUC in Changchun, China, from 2000 to 2019, and detected the abrupt changes (turning points of LCLUC). Ancillary data on social-economic status were used to provide insights on potential drivers of LCLUC by examining their correlation with change rate. We also examined the impacts of LCLUC on environment, specifically air pollution. Using this approach, we can classify annual LCLUC in Changchun with high accuracy (all above 0.91). The change detection based on the high-resolution wall-to-wall maps show intensive urban expansion with the compromise of cropland from 2000 to 2019. We also found the growth of green space in urban regions as the result of green space development and management in recent years. The changing rate of different land types were the largest in the early years of the observation period. Turning points of land types were primarily observed in 2009 and 2010. Further analysis showed that economic and industry development and population migration collectively drove the urban expansion in Changchun. Increasing built-up areas could slow wind velocity and air exchange, and ultimately led to the accumulation of PM2.5. Our implement of pan-sharpened Landsat images facilitates the wall-to-wall mapping of temporal land dynamics at high spatial resolution. The primary use of GEE for mapping urban land makes it replicable and transferable by other users. This approach is a first crucial step towards understanding the drivers of change and supporting better decision-making for sustainable urban development and climate change mitigation.

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Urban Expansion in Ethiopia from 1987 to 2017: Characteristics, Spatial Patterns, and Driving Forces

Sustainability ◽

10.3390/su11102973 ◽

2019 ◽

Vol 11 (10) ◽

pp. 2973 ◽

Cited By ~ 15

Author(s):

Berhanu Keno Terfa ◽

Nengcheng Chen ◽

Dandan Liu ◽

Xiang Zhang ◽

Dev Niyogi

Keyword(s):

Urban Development ◽

Spatial Patterns ◽

Urban Growth ◽

Driving Forces ◽

Addis Ababa ◽

Urban Expansion ◽

Spatiotemporal Analysis ◽

Rapid Urbanization ◽

Master Plans ◽

Coalescence Theory

Rapid urban growth in major cities of a country poses challenges for sustainable development. Particularly in Africa, the process of rapid urbanization is little understood and research is mostly limited to single cities. Thus, this study provides a comprehensive comparative analysis of the growth and spatial patterns of urban development in the three major cities of Ethiopia (Addis Ababa, Adama, and Hawassa) from 1987 to 2017. Also, the applicability of diffusion and coalescence theory on the evolution of these cities has been tested. Remote sensing and GIS technologies were combined with spatial metrics and morphological analysis was employed to undertake this study. The result revealed that all the studied cities experienced accelerated growth in the urbanized areas, but the cities with a larger initial urbanized size were associated with lower expansion rates. Differences in extent and direction of expansion in each city were mostly related to physical features, urban master plans, and policies, with an increase in the irregularity and dispersion of urban growth, representing strong evidence of urban sprawl. The spatiotemporal analysis confirmed that the urbanization processes of Addis Ababa and Adama were consistent and Hawassa city diverged from expectations based on diffusion and coalescence theory. In general, large cities with strong economic growth in a country fail to effectively control the scattered nature of urban growth, thus requiring aggressive policy intervention. The approach used in this study permits a deeper exploration of urban development patterns and the identification of priority areas for effective urban planning and management.

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Scenario-Based Simulation of Tianjin City Using a Cellular Automata–Markov Model

Sustainability ◽

10.3390/su10082633 ◽

2018 ◽

Vol 10 (8) ◽

pp. 2633 ◽

Cited By ~ 6

Author(s):

Ruci Wang ◽

Hao Hou ◽

Yuji Murayama

Keyword(s):

Land Use ◽

Cellular Automata ◽

Markov Model ◽

Urban Expansion ◽

Crop Protection ◽

Landsat Images ◽

Rapid Urbanization ◽

Kappa Value ◽

Development Goals ◽

Tianjin City

Rapid urbanization is occurring throughout China, especially in megacities. Using a land use model to obtain future land use/cover conditions is an essential method to prevent chaotic urban sprawl and imbalanced development. This study utilized historical Landsat images to create land use/cover maps to predict the land use/cover changes of Tianjin city in 2025 and 2035. The cellular automata–Markov (CA–Markov) model was applied in the simulation under three scenarios: the environmental protection scenario (EPS), crop protection scenario (CPS), and spontaneous scenario (SS). The model achieved a kappa value of 86.6% with a figure of merit (FoM) of 12.18% when compared to the empirical land use/cover map in 2015. The results showed that the occupation of built-up areas increased from 29.13% in 2015 to 38.68% (EPS), 36.18% (CPS), and 47.94% (SS) in 2035. In this context, current urbanization would bring unprecedented stress on agricultural resources and forest ecosystems, which could be attenuated by implementing protection policies along with decelerating urban expansion. The findings provide valuable information for urban planners to achieve sustainable development goals.

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Spatial-Temporal Dynamic Analysis of Land Use and Landscape Pattern in Guangzhou, China: Exploring the Driving Forces from an Urban Sustainability Perspective

Sustainability ◽

10.3390/su11236675 ◽

2019 ◽

Vol 11 (23) ◽

pp. 6675 ◽

Cited By ~ 1

Author(s):

Siqi Liu ◽

Qing Yu ◽

Chen Wei

Keyword(s):

Land Use ◽

Land Use Change ◽

Urban Development ◽

Landscape Pattern ◽

Urban Land ◽

Landscape Patterns ◽

Dominant Factor ◽

Rapid Urbanization ◽

Agricultural Conversion ◽

Pattern Change

Rapid urbanization is one of the most important factors causing land-use change, which mainly results from the orientation of government policies, adjustment of industrial structure, and migration of the rural population. Land use and land cover change (LUCC) is the natural foundation of urban development that is significantly influenced by human activities. By analyzing the LUCC and its inner driving force, as well as landscape pattern change, human activity and urban sustainable development can be better understood. This research adopted a geographic information system (GIS) and remote sensing (RS) technology to comprehensively analyze land use of Guangzhou, respectively, in 1995, 2005, and 2015. Fragmentation Statistics (FRAGSTATS) is the most authoritative software to calculate landscape metrics. Landscape pattern change was analyzed by FRAGSTATS. The results showed that urban land significantly increased from 16.33% in 1995 to 36.05% in 2015. Farmland greatly decreased from 45.16% in 1995 to 27.82% in 2005 and then slightly decreased to 25.10% in 2015. In the first decade, the non-agricultural conversion of rural land and the expansion of urban land was the dominant factor that led to the change. In the second decade, urban land had been supplemented through the redevelopment of low-efficiency land. The fragmentation of landscape patterns significantly increased from 1995 to 2005 and slightly decreased from 2005 to 2015. It indicated that the change in land use in the second decade was different from that in the first. This difference mainly resulted from three aspects: (1) urban development area and ecological conservation area were clearly defined in Guangzhou; (2) many small towns had developed into urban centers, and the scattered urban land gathered into these centers; (3) the establishment of greenway improved the connection of fragmented patches. After that, this study discussed land-use change and its causes and proposed the trend of urban development from the perspective of sustainability.

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Evaluation of the Fairness of Urban Lakes’ Distribution Based on Spatialization of Population Data: A Case Study of Wuhan Urban Development Zone

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph16244994 ◽

2019 ◽

Vol 16 (24) ◽

pp. 4994 ◽

Cited By ~ 1

Author(s):

Jing Wu ◽

Shen Yang ◽

Xu Zhang

Keyword(s):

Urban Development ◽

Spatial Data ◽

Central City ◽

Urban Expansion ◽

Population Data ◽

City Center ◽

Rapid Urbanization ◽

Development Zone ◽

Urban Lakes ◽

The City

Lake reclamation for urban construction has caused serious damage to lakes in cities undergoing rapid urbanization. This process affects urban ecological environment and leads to inconsistent urban expansion, population surge, and uneven distribution of urban lakes. This study measured the fairness of urban lakes’ distribution and explored the spatial matching relationship between service supply and user group demand. The interpretation and analysis of Wuhan’s remote sensing images, population, administrative area, traffic network, and other data in 2018 were used as the basis. Specifically, the spatial distribution pattern and fairness of lakes’ distribution in Wuhan urban development zone were investigated. This study establishes a geographic weighted regression (GWR) model of land cover types and population data based on a spatialization method of population data based on land use, and uses population spatial data and network accessibility analysis results to evaluate lake service levels in the study area. Macroscopically, the correlation analysis of sequence variables and Gini coefficient analysis method are used to measure the fairness of the Wuhan lake distribution problem and equilibrium degree, and the location entropy analysis is used to quantitatively analyze the fairness of lakes and Wuhan streets from the perspective of supply and demand location entropy. Levels improve the accuracy of the research. Results showed that (1) the area covered by lakes in Wuhan urban development zone is 1007.96 km2 within 60-min of walking, accounting for 30.6% of the total area of the study area. This area can house 5,050,275 people, accounting for 60.8% of Wuhan’s total population. (2) The lakes in the central city area are less fair than the lakes outside the Third Ring Road. (3) The service level of North Lake is the highest among all the lakes in the study area, and that of Hou Lake is the lowest. (4) The spatial layout of the fairness of the lakes’ distribution is roughly distributed in circles. The fairness level collapses toward the city center, indicating that the closer to the city center, the lower the fairness level.

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Accessibilty of public urban green spaces within the spatial metropolitan network of Doha, Qatar

Proceedings of the 56th ISOCARP World Planning Congress ◽

10.47472/kuxq1422 ◽

2020 ◽

Author(s):

Heba T. Tannous ◽

◽

Mark David Major ◽

Raffaello Furlan ◽

◽

...

Keyword(s):

Urban Planning ◽

Urban Expansion ◽

Well Being ◽

The State ◽

Capital City ◽

Green Spaces ◽

Rapid Urbanization ◽

Urban Green ◽

Urban Green Spaces ◽

The World

Most people regard green spaces as a necessity to enhance the physical health and psychological well-being of residents in promoting the general health and welfare of citizens and the environment (Röbbel, 2016). In the Modern Era, the availability of green spaces has become an integral component of urban planning for sustaining the quality of life in city environments, especially since the dawn of the 20th century. Due to globalization in rapidly-developing cities around the world, studies about green spaces are becoming an increasingly important part of the urban planning process (Mitchell and Popham, 2007). Accessibility can play an essential role in determining the location of green public facilities to maximize their usability for large populations, or otherwise limit use to a smaller community (Ottensmann and Greg, 2008). However, some public green spaces are inefficiently located or distributed in urban environments (Beatley, 2000, Gehl, 2010, Gehl and Svarre, 2013). In this paper, the accessibility of urban green spaces means the ease of reaching such locations from many origins within the urban spatial network from the macro- to the micro-scale. The inaccessibility or absence of green spaces in some urban areas is a notable consequence of rapid urbanization in many cities around the world. It is especially noticeable in the capital city of Doha in the State of Qatar, where rapid urban expansion and globalization has had a significant impact on the quality and quantity of green spaces available (Salama and Wiedmann, 2013a). The paper utilizes the network analysis techniques of space syntax to objectively investigate the accessibility of urban green parks and promenades in the metropolitan region of Doha (Penn et al., 1998, Hillier et al., 1993, Hillier and Hanson, 1984). At the heart of the paper is the question, does the size and location of urban green spaces follow a discernible spatial logic in terms of accessibility, linked to the design intent of public planning policies? Some findings in the paper indicate there is distinctive spatial and social logic to the physical and spatial characteristics of urban green spaces above a certain size in terms of metric area. In contrast, these characteristics in smaller urban green spaces tend to be more random, primarily due to issues of land availability and amenity provision in private developments. We conclude by discussing the potential implications of the study for public planning policy about green urbanism in the State of Qatar and other rapidly urbanizing cities around the world

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Variations in the Effects of Landscape Patterns on the Urban Thermal Environment during Rapid Urbanization (1990–2020) in Megacities

Remote Sensing ◽

10.3390/rs13173415 ◽

2021 ◽

Vol 13 (17) ◽

pp. 3415

Author(s):

Haipeng Ye ◽

Zehong Li ◽

Ninghui Zhang ◽

Xuejing Leng ◽

Dan Meng ◽

...

Keyword(s):

Green Space ◽

Thermal Environment ◽

Urban Expansion ◽

Urban Green Space ◽

Landscape Patterns ◽

Cooling Effect ◽

Landscape Configuration ◽

Rapid Urbanization ◽

Urban Green ◽

Urban Thermal Environment

Deterioration of the urban thermal environment, especially in megacities with intensive populations and high densities of impervious surfaces, is a global issue resulting from rapid urbanization. The effects of landscape patterns on the urban thermal environment within a single area or single period have been well documented. Few studies, however, have explored whether the effects can be adapted to various cities at different urbanization stages. This paper investigated the variations of these effects in the five largest and highly urbanized megacities of China from 1990 to 2020 using various geospatial approaches, including concentric buffer analysis, correlation analysis, and hierarchical ridge regression models. The results indicated that the effects of landscape patterns on the urban thermal environment were greatly variable at different urbanization stages. Although landscape composition was more important than landscape configuration in determining the urban thermal environment, the standard coefficients of composition metrics continuously decreased from 1990 to 2020. However, configuration metrics, such as patch density, edge density, and shape complexity, could affect the land surface temperature (LST) to a larger extent at the highly urbanized stage. The urbanization process could also affect the cooling effect of urban green space. At the initial stage of rapid urban expansion in approximately 2000, urban green space explained the most variation in LST, with a value as high as 10%. To maximize the cooling effect, the spatial arrangement of urban green space should be highlighted in the region that was 10–15 km from the city center, where the mean LST experienced a significant decline. These results may provide deeper insights into improving the urban thermal environment by targeted strategies in optimizing landscape patterns for areas at different urbanization stages.

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Sources of and Control Measures for PTE Pollution in Soil at the Urban Fringe in Weinan, China

Land ◽

10.3390/land10070762 ◽

2021 ◽

Vol 10 (7) ◽

pp. 762

Author(s):

Lei Han ◽

Rui Chen ◽

Zhao Liu ◽

Shanshan Chang ◽

Yonghua Zhao ◽

...

Keyword(s):

Land Use ◽

Urban Expansion ◽

Pollution Sources ◽

Urban Fringe ◽

Control Measures ◽

Atomic Fluorescence Spectrometry ◽

Human Beings ◽

Rapid Urbanization ◽

Kriging Interpolation Method ◽

The Impact

The environment of the urban fringe is complex and frangible. With the acceleration of industrialization and urbanization, the urban fringe has become the primary space for urban expansion, and the intense human activities create a high risk of potentially toxic element (PTE) pollution in the soil. In this study, 138 surface soil samples were collected from a region undergoing rapid urbanization and construction—Weinan, China. Concentrations of As, Pb, Cr, Cu, and Ni (Inductively Coupled Plasma Mass Spectrometry, ICP-MS) and Hg (Atomic Fluorescence Spectrometry, AFS) were measured. The Kriging interpolation method was used to create a visualization of the spatial distribution characteristics and to analyze the pollution sources of PTEs in the soil. The pollution status of PTEs in the soil was evaluated using the national environmental quality standards for soils in different types of land use. The results show that the content range of As fluctuated a small amount and the coefficient of variation is small and mainly comes from natural soil formation. The content of Cr, Cu, and Ni around the automobile repair factory, the prefabrication factory, and the building material factory increased due to the deposition of wear particles in the soil. A total of 13.99% of the land in the study area had Hg pollution, which was mainly distributed on category 1 development land and farmland. Chemical plants were the main pollution sources. The study area should strictly control the industrial pollution emissions, regulate the agricultural production, adjust the land use planning, and reduce the impact of pollution on human beings. Furthermore, we make targeted remediation suggestions for each specific land use type. These results are of theoretical significance, will be of practical value for the control of PTEs in soil, and will provide ecological environmental protection in the urban fringe throughout the urbanization process.

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Land Use and Land Cover Change Assessment in the Context of Flood Hazard in Lagos State, Nigeria

Water ◽

10.3390/w13081105 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1105

Author(s):

Dorcas Idowu ◽

Wendy Zhou

Keyword(s):

Land Use ◽

Land Cover ◽

Flood Hazard ◽

The State ◽

Land Cover Type ◽

Lulc Change ◽

Cover Type ◽

Lulc Changes ◽

Lagos State ◽

Very High

Incessant flooding is a major hazard in Lagos State, Nigeria, occurring concurrently with increased urbanization and urban expansion rate. Consequently, there is a need for an assessment of Land Use and Land Cover (LULC) changes over time in the context of flood hazard mapping to evaluate the possible causes of flood increment in the State. Four major land cover types (water, wetland, vegetation, and developed) were mapped and analyzed over 35 years in the study area. We introduced a map-matrix-based, post-classification LULC change detection method to estimate multi-year land cover changes between 1986 and 2000, 2000 and 2016, 2016 and 2020, and 1986 and 2020. Seven criteria were identified as potential causative factors responsible for the increasing flood hazards in the study area. Their weights were estimated using a combined (hybrid) Analytical Hierarchy Process (AHP) and Shannon Entropy weighting method. The resulting flood hazard categories were very high, high, moderate, low, and very low hazard levels. Analysis of the LULC change in the context of flood hazard suggests that most changes in LULC result in the conversion of wetland areas into developed areas and unplanned development in very high to moderate flood hazard zones. There was a 69% decrease in wetland and 94% increase in the developed area during the 35 years. While wetland was a primary land cover type in 1986, it became the least land cover type in 2020. These LULC changes could be responsible for the rise in flooding in the State.

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