Multi-Scenario Simulation for the Consequence of Urban Expansion on Carbon Storage: A Comparative Study in Central Asian Republics

There is growing concern about the consequences of future urban expansion on carbon storage as our planet experiences rapid urbanization. While an increasing body of literature was focused on quantifying the carbon storage impact of future urban expansion across the globe, rare attempts were made from the comparative perspective on the same scale, particularly in Central Asia. In this study, Central Asian capitals, namely Ashkhabad, Bishkek, Dushanbe, Nur Sultan, and Tashkent, were used as cases. According to the potential impacts of BRI (Belt and Road Initiative) on urban expansion, baseline development scenario (BDS), cropland protection scenario (CPS), and ecological protection scenario (EPS) were defined. We then simulated the carbon storage impacts of urban expansion from 2019 to 2029 by using Google Earth Engine, the Future Land Use Simulation model, and the Integrated Valuation of Environmental Services and Tradeoffs model. We further explored the drivers for carbon storage impacts of future urban expansion in five capitals. The results reveal that Nur Sultan will experience carbon storage growth from 2019 to 2029 under all scenarios, while Ashkhabad, Bishkek, Dushanbe, and Tashkent will show a decreasing tendency. EPS and CPS will preserve the most carbon storage for Nur Sultan and the other four cities, respectively. The negative impact of future urban expansion on carbon storage will be evident in Ashkhabad, Bishkek, Dushanbe, and Tashkent, which will be relatively inapparent in Nur Sultan. The potential drivers for carbon storage consequences of future urban expansion include agricultural development in Bishkek, Dushanbe, and Tashkent, desert city development in Ashkhabad, and prioritized development of the central city and green development in Nur Sultan. We suggest that future urban development strategies for five capitals should be on the basis of differentiated characteristics and drivers for the carbon storage impacts of future urban expansion.

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Land Subsidence Induced by Rapid Urbanization in Arid Environments: A Remote Sensing-Based Investigation

Remote Sensing ◽

10.3390/rs13061109 ◽

2021 ◽

Vol 13 (6) ◽

pp. 1109

Author(s):

Abdulaziz Aljammaz ◽

Mohamed Sultan ◽

Moein Izadi ◽

Abotalib Z. Abotalib ◽

Mohamed S. Elhebiry ◽

...

Keyword(s):

Land Subsidence ◽

Urban Expansion ◽

Integrated Approach ◽

Test Site ◽

Google Earth ◽

Septic Systems ◽

Arid Environments ◽

Rapid Urbanization ◽

Groundwater Levels ◽

Wastewater Effluents

The rapid increase in the population of many of the older major cities within the countries of the Saharan-Arabian Desert is steering vast and disorganized urban expansion and in many cases introducing adverse environmental impacts such as soil erosion, rise in groundwater levels, and contamination of shallow aquifers, as well as development of deformational features including land subsidence. Using the rapidly growing city of Riyadh (1992: 467 km2; 2018: 980 km2), the capital of the Kingdom of Saudi Arabia as a test site, we utilized Small Baseline Subset (SBAS) interferometric analyses of 2016 to 2018 Sentinel-1 images together with multi-temporal high-resolution images viewable on Google Earth, GPS, field, land use land cover (LULC), and geological data to assess the distribution and rates of land subsidence and their causal effects. Three main causes of subsidence were identified and assessed: (1) discharge of wastewater effluents from septic systems in newly urbanized areas that lead to an increase in soil moisture, rise in groundwater levels, waterlogging, and wetting and hydrocompaction of dry alluvium loose sediments causing land subsidence (up to −20 mm/y) in wadis and lowlands; (2) the subsurface dissolution of karst formation by wastewater effluents and the collapse of voids and cavities at depth under stresses introduced by heavy construction machinery, causing sagging and land subsidence (up to −5 mm/y); and (3) leveling, compaction, and degradation of municipal and building waste materials in organized landfills and disorganized dump sites that resulted in significant land subsidence (up to −21 mm/y) and differential settling that could jeopardize the stability of structures erected over these sites. Our findings highlight the potential use of the advocated integrated approach to assess the nature and extent of land deformation associated with rapid urban growth in arid lands, and to identify areas most impacted for the purpose of directing and prioritizing remediation efforts.

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Projection of future direct and indirect impacts of urban expansion on carbon storage: A case study in Hubei, China

10.5194/egusphere-egu2020-21945 ◽

2020 ◽

Author(s):

Lanping Tang ◽

Xinli Ke

Keyword(s):

Carbon Storage ◽

Global Climate ◽

Urban Expansion ◽

Natural Habitat ◽

Rapid Urbanization ◽

Conservation Policies ◽

Ecological Protection ◽

Direct And Indirect Impacts ◽

Indirect Impacts

Urban expansion encroaches on natural habitat, which seriously affects carbon storage which plays an important role in global climate change. The projection of future effects of urban expansion on carbon storage have been the subject of attention, previous studies explored its direct impacts but ignored indirect effects: cropland loss caused by urban expansion needs to compensation from natural habitat for food security, which also affects carbon storage. China, as a populated country, is at an important stage of cropland conservation policies reform, rapid urbanization, and constructing of eco-civilization. In this case, it&#8217;s vital to figure out the change of carbon storage due to the direct and indirect impacts of urban expansion in the future. Taking Hubei as the study area, the aim of this study is to project both direct impacts (DI) and indirect impacts (II) of urban expansion on carbon storage during 2010&#8211;2030. Three scenarios are developed by integrating the current situation and policies: the scenarios where urban continues to expand and the cropland conservation policies are implemented with the priority to cropland in quantity (S1), with the priority to cropland in quantity and quality (S2), with the priority to cropland in quantity and quality, and ecological protection is also concerned (S3). Results show that, the total loss of carbon storage caused by urban expansion will be 1.83Tg&#8226;C (DI: 0.95Tg&#8226;C; II:0.88Tg&#8226;C) under the S1 scenario, will be 2.15Tg&#8226;C (DI: 1.46Tg&#8226;C; II:0.69Tg&#8226;C) under the S2 scenario, and will be 1.49Tg&#8226;C (DI: 0.94Tg&#8226;C; II: 0.55Tg&#8226;C) under the S3 scenario. This indicates that ignoring the indirect impacts of urban expansion on carbon storage will lead to the underestimation of real impacts of urban expansion with 48%, 32%, and 63%, respectively. This study highlights the importance of taking the carbon storage loss caused by the indirect impacts of urban expansion into consideration.

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Impacts of Strict Cropland Protection on Water Yield: A Case Study of Wuhan, China

Sustainability ◽

10.3390/su11010184 ◽

2019 ◽

Vol 11 (1) ◽

pp. 184 ◽

Cited By ~ 1

Author(s):

Xinli Ke ◽

Liye Wang ◽

Yanchun Ma ◽

Kunpeng Pu ◽

Ting Zhou ◽

...

Keyword(s):

Land Use ◽

Ecosystem Services ◽

Urban Expansion ◽

Critical Factor ◽

Vital Role ◽

Water Yield ◽

Rapid Urbanization ◽

Invest Model ◽

Integrated Valuation ◽

The Impact

Land use and land cover change is a critical factor of ecosystem services, while water yield plays a vital role in sustainable development. The impact of urban expansion on water yield has long been discussed, but water yield change resulting from cropland protection is seldom concerned. Therefore, this paper aims to investigate the impacts of cropland protection on water yield by comparing the water yield in two cropland protection scenarios (i.e., Strict Cropland Protection scenario and No Cropland Protection scenario). Specifically, the LAND System Cellular Automata for Potential Effects (LANDSCAPE) model was employed to simulate land use maps in the two scenarios, while Water Yield module in the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) model was used to calculate water yield. The results show water yield would increase by 8.7 × 107 m3 in the No Cropland Protection scenario and 9.4 × 107 m3 in the Strict Cropland Protection scenario. We conclude that implementation of strict cropland protection in rapid urbanizing areas may cause more water yield, which is also a prerequisite of potential urban flooding risk. This study throws that it is not wise to implement strict cropland protection policy in an area of rapid urbanization.

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Interaction Analysis of Urban Blue-Green Space and Built-Up Area Based on Coupling Model—A Case Study of Wuhan Central City

Water ◽

10.3390/w12082185 ◽

2020 ◽

Vol 12 (8) ◽

pp. 2185 ◽

Cited By ~ 1

Author(s):

Jing Wu ◽

Shen Yang ◽

Xu Zhang

Keyword(s):

Landscape Pattern ◽

Green Space ◽

Interaction Analysis ◽

Central City ◽

Urban Expansion ◽

Landscape Fragmentation ◽

Coupling Model ◽

Coordinated Development ◽

Rapid Urbanization ◽

Development Level

Urban “blue-green” space is the basic element of urban natural ecological space. The rapid urbanization process has a significant impact on the pattern of urban blue-green space and seriously threatens the urban ecological environment. It is of great significance for urban ecological protection and sustainable development to study the change in characteristics of blue and green space during urban expansion. In this paper, a comprehensive method of remote sensing image, landscape pattern analysis, sector analysis, and coupling analysis is applied to analyze the spatio-temporal evolution characteristics and coordinated development level of the blue-green space and built-up area in central Wuhan from 1987 to 2018. The results showed that the land use and landscape pattern in the central city of Wuhan underwent a drastic change process, and the dominant change was the occupation of blue-green space by urban built-up areas, which led to the increase of landscape fragmentation and the decrease of heterogeneity. Urban green space is gradually marginalized and concentrated in local areas. The blue space has an obvious blocking effect on the expansion of the built-up area, and its spatial pattern tends to be stable gradually. In addition, the coupling degree between urban blue-green space and urban built area presents an inverted U-shape, and the coordinated development level among the three has entered a stage of moderate imbalance. It is urgent to strengthen the protection of blue-green space, curb the disorderly expansion of cities, and improve the quality of urban development.

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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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Detection of City Integration Processes in Rapidly Urbanizing Areas Based on Remote Sensing Imagery

Land ◽

10.3390/land9100378 ◽

2020 ◽

Vol 9 (10) ◽

pp. 378

Author(s):

Zihao Zheng ◽

Zhifeng Wu ◽

Yingbiao Chen ◽

Zhiwei Yang ◽

Francesco Marinello

Keyword(s):

Remote Sensing ◽

Light Intensity ◽

Infrared Imaging ◽

Urban Expansion ◽

Geographical Location ◽

Landsat 8 ◽

City Development ◽

Rapid Urbanization ◽

Boundary Area ◽

South Central

Since China’s reform and development commenced, in the context of rapid urbanization and coordinated regional development, Chinese cities with a close geographic proximity and social ties have gradually formed an integrated city development model. As a new phenomenon in China’s urbanization process, existing research on China’s integrated cities mainly focuses on typical case studies, and most research has been limited to literature reviews and theoretical analyses. The growing application of remote sensing technology in urbanization research in recent years has provided new opportunities for the analysis of city integration. Therefore, based on multi-spectral Landsat-8 and nighttime light images (SNPP/VIIRS, Suomi National Polar-orbiting Platform/Visible Infrared Imaging Radiometer Suite), this paper selects four of the most representative integrated cities with different backgrounds in China to analyze the land-use conversion, plot light fluctuation, and light gravity center shift in the boundary zone between cities. The results show that (1) Guangfo has the highest level of integration and urban expansion is mainly concentrated in the south-central part of the boundary area; (2) Guanshen’s level of integration is second to Guangfo’s and is mainly concentrated in the west; (3) HuSu’s integration is still in the initial stage and its increase in light intensity lags behind the expansion of building land during the study period; (4) although the light intensity and building land area increased significantly during the study period in Xixian, the overall development level of Xixian still lagged behind coastal cities due to the restriction of its geographical location. Our application results expand the data sources for integrated city research and the obtained results can potentially support decision-making and planning in the process of urban development.

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Spatio-temporal Patterns and Driving Forces of Urban Expansion in Beijing Central City Since 1932

Geo-information Science ◽

10.3724/sp.j.1047.2010.00428 ◽

2010 ◽

Vol 11 (4) ◽

pp. 428-435 ◽

Cited By ~ 14

Author(s):

Wenhui KUANG ◽

Quanqin SHAO ◽

Jiyuan LIU ◽

Chaoyang SUN

Keyword(s):

Driving Forces ◽

Central City ◽

Urban Expansion ◽

Temporal Patterns ◽

Spatio Temporal

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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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Carabid Beetle (Coleoptera: Carabidae) Response to Soil Properties of Urban Wastelands in Warsaw, Poland

Sustainability ◽

10.3390/su122410673 ◽

2020 ◽

Vol 12 (24) ◽

pp. 10673

Author(s):

Axel Schwerk ◽

Marzena Wińska-Krysiak ◽

Arkadiusz Przybysz ◽

Ewa Zaraś-Januszkiewicz ◽

Piotr Sikorski

Keyword(s):

Negative Impact ◽

Carabid Beetle ◽

Carabid Beetles ◽

Soil Parameters ◽

City Development ◽

Space Management ◽

Trade Offs ◽

Beetle Assemblages ◽

Trace Element Contamination ◽

The One

Urban wasteland is of special interest to city planners. However, to integrate such areas into city space management with consideration of nature conservation aspects, a sound assessment of their ecological potential is necessary. The aim of this paper was to analyze whether carabid beetle assemblages of the wastelands are affected by soil parameters, particularly trace element contamination. Therefore, we studied the carabid fauna in relation to selected soil parameters on 56 sampling plots situated in 24 wastelands located in the city of Warsaw (Poland). The results have confirmed our assumptions that the number of species, as well as the number of individual carabid beetles, are negatively affected by an increasing amount of pollutants in the soil. Particularly, the trace elements Pb, Cu, and Cd showed a significantly negative impact. The results are of value when it comes to the use of urban wastelands in the context of sustainable city development. Future use of urban wastelands will be faced with trade-offs between the use for public interests (e.g., housing space) and ecological interests. Phytoremediation and entomoremediation may be included in decontamination measures. The results of studies, such as the one conducted by us, may help to select the respective wastelands for certain purposes.

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Spatiotemporal Influence of Land Use/Land Cover Change Dynamics on Surface Urban Heat Island: A Case Study of Abuja Metropolis, Nigeria

ISPRS International Journal of Geo-Information ◽

10.3390/ijgi10050272 ◽

2021 ◽

Vol 10 (5) ◽

pp. 272

Author(s):

Auwalu Faisal Koko ◽

Wu Yue ◽

Ghali Abdullahi Abubakar ◽

Akram Ahmed Noman Alabsi ◽

Roknisadeh Hamed

Keyword(s):

Land Use ◽

Land Cover ◽

Land Surface ◽

Urban Expansion ◽

Urban Heat Islands ◽

Sustainable Land Use ◽

Land Use Land Cover ◽

Urban Centers ◽

Rapid Urbanization ◽

Urban Heat

Rapid urbanization in cities and urban centers has recently contributed to notable land use/land cover (LULC) changes, affecting both the climate and environment. Therefore, this study seeks to analyze changes in LULC and its spatiotemporal influence on the surface urban heat islands (UHI) in Abuja metropolis, Nigeria. To achieve this, we employed Multi-temporal Landsat data to monitor the study area’s LULC pattern and land surface temperature (LST) over the last 29 years. The study then analyzed the relationship between LULC, LST, and other vital spectral indices comprising NDVI and NDBI using correlation analysis. The results revealed a significant urban expansion with the transformation of 358.3 sq. km of natural surface into built-up areas. It further showed a considerable increase in the mean LST of Abuja metropolis from 30.65 °C in 1990 to 32.69 °C in 2019, with a notable increase of 2.53 °C between 2009 and 2019. The results also indicated an inverse relationship between LST and NDVI and a positive connection between LST and NDBI. This implies that urban expansion and vegetation decrease influences the development of surface UHI through increased LST. Therefore, the study’s findings will significantly help urban-planners and decision-makers implement sustainable land-use strategies and management for the city.

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