Impact Of Urbanization Research Articles

Soil source, not the degree of urbanization determines soil physicochemical properties and bacterial composition in Ningbo urban green spaces

Urban green spaces provide multiple ecosystem services and have great influences on human health. However, the compositions and properties of urban soil are not well understood yet. In this study, soil samples were collected from 45 parks in Ningbo to investigate the relationships among soil physicochemical properties, heavy metals and bacterial communities. The results showed that soil dissolved organic matter (DOM) was of high molecular weight, high aromaticity, and low degree of humification. The contents of heavy metals were all below the China's national standard safety limit (GB 3660–2018). The bioavailability of heavy metals highly correlated with soil pH, the content of DOC, the fluorescent component, the degree of humification and the source of DOM. The most abundant genera were Gemmatimonadaceae_uncultured, Xanthobacteraceae_uncultured, and Acidothermus in all samples, which were related to nitrogen cycle and bioavailability of heavy metals. Soil pH, bioavailability of Zn, Cd, and Pb (CaCl2 extracted) were the main edaphic factors influencing bacterial community composition. It should be noted that there was no significant impact of urbanization on soil physicochemical properties and bacterial composition, but they were determined by the source of soil in urban green spaces. However, with the passage of time, the effect of urbanization on urban green spaces cannot be ignored. Overall, this study provided new insight for understanding the linkage among soil physicochemical properties, heavy metals, and bacterial communities in urban green spaces.

Dynamics of respiratory infectious diseases under rapid urbanization and COVID-19 pandemic in the subcenter of Beijing during 2014–2022

ObjectiveThe study analyzed the impact of urbanization on epidemiological characteristics of respiratory infectious disease in Tongzhou District, Beijing during 2014–2022 to provide reference for prevention and control priorities of respiratory infectious diseases during the innovative urbanization process in China. MethodsThe incidence data of notifiable respiratory infectious diseases (NRIDs) in Tongzhou Beijing during 2014–2022 were summarized. The trend of incidence rate was analyzed by Joinpoint regression model, and entropy method was performed to construct the comprehensive index of urbanization (CIU) and generalized linear model was used to analyze the influence of CIU on the incidence rate of respiratory infectious diseases. ResultsTotally 72616 NRIDs cases were reported in Tongzhou District during 2014–2022, and the incidence rate of NRIDs was higher during 2017–2019 (153/100 000) than during 2014–2016 (930/100 000) and during 2020–2022 (371/100 000), respectively (both P < 0.001). The CIU constantly increased with slight fluctuation in 2016 and 2018, respectively. The incidence rate of NRIDs showed an increase along with the CIU during 2014–2019 (r = 0.95, P = 0.004), while the incidence rate's tendency was interrupted by COVID-19 during 2020 with slight decrease in 2020–2021 and rebounded in 2022. For the patients aged <15 years, the incidence rate of NRIDs revealed a very sharp rise at the urbanization period without COVID-19 pandemic compared with that under pre-urbanization period (RR = 7.93, 95 % CI 7.63−8.24), and dropped off to the similar level as of pre-urbanization period when COVID-19 pandemic spread. ConclusionsUrbanization process may increase the incidence of NRIDs but constrained by COVID-19. Certain measures should be taken to prevent and control the effects by urbanization process, such as good natural environment with less population density, ecological environment with good air quality, promoted hand hygiene, mask wearing, keeping interpersonal distance, vaccination, media publicity for NRIDs’ prevention and control.

The urban sea: Cribra orbitalia, porotic hyperostosis, linear enamel hypoplasia, and sinusitis in three diachronic urban sites from the Dutch province of Zeeland (1030–1800 CE)

AbstractUntil the 17th century, the Dutch coastal region of Zeeland ranked among Europe's most urbanized areas, driven by thriving international trade networks. People living in this time of flourishing economy benefitted enormously from it in terms of employment opportunities and working conditions, which were reportedly better than in the rest of the Low Countries. However, the rapid growth of Zeeland's urban centers likely presented increasing challenges for the population in terms of accessing essential resources, including food, clean water, and housing. In the 19th century, Zeeland's economy ultimately faced a significant downturn due to the decline in the maritime trade, leading to a substantial reduction in its urban population. Examining patterns of urbanization and economic histories that differ from the commonly studied thriving industrial contexts in bioarcheological research, as exemplified by Zeeland, is a crucial yet relatively underexplored facet in our efforts to understanding the human past. To address this gap, this study investigates the impact of urbanization on the health of Zeeland's inhabitants over time by analyzing nonspecific stress markers (i.e., cribra orbitalia, porotic hyperostosis, and linear enamel hypoplasia) and chronic maxillary sinusitis in a sample of 246 individuals from three urban sites dating from 1030 to 1800 CE. Our analysis of skeletal remains reveals significant differences in the prevalence of porotic hyperostosis, linear enamel hypoplasia, and sinusitis between the medieval and post‐medieval periods. These findings suggest that de‐urbanization and economic decline adversely affected the health and well‐being of the populations under study, influenced by factors such as working conditions and food availability. This study provides a new perspective on bioarcheological approaches to urbanization, shedding light on the intricate realities of urbanization in Zeeland and offering important insights into its complexities.

The impact of urbanization and economic growth on carbon dioxide emission in sub-Saharan African countries: a perspective from the spatial-temporal approach.

Sub-Saharan Africa (SSA) is seeing exceptional urbanization and economic expansion rates. Therefore, the STIRPAT (Stochastic Impacts by Regression on Population, Affluence, and Technology) parameters and the spatial econometric framework are used in this work to examine the influence of economic growth and urbanization on SSA's CO2 emissions. Likewise, to determine the spatial effect and understand how factors influence the spatial dependence of carbon emissions, the study builds a spatial Durbin model (SDM). In line with the findings, the spatial correlation test revealed the spatial correlations across various countries. This indicates that the changes in sub-Saharan African country's CO2 emissions impacted nearby countries and the countries themselves. Additionally, the findings reveal that, in the SSA's countries, urbanization, economic growth, industrial structure, trade, and population, excluding energy intensity, which failed the significant test, all positively influence CO2 outflows, in line with the spatial econometric model's findings. Thus, energy intensity shares an adverse impact on carbon emissions. As an outcome, energy intensity reduces carbon dioxide emissions in nearby nations and the entire region. Thus, the study recommends that policymakers account for the effects of spatial spillover when establishing low-carbon policies, encouraging a low-carbon lifestyle, promoting environmentally friendly technologies, and improving regional collaboration.

Impact of Urbanization on the Vegetation Dynamic in Tama River Basin

Impact of Urbanization on the Vegetation Dynamic in Tama River Basin

The Impact of Urbanization on Environmental Quality in Ecologically Fragile Areas: Evidence from Hengduan Mountain, Southwest China

The impact of urbanization on the environmental quality of ecologically fragile areas has long been ambiguous. With a focus on the human–environment interaction in 95 counties of Hengduan Mountain, an ecologically fragile region in southwestern China, in this study, we clarify the impact and mechanism of urbanization on environmental quality through the environmental regulation effect, using econometric models and county-level panel data from 2010 to 2019. The results of this study show that: (1) urbanization and environmental regulation have increased over this 10-year period within the study area and regional differences in environmental quality have decreased; (2) urbanization significantly contributes to environmental quality, with heterogenous effects on different environmental elements—increasing the proportion of wetlands and green areas per capita but suppressing vegetation coverage and production efficiency; and (3) environmental regulation is an important mechanism for urbanization to improve environmental quality; however, there are negative externalities on neighboring areas. The results of this study show that urbanization and environmental quality are not always mutually exclusive, thus providing a reference for the development of pro-environmental urbanization to improve sustainable development in ecologically fragile areas.

Inducing Populace Rapport Around Bellandur Lake in Order to Revitalize and Protect Its Natural Environment

Urbanization is a global phenomenon with profound consequences for the environment. As cities expand and populations grow, the impact of urbanization on natural resources, including freshwater bodies, becomes increasingly evident. Bellandur Lake, once a pristine natural asset, now faces severe environmental challenges, including pollution and encroachment. This research study explores the imperative need to induce rapport within the local populace to revitalize and protect the natural environment of Bellandur Lake. Amidst ongoing trends, Bangalore grapples with a dire water scarcity. This research is crucial now, promising broader insights and solutions. The research begins with a comprehensive assessment of the current state of the lake, encompassing water quality, ecosystem health, and surrounding environmental conditions. It identifies the multifaceted environmental threats and challenges confronting the lake and investigates the existing level of public awareness and perception regarding these issues. Furthermore, the research study delves into an examination of existing policies and governance structures related to the lake and provides recommendations for their enhancement to ensure comprehensive environmental conservation. It also establishes a monitoring and evaluation framework to assess progress and sustainability in lake revitalization. This research study not only serves as a comprehensive guide to the revitalization and protection of Bellandur Lake but also as a model for inducing populace rapport around critical natural assets elsewhere. By nurturing a strong connection between the local populace and the lake, it is aimed to ensure the long-term well-being of both the ecosystem and the community.

Urbanization and Heat Island Effect: A Comparative Study in Egypt

Purpose: The aim of the study was to analyze urbanization and heat island effect: a comparative study Methodology: This study adopted a desk methodology. A desk study research design is commonly known as secondary data collection. This is basically collecting data from existing resources preferably because of its low cost advantage as compared to a field research. Our current study looked into already published studies and reports as the data was easily accessed through online journals and libraries. Findings: A comparative study in Egypt investigated the impact of urbanization on the heat island effect. Findings indicated that highly urbanized areas, like Cairo, exhibited more pronounced heat island effects due to extensive infrastructure and limited vegetation. Rapid urbanization and land use changes were identified as significant contributors to increased heat island intensity. The study emphasizes the importance of urban planning strategies to mitigate these effects and calls for further research to better understand the urbanization-heat island relationship in Egypt. Unique Contribution to Theory, Practice and Policy: Theory of urban heat island effect, theory of land use and land cover change &amp; theory of socioeconomic drivers of urbanization may be used to anchor future studies on urbanization and heat island effect: a comparative study. Integrate green spaces, such as parks, urban forests, and green roofs, into urban planning and design to mitigate the heat island effect. Implement urban planning regulations and building codes that mandate the incorporation of heat mitigation measures in new developments and retrofits.

Optimizing the deployment of LID facilities on a campus-scale and assessing the benefits of comprehensive control in Sponge City

Rapid and intense urbanization has brought a wide range of serious issues like flooding and water pollution, which have become a great concern in a lot of cities. In response to these problems, Sponge City (SPC) has emerged as a potential solution. This study utilized the Stormwater Management Model (SWMM) to simulate urban runoff and determine an optimal combination of Low Impact Development (LID) strategies for reconstructing the study area. Upon analyzing the existing rainwater drainage system and revealed that it could only meet the design return period of 2-years, and identified the vulnerable flood-prone area and the maximum overflow node. After comprehensive consideration of various factors, the sponge reconstruction scenario selected four LID facilities combination: Porous pavement, Rain garden, Sunken green belt, and Green roof. Results indicated that when P = 1-yr, 5-yr, 10-yr and 20-yr, the total runoff in the LID scenario decreased by 43.91 %, 43.93 %, 45.95 % and 47.11 %, respectively. LID facilities substantially mitigate stormwater runoff and peak flows during moderate to light rainfall events. These LID facilities prove effective in reducing pollutant concentrations (reduction rate is all over 42 %), with notable reductions in Chemical Oxygen Demand (COD) and Suspended Solids (SS). This paper offers valuable insights that can serve as a reference for the construction or renovation of SPC, shedding light on effective strategies and considerations for managing stormwater and mitigating the impact of urbanization.

Urbanization enhances channel and surface runoff: A quantitative analysis using both physical and empirical models over the Yangtze River basin

Urbanization has become an irreversible trend and is even more rapid in flood-prone area. However, the responses of both channel runoff and surface runoff to the urbanization and the underlying mechanisms still deserve more in-depth exploration within urban extents with limited data availability. Accordingly, we conducted a comprehensive quantitative analysis of the urbanization effects on channel and surface runoff from both statistical and model-based perspectives over three major urban agglomerations (i.e., Chengyu (CY), middle region of Yangtze River (MRYR), Yangtze River Delta (YRD)) in the Yangtze River Basin. The long-term high-resolution channel and surface runoff under different urbanization scenarios were simulated using both WRF-Hydro and SCS-CN models by integrating multiple remotely sensed, reanalysis, and in-situ datasets. Results demonstrated that the channel runoff increased by 4.4%, 5%, and 12.08% in CY, MRYR, and YRD urban agglomerations, respectively. Meanwhile, the urbanization also contributed to 30%, 21.4%, and 17.7% of the surface runoff changes in three urban agglomerations. Based on the high-resolution local climate zone (LCZ), our results highlighted that the high-rise and middle-rise buildings and compact-arranged regions were more prone to accumulating surface runoff and trigger flooding events due to the weaker infiltration capacity of land surface with the densely distribution of impervious surface. Further machine learning based investigation and case analysis also explored the potential influencing factors and mechanisms of the impact of urbanization on channel and surface runoff. Results in the current research show further evidence that policy makers of urban planning and management need to consider and ensure societal preparedness for extreme runoff and flooding events.

How urbanization shapes the ecosystem carbon sink of vegetation in China: A spatiotemporal analysis of direct and indirect effects

Rapid urbanization has led to extensive effects on the spatio-temporal patterns of the carbon sources and sinks in ecosystems. However, due to the lack of long-term continuous land use/cover change (LUCC) data, there has been limited discussion on the spatio-temporal impacts of urbanization on carbon sources/sinks and the non-linear characteristics of urban changes over time. This study focused on the impact of urbanization on vegetation net ecosystem productivity (NEP) in 31 provincial capital cities in China from 1990 to 2019, using land use change data and NEP indicators, to analyze the change patterns and response modes of urbanization intensity and NEP. The study found that: (1) During the period of 1990–1995, almost all cities in China experienced a turning point of urbanization rate from decreasing to increasing, while after 2000, the urbanization rate declined significantly; (2) Climate background affects the negative impact of urbanization on NEP, especially in warm and humid climate background, while the direct impact of urbanization on vegetation is more significant; (3) Overall, urbanization in China aggravated the negative impact of urbanization on NEP from 1990 to 2019, especially in cold and arid climate background, which would further exacerbate the negative impact of urbanization. This study helps us better understand the impact of Chinese urbanization on ecosystem carbon sinks and mitigating the carbon emissions pressure of urban environments.

Assessment of heavy metal and other chemical pollution in Lake Tana along urban peripheries, Ethiopia

Abstract This study investigates the heavy metals (HMs) and other constituents in Lake Tana around the Gulf of Bahir Dar City. The water sample was collected from areas receiving drainage water and a reference sample was collected from areas away from the urban impact, both during dry and wet seasons. Pollution sources and levels were determined using pollution indices and GIS spatial analyses. All in situ parameters were in the recommended range of the USEPA aquatic and WHO drinking water guidelines. The level of dissolved P was recorded between 0.03 and 0.9 mg/l and the level of N-NO3 ranged from 0.05 to 1.01 mg/l indicating that the limits were above USEPA aquatic criteria. The HMs varied from 0.08 to 2.85 mg/l for Cu, 0.10 to 1.60 mg/l for Fe, 0.04 to 0.22 mg/l for Cr, and Mn was below detection. Cr and Fe were above the aquatic and drinking water guideline limit. Spatially, pollution was more significant in areas receiving drainage. Also, except Cu and Fe, other parameters were higher in the rainy season indicating storm runoff pollution. The overall pollution indices of water quality status, such as water quality index 63, heavy metal pollution index 3.1, and nutrient pollution index 4.7, indicated the quality level of water to be alarming. Therefore, comprehensive regulatory and waste management practices are needed.

The Impact of Multi-Dimensional Urbanization on CO2 Emissions: Empirical Evidence from Jiangsu, China, at the County Level

Understanding the underlying mechanism of how various dimensions of urbanization affect CO2 emissions could be helpful for achieving the goal of low-carbon cities in China. However, previous research has seldomly examined this relationship granularly in economically developed regions at the micro level, nor did they examine the mediating effects of economic development, industrial structure, and coal consumption. Using the panel dataset of 80 counties from 2002 to 2021 at the county level in Jiangsu, China, this study investigates the direct and indirect effects of population, economic, and land urbanizations on CO2 emissions in Jiangsu province and examines the regional heterogeneity. The findings indicate that population and economic urbanization have positive impacts on CO2 emissions, whereas land urbanization has insignificant effects. This finding is supported by various robustness tests. Population and economic urbanizations are found to have significantly positive impacts on CO2 emissions in the southern and northern Jiangsu regions, whereas none of the three dimensions are significant in the middle Jiangsu region. Economic urbanization contributes the most to CO2 emissions in southern Jiangsu. In addition, our results indicate that multi-dimensional urbanizations affect CO2 emissions through the mediating roles of economic development, industrial structure, and coal consumption. Our analysis shed some insights into the nuanced relationship between multi-dimensional urbanization and carbon emissions, which could contribute to sustainable urban transformation.

Unveiling health dynamics: Exploring the impact of CO2 emissions, urbanization, and renewable energy on life expectancy and infant mortality in SAARC countries (1990–2022)

AbstractThis study examines the intensifying threat to public health caused by increased CO2 emissions from energy and modern urbanization. In this connection, we focused on SAARC countries from 1990 to 2022. The study explores the dynamic association among urbanization, CO2 emissions, renewable energy, and key health indicators, namely life expectancy and infant mortality. It offers nuanced insights by highlighting the requirement for sustainable policies to meet health challenges associated with CO2 emissions and urban development in SAARC economies. To achieve the study objectives, the authors utilized panel auto regressive distributed lag for assessing short‐term and long‐run effects, and the method of moments quantile regressions to check these effects across different quantiles. The empirical results underscore the positive impact of renewable energy, urbanization, GDP, and industrialization on life expectancy. Conversely, CO2 emissions exhibit a detrimental impact on life expectancy, leading towards numerous diseases in both the short and long term. Notably, in the case of infant mortality, the study discloses that renewable energy, urbanization, GDP, and industrialization negatively affect infant mortality, while CO2 emissions positively impact infant mortality in both short and long‐run scenarios. Fully modified ordinary least squares and dynamic ordinary least squares further fortified our findings, supporting the results derived from panel auto regressive distributed lag and method of moments quantile regressions. The study's policy implications highlight the imperative for governments and policymakers to prioritize renewable energy and sustainable urbanization, mitigating the adverse health effects of CO2 emissions from non‐renewable energy sources. The study's findings further endorse a strategic shift towards renewable energy sources, positioning them as substitutes for conventional forms such as fossil fuels. Additionally, the emphasis is on planned and sustainable urbanization, facilitating improved access to health facilities and overall public health.

Integrating Green Infrastructure Distribution and Green Corridor Mapping with Proposed Green Trail Area and Wildlife-Human Conflict Using Remote Sensing-GIS Approach

Most people now prefer to live in cities, and the urban population has grown significantly. The decrement of urban green corridors causes an essential need for livability in highly populated areas. The needs of population health and sustainable city development are put under prolonged stress by the shortage of publicly accessible green infrastructure and its placement in inappropriate areas. The inventory of green corridor areas and the distribution of significant infrastructure are not fully understood, thus encouraging conflicts between residents and wildlife and increasing flood risk in their vicinity. Optical satellite images were required to (1) develop a green corridor (GC) map, (2) investigate the green infrastructure (GI) demand with the existing land use, and (3) propose new green trails (GT) in the Kuantan district using a geospatial approach. NDVI and site suitability analysis were carried out on Landsat OLI and Sentinel-2 MSI images, which were integrated with GIS tools to achieve all the objectives. A GC map has been developed, and five new proposed areas for GI development have been identified. Based on the results, 5 proposed green trails (3 long GTs, 2 short GTs) with a total length of 79.3 km are scattered in the Kuantan district at the most suitable site, identified using a geospatial approach. This study supports SDG 15: Life on Land, where green corridors reinforce biological connectivity, provide conducive space for high-populated areas, and minimize the negative impact of urbanization on the designed areas of GC, GI and GT in the developing city of Kuantan.

Spatial Heterogeneity Impacts of Urbanisation on Open Space Fragmentation in Hong Kong’s Built-Up Area

Rapid urbanisation has generated numerous environmental consequences, particularly regarding open space fragmentation. Open space fragmentation is the transformation of open space from a state of homogeneity, integration, and continuity to a state of heterogeneity, division, and incoherence. Nevertheless, one main obstacle to understanding this issue is how to address the spatial heterogeneity of the impact of urbanisation on open space fragmentation. Thus, this paper provides a comprehensive framework for the mechanistic associations between open space fragmentation and urbanisation in Hong Kong’s built-up area. The results illustrate that both open space fragmentation index and urbanisation index values are noticeably higher in dense urban areas. Land urbanisation, represented by the percentage of construction land in total land, has the highest explanatory power for spatial differentiation in open space fragmentation, followed by social and population urbanisation factors. Furthermore, the relational interrelations of open space fragmentation drivers are the bivariate and nonlinear enhancement interactions. Social urbanisation and land urbanisation have the strongest bivariate enhancement interaction for the use fragmentation form and the largest nonlinear enhancement interaction for the internal fragmentation form. Based on initial urban planning, open space fragmentation is an adaptation outcome of population, land, and social urbanisation factors, and this self-organisation phenomenon has been further emphasised in the historical process. These insights significantly enrich our understanding of how urbanisation affects open space fragmentation and provide valuable guidance for better open space strategies.

The battle for Central: ethnicity, urbanization and citizenship in Kenya’s 2022 general elections

ABSTRACT In Kenya’s 2022 general elections, presidential candidate William Ruto did something unusual – he dominated the vote in the heartlands of one of his main political rivals, President Uhuru Kenyatta. In turn, Ruto’s ability to win power by mobilizing support outside of his own Kalenjin community has led to speculation that the political power of ethnicity is waning. Drawing on surveys, economic and demographic analysis and interviews during the campaign in Central Kenya – a predominantly Kikuyu area and Kenyatta’s supposed political homeland – we cast doubt on this argument. Evidence from the campaign trail suggests that while structural changes within Kenyan society, including the emergence of a more urban, educated and critical electorate, played an important role in Ruto’s electoral success, it was also underpinned by historic ethnic allegiances, inter-group prejudice, and the use of ethnically-rooted clientelist strategies to build political networks. In particular, past campaigns saw Odinga depicted as an unsuitable leader based on his history, personality, and Luo ethnicity, generating formidable barriers to winning support. The implications of this argument extend beyond our understanding of Kenya to recent debates about the impact of urbanization and political socialization on political subjectivities and behaviour in Africa.

Does New Urbanization Support the Rural Inclusive Green Development under Domestic Circulation in China?

New urbanization is an endogenous driving force to enhance domestic circulation. Driving the development of rural industries with urbanization to achieve interactive symbiosis has become an important topic to promote the coordinated development of urban and rural green. Based on the panel data of 30 provinces in China from 2009 to 2021, this paper constructs an evaluation index system for new urbanization and rural inclusive green development, and uses principal component analysis and panel regression model to analyze the impact of new-type urbanization on inclusive green development in rural areas. The results of the study show the following: (1) Rural inclusive green development and new urbanization have been significantly improved during the study period, but there are significant regional differences. (2) The construction of the new urbanization significantly promotes rural inclusive green development, but there is significant spatial heterogeneity. This effect is more significant in the Eastern and Central regions. (3) Population urbanization, land urbanization, social urbanization, and environmental urbanization can effectively promote rural inclusive green development, but economic urbanization will have a negative impact on green development in the countryside during the study period. Therefore, it is necessary to further strengthen the leading role of central cities and urban agglomerations, to promote the countryside with the city and at the same time to combat environmental pollution and to create ecologically livable towns and villages. In addition, the government should strengthen top-level design, provide industrial support to backward areas, improve the spatial layout of urbanization, and promote the deepening of new urbanization.

Spatial and Temporal Changes in Supply and Demand for Ecosystem Services in Response to Urbanization: A Case Study in Vilnius, Lithuania

Intensification of urbanization is changing the supply capacities and demand levels of ecosystem services (ESs), and their mismatch has become a major problem for the sustainable development of urban areas. In this study, spatiotemporal changes of three ecosystem services (food provision, C sequestration, recreation) were quantified and imbalances between their supply and demand were identified in Vilnius County (Lithuania) in 2000–2020. The most significant land use transformation was the increase in forest and urbanized land at the expense of agricultural land. The lowest supply and the highest demand for food, carbon sequestration, and outdoor recreation were in the urban center. The urban land ratio had a negative impact on the provision of ecosystems’ services during the study period, most notably affecting food supply. Urbanization indicators—population density and urban land area—showed a negative relationship with the provision of ecosystem services. The balance of supply and demand changed during the 2000–2020 period—the growth of suburbs led to the distance of the supply areas from the city, and the area of the intense demand increased. The results of the study highlight the importance of spatial scale in determining the impact of urbanization on ecosystem functions.

High-resolution satellite images reveal the prevalent positive indirect impact of urbanization on urban tree canopy coverage in South America

Trees in urban areas act as carbon sinks and provide ecosystem services for residents. However, the impact of urbanization on tree coverage in South America remains poorly understood. Here, we make use of very high resolution satellite imagery to derive urban tree coverage for 882 cities in South America and developed a tree coverage impacted (TCI) coefficient to quantify the direct and indirect impacts of urbanization on urban tree canopy (UTC) coverage. The direct effect refers to the change in tree cover due to the rise in urban intensity compared to scenarios with extremely low levels of urbanization, while the indirect impact refers to the change in tree coverage resulting from human management practices and alterations in urban environments. Our study revealed the negative direct impacts and prevalent positive indirect impacts of urbanization on UTC coverage. In South America, 841 cities exhibit positive indirect impacts, while only 41 cities show negative indirect impacts. The prevalent positive indirect effects can offset approximately 48% of the direct loss of tree coverage due to increased urban intensity, with full offsets achieved in Argentinian and arid regions of South America. In addition, human activity factors play the most important role in determining the indirect effects of urbanization on UTC coverage, followed by climatic and geographic factors. These findings will help us understand the impact of urbanization on UTC coverage along the urban intensity gradient and formulate policies and strategies to promote sustainable urban development in South America.