Development Of Megacities Research Articles

Vertical distributions of tropospheric formaldehyde, nitrogen dioxide, ozone and aerosol in southern China by ground-based MAX-DOAS and LIDAR measurements during PRIDE-GBA 2018 campaign

As the development of megacities, combined air pollution has been of increasing concern in China, which is composed by primary pollution, such as Nitrogen dioxide (NO2), and the followed secondary pollution under certain meteorology circumstances and high concentration of precursors, such as tropospheric ozone, formaldehyde (HCHO) and fine particles. During PRIDE-GBA 2018 Campaign (Particles, Radicals, Intermediates from oxiDation of primary Emissions in Great Bay Area), we performed the high resolution vertical observations of pollution gases and aerosol, which are significant but scarce indexes in studying the mechanisms of tropospheric pollution, using remote sensing techniques. NO2 and HCHO column densities and vertical profiles are reconstructed from data of multi-axis differential optical absorption spectroscopy (MAX-DOAS). Tropospheric ozone profile and aerosol extinction are retrieved by the differential absorption light detection and ranging (LIDAR) system. In order to verifying the accuracy, we evaluated the consistency and reliability of MAX-DOAS and LIDAR measurements. The results showed reasonable agreement with in-situ and off-line observations at Canton Tower. A typical combined pollution process from Sep 29 to Oct 10 was analyzed in detail. More than 200 μg/m3 tropospheric ozone in this case was considered from the anthropogenic sources, including industry, power plant, residential and transportation. The high emission from local industry and polluted air transport from northeast brought the main precursors of this pollution process. The photochemical formation of tropospheric ozone was turned into a VOC-limited regime on polluted days.

Research of Socio-Spatial Aspect of Economic Security of Megacities: Risk Zones and Conflict Nodes

The article deals with the approaches to the analysis and assessment of the global city conflicts, used in the world and Russian practice, which allow conducting comparative studies of local areas in megacities, identifying risk areas and nodes of conflict. The study of economic security of megacities logically justifies the consideration of “conflict nodes” as threats and risks of a certain type, as a result of the analysis of “risk zones” and the conditions of contradictions in megacities, it is possible to use the tools of operational and strategic development management to improve the image of the city, its competitiveness and attractiveness. The Authors propose to consider the theme of “conflictness” of urban space in the context of monitoring the safe development of megacities. Evaluation of the level of safety and conflict within the megacity is based on statistical data and indicators of public opinion about achieved level of security. The results of the study are the clustering of St. Petersburg districts by conflict indicators and risk zones, the evaluation of adequacy of objective indicators of security of residence in a particular area and subjective assessments of residents. The article presents the results of assessing the level of conflicts in St. Petersburg as a global city, a comparative analysis of the subjective and objective component of the socio-spatial aspect of economic security. On the example of St. Petersburg, the Authors compare the identified clusters by risk zones and conflict nodes and illustrate the obtained result.

Megacity development and the demise of coastal coral communities: Evidence from coral skeleton δ15 N records in the Pearl River estuary.

Historical coral skeleton (CS) δ18 O and δ15 N records were produced from samples recovered from sedimentary deposits, held in natural history museum collections, and cored into modern coral heads. These records were used to assess the influence of global warming and regional eutrophication, respectively, on the decline of coastal coral communities following the development of the Pearl River Delta (PRD) megacity, China. We find that, until 2007, ocean warming was not a major threat to coral communities in the Pearl River estuary; instead, nitrogen (N) inputs dominated impacts. The high but stable CS-δ15 N values (9‰-12‰ vs. air) observed from the mid-Holocene until 1980 indicate that soil and stream denitrification reduced and modulated the hydrologic inputs of N, blunting the rise in coastal N sources during the early phase of the Pearl River estuary urbanization. However, an unprecedented CS-δ15 N peak was observed from 1987 to 1993 (>13‰ vs. air), concomitant to an increase of NH4+ concentration, consistent with the rapid Pearl River estuary urbanization as the main cause for this eutrophication event. We suggest that widespread discharge of domestic sewage entered directly into the estuary, preventing removal by natural denitrification hotspots. We argue that this event caused the dramatic decline of the Pearl River estuary coral communities reported from 1980 to 2000. Subsequently, the coral record shows that the implementation of improved wastewater management policies succeeded in bringing down both CS-δ15 N and NH4+ concentrations in the early 2000s. This study points to the potential importance of eutrophication over ocean warming in coral decline along urbanized coastlines and in particular in the vicinity of megacities.

Современные тренды стратегирования социально-экономического развития территории: пространственный аспект

The paper is devoted to the analysis of strategies for the socio-economic development of megacities of the Russian Federation in terms of the availability and elaboration of their spatial development issues. It has been established that at present there is no single understanding of the spatial development processes, these processes are understood and occur in different ways in each city. Modern versions of the strategies for socio-economic development of the largest cities of the Russian Federation are di-vided into three groups according to the elaboration of their spatial development aspects in this work. A proposal was formulated on the need to adopt common methodological approaches to the for-mation (development and updating) of socio-economic development strategies of megacities, including spatial development issues in order to unify and improve the effectiveness of strategic planning processes in the Russian Federation is formulated.

Changing of the characteristics of the labor potential in the transition to the technogenic society

The issues of changing the characteristics of labor potential in the transition to the technogenic society in the postindustrial community, which the processes of further urbanization and development of mega-cities are typical for, – have been examined. The technogenic society has been considered as the community, the basis of which is characterized by reducing dependence of a person on social groups, amplification of personality in creative work, changing of motivation pattern, high pace of social changes, alteration of interpersonal communication models. The movement of quantitative characteristics of labor potential is due to decreasing birth rates, the increasing share of older age groups, the downward changing of migration scale. Trends in the qualitative characteristics are pre-determined by the possibility of continuous learning and self-education. This in turn leads to changing of the situation in the labor market, where low-skilled workers are becoming non-competitive. High qualification fundamentally change an employee’s motivation: the significance of material incentives decreases, external motivation changes for the internal one, the meaningfulness of work, the independence of work performance, the responsibility for decisions taken, become an issue of the highest priority.The transition to the new culture of the technogenic society requires alteration of both professional and personal communications. The communication environment moves increasingly into the virtual world. However, a need is noted to lay emphasis upon the risks of the technogenic society, that relate to the increased scale of a person’s presence in the virtual world and to manage such risks. The risks of the technogenic society are connected with a person’s dependence on cyberspace, which has a negative impact on his or her mental health, and permanent using of electronic devices pre-determines risks of deteriorating his or her physical health. The digital transformation of the society requires the special attention to the safety of presence in cyberspace not only from the point of view of anonymizing of the personalized content, that identifies a particular person, but also taking into account the geolocation of his or her physical presence in the geographical coordinates of the real space. With the virtualization of all aspects of a person’s life, there are the increased risks of changing attitude towards the family values, forming the fundamental basis of the society’s functioning. The technogenic society contributes the risk of conscious single life, rejection family values. This risks will be catastrophic for the existence of humanity.

A Spatio-Temporal Autowave Model of Shanghai Territory Development

A spatio-temporal model of megacity development that treats the megacity as an active medium is presented. From our point of view, it is advisable to consider the process of urban ecosystem development from the standpoint of the theory of autowave self-organization in active media. According to this concept, the urban ecosystem is considered as interacting with each other’s natural and anthropogenic subsystems with significant heterogeneity of areas affected by human intervention and urban geobiocoenoses. The model is based on the general principles of active medium dynamics; therefore, it is universal for any object to be considered an active medium. The only difference when using the model to predict the development of urban ecosystems in countries with different socio-economic and political prerequisites is the variety of parameters included in the model, i.e., the activation parameter, the autowave process inhibitors, and the characteristic scales of the activator and inhibitor. The model was tested on the example of Moscow expansion in the period of 1952–1968 and showed good agreement with the map data. By means of the model, a prediction of Shanghai and surrounding territory development until 2030 was made.

The evolution of the ecological footprint and its relationship with the urban development of megacities in Western China: The case of Xi'an

Although China's western cities have developed rapidly in recent years, their ecosystems remain fragile. The conflict between urban development and environmental protection must be resolved to achieve the goal of sustainability. This study examines Xi'an as a case study of a megacity in Western China, calculating the city development index (CDI) and per capita ecological footprint (ef) from 2005 to 2016 to comprehensively calculate Xi'an's eco-efficiency. The E-C elasticity coefficient, which refers to the ratio of the rate of change in CDI to the rate of change in ef, is proposed to characterize the degree to which urban development responds to changes in the ef. The CDI and ef both showed an upward trend from 2005 to 2016. Xi'an's environmental efficiency has grown rapidly, and resource efficiency is the main factor driving its fluctuations in eco-efficiency. The energy consumption and pollution emissions are highly correlated with the CDI, and they are the main factors affecting the development of Xi'an. The relationship between CDI and ef is consistent with the law of diminishing marginal utility, the level of urban development rises and then decreases with the increase in ef.

Mega-city Planning Challenges——Taking Beijing as an Example

In the past 30 years, China has experienced development at full speed, andthe cities have expanded rapidly. There have been dozens of megacitieswith millions of people. Due to the lack of preparation of various factors,these cities will inevitably also have some urban diseases similar to thosein the mega-cities of the world. How to develop mega-cities, especiallyhow to ensure the sustainable development of mega-cities, such as Beijing, Shanghai, Guangzhou, etc., is a question that must be answered. Thispaper mainly discusses the challenges faced with city planning, especiallyfor mega-cities, taking Beijing as an example and analyzes from following aspects: institutional challenges, demographic challenges, and environmental challenges, and hopes to provide references for city planners

Modelling of sustainable development of megacities under limited resources

The paper is devoted to topical issues of urban planning in relation to megacities. We consider this issue taking into account the limitations of natural, communal, and social resources. The problem is especially acute for the overwhelming majority of the state capitals, as well as cities with historical heritage that are of great interest due to the rapid development of tourism and the high mobility of the population in the world. The authors formalize the problem of determining the optimal ratio of the volume of urban buildings intended for non-residents to the total housing stock. We conduct economic calculations to determine the quantitative indicators that can be used as the basis for administrative measures aimed at limiting the flow of people arriving with the intention of temporarily deploying in megacities.

Geotechnical and ecological foundations of the sustainable life cycle of the long-operated unique underground structures of the water disposal system in difficult ground conditions

Intensive development of megacities causes the need for sustainable operation of underground urban infrastructure facilities. In the special protection against man-made impact, long-operated unique underground structures of the water disposal system, which are related to facilities with an increased level of responsibility and danger, are needed. In the report, based on the experience of studying the operation of underground wastewater facilities in conditions of weak soils and intensive external static and dynamic impacts, there are proposed new methods for diagnosing their technical condition, modeling and monitoring of the joint work of the "underground structures aggregate of soil" system are implemented, forecasting and shaping conditions for its sustainable life cycle. Point and linear objects of the water canal of St. Petersburg are developed and implemented at unique (to a depth of 70 m.) geotechnology, providing simultaneous increase of bearing capacity, operational reliability and ecological safety of longoperated underground drainage facilities in difficult ground conditions with increasing man-caused impacts.

Urban development of the territory using environmental organizational and technological solutions

This article discusses issues aimed at determining the perception of modern urbanization. On the one hand, technological progress more and more enhances the environmental impact, thereby creating the prerequisites for the emergence of various environmental crises. On the other hand, it expands the possibilities of eliminating problems in this area. Therefore, there is a relationship between environmental impact, the level of economic development, and the level of development of civil society. Responsible attitude to the environment - an indicator of the high development of civilization - these are the aspects of the ecological development of megacities that urbanism deals with. Particular attention is paid to the need for an environmentally friendly modernization of modern urban spaces. The problem of reducing landscaped and forested areas in connection with the rapid increase in urban areas is considered. In order to clarify the latest urban development trends, innovative technologies and approaches to construction, as well as to the ecological organization of the urban environment, are considered.

Taxation, Property Rights and the Social Contract in Lagos

Major taxation reforms over the past decade have been interpreted as facilitating the transformation of Lagos: once widely seen as a city in permanent crisis, it is now seen by some observers as a beacon of megacity development. Most academic attention has focused on personal income taxation, which comprises the lion’s share of government revenue in Lagos. Less attention has been devoted to another crucial innovation over the same period – the Land Use Charge – and other forms of tax related to property. In this paper we show how the story of property taxation in Lagos since the early 2000s is important, not only in terms of the enormous increase in collection, but because of the ways in which property-related taxes have helped to support personal income taxation and to solidify the fiscal contract between state and society more broadly. Moreover, we explore how the payment of the Land Use Charge is interpreted by taxpayers, and how it is used alongside a plethora of other documents and processes to try and shore up fragile claims to property. In a context of intensely insecure tenure, particularly but not exclusively at the lower ends of the socio-economic spectrum, both taxation and other kinds of formal and informal payments play a key role in efforts to incrementally build and solidify property rights.

Impacts of temperature and precipitation on the spatiotemporal distribution of water resources in Chinese mega cities: the case of Beijing

Abstract Water shortages in China have hindered development of mega cities, especially Beijing. Assessing the impact of temperature and precipitation on water resources is important. This study analyzed spatiotemporal variations and impacts of temperature and precipitation on water resources in Beijing from 1956 to 2013, using statistical and spatial analysis. The results showed the following. (1) Temperature and precipitation affect water resources variously from region to region; their correlation in mountains is lower than in other areas. Precipitation redistribution caused by terrain reduces water resources. (2) The inter-annual variabilities of precipitation, temperature and water resources are different among five water resource divisions. Because of ‘rain-slope’, Beisanhe's precipitation is larger than others; Yongdinghe's precipitation is less than others due to ‘rain-shadow’; suffering from urban heat island effect, Beisihe and Daqinghe-plain's temperature is higher than others; Beisanhe and Beisihe's water resources are greater than others due to area differences. (3) Water resources are positively correlated with precipitation and negatively with temperature. (4) In recent years, precipitation and water resources decreased and temperature rose. Population growth, land use/land cover change, urbanization and pollution affected precipitation, temperature and water resources. Imported water cannot completely solve water shortages. With increasing water demand, precipitation and temperature will significantly influence water resources in Beijing.

Comparative assessment of circular economy development in China’s four megacities: The case of Beijing, Chongqing, Shanghai and Urumqi

Resources scarcity and environmental pollution in China negatively influence the country’s sustainable development. Circular Economy (CE), which established on the basis of “3R principals”, was adopted by the Chinese authorities as a national development strategy to reduce resource consumption and mitigate environmental pollution. After more than ten years’ implementation of CE strategy, it is of vital importance to investigate the progresses and current status of CE development in China, especially in those China’s megacities from both spatial and temporal perspectives, so as to identify the barriers of local CE development in megacities. To achieve such an objective, this study assesses the CE development in China’s four megacities during the last ten years by using one unified indicator system. Results indicate that significant disparities exist among China’s four megacities regarding both CE development index trajectory and CE internal structure. While all four megacities had significantly improved their CE development since 2005, megacities located in eastern China, namely Beijing and Shanghai, had better CE development performances than megacities from western China, namely Urumqi and Chongqing. With respect to the composition of CE development index, Beijing and Urumqi were doing better on balancing the development of CE’s four aspects, namely, resource consumption intensity (RCI), waste emission intensity (WEI), waste recycling and utilization rate (WRUR) and waste disposal level (WDL). In contrast, CE development in Chongqing and Shanghai was primarily attributed to the three aspects of RCI, WEI and WDL, and the WRUR aspects had contributed little to their CE development during the last ten years, indicating an unbalanced CE development status. Additional, Shanghai and Chongqing increased faster on annual average CE development index, and the growth of CE development index of Urumqi was the slowest among the four megacities. In order to promote the CE development performance in China’s four megacities, several measures have been proposed, including providing financial and technological support to Urumqi and Chongqing, promoting the recycling of reclaimed wastewater in Chongqing and Shanghai, supporting the application of integrated waste management, as well as encouraging the participation of local residents. This study could provide valuable reference for countries and regions that adopt CE as their development mode.

Entropy modeling of sustainable development of megacities

The entropy approach of modeling multidimensional stochastic systems is described. It is based on the system representation as a multidimensional random vector and on the use of its differential entropy as a mathematical model. The possibilities of using this entropy model are considered for problems of monitoring the state of complex systems, including megacities, regions and critical infrastructure. Examples of practical implementation of the model are presented for the study of the sustainable development of megacities and regional environmental protection systems.

Rapid development as a factor of imbalance in urban growth of cities in Latin America: A perspective based on territorial indicators

One of the main factors of imbalance in the urban development of cities is undoubtedly their growth rate. In this sense, one of the main characteristics of rural-urban migration phenomena that have shaped the development of megacities in developing countries has been the need to integrate a large mass of people through processes of rapid growth of its urban plot.In this paper the growth of five different cities in Latin America is analyzed from the perspective of the impact of these processes of transformation in the urban landscape, describing different levels of pathology in their development. Consumption of periurban space, cityscape misconfiguration, or the long-term sustainability of these processes of transformation are complex issues that need to be addressed from a rigorous and technical perspective. These variables will be subject to GIS evaluation and diagnosis by territorial indicators in order to establish patterns of behaviour.

INVESTIGATING THE ENRICHMENT OF A 3D CITY MODEL WITH VARIOUS CITYGML MODULES

Abstract. Recent developments in the massive 3D acquisition area made possible the generation of dense and precise 3D data, ranging from the representation of a simple building to a whole city. Nowadays, increasing urbanization, rapid growth of urban areas, and subsequently development of mega cities, are among the most important changes occurring worldwide. Therefore, developing techniques to manage these cities seems quite necessary. The aim of this paper is to investigate the enrichment of a 3D City Model with additional attributes, via appropriate CityGML Modules. The paper focuses on addressing the challenging issues that derive from a complex virtual 3D city modeling. More specifically, the paper investigates a complex built-up area, presenting and analyzing its constituting structures. Within this framework, the following CityGML modules are investigated: Bridge, Transportation Complex, CityFurniture, Land Use and Vegetation. To this purpose, the BIM-Standard software Trimble SketchUp and the data conversion tool FME are used. The processes of both modeling and converting are analyzed in detail. General conclusions and future research considerations are presented.

Quantitative evaluation of reactive nitrogen emissions with urbanization: a case study in Beijing megacity, China.

The rapid increase in anthropogenic nitrogen (N) load in urbanized environment threatens urban sustainability. In this study, we estimated the amount of reactive N (Nr) as an index of N pollution potential caused by human activities, using the megacity of Beijing as a case study. We investigated the temporal changes in Nr emissions in the environment from 2000 to 2012 using a multidisciplinary approach with quantitative evaluation. The Nr emissions presented slightly increasing during study period, and the annual emission was 0.19Tg N, mainly resulting from fuel combustion. Nevertheless, the Nr output intensity resulting from inhabitants' livelihoods and material production had weakened over the study period. The evaluation results showed that the environmental measures to remove Nr in Beijing were efficient in most years, suggesting that progress in mitigating the growth of the Nr load in this urban environment was significant. Further measures based on N offset are suggested that could help alleviate the environmental pressure resulting from anthropogenic Nr emissions. These could provide theoretical support for the sustainable development of megacities.

Local Climate Zone Study for Sustainable Megacities Development by Using Improved WUDAPT Methodology – A Case Study in Guangzhou

High density urban development in the past has not only changed natural landscape into artificial constructions and pavements, but also brought along many environmental problems like air pollution, urban heat island (UHI) and dust haze, which can affect the public health condition. There are limited applied urban climatic studies in urban planning and development. One of key reasons is there is a missing link between urban development and its corresponding impact on local climatic conditions. The concept of Local Climate Zone scheme has been developed to fit into this gap1. It introduces a standardized scientific way to describe the land cover and its thermal performance on the UHI. Since 2012, The World Urban Database and Access Portal Tools (WUDAPT) have been developed to call for international efforts and collaborations on world-wide LCZ studies. Its level 0 method can quickly collect urban morphology information and create LCZ maps2. However, it's time consuming to use WUDAPT to classify cities globally as WUDAPT is designed at city scale. This paper aims to improve the current methodology to classify more cities in a shorter time and also achieve a more accurate result. In this paper, Guangzhou is selected as case study since it has complex urban morphology and can represent as typical megacity in China. The study firstly reviews the concept of LCZ and WUDAPT. Secondly, the level 0 method of WUDAPT is used to initially classify LCZs of Guangzhou. For enhancing the efficiency of the existing WUDAPT, an improved methodology is developed to use WUDAPT to classify a region and extract the cities inside the region. Thirdly, the relevant quality checking work of the two methodologies is also conducted to detect the accuracy of the two methodologies. The improved outputs can be applied to numerical modellings and local planning implementation3. Because the future trend of urbanization in China is towards megacity development, the lessons learnt from the study can be applied to other megacities and regions for better climatic-spatial planning in future.

Sustainable Development in Megacities

The present paper aimed at determination of the sustainable development in the case of megacities. Although megacities presentextensiveopportunities for employment and investment, they cannot be considered without their own threats. The threats can be regarded in different contexts, such as social, economic, and ecological dimensions. Therefore, a well recognition of principles of sustainable development can deliver fruitful solutions in order to avoid potential hazards in the process of urbanization, notably in the case of megacities, and find a procedure to best consolidate sustainability into the current and future megacities. DOI: 10.5901/mjss.2015.v6n2s1p668