A Scheme for a Sustainable Urban Water Environmental System During the Urbanization Process in China

Urbanization is a potential factor in economic development, which is a main route to social development. As the scale of urbanization expands, the quality of the urban water environment may deteriorate, which can have a negative impact on sustainable urbanization. Therefore, a comprehensive understanding of the functions of the urban water environment is landscape, culture, and economy. Furthermore, a the urban water environment, which is associated necessary, including its security, resources, ecology, deep analysis is required of the theoretical basis of with geographical location, landscape ecology, and a low-carbon economy. In this paper, we expound the main principles for constructing a system for the urban water environment （including sustainable development, ecological priority, and regional differ- ences）, and suggest the content of an urban water environmental system. Such a system contains a nat- ural water environment, an economic water environment, and a social water environment. The natural water environment is the base, an effective economic water environment is the focus, and a healthy social water environment is the essence of such a system. The construction of an urban water environment should rely on a comprehensive security system, complete scientific theory, and advanced technology.

Problems on the application of geographic information systems to urban environmental management

Geographic information systems (GIS) are a widely used tool in urban planning and management. More and more cities and decision-makers require its attributes of promptness, precision and visualization. But the application of GIS in urban environmental management is still a new field and relevant researches are getting on tardily. As a subsystem of GIS, an urban environmental management geographic information system (UEMGIS) should be a complex multi-discipline and multi-objective tool to perform quantitative multi-dimension analysis and to transfer the results into an expression legible to an ordinary user. It should be a dynamic system of prompt functions based on upgradable databases, and be composed of many subsystems respectively specialized in items about water, air, waste and noise as well as relative standards and regulations. However, existing UEMGISs mostly rely on the basic GIS too much to design the actual requirements of applications and managements in themselves, and the unavailability of sufficient fundamental data has retarded their improvement. In the design of a UEMGIS, the standardization of data classification should be taken into consideration to make the data exchangeable and shareable among its subsystems and within every subsystem, and the applicable error limits for input data should be defined in accordance with the user抯 required precision of data out. Data acquisition can be easy and quick if remote sensing, global positioning system (GPS) and other technologies are combined with GIS. Rapidly progressing information technologies have been giving a bright prospect for the melioration of UEMGIS that will have great potential and wide application in environmental conservation.

The Multi-Scale Numerical Modeling System for Research on the Relationship between Urban Planning and Meteorological Environment

Considering the urban characteristics, a customized multi-scale numerical modeling system is established to simulate the urban meteorological environment. The system mainly involves three spatial scales: the urban scale, urban sub-domain scale, and single to few buildings scale. In it, different underlying surface types are employed, the building drag factor is used to replace its roughness in the influence on the urban wind field, the effects of building distribution, azimuth and screening of shortwave radiation are added, and the influence of anthropogenic heating is also taken into account. All the numerical tests indicate that the simulated results are reasonably in agreement with the observational data, so the system can be used to simulate the urban meteorological environment. Making use of it, the characteristics of the meteorological environment from the urban to urban sub-domain scales, even the among-buildings scale, can be recognized. As long as the urban planning scheme is given, the corresponding simulated results can be obtained so as to meet the need of optimizing urban planning.

ENVIRONMENTAL SUSTAINABILITY AND SCENARIOS OF URBANIZATION IN ARID AREA——A Case Study in Wuwei City of Gansu Province

Based on data of questionnaire and field survey and two developing models of Business As Usual (BAU) and the Intensive Urbanization (IU), this article, taking Wuwei City, a medium size city and typical oasis arid area in Gansu Province with very vulnerable and sensitive natural environment but long history of oasis economy, as an example, evaluated the sustainability of its environment and analyzed the scenarios of Wuwei’s household energy consumption, waste discharge in transportation industry, primary industry, secondary industry, tertiary industry, by the integration of the systematical dynamics model Stella and Polestar language to simulate the future development of the research area. The results showed that, first, the developing model of IU was propitious to Wuwei City named for oasis economy and vulnerable natural environment. The strategy of "Intensive Urbanization" can change the structure of energy utilization, and improve the efficiency of energy utilization. Second, the proportion of domestic energy consumption will decrease with industrialization and economic development, while that of tertiary industry, secondary industry and transportation will gradually grow up according to strategy of "Intensive Urbanization". Third, the Wuwei City is facing a severe eco-environmental crisis under the conventional patterns of development and a better future under a sustainable urbanization scenario, in the next 10 to 20 years. The different developing trends were clarified and the relative countermeasures were put forward for the policy makers according to the driving forces.

ANALYSIS ON THE SPATIAL DISTRIBUTION VARIATION CHARACTERISTIC OF URBAN HEAT ENVIRONMENTAL QUALITY AND ITS MECHANISM——A Case Study of Hangzhou City

Urban heat environmental quality (UHEQ) is affected by the interacting of weather condition and underlying surface framework of urban area. In the last two decades, many researchers from domestic and overseas have studied many problems at the aspect of urban heat environment such as urban heat islands, urban air temperature and their relation with urban land cover, city population, air pollution etc. In the recent years, Hangzhou, acting as a center city of Zhejiang Province in China, its urbanization quantum and quantity have both changed greatly, in particular, representing as business affairs building, resident real property and all kinds of specialty market having arisen in built-up zone. Based on Landsat TM images data in 1991 and 1999, urban underlying surface temperature value and Normalized Difference Vegetation Index (NDVI) were calculated using image interpreting and supervised classification technique by remote sensing software ERDAS image 8.4. The relation model between urban underlying surface temperature (UUST) and urban air temperature was setup according to the certain correlation pattern. Reference to the relational standard of assessing human comfort and other meteorology data of Hangzhou City in summer, the spatial distribution characteristic and the spatial variation degree of human comfort of heat environmental quality are estimated and mapped on a middle scale, that is, in six districts of Hangzhou City . Then the paper reveals the main characteristic of spatial variation from 1991 to 1999. Lastly, the change mechanism is analyzed and discussed from the viewpoint of city planning, construction and environmental protection.

Establishment and Application of Urbanization Strategic Environ-mental Assessment Integration Technology System

Urbanization strategic environmental assessment (SEA) is an effective instrument to enhance the harmo-nious development of urban complex system, integrating of environment and development in decision-making. Ur-banization strategic environmental assessment integration technology system (SEA-ITS) is composed of "3S" (RS, GIS and GPS), environmental expert system and environmental model system, coupling with appropriate SEA working process closely. In this paper, the structure and components of SEA-ITS are analyzed based on Chinese characteristics, meanwhile methods to fulfill the following system functions are discussed: urbanization SEA in-quiring, analysis, discrimination, assessment, prediction, decision-making and output. Moreover, methods and tech-nologies employed in different urbanization SEA hierarchies are summarized. As a case study, urbanization SEA-ITS is applied in Changchun City to solving complex real problems. Methods such as system dynamics and grey cluster are adopted to achieve the environmental impact assessment on the eco-industrial system planning. It is revealed that the system designed is capable of reflecting the dynamic behavior of eco-industrial system under different sce-narios, meanwhile accomplishing strategy optimization and supplying scientific reference. The 4th strategy, namely concerning on economy increase and its interaction with science, technology and environment progress, would have the best efficiency. Further, more attention should be paid to the secondary development of integration techniques and function modification system of urbanization SEA-ITS.

Study on urban water environmental support capacity

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Analysis of Existing Problems and Treatment Methods of Urban Environmental Monitoring

With the rapid development of the city,the concept of ecological environment has been integrated into everyone’s heart.In the new era,people also have higher requirements for the quality of living environment.However,at this stage,with the development of urbanization and industrialization,the problem of environmental pollution has become more and more serious.Therefore,we must do a good job in urban environmental monitoring,pay attention to the protection of urban environment,design and implement effective governance methods,so as to improve the quality of environmental governance.This article analyzes the problems in urban environmental monitoring,and formulates reasonable treatment methods and suggestions.

Coping with Multi-scale Climate Change:Study on the Application of Urban Environmental Climate Maps of Stuttgart,Germany

The development of modern cities has brought about tremendous changes in the climate environment.Faced with complex climate conditions,research on multi-scale climate change in cities is of great significance.The urban environmental climate maps and the application of climate atlas tool in Stuttgart,Germany were studied,and the multi-scale application of urban environmental climate maps in Stuttgart,Germany was summarized through the analysis of the pre-planning,current construction situation,and landscape reconstruction of the German"Stuttgart 21"plan case.Besides,other important measures to cope with climate change in German were proposed,and finally multi-scale practical strategies to cope with urban climate and environment were summarized to provide ideas and methods for improving China’s future urban climate environment.

Planning and Orientation Analysis of Urban Environmental Landscape Aesthetic Value

Landscape is people’s evaluation of the environment which is better and more meaningful to visit.Therefore,a landscape must have a good environment.Landscape exists in nature as well as in cities.Every corner of a city can be a landscape.Its connection with the city and the citizens is inseparable.However,due to the acceleration of urbanization,there are still many problems in the urban environment.To solve these problems perfectly,we should work from the aesthetic value and planning orientation of the landscape.Therefore,this paper discusses and analyzes the problems of urban environment and how to use the aesthetic value and orientation to construct urban environmental landscape.

Research Characteristics of Thermal Comfort of Urban Block Landscape Based on Knowledge Graph Analysis

The landscape environment of urban blocks plays a significant role in improving the comfort of urban thermal environment and promoting green and high-quality development.The 342 papers related to the research on the impact of urban block landscape environment on thermal comfort in China,collected by CNKI(China National Knowledge Infrastructure)from 2002 to 2022,are used as the research object.Through bibliometric statistical analysis,LLR algorithm,and cluster analysis,the current research status of the impact of urban block landscape environment on thermal comfort in China is analyzed and processed,and its external characteristics are identified.Using the information visualization software CiteSpace,the research topics in the field of the impact of urban block landscape environment on thermal comfort are presented in the form of knowledge graphs.Through co-occurrence analysis of keywords and trend of word frequency changes,the development trends of research hotspots and cutting-edge fields of the impact of urban block landscape environment on thermal comfort are determined,hoping to provide reference for future research in this field.

Implications of Dynamic Interactions between Meteorological Patterns and Surface Water Quality on Environmental Health—A Case Study of the Nairobi River

Urban areas face significant challenges in maintaining water quality amidst increasing urbanization and changing climatic patterns. This study investigates the complex interplay between meteorological variables and water quality parameters in Nairobi City, focusing on the impacts of rainfall and temperature on surface water quality. Data from multiple sources, including the Water Resources Authority, Nairobi Water and Sewerage Company, and the World Bank’s Climate Change Knowledge Portal, were analyzed to assess the relationships between meteorological variables (rainfall and temperature) and water quality parameters (such as electroconductivity, biochemical oxygen demand, chloride, and pH). The analysis reveals varying impacts of rainfall and temperature on different water quality parameters. While parameters like iron and pH show strong relationships with both rainfall and temperature, others such as ammonia and nitrate exhibit moderate relationships. Additionally, the study highlights the influence of runoff, urbanization, and industrial activities on water quality, emphasizing the need for holistic management approaches. Recommendations encompass the establishment of annual publications on Nairobi River water quality, online accessibility of water quality data, development of hydrological models, spatial analysis, and fostering cross-disciplinary research collaborations. Implementing these recommendations can enhance water quality management practices, mitigate risks, and safeguard environmental integrity in Nairobi City.

Open-Air Quarries in the Urban Commune of Zinder (South-East Niger): An Opportunity with Strong Externalities

The framing of this theme would contribute to a better analysis of the benefits of open-air quarrying in Zinder, and should make it possible to understand and measure the socio-environmental externalities of this type of activity in an urban environment. The approach method consisted of carrying out surveys combined with field observations and interviews with the various stakeholders as well as the local population. The results obtained made it possible to identify both positive and negative impacts. The positive impacts are above all the advantages derived from these aggregate quarries, in particular, the creation of direct and permanent jobs and the increase in community income. The price of piling up a truck costs around 28,000 CFA ($56 CAN) and that of loading is around 10,000 F CFA ($20 CAN). This has the effect of removing young people (20 - 39 years old) from the circuit of migration outside the region and even the country. The possibility of using the extraction sites by the local population was identified, in terms of profits relating to fish farming, off-season crops, animal drinking and reclaimed plots. The study also noted negative externalities, such as the temptation of young boys to become involved in extractive activities for immediate gains at the expense of school attendance. Added to this is the upheaval in the topography of the urban landscape, pollution and nuisances (noise, visual and olfactory), while the disappearance or clogging of quarry ponds is the cause of frequent flooding in the neighborhoods. In short, corrective measures (e.g. the revegetation of sites) certainly make it possible to minimize the harmful impacts on the urban environment. But, to improve the performance and organizational capacity of the quarrying industry in Niger, even stronger regulation, training and awareness of stakeholders prove to be the necessary measures.

Characteristics and Trends of Urban Waterfront Human Settlements Based on CiteSpace

Urban waterfront human settlements have gradually become a hot topic for research in recent years.Using CiteSpace,597 publications from 2017 to 2023 that were retrieved from the Web of Science were analyzed and sorted out,and the following characteristics were found:(1)The research hotspots transitioned from thermal comfort evaluation to the functional mechanism of water bodies,and then to the impact on the environment and residents’behavior.(2)The integration of disciplines has promoted the diversification of perspectives on urban waterfront human settlements,and the content has become more concentrated in interdisciplinary fields.Research on corresponding technology and methods of urban waterfront human settlement has improved,and so has the extensiveness of the experiments.(3)The research on urban waterfront human settlement from the perspective of ecology has been improving.The research focuses more on the harmonious coexistence of ecological and cultural values and human beings.

Construction of Urban Overall Water Environment in Xi'an City

[Objective] The aim was to study on construction of overall water environment in Xi＇an. [Method] The study discussed necessity and basic principles of over-all restoration and construction of ＂Chang＇an Eight Water＂ from urban planning, and explored related methods from long term planning and concrete construction approaches. [Result] The study proposed that urban landscape substrates of ＂Chang＇ an Eight Water＂ should be restored based on overall planning about urban water environment, change of linear metabolism, and construction of drainage circulation system. Furthermore, self-circulation and purification of rainfall and sewage could be made use of there in view of present urban water environment. In addition, urban ＂metabolism＂ should be restored progressively to improve urban environment with consideration of water catchment, storage, and diversion. [Conclusion] We should take the initiative to catch the special opportunity to build Xi＇an into an international metropolis with overall planning, designing and implementation, which will be conducive to reconstruction of water system and pleasant surroundings, and to presentation of urban ecosystem and context in ＂Chang＇an Eight Water＂, providing many opportunities for urban development.

Impacts of Urban Expansion on the Urban Thermal Environment:A Case Study of Changchun,China

Urbanization,especially urban land expansion,has a profound influence on the urban thermal environment.Cities in Northeast China face remarkably uneven development and environmental issues,and thus it is necessary to strengthen the diagnosis of thermal environmental pressure brought by urbanization.In this study,multi remote sensing imageries and statistical approaches,involving piecewise linear regression(PLR),were used to explore urban expansion and its effects on the thermal environment of Changchun City in Jilin Province,China.Results show that Changchun experienced rapid urban expansion from 2000 to 2020,with urban built-up areas increasing from 171.77 to 525.14 km^(2).The area of the city’s urban heat island(UHI)increased dramatically,during both day and night.Using PLR,a positive linear correlation of built-up density with land surface temperature(LST)was detected,with critical breakpoints of 70%-80%during the daytime and 40%-50%at nighttime.Above the thresholds,the magnitude of LST in response to built-up density significantly increased with intensifying urbanization,especially for nighttime LST.An analysis of the relative frequency distributions(RFDs)of LST reveals that rapid urbanization resulted in a significant increase of mean LST in newly urbanized areas,but had weak effects on daytime LST change in existing urban area.Urban expansion also contributed to a constant decrease of spatial heterogeneity of LST in existing urban area,especially at daytime.However,in newly urbanized areas,the spatial heterogeneity of LST was decreased during the daytime but increased at nighttime due to urbanization.

Novel algorithm for detection and identification of radioactive materials in an urban environment

This study introduces a novel algorithm to detect and identify radioactive materials in urban settings using time-series detector response data. To address the challenges posed by varying backgrounds and to enhance the quality and reliability of the energy spectrum data, we devised a temporal energy window. This partitioned the time-series detector response data, resulting in energy spectra that emphasize the vital information pertaining to radioactive materials. We then extracted characteristic features of these energy spectra, relying on the formation mechanism and measurement principles of the gammaray instrument spectrum. These features encompassed aggregated counts, peak-to-flat ratios, and peak-to-peak ratios. This methodology not only simplified the interpretation of the energy spectra's physical significance but also eliminated the necessity for peak searching and individual peak analyses. Given the requirements of imbalanced multi-classification, we created a detection and identification model using a weighted k-nearest neighbors(KNN) framework. This model recognized that energy spectra of identical radioactive materials exhibit minimal inter-class similarity. Consequently, it considerably boosted the classification accuracy of minority classes, enhancing the classifier's overall efficacy. We also executed a series of comparative experiments. Established methods for radionuclide identification classification, such as standard KNN, support vector machine, Bayesian network, and random tree, were used for comparison purposes. Our proposed algorithm realized an F1 measure of 0.9868 on the time-series detector response data, reflecting a minimum enhancement of 0.3% in comparison with other techniques. The results conclusively show that our algorithm outperforms others when applied to time-series detector response data in urban contexts.

The impacts of urbanization on soil erosion in the Loess Plateau region

The accelerated urbanization has resulted in new soil erosion in the Loess Plateau region since the 1980s. A concept of urban erosion and its impacts on environment are discussed. The experimental studies and field investigations show that those loose silt and earth piles formed by urban construction can be eroded seriously: Under stormy rain, the amount of sediment from steep man-dumped slope is 10.8–12.2 times that of from uncovered slope land; the result of experiments with the wind tunnel also shows that the damage to the surface structure of dry loess can cause serious soil erosion by wind in some cities of the region. Even if in the urban built-up area, there are many loose sandy soil, mud and silt, which are washed into rivers by city’s ground flow in the rainy season. So, anthropogenically induced soil erosion has made soil erosion more serious around the urban areas. And the urban eroded environment has several characteristics such as fragility, complexity, seasonality and quick variability. Urban areas witness a quick economic growth and have more construction projects than rural areas, which brings more intensive changes of environments during a short period of time or adds some new elements to the erosion system. Therefore erosion has experienced more intensive impact by human activities. So, the possible impact of urbanization on erosion environment must be taken into consideration when designing or planning to exploit natural resources or to develop urban areas in the Loess Plateau.

Planning and Ecological Landscape Design of Urban Constructed Wetland

In addition to purifying water, constructed wetland has become an important ecological landscape in city. The characteristics and key design points of constructed wetland under the ecological principles were explored, taking the Jingyue Lake in Zhongxiang City, Hubei Province for example, treatment processes were designed for different infl ow waters on the basis of site analysis to facilitate the water environment control and ecological landscape construction, ecological theories were applied to explore functional layouts and landscape designs of wetland, to build a favorable ecological environment of urban wetland and design outstanding wetland ecological landscapes.