Modelling of Nature-Based Solutions (NBS) for Urban Water Management—Investment and Outscaling Implications at Basin and Regional Levels

This manuscript is an attempt to demonstrate effectiveness of nature-based solutions (NBS) and measures to reduce risk of flooding and environmental impact in urban settings. The nature-based solutions (NBS) were assessed as scenarios from experience of urban storm drainage and sewerage systems based on practices that improve urban water management through modelling using urban stormwater management model (SWMM). The model has been applied in a typical urban environment in the second city in Botswana, the City of Francistown, which has a population of more than one hundred thousand. By considering the 2-yr and 10-year storm events in a calibrated SWMM, NBS scenarios from a mix of low impact and drainage measures were considered. The considered NBS scenarios were used to determine their effectiveness in terms of reducing and controlling peak runoff, flood volumes, infiltration and evapotranspiration in the study area, which are vital in assessing the opportunity and challenge for sustainable management of water resources and associated tradeoff of investments in the urban contexts. The study demonstrates the usefulness of implementing effective measures for achieving NBS in urban context and possibility of outscaling at basin and regional levels.

DEVELOPMENT OF THE ENERGY MANAGEMENT STRATEGY FOR PARALLEL HYBRID ELECTRIC URBAN BUSES

A novel parallel hybrid electrical urban bus （PHEUB） configuration consisting of an extra one-way clutch and an automatic mechanical transmission （AMT） is taken as the study subject. An energy management strategy combining a logic threshold approach and an instantaneous optimization algorithm is proposed for the investigated PHEUB. The objective of the energy management strategy is to achieve acceptable vehicle performance and drivability requirements while simultaneously maximizing the engine fuel consumption and maintaining the battery state of charge in its operation range at all times. Under the environment of Matlab/Simulink, a computer simulation model for the PHEUB is constructed by using the model building method combining theoretical analysis and bench test data. Simulation and experiment results for China Typical Bus Driving Schedule at Urban District （CTBDS_UD） are obtained, and the results indicate that the proposed control strategy not only controls the hybrid system efficiently but also improves the fuel economy significantly.

On the Use of Agent Based Modelling for Addressing the Social Component of Urban Water Management in Europe

The paper aimed to provide a review of different tools that estimate how human behavior changes by water management strategies and quantify this change to support the decisions of urban water managers. To support decision makers, it is essential to be able to model the urban water system’s human part explicitly and link it to the hydro system’s response, rather than only explore the reaction of the system based on scenarios. To do so, tools are needed that can model the human part of the system, explore its reaction to potential changes and dynamically link back this to the techno-environmental model of the water system. This work reviews state-of-the-art ABMs that are publicly available focusing on the human part of the urban water system in Europe. The review leads to the proposals of three pillars for future development of ABMs for urban water management in Europe: end-user enablement;Machine Learning and Artificial Intelligence integration and adversaries modelling.

Insights from i-Tree Eco-efficiency Assessment Management of Urban Trees in Oxford,UK

In the era of stock development following the acceleration of urbanization,the revitalization of urban green space has assumed an increasingly significant role.Consequently,the management of urban trees has emerged as a critical focus of urban governance,contributing to the enhancement of livability in human settlements.This study offers a comprehensive analysis of the urban tree management system in Oxford,UK,identifying that its primary objective is to optimize and maintain a harmonious balance between human activities and the natural environment through the implementation of high-quality planting practices.The system emphasizes enhanced management practices and establishes a robust framework for the development of targeted policies and management regulations,utilizing i-Tree eco-efficiency assessment and real-time feedback mechanisms.China’s urban tree management is in its nascent stages,and there is an urgent need for the development of urban green space.By adopting the refined management assessment methodologies employed for urban trees in Oxford,UK,it is possible to enhance the ecological value of urban trees,which represent a significant green resource within cities,and contribute to the creation of more livable urban spaces.

Future urban transport management

The incorporation of disruptive innovations into the transportation industry will inevitably cause major upheavals in the transportation sector.However,existing research lacks systematic theories and methodologies to represent the underlying characteristics of future urban transport systems.Furthermore,emerging modes in urban mobility have not been sufficiently studied.The National Natural Science Foundation of China(NSFC)officially approved the Basic Science Center project titled“Future Urban Transport Management”in 2022.The project members include leading scientists and engineers from Beijing Jiaotong University,Beihang University,and Beijing Transport Institute.Based on a wide range of previous projects by the consortium on urban mobility and sustainable cities,this project will encompass transdisciplinary and interdisciplinary research to explore critical issues affecting future urban traffic management.It aims to develop fundamental theories and methods based on social and technological developments in the near future and explores innovative solutions to implement alongside these emerging developments in urban mobility.

基于VB6．0的克拉玛依中心城区园林绿地管护信息系统开发与应用

根据克拉玛依的气候、土壤、水资源等环境条件,以VB6.0为开发工具,结合Mapinfo及其组件MapX连接Access数据库开发克拉玛依中心城区园林绿地管护信息系统,实现了园林绿地信息的GIS管理和管护信息技术和基本资料的动态查询。

Rooftop Rainwater Harvesting as an Alternative Domestic Water Resource in Zambia

Within the last decade, substantial progress has been achieved in the management of centralized water reticulation in Zambia. Characterized by diversified fiscal resourcing, concurrent institutional restructuring and introduction of new players in water governance, the water sector is set to achieve improved reliability on sustainable grounds. However, the threat of underground water pollution resulting from increased urbanization besides the unreliable energy sector presents new challenges for the current urban water. In effect, urban areas are affected by chronic water rationing creating public stress and insecurity which impacts domestic development. While the course of development has meant investment in the extension and expansion of water infrastructure in Zambia, alternative urban water resources are being sought to address challenges of traditional water systems globally. This paper therefore attempts to make a case for the modernization of Rooftop Rainwater Harvesting (RRWH) as an augmenting water resource in the Zambian urban housing sector. Here—in, it is identified as a Low Impact Development technology within the Integrated Urban Water Management framework currently being forged by local water. Based on a desktop literature survey and online questionnaire survey, an argument to support the development of RRWH in Zambia was developed. While literature survey results revealed evidence of economic loss and a growing compromise to public health resulting from inconsistent water supply in the study area of Lusaka city, the online questionnaire survey depicted significant domestic stress due to erratic water supply. Results confirmed that at one time residents observed an average of eight hours of power blackouts which effectively induced water disruption forcing homeowners to engage in various water storage methods which in turn are costly on domestic time, health and finances. A retrospective discussion based on both survey results attempts to present benefits and opportunities of urban RRWH to water sector stakeholders providing recommendations towards the mainstreaming of the practice in Zambia.

China Urban Land Management:Options for an Emerging Market Economy

This paper is the Executive Summary of a WorldBank Report with the subject of“China Urban Land Man-agement:Options for an Emerging Market Economy”,which was presented by a preparation mission headed byMr.Andrew Hamer,Principal Economist of the WorldBank,By the Permission of Mr.Hamer,we hereby pub-lish this paper in our journal.

Operation and Maintenance Challenges in China“Sponge City”Program

China started a Sponge City program to offset the adverse impacts of urban developments and to tackle many water-related problems.By emphasizing stormwater management practices with“natural solutions”,many positive results have been achieved.The operation and maintenance(O&M)of Sponge City to support long-term success gained considerable focus.China is facing challenges many developed countries have encountered,as well as unique ones due to specific social,economic,and environmental conditions.This study identified and discussed Sponge City O&M challenges:(1)scheduling challenges,(2)technical challenges,(3)in short of local regulation/ordnance,(4)inadequate O&M assessment standard,(5)underprovided training,(6)PPP related concerns,(7)inter-agency coordination needs,(8)ownership and responsible party issues,(9)substandard documentation,and(10)funding and financial concerns.Selected cases and progress in pilot cities are introduced in the discussions.

An Integrated Remote Sensing and GIS in Monitoring Landuse and Land Cover Change in Egbeda Local Government Area, Oyo State, Nigeria

Effective planning relies on accurate and up-to-date information on existing land use and land cover. The timely detection of trends in land use and land cover change and a quantification of such trends are of specific interest to planners and decision makers. The aim of this research is to use remote sensing and GIS to monitor landuse and land cover change in Egbeda Local Government Area, Oyo State with a view to determining how useful such information can be to planners and decision makers for effective urban management. The research was conducted using remote sensing and Geographical information System at determining the trend and extent of land use and land cover change and its driving force in Egbeda Local Government Area, Oyo State. The methods used include: digitization, digital image processing and spatial analysis using an inverse distance weighted (IDW) technique, Maximum likelihood supervised classification and post classification change detection techniques were applied to Landsat imageries acquired in 1984, 2006 and 2018. Imageries were classified into built-up area, vegetation, bare surface, cultivation and water body. The results of the analysis obtained showed drastic change in built-up area which rose to 32.8% from 25.4% between 1984 and 2018 periods. To reduce the effect of land use expansion in the study areas, policy measures were recommended which include proper inventory of land use and land cover, regular monitoring of urban areas spread of development and regional development programs. These will enable the government, stakeholders, policy makers and planners to make informed decisions provided by these technologies to attain and sustain future urban development.

Developing an integrated urban ecological efficiency framework for spatial ecological planning:A case on a tropical mega metropolitan area of the global south

Rapid urbanization has emerged as one of the most critical challenges to ecological sustainability in urban areas.In developing countries,the degradation of the ecosystem is more prominent due to the lack of urban planning.Thus,it has become urgent for researchers to identify the ecological efficiency(EE)changes imposed by urban expansion and promote sustainable land use planning.This study aims to develop a comprehensive urban ecological efficiency(UEE)framework in the Kolkata Metropolitan Area(KMA),India,from 2000 to 2020.Principal component analysis(PCA)was used to develop a remote sensing-based UEE index(UEEI)based on five effective ecological parameters(Greenness,Dryness,Heat,Wetness and vegetation health.A single sensitivity parameter was also calculated to determine the role of a single parameter based on which management strategies can be carried out.The findings showed that(i)there were substantial deteriorations of UEE in the last 20 years.In 2000 the areas with good EE were about 65.5%which declined to 53.72%in 2010 and 20.87%in 2020.The areas with good UEE decreased 68%and 61%from 2000 to 2020 and 2010 to 2020,respectively;(ii)the areas with good UEE were 52%in 2000,while 38%in 2010.Most urban centres(Bhadreshwar,Champdani,Srirampur,Bally,Howrah,Kamarhati,Baranagar,Dum Dum,South Dum Dum,Rajarhat,Bidhannagar)located around the Kolkata megacity are characterized by poor and very poor EE(ranges of 0.60-1.00).Thus,spatiotemporal pattern of UEE could assist to clarify the administrative responsibilities as well as obligations.In addition to this,the UEE framework can help for scientific guidance of urban ecosystem protection and restoration through comprehensive spatial landscape planning.

The Modern Management of Urban Planning and the Controlling Planning

Since 1980s,with the further reform of political and economic systems,the urban construc-tion in our country has undergone great changes,greater than ever.Such changes pose a series ofnew problems to urban planning:How should planning be suitable for the development of moderncities?How should planning management coordinate with urban planning?How to carry out ur-ban planning under new situations? etc.The answers to these problems lie in one point:urbanplanning and plann ing management must be restructured.Only when the former is well com-bined with the latter can the above problems be solved satisfactorily.This article provides someviews in this respect.

Response of soil macrofauna to urban park reconstruction

This study is based on a park in an industrial city in Ukraine.In 2019,a 2.8 ha area of the park was reconstructed.The park’s reconstruction aimed to create a comfortable environment for visitors and to improve the efficiency of ecosystem services,and thereby enhance the quality of life of citizens.The reconstruction of the park was found to cause changes in the physical properties of soils and the structure of the soil macrofauna community.The increases of soil compaction in the layers at depth 5-20 cm and the soil electrical conductivity were a consequence of technological operations during reconstruction.The park reconstruction activities can also explain 29% of the variation in the soil macrofauna community.Extracting the variation induced by the park reconstruction from the community variation induced by other causes was a major challenge.The specific changes in the community of soil macrofauna following the reconstruction of the park were revealed.The abundance of soil animal species A.rosea,A.trapezoides,H.affinis,H.rufipes,B.affinis was found to increase after the reconstruction.The earthworm A.trapezoides decreased in abundance due to the park reconstruction.

Assessing urban low-carbon performance from a metabolic perspective

How to mitigate anthropogenic carbon emissions in cities determines to a large degree whether global temperature targets in this century are to be met.Using 12 cities in or outside China as case studies,we quantified the critical processes of carbon metabolism based on the urban carbon metabolism assessment framework(CMAF)proposed.The differences of sector contribution,and per capita and intensity among carbon throughflows,carbon inflows and carbon emissions were evaluated.Furthermore,we established an indicator system for CMAF consisting of flow-based and structural indicators to compare the low-carbon performances of cities.The results showed that the total carbon throughflow(TCT)and total carbon inflow(TCI)in Chinese cities were 7–12%higher than in European and American cities regarding the manufacturing and services sector on average,but 6–9%lower in the household consumption sector.Beijing,Tianjin,Nanjing and Guangzhou had lower per capita TCT and TCI than in European and American cities such as Paris and Los Angeles,while their carbon intensities were about three times as much.The per capita TCT in a city was found significantly correlated with per capita energy consumption and had a certain correlation with per capita building or housing area.This study found that TCT,TCI and carbon dioxide emission each provided unique information to measure the potential climatic impact of cities.The difference in the ranking of low-carbon performance between the investigated cities was significant both in terms of flow-based and structural indicators.We suggest these assessment indicators of carbon metabolism be integrated into urban resources management to reflect both the decarbonization status and future emission reduction potential more accurately and to provide systemic decision support for achieving the goal of carbon neutrality in cities.

Integrated water resources management for emergency situations： A case study of Macao

Integrated urban water management （IUWM） is a useful tool that can be used to alleviate water resource shortages in developing regions like Macao, where 98% of the raw water comes from China's Mainland. In Macao, scarce water resources deteriorate rapidly in emergency situations, such as accidental chemical spills upstream of the supply reservoir or salty tides. During these times, only the water from the two freshwater reservoirs in Macao can be used. In this study, we developed urban water management optimization models that integrated the raw water supply from the two reservoirs with various proposed governmental policies （wastewater reuse, rainwater collection, and water saving）. We then determined how various water resource strategies would influence the urban water supply in Macao in emergency situations. Our results showed that, without imported raw water, the water supply from only the two Macao reservoirs would last for 7.95 days. However, when all the government policies were included in the model, the supply could be extended to 13.79 days. Out of the three non-conventional water resources, wastewater reuse is the most beneficial for increasing the Macao water supply, and rainwater collection also has great potential.

Determination of urban runoff coefficient using time series inverse modeling

Runoff coefficient is an important parameter for the decision support of urban stormwater management. However, factors like comprehensive land-use type, variable spatial elevation, dynamic rainfall and groundwater elevation, make the direct estimation of runoff coefficient difficult. This paper presented a novel method to estimate the urban runoff coefficient using the inverse method, where observed time-series catchment outfall flow volume was employed as input for the water balance model and runoff coefficients of different catchments were treated as unknown parameters. A developed constrained minimization objective function was combined to solve the model and minimized error between observed and modeled outfall flow is satisfactory for the presenting of a set of runoff coefficients. Estimated runoff coefficients for the urban catchments in Shanghai downtown area demonstrated that practice of low impact design could play an important role in reducing the urban runoff.

Evaluation of the efficiency of urban solid waste management in Brazil by data envelopment analysis and possible variables of influence

This article has the general objective of estimating the efficiency of urban solid waste management in 940 Brazilian munici-palities through Data Envelopment Analysis(DEA)technique and has specific objectives:(i)to estimate efficiency scores;(ii)to compare the performance between different groups of municipalities;and(ii)to analyze the profile of efficient munici-palities from the perspective of the guidelines of Law 12,305/2010 and socio-economic and environmental indicators.The technique used was DEA with output-oriented and variable scale to return modeling.The results showed higher efficiency scores in the municipalities with populations above 500,000 inhabitants.The score variation ranged from 0.5(municipalities with populations<10,000 inhabitants)to 0.9(municipalities with more than 500,000 inhabitants).Of the sample set,only 12.34%of the municipalities were considered efficient,and when analyzing the efficient group,it was found that adherence to legislation was not a major factor in achieving efficiency.

Evaluation of accuracy of linear regression models in predicting urban stormwater discharge characteristics

Stormwater runoff has been identified as a source of pollution for the environment, especially for receiving waters. In order to quantify and manage the impacts of stormwater runoff on the environment, predictive models and mathematical models have been developed. Predictive tools such as regression models have been widely used to predict stormwater discharge characteristics. Storm event characteristics, such as antecedent dry days （ADD）, have been related to response variables, such as pollutant loads and concentrations. However it has been a controversial issue among many studies to consider ADD as an important variable in predicting stormwater discharge characteristics. In this study, we examined the accuracy of general linear regression models in predicting discharge characteristics of roadway runoff. A total of 17 storm events were monitored in two highway segments, located in Gwangju, Korea. Data from the monitoring were used to calibrate United States Environmental Protection Agency＇s Storm Water Management Model （SWMM）. The calibrated SWMM was simulated for 55 storm events, and the results of total suspended solid （TSS） discharge loads and event mean concentrations （EMC） were extracted. From these data, linear regression models were developed. R2 and p-values of the regression of ADD for both TSS loads and EMCs were investigated. Results showed that pollutant loads were better predicted than pollutant EMC in the multiple regression models. Regression may not provide the true effect of site-specific characteristics, due to uncertainty in the data.

Urban traffic modeling and pattern detection using online map vendors and self-organizing maps

Typical traffic modeling approaches,such as network-based methods and simulation models,have been shown inadequate for urban-scale studies due to the fidelity issue of models.As a go-around,data-driven models have received increasing attention recently.However,most data-driven methods have been restricted by their data source and cannot be scaled up to manage urban-and regional-scale studies.Regarding this issue,this research proposes a pipeline that collects traffic data from online map vendors to bypass data limitations for large-scale studies.The study consists of two experiments:1)recognizing the dominant traffic patterns of cities and 2)site-specific predictions of typical traffic or the most probable locations of patterns of interests.The experiments were conducted on 32 Swiss cities using traffic data that were collected for a two-month period.The results show that dominant patterns can be extracted from the temporal traffic data,and similar patterns exist not only in various parts of a city but also in different cities.Moreover,the results reveal that a country-level lockdown decreased traffic congestions in regional highways but increased those connections near the city centers and the country borders.