Implications of recent changes in urban population structure for local goods and services

Journal of Housing and the Built Environment -     

Analyzing growth and mortality in a subtropical urban forest ecosystem

Information on urban tree growth, mortality and in-growth is currently being used to estimate urban forest structure changes and ecosystem services such as carbon sequestration. This study reports on tree diameter growth and mortality in 65 plots distributed among four land use categories, which were established in 2005/2006 in Gainesville, Florida, USA and were re-measured in 2009. Models for mortality and in-growth models were developed by grouping species into hardwoods and softwoods. Annual change in tree diameter at breast height growth was analyzed using three tree species groups based on potential height and longevity. Additionally, the four most common tree species in the study area were modeled to explore factors affecting tree growth. The average annual mortality rate in the city was 9.97%. Trees located in Institutional land use/land cover (LULC) had the highest annual mortality rate (19.2%/yr), and commercial had the lowest (3.1%/yr). Overall, growth rates for the study area (0.70 cm/yr) and residential LULC (0.80 cm/yr) were comparable to other studies. Growth rates for trees in forested areas were higher (0.56 cm/yr) than those previously reported. Individual species-level growth rates such as those for Juniperus virginiana (1.24 cm/yr) and Quercus virginiana (1.08 cm/yr) were different than other species values reported in other studies. Maintenance activities, site conditions, soil properties, tree characteristics, and LULC significantly influenced urban tree growth, mortality, and in-growth. Results can be used to better understand urban forest ecosystem structure and services in medium sized, subtropical cities and to make better decisions regarding planting and maintenance strategies.     

Prioritizing urban rivers' ecosystem services: An importance-performance analysis

The importance-performance analysis (IPA) has been developed and widely utilized to understand customer satisfaction and prioritize provision strategies based on the assumption that satisfaction is resultant from a preference (perceived importance) for a service and a relevant judgment of its performance. However, little work has been performed to examine to what degree different social groups are satisfied with diverse ecosystem services provided by urban rivers, being a unique yet underinvested public good. This study pioneers the IPA application to systematically analyze local communities' perceived importance of urban rivers' ecosystem services and their perceptions about how well those ecosystem services have been provided by urban rivers in Guangzhou (south China). We found notable importance-performance gaps for 10 out of 12 ecosystem services. The local residents were more dissatisfied with provision performance than the non-locals even though both groups of residents could explicitly recognize the importance of urban rivers' ecosystem services. Enhancement of water purification was ranked first amongst all ecosystem services by all respondents, irrespective of respondents' hukou status (Chinese household registration system) and residing environment. Thus, this ecosystem service should be prioritized in relevant management and restoration initiatives. These data provide an accurate picture of potential approaches for the improvement and prioritization of ecosystem services that would satisfy the respective target groups' needs. The IPA offers a mechanism to help match local residents' needs with ecosystem services provision. The IPA also has promise as a means of helping decision-makers and practitioners to communicate effectively with various social groups holding diverging expectations and levels of satisfaction. Such communication is essential to curate urban spaces enjoyed and appreciated by diverse social groups via inclusive urban ecosystem governance.     

A framework for the future of urban underground engineering

A special and holistic approach is needed that captures aggregate attributes and emergent behaviors of the complex system of infrastructure systems in a region. Effective management of the impacts of future population growth, urbanization, and risks arising from continued evolution of our natural, physical and human/societal systems will require a systematic exploration and characterization of the urban subsurface, including much improved understanding and assessment of geologic risks. With recent cost escalations for underground construction projects, incentives are needed for the underground construction industry to develop and implement innovations in methods and technology, and smart integrated planning is needed to reduce costs both during construction and with life-cycle engineered design and operation of our subsurface facilities.The needed framework requires investigation of potential metrics that reflect the performance of aggregate functions of an urban environment so that we can holistically study system performance response under “normal” and “stressed” operation. Such a metric can support a cross-disciplinary exploration of urban resilience, and build knowledge as we develop and test theory and models that explore resilience of complex socio-technical systems. Econometrics with spatial and temporal granularity will help to understand the integrated functionality of our cities and to establish appropriate policies that will drive continuous improvement in the quality of urban life while providing natural, human, and physical urban environmental resilience. The underground in urban regions can become an important component of managing the increasing complexity of our physical systems, and can also make more significant contributions to improving the robustness and resilience of our future cities.     

Developing a land-cover classification to select indicators of forest ecosystem health in a rapidly urbanizing landscape

As moderate-sized cities become more urbanized, ecosystems are altered by land-use change. Key ecological services, such as clean air and water, drought and flood protection, soil generation and preservation, and detoxification of wastes are disrupted, risking the health and welfare of society. An understanding of ecosystem responses to urbanization is necessary to evaluate and balance short-term needs with long-term sustainability goals. Our main objective was to develop a land management and planning tool using a land-cover classification to select landscape indicators of ecosystem health near Columbus, GA. Spearman's Rho correlations were calculated to compare landscape and field-based indicators. Results suggest there are significant inverse correlations between ‘percent forest land-cover’ and ‘population, housing, and road densities’; ‘tree species richness’ and ‘forest patch density’; ‘percent urban land-cover’ and ‘lichen species richness’; ‘lichen incidence’ and ‘forest perimeter-area fractal dimension’. Overall, there were 152 significant urban/biological correlations obtained from this assessment (Rho ≥ |0.50| and p ≤ 0.10). Such a tool could prove useful to land managers and environmental planners by providing a quick and simple method to assess broad areas of land in a single analysis.     

Contextual variations in perceived social values of ecosystem services of urban parks: A comparative study of China and Australia

Parks are an integral part of urban environment which provide a range of ecosystem services. While a great deal of efforts has been invested to investigate monetary and biophysical benefits of natural ecosystems, very few studies have explored socio-ecological values of urban parks. Comparative studies of ecosystem services from urban parks between multiple countries are even rarer. To address this research gap, we have compared users' perceptions of ecosystem services of two major urban parks in China (Dufu Cottage, Chengdu) and in Australia (Kings Park, Perth). Using an ecosystem services framework, we explored three key questions: (i) which ecosystem services are perceived to be most important? (ii) what are the trends of ecosystem services provided by the park? and (iii) which demographic and socio-economic factors influence users' perceptions most? We observed that there is no substantial difference in users' perceptions (in terms of importance and trend) of ecosystem services between two countries, except for microclimate service. Respondents in Dufu Cottage perceived microclimate as the most important service while in Kings Park, a number of services (e.g., aesthetic, habitat and recreational) received almost equal importance. Almost two-thirds of the respondents have perceived an increased level ecosystem services over the last five years. Various socio-demographic factors, such as gender, age, income level and frequency of visits influenced users' perceptions most significantly. These results have critical implications in designing more environmentally sensitive as well as user-oriented urban parks.     

Role of museums and botanical gardens in ecosystem services in developing countries: case study and outlook

Unprecedented environmental challenges require new tools. Knowledge based on scientific research is critical for the creation of environmental awareness and education in order to bring about behavioural changes in society at large. Well-structured museums and botanical gardens in developing countries can play significant roles in research, education, and conservation even when governmental institutions are weak and underfunded. The paper offers a case study of the nascent Palestine Institute of Sustainability and Palestine Museum of Natural History with a botanical garden. The related SWOT (strengths, weaknesses, opportunities, and threats) analysis concludes that, despite some limitations and challenges, this is a successful model that should be replicated in other impoverished communities.     

City size,prices, and efficiency for individual goods and services

Studies indicate that the cost of living either is the same or rises slightly with the size of cities. This suggests — though it does not imply — that prices of goods and services are as high or higher in larger cities than in smaller cities. But is this really so? And if so, does this imply that costs of distribution (and of the production of services) are higher in bigger cities? The relationship of prices to the sizes of cities is examined for 193 individual goods and services and for 23 broad groups. Price alone does not indicate efficiency. It is well-established that wages for the same work at given skill levels are higher in larger cities. Therefore, the total real inputs may be lower in a larger city, even if price is higher, which indicates better efficiency in larger cities. Study of individual goods and services, and of groupings of them, enables us to go beyond prices to learn which categories are offered more efficiently and which less efficiently in larger cities. We find that for most goods, economic cost decreases rather than increases with city size.     

城市节能的关键性能指标

根据中国城市能耗特点,提出将城市能耗分为生产性能耗和消费性能耗两大类型。指出生产性能耗主要用效率指标来评价;消费性能耗应尽量用实物量指标来评价,也就是用量化的强度性指标EUI(energy use intensity)评价,实现评价指标的可测量、可核查、可报告。即使采用相对性指标(如百分比指标),也一定要有明确的基准线。提出了城市生产性能耗、消费性能耗以及城市能源系统的关键性能指标。     

城市森林公园消防规划设计

针对城市森林公园具有森林、建筑火灾的双重特点,按照消防设计的一般惯例和可借鉴的规范,并结合城市森林公园的实际情况,阐述了城市森林公园消肪规划设计应具备的项目和具体内容。     

城市化生态与城市可持续发展

论述了城市化进程对城市生态环境带来的影响,介绍了城市生态系统的主要特点及存在的问题,并提出了以生态学为基础的城市可持续发展观,从而建立一个社会生态系统、经济生态系统和自然生态系统协调发展的可持续发展城市。     

Lake ecosystem health assessment: indicators and methods

A set of ecological indicators including structural, functional, and system-level aspects were proposed for a lake ecosystem health assessment, according to the structural, functional, and system-level responses of lake ecosystems to chemical stresses including acidification, eutrophication and copper, oil and pesticide contamination. The structural indicators included phytoplankton cell size and biomass, zooplankton body size and biomass, species diversity, macro- and micro-zooplankton biomass, the zooplankton phytoplankton ratio, and the macrozooplankton microzooplankton ratio. The functional indicators encompassed the algal C assimilation ratio, resource use efficiency, community production, gross production/respiration (i.e. P/R) ratio, gross production standing crop biomass (i.e. P/B) ratio, and standing crop biomass unit energy flow (i.e. B/E) ratio. The ecosystem-level indicators conisisted of ecological buffer capacities, energy, and structural energy. Based on these indicators, a direct measurement method (DMM) and an ecological modeling method (EMM) for lake ecosystem health assessment were developed. The DMM procedures were designed to: (1) identify key indicators; (2) measure directly or calculate indirectly the selected indicators; and, (3) assess ecosystem health on the basis of the indicator values. The EMM procedures were designed to: (1) determine the structure and complexity of the ecological model according to the lake's ecosystem structure; (2) establish an ecological model by designing a conceptual diagram, establishing model equations, and estimating model pararmeters; (3) compare the simulated values of important state variables and process rates with actual observations; (4) calculate ecosystem health indicators using the ecological model; and, (5) assess lake ecosystem health according to the values of the ecological indicators. The results of a case study demonstrated that both methods provided similar results which corresponded with the lake's actual trophic state.     

Assessing and mapping ecosystem services to support urban green infrastructure: The case of Barcelona,Spain

The ecosystem services approach provides an efficient way to support urban green infrastructure planning. Such an assessment, together with mapping, can effectively produce spatial analyses on a specific scale, helping to maintain multi-functional landscapes and plan urban green infrastructure. In turn, green infrastructure can offer a wide variety of ecosystem services, promoting landscape sustainability. This study develops a methodology for the planning of urban green infrastructure based on an ecosystem services approach that assesses the supply capacity of ecosystem services, and identifies possible spatial characteristic areas for interlinking urban green infrastructure within the study area. More specifically, from a landscape perspective, we use 32 ecosystem services (as X-axis) and different land use types (as Y-axis) to build an ecosystem service assessment matrix. We then take the municipality of Barcelona as an example, using the latter to assess and map ecosystem services within the city through ArcGIS, which shows the spatial distribution characteristics of ecosystem services provision. We identify possible spatial areas - which include ecosystem services provision, barren, and obstructed areas - by overlapping the ecosystem services assessment maps. Ultimately, the results provide a reference for urban green infrastructure planning by recognizing priority protected areas, new construction areas, potential areas, and renewal areas.     

Socio-economic and spatial indicators for household energy for a tropical urban community in urban Manila

Partly based on a household energy survey, this paper highlights the need to understand the complexities of the increasing urban growth rate around the world. The community, Baranggay 557 in the city of Manila is described, including structure and energy patterns, thus leading to an approach towards indicators and the rudiments of an energy policy. Cette etude, qui se fonde en partie sur une enquete relative a la consommation domestique d'energie, met en lumiere la necessite de mieux comprendre la complexite engondree par le taux rapide de croissance urbaine dans le monde. On y trouve une analyse de la collectivite en question - Baranggay 557 a Manille - qui en expose la structure et les modes de consommation d'energie. Les donnees ainsi recueillies font apparaitre des indicateurs, ainsi qu'une premiere ebauche de politique en matiere d'energie.     

Towards sustainable urban water services in developing countries: tariffs based on willingness-to-pay studies

ABSTRACT

Water supply and sanitation (WASH) service providers in most towns of developing countries, such as Godey Town in Ethiopia, the case study reported in this paper, deliver less than basic services. The costs for meeting the more ambitious WASH targets of the Sustainable Development Goals will be much higher than what has previously been invested in the sector. This study showed that a tariff structure designed using affordability and willingness-to-pay data would provide higher revenues than one solely based on estimated customers’ affordability, or Ethiopian government’s tariff guidelines. As in previous studies in Ethiopia, this study highlights government’s low willingness-to-charge amidst a high customers’ willingness-to-pay. Yet, there is need to increase water tariffs in developing countries, hence, moving towards financial sustainability and supplementing the other two Ts – taxes and transfers. Based on accurate and updated socio-economic data, the tariff can also be optimised to fulfil the social equity objective.     

Assessing biological indicators for remediated anthropogenic urban soils

Anthropogenic urban soils, including brownfield soils, are currently characterised and evaluated using mainly physico-chemical properties. Our objective was to determine if biological indicators could provide a more comprehensive soil quality assessment relative to sustainability, identifying contamination issues, and effectiveness of remediation strategies. Plant, invertebrate and microbial assays and functional processes were evaluated at 10 brownfield/anthropogenic urban locations at different stages of remediation in northwest England. Extreme sites were discriminated on the basis of earthworm counts and a small number of indicators likely to be related to their activity. It was concluded that identifying a universally-applicable benchmark suite of biological indicators is very unlikely without considerable advancement of knowledge and technology.     

A framework to analyse inclusiveness of urban policy

From 2007 onwards, Indian policy planning follows the broad vision of achieving inclusive growth. All sectors of national development align their policy objectives towards this overall vision. Urban policy is one such crucial policy sector oversees by the Ministry of urban development. This paper analyses the urban policy and investigates its impact in achieving inclusive urban growth in India. The traditional methodology of analysing urban policy by utility or output has its own limitations. It only considers summary variables of policy (utility or benefits) but not the situational variation on ground. Further, it cannot quantify the precise time of the change in opportunities or ability occurred over time. So it cannot inform the moment when a policy achieves its objectives. The research employs human capability instead of utility to overcome the present limitations. The analysis methodology is adapted from Professor Amartya Sen's capability approach. Capability approach emphasises a shift in policy analysis from direct assistance to expansion of opportunities and eliminate circumstantial imperfection in governance. The approach aims towards empowering urban citizen, and advancement towards the direction of more self-reliance society.     

A planning-oriented sustainability assessment framework for peri-urban water management in developing countries

DPSIR and the three-pillar model are well-established frameworks for sustainability assessment. This paper proposes a planning-oriented sustainability assessment framework (POSAF). It is informed by those frameworks but differs insofar as it puts more emphasis on a constructivist conception which recognises that sustainability needs to be defined anew for each planning problem. In finding such a consensus definition, POSAF uses participatory scenario analysis and participatory planning, technical feasibility study, participatory assessment, analysis of trade-offs and social networks in an unusual combination and for goals that differ from the original conceptions of these methods. POSAF was applied in a peri-urban area of Mexico City for the design of improved water service provision, integrating solid waste management. It supported consensus amongst users about the importance of environmental issues, informed planners about the values of stakeholders and users, detected local differences, and identified possible conflicts at an early stage of decision-making.     

Sustainable smart city development framework for developing countries

ABSTRACT

Basic requirements of sustainable smart cities in a developing country are the entitlement of facilities. Here, an index named Smart Sustainable City Development Index (SSCDI) has been developed for three Indian Smart Cities. A hierarchical method has been used to construct the index with multiple layers of indicators capturing characteristics of the dimensions such as social, economic, environment, culture and lifestyle. This index is used to assess performances of the three case study cities based on the scores in various indicators. This SSCDI framework provides a conceptual landscape for developing countries for planning their sustainable urban development and evaluation of performances.