Impacts of urban environmental elements on residential housing prices in Guangzhou (China)

The amenity value provided by urban green spaces, water bodies and good environmental quality is difficult to assess and incorporate into urban planning and development. Developers and governments in China hitherto have seldom objectively factored these attributes into property pricing and associated decisions. The hedonic pricing method offers an appropriate approach to gauge such external benefits which contribute to real-estate transaction prices. This study explored the impacts of key environmental elements with a bearing on residential housing value in Guangzhou, including window orientation, green-space view, floor height, proximity to wooded areas and water bodies, and exposure to traffic noise. Four large private housing estates composed of multi-storied blocks with similar design and price bracket, catering to the mass property market, were sampled. Transaction price data and structural attributes of 652 dwelling units were acquired directly from developers. Data on environmental attributes were collected in the field. Two functional hedonic pricing method models, linear and semi-log, were constructed. The semi-log model offered comparatively stronger explanatory power and more reliable estimation. High floor on the multi-storey tenement blocks contributed implicitly 9.2% to the selling price. View of green spaces and proximity to water bodies raised housing price, contributing notably at 7.1% and 13.2%, respectively. Windows with a southern orientation with or without complementary eastern or northern views added 1% to the price. Proximity to nearby wooded area without public access was not significant, expressing the pragmatic mindset in the hedonic behavior. Exposure to traffic noise did not influence willingness-to-pay, implying tolerance of the chronic environmental nuisance in the compact city. The study demonstrates that hedonic pricing method could be applied in the Chinese context with an increasingly expanding and privatized property market. It could inform the decisions of policy makers and property developers concerning land selling and buying, land conversion, property development, urban nature conservation, and design of ecological green-space networks.     

Willingness to pay for reducing fatal risk by improving air quality: a contingent valuation study in Chongqing, China

In China, 76% of all energy comes from coal consumption, which is the major cause of air pollution. One of the major barriers to developing sound policies for controlling air pollution is the lack of information related to the value of the health consequences of air pollution. We conducted a willingness-to-pay (WTP) study using contingent valuation (CV) methods in Chongqing, China to estimate the economic value of saving one statistical life through improving air quality. A sample of 500residents was chosen based on multistage sampling methods. A face-to-face household interview was conducted using a series of hypothetical, open-ended scenarios followed by bidding game questions designed to elicit the respondents' WTP for air pollution reduction. The Two-Part Model was used for estimations. The results show that 96% of respondents were able to express their WTP. Their mean annual income is $490. Their WTP to save one statistical life is $34,458. Marginal increases for saving one statistical life is $240 with 1year age increase, $14,434 with 100yuan monthly income increase, and $1590 with 1year education increase. Unlike developed country, clean air may still be considered as a "luxury" good in China based on the estimation of income elasticity.     

Demand for urban forests in United States cities

Extensive economic investigations have shown a variety of benefits derived from urban forests, but study on demand for urban forests remains limited. This study investigates the impact of selected potential factors on the demand for urban forests at the city level. An empirical economic model is used to examine and estimate the demand for urban forests in all cities with population over 100,000 in the United States. The empirical findings suggest that the demand for urban forests is elastic with respect to price and highly responsive to changes in income. Urban forest area increases as total population grows but at a lower rate than population growth.     

Comprehensive concept planning of urban greening based on ecological principles: a case study in Beijing, China

Greenspace is an important part of complex urban ecosystems and provides significant ecosystem services. It benefits urban communities environmentally, esthetically, recreationally and economically. Beijing Province is in north of China, and has a total area of 16,807.8 km² and a population of about 13.8 million. This paper aims to develop a comprehensive conceptual framework for urban greening of Beijing Province based on landscape ecological principles. It attempts to answer how to establish an urban greening plan at the regional, city and neighborhood levels to achieve long-term sustainability. At the regional level, a big natural and semi-natural forest area in the northwest and an ecological buffer belt in the southeast are planned to protect the environmental quality of Beijing and provide habitats for wildlife. At the city level, a green network system of green wedges, parks and green corridors has been proposed. This green network helps to limit future urban expansion, improve urban environmental quality and serve as habitats and migration routes for wildlife. At the neighborhood level, green extensions and connections of riverside greenway, road greenway, parks and vertical greening permeate into the built-up areas. They provide open space close to residential areas and offer places for recreation. This three-level green system constitutes an integrated ecological network for urban sustainable development of Beijing. For future development of Beijing, urban parks, forestry, agriculture, water and infrastructure should be planned and designed in an integrated way. After this greenspace plan is legislated and completely realized, Beijing will develop an interconnected and integrated network of urban greenspaces. It has the prospect of achieving the aim of “Green Olympic City 2008” and the long-term goal of developing Beijing towards an “Eco-City”.     

Habitat structure influences below ground biocontrol services: A comparison between urban gardens and vacant lots

Urban agriculture offers a framework for local self-reliance by provisioning food security, employment opportunities, and other community benefits. However, urban agriculture must rely on the supporting and regulating services of the soil food web. Hence, we quantified belowground biocontrol activity in urban gardens and vacant lots in two post-industrial cities using an in situ insect baiting technique. Due to the differences in habitat structure, we hypothesized that belowground biocontrol services will differ between gardens and vacant lots and the influence of habitat structure would differ with the type of biocontrol organism. Results revealed that biocontrol activity, as assessed by % mortality of baited insects, varied between 51% and 98% with higher activity often recorded in vacant lots than gardens. Major contributions to bait insect mortality were by ants, followed by microbial pathogens and entomopathogenic nematodes, respectively. Ants showed higher (p < 0.0001) % mortality in vacant lots (60% ± 33.4%) than in urban gardens (33.3% ± 22.2%) whereas microbial pathogens exhibited higher (p < 0.0001) mortality in gardens (27.8% ± 15%) than vacant lots (8.3% ± 16.7%). Ants caused higher (p < 0.0001) mortality when larger-mesh size cages were used compared with the smaller-mesh size cages, but mortality by microbial pathogens did not differ with cage type. The high biocontrol activity indicates the resilience of the soil food web in urban ecosystems and the differential effects of habitat structure on biocontrol activity can help guide landscape planning and vegetation management to enhance urban environments and boost local self-reliance.     

Using economic asset valuation to meet rehabilitation priority needs in the water sector

ABSTRACT

The current study aims at economic asset valuation of water and wastewater infrastructures to prioritize rehabilitation interventions using the infrastructure value index (IVI) as a key performance indicator. The proposed methodology follows a three-step procedure: (1) identification, characterization and site inspection of existing assets; (2) estimation of the current replacement cost and the current value; and (3) establishment of the priority needs. Data from a utility in the Algarve region of Portugal are used as a case study. The specific objectives are to illustrate the methodology and highlight the inherent challenges and complexities associated with economic asset valuation. Results include the IVI calculation for different assets using scenarios of service lives. Different strategic interventions of rehabilitation in the long term were studied, allowing to assess the evolution of IVI, rehabilitation cost and increased risk assets. Asset valuation is important to establish short-term rehabilitation priorities and to analyse long-term strategies of rehabilitation.     

我国现阶段工程量清单计价应用的探讨

阐述了定额计价在工程量清单计价实施初步阶段的影响,从完整性与时效性方面探讨了工程量清单计价应用中主要存在的问题,归纳了解决问题的方法和途径,从而更好地实现对工程造价的有效控制.     

Function-analysis and valuation as a tool to assess land use conflicts in planning for sustainable, multi-functional landscapes

In order to reconcile landscape conservation with changing demands on land use and natural resources, it is essential that the ecological, socio-cultural and economic values of the landscape be fully taken into account in planning and decision-making.This paper presents a comprehensive framework for integrated assessment of ecological services and socio-economic benefits of natural and semi-natural ecosystems and landscapes. The framework can be applied at different scale levels to different ecosystems or landscape-units and basically consists of three steps: (1) Function-analysis: translates ecological complexity into a limited number of ecosystem (or landscape) functions, which, in turn, provide a range of goods and services; (2) Function valuation: includes ecological, socio-cultural and economic valuation methods; and (3) Conflict analysis: to facilitate the application of function-analysis and valuation at different scale levels, it is important to integrate analytical valuation methods with stakeholder participation techniques.The framework presented in this paper facilitates the structured assessment of the (total) value of the goods and services provided by a specific area (landscape) and to analyze the costs and benefits involved in trade-offs between various land use options. The last section of this paper gives some conclusions and recommendations for application-possibilities of function-analysis and valuation to achieve more sustainable landscape use and maintenance of our “natural capital”.     

Housing the urban poor in post-reform China: Some empirical evidence from the city of Nanjing

This paper provides first-hand empirical evidence about the differentiation of housing conditions among China’s urban poor families based on a case study of Nanjing. The main findings include: (1) the Hukou family registration system has strong differential effects on poor families’ housing conditions; (2) housing conditions among the urban poor are tightly associated with privatization and home ownership, where non-owners face more severe housing difficulties than nominal owners; and (3) resettlement has played a positive role in improving the poor’s housing conditions, but its positive effects are only present in cases where work units or the government has taken the responsibility of housing the resettled poor. These findings show that housing the urban poor in post-reform China is largely: (1) path-dependent, (2) privatization-oriented, and (3) development-driven, and a mechanism that can pro-actively ensure the poor’s basic right to housing is still lacking.     

Value of scenic views: Hedonic assessment of private housing in Hong Kong

Diverse landscape elements in cities are valued differently by residents. People are willing to pay a premium for attractive views. This study assessed the amenity value of two major types of natural landscape in Hong Kong: harbor and mountain. The study was based on 1474 transactions in 2005 and 2006 in 18 private housing estates in a residential district. The high-rise and high-density blocks were typical for middle-income housing in the city. The hedonic pricing method was employed to estimate the proportional share of various views and factors on transaction prices. Only harbor view was preferred and reflected in housing value. A broad harbor view could increase the value of an apartment by 2.97%, equivalent to US$ 15,173. Even a confined harbor view could lift price by 2.18% or US$ 11,137. On the contrary, a broad mountain view would depress apartment price by 6.7%, whereas a confined mountain view was statistically insignificant. Increasing distance between an apartment and a preferred natural landscape would lower transaction price. The negative perception of street view induced a price reduction by 3.7%. Building views were tolerated as an inevitable feature of the compact and vertical city. Quantifying the value of nature and scenic endowments in cities could inform policies and strategies on urban planning, development, nature conservation, and property appraisal.     

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.     

The role of agroforestry networks in landscape socioeconomic processes: the potential and limits of the contingent valuation method

Agroforestry networks can be a means to achieve landscape amelioration. Some authorities of the Lagoon of Venice drainage basin (Italy) are planning, amongst other actions to control pollution in the Lagoon, to reintroduce agroforestry by means of a GIS-supported design procedure. The goals of this paper were to assess (i) the contingent valuation (CV) (willingness to pay and willingness to accept) of agroforestry networks and its relationship with socioeconomic and agroforestry role variables, (ii) the coherence between agro-economic policies and farmers expectations, (iii) the relationship between the value of agroforestry as a “shared good” and water quality (non-point source pollution). Respondents associate a positive value/preference to the agroforestry network implementation, although this value is strongly affected firstly by their identity with the landscape and secondly by their income. The motivations of farmers’ evaluation are precise and the agroforestry network is considered not only as an “ethical object” but also as a concrete element of their own cultural and economic world. In this case the contingent value (in particular, in terms of acceptance) increases with the farmer’s economic capacity, and the farmer’s valuation is not linked only to the “good” but also to the “service” offered for implementing it. The expectations of farmers regarding an agroforestry plantation were lower than European Union incentives at the time of survey, and a lack of results in this field is probably linked to poor information and to bureaucratic difficulties. Even if there is general knowledge on water quality, there is little awareness on the non-point source pollution control effect of agroforestry buffer plantations, either in the common people or in those who are environmentally trained (e.g. planning university students). In every case the agroforestry “shared good” evaluation is high enough to permit efficient and supported intervention policies. These results confirm that landscape choices strongly involve issues of identity, perceived rights and evaluation capacity that cannot be simply resolved in terms of preference cost benefit analyses, but a clever use of the CV allows an identification of these same limitations and a partial estimation of them.     

Accumulating characteristics of platinum group elements (PGE) in urban environments, China

The three-way catalytic converters [mainly using platinum, palladium and rhodium of platinum group elements (PGE)] have been widely used to reduce the pollution arising from vehicular traffic. Since the late 1990s, the Chinese government has implemented measures for new vehicles, equipped with the three-way catalytic converters in metropolitan cities. However, the PGE spreading on environments has not been strongly concerned in developing countries. This study investigated the accumulation characteristics of PGE in urban environments in China. A few samples from India were also analyzed and compared with those from China. The collected soil, aerosol and plant samples were determined for PGE by inductively coupled plasma-mass spectrometry (ICP-MS) after nickel sulphide fire assay preconcentration. The results have shown higher PGE contents in the samples from the cities where vehicles were fitted with autocatalysts for longer time periods. The highest values are 160 ng/g for Pt, 107 ng/g for Pd and 34.5 ng/g for Rh in Hong Kong soils, whereas the lowest values are 2.59 ng/g for Pt, 1.31 ng/g for Pd and 0.40 ng/g for Rh in Kolkata soils. In Beijing and Guangzhou aerosol samples, the PGE concentrations are 6.22 to 24.3 pg/m³ for Pt and 1.16 to 8.60 pg/m³ for Rh and 7.68 to 12.2 pg/m³ for Pt and 2.15 to 5.15 pg/m³ for Rh, respectively. The levels of PGE abundances in the urban environments of China have been significantly elevated with increasing number of vehicles equipped with autocatalysts.     

浅议城市绿地系统建设中的树种规划

在进行城市绿地系统规划时，应在充分调查分析诸如地质地貌、土壤、现状植被和自然气候等自然条件的基础上，选出适生树种，再按群落学原理进行种类搭配。这种方法对建设以生态环境保护为主要功能的城市绿地生态系统，具有重要意义。树种规划中，同样应考虑树种的生态习性变化和观赏特点的多样性，这样会更有助于城市生态环境保护、城市生物多样性保护和环境美化的有机统一。     

Measuring the urban competitiveness of Chinese cities in 2000

Previous studies have understood urban competitiveness mainly from an economic perspective. Drawing on insights from recent debates on urban governance that argue for sustainable development, this study employs a more balanced view that takes into account the economic, social, and environmental dimensions of urban competitiveness. A four-level hierarchical indicator system is used to examine the competitiveness of 253 Chinese cities at the prefecture level or above in the year 2000. The results show that most of the top 20 cities are in the eastern part of China and have populations over 0.5 million. The bottom 20 cities are located primarily in the western part of China and have smaller populations that range from 0.2 to 0.5 million. In 2000 the city with the top economic competitiveness was Shanghai, the top social competitiveness was Beijing, and the top environmental competitiveness was Zhuhai. A given city does not necessarily rank the same in economic, social, and environmental competitiveness, but may perform well in different ways. The paper argues that, in order to sustain urban competitiveness, a city should achieve not only good economic performance, but also satisfactory social and environmental development.     

Valuation of the historic environment: The scope for using economic valuation evidence in the appraisal of heritage-related projects

In this paper we consider the question, ‘What is the the scope for using results of economic valuation studies in the appraisal and assessment of heritage-related projects and programmes?’ This entails assessing the potential role and scope of ‘value transfer’, which is an approach to economic valuation that uses results of previous valuation studies (for example, travel cost or stated preference studies) in the appraisal of projects and programmes. A distinct appeal of value transfer is its expediency and value for money properties in relation to commissioning original valuation studies, which can enable greater use of economic values within decision making. Its potential role in the appraisal of heritage assets depends on whether it is deemed a reliable approach to economic valuation, and whether there is a sufficient body of economic valuation literature concerning the heritage sector. Correspondingly, we examine: (i) the applicability of economic valuation to the historic environment; (ii) the basis for value transfer; and (iii) the literature pertaining to the valuation of the historic environment. We also develop a case study, which demonstrates the use of value transfer in a heritage context. Overall there currently appears to be limited scope for value transfer applications in heritage-related appraisal and evaluation exercises. This is in part due to the heterogeneity and complexity of heritage assets. However, a more fundamental constraining factor is the current extent of heritage valuation literature; only 30 valuation studies were identified relating to the historic environment. We recommend that future work focuses on developing a database of valuation studies relating to the heritage sector, and on establishing a broader base of high-quality original heritage-related economic valuation studies. Moreover, where value transfer is applied in an appraisal and evaluation context to heritage assets, much emphasis should be placed on satisfying the criteria for identifying suitable valuation evidence from existing studies.     

中国城市规划理论及相关期刊述评

中国城市规划实践已到了“归纳、总结、锤炼、提升”的时候,着力构建适合中国国情,城市化特点与城市问题的城市规划理论成为时势所需。研究中国的城市化特点,立足于中国特色的城市问题,城市规划理论的发展必须跳出传统城市规划的狭小圈子,在更大的范围内思考城市,汲取更多相关边缘学科的营养,将建筑学的工具理性与地理学的地域思维相结合,并融合经济学、社会学、管理学、生态学的人文关怀,城市规划理论才会不断创新。众多城市规划类期刊必将担当起城市规划理论创新与实践探索的但是导者和传播者的角色。     

Game theory based models to analyze water conflicts in the Middle Route of the South-to-North Water Transfer Project in China

This study applied game theory based models to analyze and solve water conflicts concerning water allocation and nitrogen reduction in the Middle Route of the South-to-North Water Transfer Project in China. The game simulation comprised two levels, including one main game with five players and four sub-games with each containing three sub-players. We used statistical and econometric regression methods to formulate payoff functions of the players, economic valuation methods (EVMs) to transform non-monetary value into economic one, cost-benefit Analysis (CBA) to compare the game outcomes, and scenario analysis to investigate the future uncertainties. The validity of game simulation was evaluated by comparing predictions with observations. The main results proved that cooperation would make the players collectively better off, though some player would face losses. However, players were not willing to cooperate, which would result in a prisoners' dilemma. Scenarios simulation results displayed that players in water scare area could not solve its severe water deficit problem without cooperation with other players even under an optimistic scenario, while the uncertainty of cooperation would come from the main polluters. The results suggest a need to design a mechanism to reduce the risk of losses of those players by a side payment, which provides them with economic incentives to cooperate.     

东北地区城市建筑的发展与特色

由于自然、社会、文化因素的影响,东北城镇具有寒地性、边疆性、资源性、工业性、铁路主导性和文化融合性等基本特色,而城市中的建筑与建筑群则具有阳光院落、规整外廓、实体墙面、坡式屋顶、偏暖色调、公共空间室内化和地下空间利用等共性特征。东北城市建筑的特色是由于其处于中华文化边缘区所必然形成的混交文化在城市建筑文化中的反映。文章针对当前城市建筑特色建设的问题,提出了相应的对策,并特别强调增强文化个性与魅力,是提高城市综合竞争力的重要途径。