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1.
Rainwater has been used in many countries as a way of minimising water availability problems. In Brazil, it has been reported that the potential for potable water savings by using rainwater may range from 48% to 100% depending on the geographic region. In southeastern Brazil, water availability is about 4500 m3 per capita per year, but it is predicted to be lower than 1000 m3 per capita per year from about 2100 onwards. The main objective of this article is to evaluate the potential for potable water savings by using rainwater in 195 cities located in southeastern Brazil. Rainwater tank sizes are also assessed for some cities in order to evaluate the ideal tank capacity as a function of potable water demand and rainwater demand. Results indicate that average potential for potable water savings range from 12% to 79% per year for the cities analysed. Ideal rainwater tank capacities for dwellings with low potable water demand range from about 2000 to 20,000 litres depending on rainwater demand. For dwellings with high potable water demand, ideal rainwater tank capacities range from about 3000 to 7000 litres. The main conclusion drawn from the research is that the average potential for potable water savings in southeastern Brazil is 41%. It was also concluded that rainwater tank capacity has to be determined for each location and dwelling as it depends strongly on potable water demand and rainwater demand.  相似文献   

2.
Traditional villages in China show a pattern of ‘self-organization’. There is unplanned overall layout of space elements within the village landscape. Since the ‘Building a New Countryside’ policy, professionals have been active in design of the village landscape. The first step is to identify the distinguishing features of the traditional village landscape. This paper aims to identify the distinguishing features of village landscape compared with an urban residential area. The results indicate that abundant plants, shabby houses, monotonous colour, badly-maintained environment and closed space are the distinguishing features. A clean environment and high vegetation coverage are important.  相似文献   

3.
Chen B  Xuan X  Zhu L  Wang J  Gao Y  Yang K  Shen X  Lou B 《Water research》2004,38(16):3558-3568
Ten polycyclic aromatic hydrocarbons (PAHs) were simultaneously measured in 17 surface water samples and 11 sediments of four water bodies, and 3 soils near the water-body bank in Hangzhou, China in December 2002. It was observed that the sum of PAHs concentrations ranged from 0.989 to 9.663 microg/L in surface waters, from 132.7 to 7343 ng/g dry weight in sediments, and from 59.71 to 615.8 ng/g dry weight in soils. The composition pattern of PAHs by ring size in water, sediment and soil were surveyed. Three-ring PAHs were dominated in surface waters and soils, meanwhile sediments were mostly dominated by four-ring PAHs. Furthermore, PAHs apparent distribution coefficients (K(d)) and solid f(oc)-normalized K(d) (e.g. K(oc)= K(d) / f(oc)) were calculated. The relationship between logK(oc) and logK(ow) of PAHs for field data on sediments and predicted values were compared. The sources of PAHs in different water bodies were evaluated by comparison of K (oc) values in sediments of the river downstream with that in soils. Hangzhou section of the Great Canal was heavily polluted by PAHs released from industrial wastewater in the past and now PAHs in sediment may serve as sources of PAHs in surface water. PAHs in Qiantang River were contributed from soil runoff. Municipal road runoff was mostly contributed to West Lake PAHs.  相似文献   

4.
This paper deals with industrialization in Italy between 1871 and 2001, and is based on data on the labour force per province (NUTS 3) from population censuses. Particular attention is devoted to long‐term trends and North–South disparities. After the analysis of the geographic spread of industry and its changes, we test the role of access to markets on the distribution of the labour force in manufacturing. The results show that access to markets played a main role in Italian industrialization and in the evolution of inequalities among Northern and Southern regions.  相似文献   

5.
According to the Water Authority of Israel, Israel's water economy is on the brink of a crisis. Demands are increasing, exceeding the capacity of the natural sources, which are being depleted. Water, as a resource in short supply, necessitated administrative actions in order to attain its efficient utilization, in accordance with the goals set by the state. In addition, the issue of water allocation in Israel is strongly connected to internal politics and not necessarily to a clear overall policy. This article presents a simulation model which examined a large number of different scenarios and returns the possible outcomes of water allocations in a routine situation of uncertainty. The findings show that even under ideal conditions, a water shortage in Israel is inevitable and urban consumption will demand the largest allocation of water. As a result, the Israeli rural sector will be required to reorganize the water allocation system and production structure.  相似文献   

6.
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.  相似文献   

7.
Urban green spaces have important amenity values that include provision of leisure opportunities and aesthetic enjoyment. However, most of these values lack a market price. Consequently, they are usually ignored or underestimated by urban planning policy-makers, with the result that remnant urban green spaces are being gradually encroached upon by urban sprawl. As a result, quantitative information regarding the implicit, non-market price benefits from urban green space is urgently required. Properties bought and sold on the market are compound commodities that embody amenity values and people are willing to pay to live in the proximity of local amenity environment. Thus hedonic models, which use such properties as proxies, can often be employed to quantify environmental amenities. In China, residential housing reform (in place since 1998) has terminated the traditional residential welfare system, and made it possible to quantify the monetary value of green space amenities based on hedonic pricing models. This study was conducted in Jinan City, and will help address the previous absence of the application of hedonic price models to the valuation of urban green space amenities in mainland China. GIS and landscape metrics were used in determining hedonic price model variables. As expected, the results proved that the hedonic pricing model performed well using this approach, and accordingly it was further improved. Results also confirmed the positive amenity impact of proximate urban green spaces on house prices, and highlighted the preferences of homeowners in Jinan City. Green space amenity variables that were statistically significant at the 5% level included the size–distance index of scenery forest, accessibility to park and plaza green space types, and the percentage of urban green space. In addition, land-use patch richness, the location sector and the education environment also proved to be highly significant variables. The results of the study should provide insights to policy-makers involved in urban planning.  相似文献   

8.
The purposes of this research are to contrast the energy use characteristics of old residential buildings and new residential buildings in Shanghai, China, to look into influence factors of residential energy consumption, and to further analyze the reasons which result in the differences of energy consumption quantities between high-energy use family group and low-energy use family group. 1610 families in Residential District A and 819 families in Residential District B were chosen to trace their monthly energy consumption data in the whole year of 2006. Buildings in District A were all constructed in the 1980s, while those in District B were built in the 2000s. 300 families in each district were further selected from all above investigated families to do questionnaires in the year of 2007, so as to understand building characteristics, the possession and utilization of space heating and cooling appliances, and energy-saving consciousness. Annual energy consumption of the two kinds of buildings is contrasted and energy consumption quantities of spacing cooling and heating are also calculated. Influencing factors of residential energy consumption are analyzed by Quantification Theory I. Quantification Theory III is used to classify all the families into different categories based on the differences in their energy consumption amounts, and to further find out the reasons leading to the different energy consumption between different groups. Conclusions are as follows: (1) the average annual energy consumption quantity is 23.27 GJ/household for new buildings and 14.40 GJ/household for old buildings. The ratio of space heating and cooling to total annual energy consumption is just 16% and 11.6% for new buildings and old buildings respectively; (2) energy consumption and its variance lie on the integration of many factors, such as the floor area, materials of window frames, the number of family members, operation months of space heaters in winter and air conditioners in summer, and energy-saving actions; (3) all the families in the two districts can be classified into two categories: Household Region M of much energy use, and Household Region N of little energy use. Adopting the aluminum window frames, large floor areas and the large number of family members (above 4 person) are the main reasons leading to more energy use in Household Region M, while the small number of family members (1-2 persons/household) and small floor areas are the main reasons resulting in the less energy use in Household Region N; the long period of space heating, using illumination as little as possible are also the reasons causing the differences in energy consumption quantities between the two categories, but their influences on the samples clustering are smaller than the main reasons above; (4) compared with the energy consumption in some developed countries, the ratio of space heating and cooling to total residential energy use is much smaller in Shanghai. Indoor thermal environment is very poor besides that. With the growth of economy and the improvement of living standard, people will have the higher requirement for good-quality indoor thermal environment, and hence space heaters and coolers will be used much more frequently, so the residential energy consumption in China will still continuously increase rapidly, if few energy-conservation strategies are adopted; (5) considering current little prevalence of energy-saving actions with low efficiency, more effective energy-saving actions should be fully adopted in China.  相似文献   

9.
5·12汶川地震绵阳市区房屋震害统计与分析   总被引:1,自引:0,他引:1  
历次大地震的经验总结是推动建筑抗震技术发展的重要途径。通过绵阳市区房屋在汶川大地震后的震害应急评估和调查,对市区各类房屋结构的震害进行了统计,总结分析各类房屋的震害特征和经验教训。得到一些启示和建议:绵阳市区按现行抗震规范设计的房屋基本经受住了地震考验;不同的结构体系表现出的抗震性能差别较大;老旧房屋始终是抗震薄弱环节,应有选择地进行抗震鉴定加固,开展砖混结构墙体抗震防裂措施研究,采取措施有效减轻框架结构中填充墙等非结构构件的震害,开展楼梯抗震设计计算与构造措施的研究。  相似文献   

10.
The extensive growth in most Chinese cities at the expense of local identities of living settlement. Taking the 60 residential neighborhoods in county-level cities of varied climate zones in China as examples, this paper explores their spatial–temporal changes and differences in morphology, based on 12 morphological indicators through Principal Component Analysis and correlation analysis by ArcGIS 10.2, SPSS 22, and Origin 2021. The results show that 1) the construction dating of the 60 sample neighborhoods conforms to the development of China’s housing reform; 2) the spatial morphology of residential neighborhoods in county-level cities of different climate zones could be charaterized by 5 factors, i.e. neighborhood shape, development intensity, neighborhood size, layout order, and aggregation degree; 3) the disparities in the spatial morphology of residential neighborhoods in the same climate zone in different period of time are mostly indicated with 3 morphological indicators, i.e. Building Density, Neighborhood Area, and Green Space Ratio; rather, the morphology of residential neighborhoods built during a same period of time varies largely between climate zones, mainly indicated with Green Space Ratio, Degree of Building Angle Disorder, and Degree of Building Distance Disorder; and 4) China’s housing policies, climatic conditions, residential building patterns, and the urbanization of each city together influence the spatial–temporal changes in the spatial morphology, offering references to policy making, planning, and construction to protect the regional characteristics in the future.  相似文献   

11.
Guitang River, a once natural river breeding a harmonious human-water relationship, is now the longest inland river of Changsha City, Hunan Province, China, suffering from severer water problems such as water shortage, environmental polloution, and ecological degradation, which heavily impede the urban development. Commissioned by Changsha Guitang River Catchment Development and Construction Co., Ltd., the project team employed 4 mathematic models including a hydrodynamic model of water systems, a water quality model, a hydrodynamic model of drainage networks, and a hydrological model of watersheds to generate an optimal planning scheme for restoring the natural water circulation with the most appropriate planning scheme. Strategies were proposed including the blue and green ecological network combined with urban functional zoning, natural river restoration, riparian space improvement, watershedscale ecological corridor construction, and neighborhood-scale sponge city construction. The whole planning and design, from a coordinated planning at the watershed scale to the river scale, and to specific neighborhood projects, is to establish a social-economic-natural compound ecosystem to balance urban development with ecosystem improvement, while promoting the sustainability of the river.  相似文献   

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