Households’ perceptions of private sector municipal solid waste management services: A binary choice analysis

The increase in the volume of waste materials discharged to the environment and deterioration of environmental quality in urban areas have been an issue of major concern for many governments in developing countries. To improve effectiveness and efficiency in the delivery of waste management services some of the governments have involved the private sector. This study uses binary choice model to examine urban residents’ perceptions regarding solid waste management that involves the private sector and what could be done to improve the waste management services. The data were generated from survey conducted in 238 households in Ilorin in southwest Nigeria. The results show that most of the respondents were not satisfied with solid waste management in the Ilorin. Binary logit model estimates reveal that the respondents’ perceptions regarding waste management were determined by income, travel time to dump site and marital status, as well as awareness of laws regarding waste disposal and activities of sanitary inspectors. For solid waste management in urban areas to be sustainable, it requires participation of the government, private sector and residents. The results generated from this study can help waste management authorities in designing a more sustainable waste management strategy in Ilorin, as well as in other cities that have similar conditions.     

Municipal solid waste landfill site selection using geographical information systems: a case study from Çorlu,Turkey

The rapid population growth due to fast urbanization in developing countries leads to environmentally sustainable and efficient management of solid waste. Insufficient solid waste landfill sites, in particular, require new areas because of rapid urbanization. This reveals the need to select appropriate landfill sites, in terms of pollution, that meet the requirements of curbing pollution. In this study, a new solid waste site selection tool was presented for the assessment and selection of areas for a municipal solid waste (MSW) landfill using a combination of point count index and constraint overlaying method with a geographical information system (GIS). For this purpose, factors affecting the site selection tool development were gathered under three groups, namely geological and natural, environmental and social–economical. For the first group, weighting for each criterion—depending upon its relative importance—was assigned, and ratings were given appropriately with their relative magnitude of impact. For the second and third groups, buffer zones were created in order to perform overlay analysis. This tool was used to perform MSW landfill selection of Çorlu District. According to the final map produced with this tool, two areas were identified within the district limits. This procedure was time saving as it was quite easy and did not require too much time and money to collect data. However, besides the usefulness of the procedure, at the final stage of decision-making, some further investigations should also be made.     

A municipal solid wastes planning model for a metropolitan area

In this paper it will be shown how the problem of solid wastes collection and disposal can be formulated as a dynamic mixed-integer linear programming model. The developed model can be used for the determination of sites for landfills, transfer stations, recycling centers and the periodical routing of collection vehicles in order to reduce the cost of municipal solid wastes transport and disposal. The model has been tested by applying it to a hypothetical municipal solid waste system. The possibility of using the developed model for managing and planning the municipal solid wastes system of the Dammam metropolitan area, Saudi Arabia will be discussed.The model is general in structure and can be used to address other problems such as the problem of hazardous wastes management, petroleum products distribution and food processing industries.     

From labour lines to urban living: Health transition in Mauritius

Recently Mauritius has witnessed a rapid urbanization process. In such a small space, with a high population density and an improving economic situation — shifting from an agricultural-based to an industrial one — it is possible nowadays to distinguish the growth of major villages into well-structured urban centres. Contrary to the trend observed in some economically less developed countries (LDCs), health characteristics have veered mostly towards trends exhibited by economically more developed countries (MDCs). This paper will describe briefly the urbanization processes at work in Mauritius and will explore the changing health characteristics and provisions observed in such a small island state. It will try to lay the foundation for comparison with other small island states transcending the MDC/LDS divide.     

Missing links in solid waste management in the Greater Accra Metropolitan Area in Ghana

In recent years, solid waste management (SWM) policies and programmes have received lots of attention in the menu of most political leaders in developing countries. However, these concerns often focus on the efficiency criterion. Even that, efficiency is only narrowed down to the removal of waste from residential areas without much concern for either its safe disposal or its impact on the environment in case of improper waste disposal. There is little attention on reducing waste flows (through reuse, recycling and composting), or exploiting its economic value. The results of such blatant omission include threats to public health, environmental deterioration and lack of attention to waste as a resource. This study examines the key barriers to effective SWM practices in the Greater Accra Metropolitan Area and attests to the marginalization of waste treatment and disposal practices. It recommends that these missing links must be addressed through network service arrangements to ensure sustainable urban environment management.     

Intra-urban patterns of domestic solid waste recycling in sub-Saharan Africa: towards an exploratory search for insights in Gaborone,Botswana

Botswana is among those developing countries that are rapidly transitioning from predominantly rural to urban societies. Gaborone, its capital city, is seriously confronted by formidable challenges of sustainable metropolitan management, including the proper handling of solid domestic waste. Although the international convention of the 3-Rs, namely, Recycle, Reduce, Reuse is generally accepted; its implementation remains elusive. It is therefore of utmost importance to unravel significant determinants of the gap between nominal acceptance and praxis in order to influence policy. This preliminary case study, consequently, sought to identify the underlying factors that differentiate waste recycling practices from high, medium, and low socio-economic areas Gaborone. Key informants, including municipal officials and company representatives, in charge of city solid waste management, were interviewed. A probit model was used to analyze those factors that could influence recycling and waste separation practices. Results showed that tenure, gender, income, affluence, location of house increase the likelihood of recycling while age, education level, household size and source of waste management information did not influence the likelihood of recycling. Stakeholders should place greater emphasis on positive environmental awareness, and appropriate reward systems for recycling domestic solid waste and recycling should be tailored according to the locational needs.     

Landfill site selection using combination of fuzzy logic and multi-attribute decision-making approach

During the last decades, growth of urbanization and industrialization led to an increase in solid waste generation. Landfilling is the most prevalent ultimate disposal method for the municipal solid wastes in developing countries. The rapid municipal solid waste generation in Markazi province (central part of Iran) causes the need for precision in finding a suitable landfill site selection. In the present study, 12 factors (environmental and socioeconomic factors) have been applied to select the landfill site in Markazi province, Iran. The different methods including the analytic network process (ANP) combined with fuzzy linguistic quantifier, ordered weighted average (OWA), and weighted linear combination (WLC) approach in geographic information system was applied to find an appropriate landfill site. The OWA operator function permits the evaluation of the wide spectrum of consequences (with different scenario) obtained from different management strategies. Results revealed that integration of fuzzy logic, ANP, and OWA provides flexible and better ideas compared to the Boolean logic and WLC to select a suitable landfill site.     

A model for gas pressure in layered landfills with horizontal gas collection systems

The recovery and emission of landfill gas (LFG) is an important topic in landfill management. To produce an effective engineering design for an LFG collection system, designers must understand the migration of gas from the waste body to horizontal extraction wells. This paper develops a two-dimensional analytical solution to enable the study of the gas pressure distribution, well pressure and recovery efficiency in layered landfills with horizontal wells. A horizontal layered structure is used to accommodate the non-homogeneity of various municipal solid waste (MSW) aspects with respect to depth, including gas generation, permeability and temperature. The governing equations, subject to boundary and continuity conditions, are solved by using separation of variables and double finite integral transforms. The solution was verified against another analytical solution and a numerical simulation. Subsequently, a sensitivity analysis of single-well model parameters is performed to optimize a double-well system. The results show that a landfill with horizontal collection systems cannot be assumed to be one dimensional with increasing well spacing. Additionally, both the operational vacuum and maximum gas pressure can be reduced through the design of a double- or multiple-well system. Therefore, the proposed solution can be used for the verification of more complex models and the preliminary design of a horizontal well system.     

Why Delhi cannot plan its ‘new towns’: The case of solid waste management in Noida

Indian metropolises have witnessed the growth of ‘new towns’ on their peripheries over the past two decades, which have attracted investment as well as affluent residents. Most research on new towns examines the contentious politics of land acquisition and development, but less is known about urban governance and everyday life. This article focuses on solid waste management in Noida, a new town on the periphery of Delhi that has been unable to develop a large-scale waste management system, and we have two main foci. First, we show that the municipal government has sought to regulate waste collection, while waste processing and disposal have remained unregulated and this has discouraged the entry of medium and large-scale private enterprises. Second, we explore the contentious politics surrounding actually existing waste management practices that have emerged in the absence of significant public or private investment. Most waste is managed by small- and medium-sized enterprises in the informal sector, so associations that represent the so-called ‘new’ middle class must interact with informal-sector waste workers. These interactions result in moderately high levels of waste collection but waste disposal remains haphazard and this exposes the limits of the new middle class’ control over urban space. Ultimately, we show how municipal governance and the actually existing politics and practices of waste management contribute to the production of Noida’s socio-spatial landscape.     

Geographic aspects of urbanization and its peculiarities in countries with different social systems

The complex process of urbanization is obtaining under the impress of scientific and technological revolution of global dimensions. But the process of urbanization depends very much on geographical differentiation of the factors and conditions on the Earth' surface. So it is deeply geographical in its essence. It is not only geographically conditioned but it also has deep spatial manifestations, which makes it one of the most important and universal fields of investigation for the whole system of geographic sciences. The common global features and general regularities of urbanization take peculiar forms in each of the three main groups of countries having different social systems: socialist, economically developed capitalist and developing, which leaves its deep imprints not only on the social contents of urbanization but also on the very process of forming of specific spatial-urbanistic structures, existing on the Earth. To this we should further add the results of working of individual traits of different countries and regions. So to get the real pattern of world urbanization it is necessary to study profoundly not only its global and typological features but also the specific local factors. To these ends geographers must elaborate a system of basic notions and characteristics of the urbanization process and stage. Some of them are treated in this paper.     

城市固体垃圾填埋场选址的地质条件评价

随着我国工业化、城市化进程的加快,不断增长的城市垃圾及处置问题日益突出。卫生填埋是现阶段处理城市垃圾的主要方法。做好填埋场的地质条件研究,对填埋场选址及建设甚为重要。探讨城市固体垃圾填埋场选址应注意的地质问题,对其地质条件进行了分析和评价;根据GIS的技术特点及在填埋场选址中的具体应用,提出了解决问题的建议与对策。     

Spatial inequality in municipal solid waste disposal across regions in developing countries

The regional inequalities in socio-economical characteristics such as income, population density, age composition, unemployment rate and the education level may bring about variation in waste generation, recycling and collection. Using environmental Kuznets curve, the factors affecting municipal solid waste disposal are examined. The results demonstrate that an inverted N-shaped curve executes on municipal solid waste disposal for all regions. As personal disposable income increases, per capita municipal solid waste disposed firstly declines, then grows at the second stage and finally decreases again. All the explanatory variables including economic factors, social characteristics and geographical barriers are found to influence municipal solid waste disposal significantly. Each person increase in population density leads to an increase in municipal solid waste disposed by approximately 1.17 ×10^?4 kg/day. Each percent increase in age composition results in a decrease in municipal solid waste disposed by approximately 0.0224 kg/day; in the unemployment rate causes a decrease of 0.0901 kg/day and in the education level results in a decrease of 0.01556 kg/day. In general, municipal solid waste disposal starts to increase at the first turning point of personal disposable income NT$ 198,000 (about US$ 6,280) and to decrease at the second point of NT$ 389,000 (about US$ 12,350) for all regions (pooled data). The rural regions, however, cannot support the inverted N-shaped curve by the ‘reduced form’ while urban regions have a significant outcome. This result implies that income can only explain a portion of variation while other social and geographical factors contribute a lot to identify the variation in municipal solid waste disposal between urban and rural regions.     

城市地下空间开发面临的机遇与挑战

随着我国社会经济的发展和城市化进程的加速,我国大城市土地资源变得紧缺。各要素的高度集聚出现各种矛盾,城市空间容量供需矛盾日益突出,使得地下空间开发的需求日趋明显,这也为城市地下空间开发带来机遇,但同时也面临种种挑战。本文从目前政策法规、开发现状及用途等存在问题入手,结合国外发达国家地下空间开发模式,提出我国城市地下空间健康发展的解决之道,以此展望我国城市地下空间发展前景。     

岩溶区地下水微生物污染特征及来源——以重庆南山老龙洞流域为例

文章选取老龙洞地下河流域10个地下水点采集样品,分析水样中的水化学指标和三种重要微生物指标,以了解城市化进程对老龙洞地下河流域水质的影响,探究该地区微生物污染的主要来源。结合岩溶区独特的水文地质条件,利用粪大肠杆菌（FC）与粪链球菌（FS）比值法,初步分析得到该地区微生物污染程度和污染来源。研究结果表明:（1）老龙洞流域地下水存在严重的微生物污染,地下水总细菌数、大肠菌群远超过国家地下水标准规定,分别是国家地下水标准规定的2.3×102～5.5×104倍、0.8×104～0.9×106倍,粪大肠菌群数量为100～4.38×106 CFU?L-1;（2）4#、6#采样点微生物污染主要来源于温血动物,1#、7#、8#采样点地下水受城市化进程的影响大;（3）微生物污染主要来源于人类粪便,同时SO42-、PO43-、NO3-含量高且与微生物污染相关性密切,说明生活污水引起的次生微生物污染较严重,2#、3#、5#、10#采样点受生活污水和禽畜粪便影响较小,属于单纯的NO3-农业污染型地下水,微生物污染较轻。      

江西省城市化水平与城市效率相关分析

在对江西省城市化水平分析的基础上,应用城市效率指标,对江西省11个地级市的城市效率作了定量分析,总结了其地域分异规律,并就江西省城市化水平与城市效率进行了相关分析研究。结果表明,江西省的城市化水平与城市效率的相关性总体一致,符合“城市规模效率梯度”现象。在提高城市集聚功能,培育城市群（带）,促进城市可持续发展以及欠发达地区的发展方面提供了一些有益的参考和建议。     

The nature of urbanization in the gulf countries

This paper analyses the urban process in the oil producing countries of the Gulf. The mode of urbanization is identified as one characterized by an extreme case of primacy but with rates varying among the countries of the region. This pattern is related to the historical evolution of human settlements as affected by the local environmental qualities and the recent large scale development of urban infrastructures which favoured the already existing capital cities. The relative city growth rates are among the highest in the world but with a declining tendency which reflects expenditure patterns and the nature of the regional economies. The high growth rates are essentially due to massive foreign migration into the region and to extremely high natural increase rate — an abnormal condition in an urban process approaching saturation point. The role of these primate centres in the development of the region is undeniable and, furthermore, all indications suggest that this pattern of urban development will continue in the furture as it is, perhaps economically and politically less costly.     

The urban political ecology of plastic bag waste problem in Nairobi, Kenya

Over 24 million plastic bags are consumed in Kenya monthly. More than half of the bags end up in the solid waste stream. Plastic bags now constitute the biggest challenge to solid waste management in Nairobi, the capital of Kenya and home to three million people. As a result, plastic bag waste has attracted great political and public attention, especially because the waste has myriad unique environmental problems. This paper seeks to unravel the problem of plastic bag waste in Nairobi through an urban political ecological perspective. Urban political ecology has done much to excavate economic, political, and cultural processes, as well as ecological dynamics that create and re-create urban environments. Little has been done in this context with respect to urban solid waste problems, with the exception of urban political ecology of environmental justice. However, research done within the context of urban political ecology of environmental justice has mainly focused on solid waste problems in the Western World, particularly USA. Drawing on research conducted in Nairobi, as well literature on business and politics, and solid waste management in Kenya, this paper examines the nature of plastic bag waste problem, its political–economic roots and implications for environmental justice.     

Impact of city expansion on hydrological regime of Rispana Watershed,Dehradun, India

Rispana River flows through the heart of Dehradun, the capital city of Uttarakhand State, India. Uttarakhand had separated from Uttar Pradesh State in the year 2000; since then, Dehradun City has witnessed numerous changes. Both urban sprawl and densification were noticed, with around a 32% increase in population. The city had faced recurrent high runoff and urban flood situations in these last 2 decades. Therefore, the study was conducted to detect the change in land use/land cover (LULC), especially urbanization, through remote sensing data; and later to determine the impacts of such changes on the Rispana watershed hydrology. The LULC maps for the year 2003 and the 2017 were generated through supervised classification technique using the Landsat Series satellite datasets. The LULC change analysis depicted that mainly the urban settlement class increased with significant area among other classes from the year 2003–2017. It was noticed that majorly agriculture and fallow land (8.18 km², which is 13.52% of total watershed area) converted to urban, increasing the impervious area. Almost all the municipal wards, falling in the Rispana watershed, showed urbanization during the said period, with an increase of as high as 71%. The change in LULC or effect of urbanization on the hydrological response of the watershed was assessed using the most widely used Natural Resources Conservation Services Curve Number method. It was noticed that the area under moderated runoff potential (approx. 10.23 km²) steeply increased during the lean season, whereas, high runoff potential zones (5 km²) increased significantly under wet season. Therefore, it was concluded that an increase in impervious surface resulted in high runoff generation. Further, such LULC change along with climate might lead to high runoff within the watershed, which the present storm drainage network could not withstand. The situation generally led to urban floods and affected urban dwellers regularly. Therefore, it is critical to assess the hydrological impacts of LULC change for land use planning and water resource management. Furthermore, under the smart city project, the local government has various plans to improve present infrastructure; therefore, it becomes necessary to incorporate such observations in the policies.

     

北方寒冷地区城市哈尔滨人口城市化与土地城市化协调关系研究

以哈尔滨市为研究范围,构建了人口城市化、土地城市化指标体系,运用熵值法计算各指标的权重,结合协调发展模型,分别研究了哈尔滨市1997-2014年期间人口城市化的内部协调性、土地城市化的内部协调性以及人口城市化和土地城市化的协调度及协调发展水平,并对人口城市化、土地城市化与协调发展水平进行了研究。结果表明：哈尔滨市的人口城市化内部协调性和土地城市化内部协调性都表现出前期加速,后期平稳的状态,在20世纪90年代,人口城市化内部协调性和土地城市化内部协调性都迅速提高,进入21世纪以后,协调度均保持在0.9左右,波动较小,内部协调度较高;综合人口城市化和土地城市化的协调度和相对发展度来看,除1999-2000年处于高级协调外,在研究期的其余时段哈尔滨市人口城市化和土地城市化基本处于初级协调状态,人口城市化与土地城市化的非同步性,是制约两者协调发展的关键因素,其中人口城市化对协调发展水平的影响更大。     

Comparative urbanization in Ghana and Kenya in time and space

There are few inter-African country urban analyses because of the continent’s enormous size and socioeconomic diversity, language barriers, and wide variations in national and regional urban research capacity. Nevertheless, comparative urban studies are critical in understanding contemporary African urbanization. In this comparative spatial and temporal analysis of Ghana and Kenya’s urbanization, we find that both countries are urbanizing rapidly and are faced with many common urban problems. Moreover, Ghana is more urbanized than Kenya and has a larger indigenous urban imprint and a more widely dispersed urban pattern. Besides their physiographic and population conditions, we trace these countries’ convergent and divergent urban trends to their shared but unique experiences of colonialism, nationalism and globalization.