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1.
Summary The major characteristics, problems and prospects of farming in an urban environment of a developing nation are investigated using the Ibadan metropolitan area of Nigeria as a case study. Eight hundred farmers, made up of both part-time and full-time farmers were interviewed in five urban fringe settlements in the study area. Findings revealed that farming in the urban environment is guided by the logic of survival since most of the farmers engaged in urban cultivation are mainly low-income earners and they farm mainly to reduce their expenses on food and to supplement the family's income. The major problem confronting farming in the area is competition from non-agricultural land uses. Nevertheless, more than half (50.5 percent) of the farmers, who had been approached to sell their farmlands for non-agricultural uses in the area, rejected the offer, indicating that the prospects of continued farming are thought to be good. Measures like the sale of urban land at its agricultural value, provided the land remains in cultivation, as well as the further provision of land in and around the farmers' working places, could improve their access to land for extended farming.Dr Adeniyi Gbadegesin is a lecturer in the Department of Geography at the University of Ibadan. He has published papers widely on agricultural topics.  相似文献   

2.
This paper presents a critical assessment of the existing Lebanese industrial sector, namely the current status and classification of industrial establishments based on a comparative synthesis and analysis of recent nationwide surveys and studies pertaining to industrial-waste management. Characterisation of solid and liquid industrial wastes generated, including hazardous wastes, is presented together with current and projected waste loads, recycling opportunities, and export/import practices. Institutional capacity and needs pertaining to the enforcement of relevant environmental legislation, staffing and resources, monitoring schemes, and public participation are critically evaluated. Finally, realistic options for industrial-waste management in the context of country-specific institutional economic and technical limitations are outlined. The industrial sector in Lebanon consists of small-scale industries (84% employ less than 10 persons), primarily involved in light manufacturing (96%). These industries which are distributed among 41 ill-defined zones and deficient in appropriate physical infrastructure, generate solid, liquid, and hazardous waste estimated at 346,730 tons/year, 20,169,600 m3/year and between 3000 to 15,000 tons/year, respectively. Although the growth of this sector contributes significantly to the socio-economic development of the country (industry accounts for 17% of the gross domestic product), in the absence of a comprehensive environmental management plan, this expansion may not be sustained into the coming millennium. The anticipated expansion will inevitably amplify adverse environmental impacts associated with industrial activities due to rising waste volumes and improper waste handling and disposal practices. These impacts are further aggravated by a deficient institutional framework, a lack of adequate environmental laws, and lax enforcement of regulations governing industrial-waste management.  相似文献   

3.
In the last three decades the Nigerian environment has experienced rapid degradation. A major contributory factor of this phenomenon is the pattern of socioeconomic development in the country that gives little or no consideration to environmental outcomes. An aspect of this development is the economic policy of removal of subsidies on petroleum products initiated in 1986 as a result of the worsening economic situation in the country which begun in the early 1980s. The result of this is that prices of commercial fuels inclusive of kerosene and LPG (cooking gas) have continued to rise beyond the reach of majority of the Nigerian population. The paper examines the effect of increasing prices of petroleum-derived energy sources on the pattern of energy use for cooking in low and middle-income households and the environmental implication in Ibadan, the largest truly indigenous urban centre in sub-Saharan Africa. Results show that prior to the further subsidy removal of 1993, majority of households sampled used kerosene for cooking. Thereafter, a complete or partial switch in the pattern of domestic energy consumption ensued with more households using fuel wood and other more polluting and less efficient energy sources for cooking. The paper recommends a transition towards more environmental friendly energy sources for household use.  相似文献   

4.
Soil erosion is accelerating in developing countries of Asia, Africa, and Latin America. It has threatened the livelihood of millions of peasants, for agriculture is their economic mainstay. A probe into the forces causing erosion reveals that the elite’s resolve to accumulate ever more wealth and to maintain, consolidate, or expand their sociopolitical power and the necessity of the poor to fulfill their requirements of food, fuelwood, and fodder are the two major factors accelerating soil erosion. Unless the vast masses of poor people are integrated into the national mainstream through the implementation of equitable and redistributive development policies, it is impossible to control the accelerating rate of soil erosion and thus to achieve the objective of sustainable development. In this article, the phenomenon “soil erosion” is studied with the sol e focus on causation through anthropogenic factors.  相似文献   

5.
The biotopes of ecological importance in urban environments worldwide are under the pressure of many negative factors such as urbanization, air pollution, human disturbance, etc. Biotope mapping is an important tool for urban planning and management and of importance for the protection of biotopes for future generations. The biotopes in Antalya city of Turkey, which has faced to a great population pressure due to tourism developments and immigration in the last two decades, were investigated in this study. The selective biotope mapping method was used and major biotope sites were determined by the interpretation of panchromatic aerial photographs, assisted with field verifications. A sensitivity assessment based on two parameters, the rarity and the re-establishment ability of biotopes, was made as it was considered important information for urban planning and management. According to the results of the assessment, the majority of biotopes in Antalya city were found to be very sensitive or sensitive. It was concluded that insufficient legislation, the lack of an ecological urban planning approach and poor urban management are the most important reasons for today's pressures on urban biotopes in Turkey.  相似文献   

6.
Providing reliable and affordable wastewater treatment in rural areas is a challenge in many parts of the world, particularly in developing countries. The problems and limitations of the centralized approaches for wastewater treatment are progressively surfacing. Centralized wastewater collection and treatment systems are costly to build and operate, especially in areas with low population densities and dispersed households. Developing countries lack both the funding to construct centralized facilities and the technical expertise to manage and operate them. Alternatively, the decentralized approach for wastewater treatment which employs a combination of onsite and/or cluster systems is gaining more attention. Such an approach allows for flexibility in management, and simple as well as complex technologies are available. The decentralized system is not only a long-term solution for small communities but is more reliable and cost effective. This paper presents a review of the various decentralized approaches to wastewater treatment and management. A discussion as to their applicability in developing countries, primarily in rural areas, and challenges faced is emphasized all through the paper. While there are many impediments and challenges towards wastewater management in developing countries, these can be overcome by suitable planning and policy implementation. Understanding the receiving environment is crucial for technology selection and should be accomplished by conducting a comprehensive site evaluation process. Centralized management of the decentralized wastewater treatment systems is essential to ensure they are inspected and maintained regularly. Management strategies should be site specific accounting for social, cultural, environmental and economic conditions in the target area.  相似文献   

7.
Design criteria for planning urban sewerage/excreta management systems appropriate for developing countries as distinguished from affluent industrialized country practices.  相似文献   

8.
Soil erosion in developing countries: a socio-economic appraisal   总被引:12,自引:0,他引:12  
Soil erosion is the single most important environmental degradation problem in the developing world. Despite the plethora of literature that exists on the incidence, causes and impacts of soil erosion, a concrete understanding of this complex problem is lacking. This paper examines the soil erosion problem in developing countries in order to understand the complex inter-relationships between population pressure, poverty and environmental-institutional dynamics. Two recent theoretical developments, namely Boserup's theory on population pressure, poverty and soil erosion and Lopez's theory on environmental and institutional dynamics have been reviewed. The analysis reveals that negative impacts of technical change, inappropriate government policies and poor institutions are largely responsible for the continued soil erosion in developing countries. On the other hand, potential for market-based approaches to mitigate the problem is also low due to the negative externalities involved. A deeper appreciation of institutional and environmental dynamics and policy reforms to strengthen weak institutions may help mitigate the problem.  相似文献   

9.
The twentieth century saw a dramatic increase in the production of urban solid waste, reflecting unprecedented global levels of economic activity. Despite some efforts to reduce and recover the waste, disposal in landfills is still the most usual destination. However, landfill has become more difficult to implement because of its increasing cost, community opposition to landfill siting, and more restrictive environmental regulations regarding the siting and operation of landfills. Moreover, disposal in landfill is the waste destination method with the largest demand for land, while land is a resource whose availability has been decreasing in urban systems. Shortage of land for landfills is a problem frequently cited in the literature as a physical constraint. Nonetheless, the shortage of land for waste disposal has not been fully studied and, in particular, quantified. This paper presents a method to quantify the relationship between the demand and supply of suitable land for waste disposal over time using a geographic information system and modelling techniques. Based on projections of population growth, urban sprawl and waste generation the method can allow policy and decision-makers to measure the dimension of the problem of shortage of land into the future. The procedure can provide information to guide the design and schedule of programs to reduce and recover waste, and can potentially lead to a better use of the land resource. Porto Alegre City, Brazil was used as the case study to illustrate and analyse the approach. By testing different waste management scenarios, the results indicated that the demand for land for waste disposal overcomes the supply of suitable land for this use in the study area before the year 2050.  相似文献   

10.
Summary Flooding has become an inherent problem in most urban centres close to the Nigerian coast. In the last decade it has extended to large settlements in the interior of the country where rainfall is more sporadic. This study has revealed that various socio-cultural activities have promoted flooding in many of these Nigerian urban environments. These activities are characterised by stream or river channel encroachment and abuse, increased paved surfaces and poor solid waste disposal techniques, due to a high level of illiteracy, a low degree of community awareness, poor environmental education, ineffective town planning laws and poor environmental management. Govenment, at various levels, needs to address these issues.His special field of interest is in natural resource management, focusing on the implications of environmental degradation and sustainable development.  相似文献   

11.
There is a growing concern about integrating biodiversity into urban planning, yet, discussions are concentrated on science-informed planning in general. Few have explored the integration of biodiversity in specific planning instruments, especially in African cities. This paper examines how and what components of biodiversity are integrated into master plans, medium-term plans, building codes, zoning codes and permits in Kumasi City, Ghana. There is limited integration of biodiversity in most planning instruments as they were mostly designed on the basis of health, safety and economy. Allied to lack of funding and public participation, biodiversity in Kumasi is under significant threat from rapid urban development. Creating an opportunity for popular participation and decentralizing the planning system could set the preconditions for local integration and revision of instruments. Simplifying the definition of biodiversity could increase local planners’ appreciation, understanding and their ability to make use of biodiversity data.  相似文献   

12.
Traditional approaches to metropolitan management have placed stress upon the achievement of physical and economic growth. In recent years attention has turned to environmental concerns and the achievement of sustainable urban development. It is important to define the objectives for the sustainable development of cities and to identify the principles upon which such development can be based.  相似文献   

13.
Acute toxicity of an acaricide (Nuvan® 1000 EC) in lizards (Agama agama) was observed within 2 minutes spraying of the acaricide in an enclosed dog kennel; heavily infested by ticks in urban area of Ibadan city, South western Nigeria. The acaricide was used at the 0.5% concentration recommended by the manufacturer (Novartis). A lizard which emerged from the kennel during the acaricide spraying exhibited acute signs of toxicity which consisted of shivering, gasping and death. The clinical signs of the acute toxicity manifested in the affected lizard resembled central nervous system (CNS) breakdown or neurotoxicity. Also, two lizards (one female and one male) were found dead in the kennel in the second and third days after the single acaricide spraying operation. The acute acaricide toxicity in lizards observed in this study portrayed the danger of environmental hazard to non-target commensal organisms and it is the first reported case in the area.  相似文献   

14.
In the study of environmental degradation, there has not been sufficient attention paid to the perceptions of the local inhabitants. The importance of traditional beliefs and practices has often been overlooked. This paper looks at traditional and Christian beliefs in Akwa Ibom State in South Eastern Nigeria. Interviews, observations and focus group discussions were used to collect the data. The data analysis shows that knowledge and attitudes are somewhat linked to tradition but also influenced by Christian ideas concerning genesis. There are a number of recommendations made.  相似文献   

15.
ISO 14001:2015 is an international standard that specifies the requirements of environmental management systems (EMS). This study assessed the influence of top management commitment, applications of compliance and other requirements, operational control, monitoring and measurements, resource management and improvements as critical factors on successful implementation and the operation of the ISO 14001:2015, by considering organizations in Sri Lanka as a case study. A data collection was conducted via questionnaires and structured interviews from stakeholders who are directly responsible for the EMS such as environmental managers, quality mangers and general managers of the organizations, who are certified with ISO 14001:2015, and comparisons were undertaken. The statistical analysis of the critical factors has shown a significant positive effect on both large‐scale organizations and export‐oriented organizations on EMS implementation. Furthermore, the results indicate that the EMS adoption has created significant positive impacts on efficient energy and resource consumption within organizations.  相似文献   

16.
Tropical fisheries, which are considered multi-species, may show selectiveness. We analyzed the degree of selectivity of fish catches in 46 sites along the Amazon basin through the percentage of biomass corresponding to the most caught fish species. Amazonian fisheries were considered moderately selective, as 54% of the sites directed more than a quarter of fishing effort to one fish species and in 87% of the sites more than half the fishing effort was directed to five fish species. Commercial fisheries were more selective than subsistence fisheries. Eleven fish species (nine of them migratory) have received more fishing pressure in the studied Amazonian regions and the catch composition differed among regions. We thus recommend that fisheries management in the Amazon basin should distribute fishing effort among more fish species; incorporate the particularities of commercial and subsistence fisheries; evaluate fishing effects on ecosystem services; and consider the biological characteristics of preferred fish.  相似文献   

17.
Farmers attempting to subsist in tropical uplands often rely upon unsustainable resource use practices that lead to soil erosion, declining crop yields, and a loss of soil productivity capacity. Other uses of tropical uplands, including logging and conversion of forest to rangelands, have similar results. The undesirable effects of these actions are felt on-site, at the watershed level, and even nationally. Ecological cause-effect relationships are poorly understood, and few examples exist of the successful integration of ecological knowledge with upland development. It is hypothesized that recent results of ecological research could be applied to uplands management so that stable sustainable systems of human use may be established. A second hypothesis is that statistically reliable data can be obtained from experiments in upland situations, although natural variations of soils, weather, and vegetation are great. To test these hypotheses, research involving multinational collaboration among American and Southeast Asian scientists has begun. The objective of the work is to provide credible quantitative information to help policy and decision makers and resident farmers to plan and implement improved practices based on ecological principles.Some findings to date include:
1.  Ecological principles are difficult to relate to the practical context of upland agroecosystems. Indeed, the null hypothesis is necessary for planning experiments and demonstrations.
2.  The signal-to-noise ratio in these field experiments is low, and the detection of changes due to human intervention in soil erosion, nutrient movement, and plant productivity is difficult.
3.  Obstacles to field research in developing countries include logistic, cultural, political, and institutional factors. It is essential that local land managers participate from the start with scientific researchers in designing experiments.
4.  Planned collaboration among academic and government scientists facilitates design of relevant research and the implementation of results.
5.  The idea of ecologically based management has been well received by researchers and government officials in Asia. There is little argument with the logic of the approach.
6.  Pressures for quick responses to urgent problems in the uplands conflict with the need for careful, long-term, statistically valid scientific research.
7.  Ecological principles are vaguely understood and poorly articulated in the scientific literature. The transfer and application of ecological science to the developing world would be enhanced by clearer statements of principles.
  相似文献   

18.
In the past few decades, solid waste management systems in Europe have involved complex and multi-faceted trade-offs among a plethora of technological alternatives, economic instruments, and regulatory frameworks. These changes resulted in various environmental, economic, social, and regulatory impacts in waste management practices which not only complicate regional policy analysis, but also reshape the paradigm of global sustainable development. Systems analysis, a discipline that harmonizes these integrated solid waste management strategies, has been uniquely providing interdisciplinary support for decision making in this area. Systems engineering models and system assessment tools, both of which enrich the analytical framework of waste management, were designed specifically to handle particular types of problems. Though how to smooth out the barriers toward achieving appropriate systems synthesis and integration of these models and tools to aid in the solid waste management schemes prevalent in European countries still remains somewhat uncertain. This paper conducts a thorough literature review of models and tools illuminating possible overlapped boundaries in waste management practices in European countries and encompassing the pros and cons of waste management practices in each member state of the European Union. Whereas the Southern European Union (EU) countries need to develop further measures to implement more integrated solid waste management and reach EU directives, the Central EU countries need models and tools with which to rationalize their technological choices and management strategies. Nevertheless, considering systems analysis models and tools in a synergistic way would certainly provide opportunities to develop better solid waste management strategies leading to conformity with current standards and foster future perspectives for both the waste management industry and government agencies in European Union.  相似文献   

19.
There has been a large increase in private sector participation (PSP) in the urban water supply and sanitation (WSS) sector in recent years. However, even with increased PSP, public authorities will still have to: ensure that the service providers do not use their market power to exploit customers; internalise public health and environmental externalities; provide mechanisms whereby water consumption is sustainable and allocated efficiently between alternative uses; and stand as a guarantor of a level of service provision that is consistent with a basic standard of living. While there is considerable literature addressing the first of these four issues, the latter three are rather less adequately addressed. Through a review of a number of case studies (Abidjan, Buenos Aires/Cordoba, Mexico City and Manila), this paper provides an overview of the issues involved and some of the mechanisms available to the authorities responsible for the regulation of the sector.  相似文献   

20.
The concern of this paper is a review of the urban environmental degradation and the current approach by the military (environmental task force) in solving the problem. It is based on the experience of a few states in Nigeria. The paper proposes a comprehensive urban planning approach which should be integrated with an awareness campaign.  相似文献   

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