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991.
Addressing urban housing crisis is an enormous challenge for most of the countries due to the increasing cost of the building material. Therefore, affordable alternative building material can make a breakthrough to the urban housing crisis. In the light of current success of stabilised earth construction in urban low-cost housing, it is important to find out the potential drivers that can help to adopt this building material. This paper aims to identify and highlight these drivers from the method of literature review and validates through a Delphi technique.  相似文献   
992.
The developing countries i.e., the non-Annex-I countries (parties to the Kyoto Protocol but not responsible to any reduction target yet) in the Kyoto Protocol whose economies are in transition are also allowed to reduce GHG emissions. Among these, the countries that have accepted the Kyoto Protocol may be benefited from CDM projects to promote sustainable development. The developed countries i.e., the Annex-I countries (that have signed the Kyoto Protocol & are responsible to have specific GHG emission reduction target) or the investing countries, in return, have privilege to purchase CER credits (in units equivalent to one tonne of CO2 gas emission reduction) to meet the emission target as specified in the Kyoto Protocol. The key step in understanding about CDM is to grasp the concept of “baseline” and “additionality”. The “Baseline” is the emissions level that would have existed if a CDM project had not happened. The feature of an approved CDM project is that the planned reductions would not occur without the additional incentive provided by emission reduction credits; this concept is known as “Additionality”. According to environmental additionality concept, baseline emission minus project emission is equal to emissions reduction. “Investment Additionality,” ultimately rejected during negotiation of the “Marrakech Accords” and “Financial Additionality,” are the two important concepts. The concept of trading of CER matches to the idea of Pigovian tax (equal to the negative externality and which is considered one of the “traditional” means of bringing a modicum of market forces) in Economics, making pollution more costly to the polluter, as the polluters have negative cost since they save money by polluting; hence, there are supposed negative externalities associated with the market activity. Economic theory predicts that in an economy where the cost of reaching mutual agreement between parties is high and where pollution is diffuse, Pigovian tax will be an efficient way to promote the public interest and will lead to an improvement of the quality of life measured by the Genuine Progress Indicator and other human economic indicators, as well as higher gross domestic product growth. We can seek a level of pollution such that the marginal savings (MS) to one polluting unit from pollution (−MC) is equal to marginal damage (MD) from pollution over the entire population, since pollution is a public bad i.e., MS (x*) = ∑MDi (x*) where ∑Di (x) is the total damage. Though the responsibility of reduction in emission does not lie on the non-Annex-I countries, still effort of maintaining global emission balance can be expected equally from developed and developing countries. The responsibilities of Kyoto Protocol are (a) to reduce global GHG emissions, (b) to bring about sustainable development in the developing countries lie on above two groups since its effect on February 16, 2005. Different polluters have different costs of pollution control. The least costly way of controlling pollution from various sources that reflects different costs of pollution control making the set of environmental regulations to achieve the emission target at the lowest cost makes the regulation cost-effective. Though efficiency is not attainable for many regulations, cost-effectiveness is attainable.  相似文献   
993.
994.
Sub-Saharan Africa has been portrayed as the most vulnerable region to the impacts of global climate change because of its reliance on agriculture which is highly sensitive to weather and climate variables such as temperature, precipitation, and light and extreme events and low capacity for adaptation. This article reviews evidence on the scope and nature of the climate change challenge; and assesses the impact of climate change on agriculture and food security in Sub-Saharan Africa. From the review, it is apparent that the climate in Africa is already exhibiting significant changes, evident by changes in average temperature, change in amount of rainfall and patterns and the prevalence of frequency and intensity of weather extremes. The review also revealed that although uncertainties exist with regards to the magnitude of impacts, climate will negatively affect agricultural production in Sub-Saharan Africa. Specifically, as result of current and expected climate change, the area suitable for agriculture, the length of growing seasons and yield potential, particularly along the margins of semi-arid and arid areas, are expected to decrease. These impacts will affect all components of food security: food availability, food accessibility, food utilisation and food stability and hence increase the risk of hunger in the region. The review thus confirms the general consensus that Sub-Saharan Africa is the most vulnerable region to climate change. It suggests that, policymakers and development agencies should focus on formulating and implementing policies and programmes that promote farm level adaptation strategies currently being practiced by farmers across the region.  相似文献   
995.
The Arctic is a region of the world experiencing extremely rapid climatic and social change. Indigenous communities have faced similar challenges for millennia and have historically demonstrated remarkable resilience to socioecological perturbations. In contemporary contexts, however, it appears that the pace and extent of change is overwhelming the adaptive capacities of many indigenous communities. Scholars recently completed a survey of living conditions spanning the circumpolar Arctic to quantitatively document the impacts of social and ecological stress across regions. The database they created is called the Survey of Living Conditions in the Arctic or SLiCA. This article explores the utility of using this dataset to compare livelihood systems across three sub-regions of Alaska and four sub-regions within the Chukotka Autonomous Okrug of the Russian Federation. The results point out that livelihood systems in Chukotka have a substantially lower level of sustainability than in Northwest Alaska due to the high prevalence of vulnerable households.  相似文献   
996.
This study aims to estimate the intensification of rice farming in Myanmar particularly due to chemical fertilizer application, using farm-level data obtained from field surveys conducted in the 2000s. Relatively high-input rice farming was found in dry season crop in the delta zone and the double crop in well-irrigated lowlands of the central dry zone. The chemical fertilizer used there was about 88–159 kg NPK (nitrogen, N; phosphate, P2O5; and potash, K2O) ha−1 (76–110 kg nitrogen (N) ha−1), and the average paddy yield ranged from 2.8 to 3.5 ton ha−1. On the other hand, nutrient input in survey sites of rain-fed lowland was between 11 and 53 kg NPK ha−1 (5 and 36 kg N ha−1), and the yield ranged from 1.1 to 2.3 ton ha−1. The national average of paddy yield and nutrient input of fertilizer was roughly estimated to be around 2.4 ton ha−1 and 60 kg NPK ha−1, respectively. A gap was observed between these calculated values and the official statistics. A comparison of fertilizer use efficiency for rice production in Myanmar with that in China and Vietnam has shown that the efficiency in Myanmar has not declined to an inappropriate level even in its intensive ones. Rice production in Myanmar has room for increasing the yield by capital intensification. Nevertheless, considering its sustainability as well as productivity, further intensification in rice farming technology in irrigated lowlands of Myanmar may neither be the best nor the only way.  相似文献   
997.
Renewable energy sources are mainly used in the electrical sector. Electricity is not a storable commodity. Hence, it is necessary to produce the requested quantity and distribute it through the system in such a way as to ensure that electricity supply and demand are always evenly balanced. This constraint is actually the main problem related to the penetration of new renewables (wind and photovoltaic power) in the context of complex energy systems. The paper analyzes some aspects in connection with the problem of new renewable energy penetration. The case of Italian scenario is considered as a meaningful reference due to the characteristic size and the complexity of the same. The various energy scenarios are evaluated with the aid of a multipurpose software taking into account the interconnections between the different energetic uses. In particular, it is shown how the penetration of new renewable energies is limited at an upper level by technological considerations and it will be more sustainable if an integration of the various energy use (thermal, mobility and electrical) field will be considered.  相似文献   
998.
As an economically developing country, Turkey has very well operated integrated solid waste management applications structured on modern facilities, besides over 2,000 scattered open dump areas in the country. Integrated waste management applications seem eligible for the metropolitan cities like Istanbul and Izmit (Kocaeli). Attempts have not been encouraging for the scattered regional settlements using central storage sites due to financial shortages and received rejections from nearby settlements. Small-scale compact solid waste management systems with materials recycling and composting can be more suitable alternatives in the small-scale regional settlements. The major constituents of municipal solid waste are organic in nature and approximately a quarter of municipal solid waste is recyclable. Although paper, including cardboard, is the main constituent, the composition of recyclable waste varies strongly by the source or the type of collection point. Solid wastes need primary treatment in order to be suitable for incineration and composting. Turkey needs to give more emphasis on the usage of modern solid waste removal technologies to overcome the overgrowing solid waste disposal problems.  相似文献   
999.
The circular economy has been developing rapidly in recent years in China. A legislative system has been created to provide legal protection for the development of a circular economy, including a series of price and tax measures in the waste management area. These measures form the basic foundation for promoting better waste management under the circular economic model. Many challenges, however, remain. For instance, the legal system needs to incorporate more sophisticated science, and China lacks key waste treatment technology that could support the further development of a circular economy. There is also a need to educate the public about the concept of the circular economy and its benefits. Specific suggestions are made for the development and implementation of the circular economic model.  相似文献   
1000.
Since hydrogen is a renewable energy source, biohydrogen has been researched in recent years. However, data on hydrogen fermentation by a leachate from a waste landfill as inoculum are scarce. We investigated hydrogen production using a leachate from an industrial waste landfill in Kanagawa Prefecture. The results showed no methane gas production, and the leachate was a suitable inoculum for hydrogen fermentation. The maximum H2 yield was 2.67 mol of H2 per mol of carbohydrate added, obtained at 30°C and an initial pH of 7. The acetate and butyrate production was significant when the H2 yield was higher. Oxidation–reduction potential analysis of the culture suggested that hydrogen-producing bacteria in the leachate were facultative anaerobic. Scanning electron microscope observations revealed that the hydrogen-producing bacteria comprised bacilli about 2 μm in length.  相似文献   
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