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1.
This report summarizes the results of two studies of electricity supply for Europe (EU), the Middle East (ME) and North Africa (NA) up to the year 2050. It shows that a transition to competitive, secure and sustainable supply of electricity and water is possible using renewable energy sources, efficiency gains and fossil fuel backup for balancing power. A strong cooperation between the EU and MENA for the market introduction of renewable energy and the interconnection of the electricity grids by high-voltage direct-current transmission are keys to the success and survival of the whole region. However, the necessary measures will take at least two decades to become effective. Therefore, adequate policy and economic frameworks for their realization must be introduced immediately. The importance of sustainable energy for the security of freshwater supplies in MENA is also described.
Hans Müller-SteinhagenEmail:
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2.
ABSTRACT

As the space carrier of the construction of ecological civilization, land’s green and efficient utilization is an important guarantee for realizing national sustainable development. Based on traditional land evaluation, this paper scientifically defines the green land use, puts land as one of the production factors, and brings energy consumption, environmental pollution, etc. into the input-output system to measure the green land utilization efficiency of the urban construction land of Beijing-Tianjin-Hebei Urban Agglomeration from 2006 to 2016. The study shows that the overall efficiency variation of the urban agglomeration is related with the land and environment policies. Efficiency of 2016 is higher than that of 2006, and energy and environment are the principal factors affecting the green land use. The efficiency of each city is positively correlated with its economic development, negatively correlated with the construction land expansion. Efficiency gaps in different cities are expanding. There is positive correlation with overall weak space between cities, and the partial spatial agglomeration phenomenon appears. Therefore, the green land use efficiency could be improved by improving land utilization efficiency, coordinating economic growth of construction land utilization with environmental protection and taking feasible ways to transregional renovation of the stock ecological land utilization, etc.  相似文献   

3.
Nowadays, many countries are looking towards sustainability as a goal because our world has limited resources and serious environmental impacts. In the construction industry, the process of sustainable selection of structural material is considered one of the keys to achieve more sustainable construction. In this paper, the theories of decision making are utilised to develop an approach for evaluation and ranking the structural materials over their total life based on sustainability criteria using multi-attribute decision-making methods. One of them is Analytical Hierarchy Process which is utilised to build the problem hierarchical structure and assign weights of the predetermined sustainable factors. The other is Technique for Order Preference by Similarity to the Ideal Solution which is utilised to rank the structural materials within both each material life cycle phase and the complete material life cycle phases. The third is the concept of entropy by Shannon to evaluate the weight factor for each phase of material life cycle. The proposed approach presents an objective, systematic and comprehensive method for the sustainable ranking of materials that links between the structural element design and the sustainable selection of materials.  相似文献   

4.
Understanding the earth system requires that the two-way linkages between regions and the global system be well understood and predictable. Most studies of global change are undertaken thematically across limited disciplinary boundaries; few are attempted holistically across many disciplines within regions. The regional approach offers many advantages. Here a variety of linkages associated with the regions of Southern Africa, South Asia, East Asia and Southeast Asia are presented to illustrate the power of a regional approach to earth system science. Major findings include the extent to which long-range transport of aerosols and nutrients affect terrestrial and marine ecosystem functioning in and around southern Africa. Aerosol transport, and the development of a regional haze layer, over South Asia are shown to alter significantly the radiative forcing of change in the atmosphere over the region. Changes in land cover and use over East Asia over along period of time are shown to have affected the strength of the monsoon circulation significantly. Finally, rampant economic development and globalization in Southeast Asia are demonstrated to have been a significant driver of regional change. Electronic Publication  相似文献   

5.
6.
This paper outlines the advantages of integrated crop–livestock systems and unsolved problems that need to be studied further. The discussion is subdivided by ecozone with consideration of arid and dry semi-arid areas with extensive livestock management; moist semi-arid and semi-humid areas where integrated crop–livestock systems are common; and humid areas where swine and poultry often predominate. To maintain soil organic matter in all ecozones, efficient recovery and use of nutrients from animal manures, crop residues and green manures is essential. In extensive systems in dry zones, animals transport nutrients from grazing areas to cropland, while in moister regions that are more intensively farmed, the emphasis is on the efficiency of nutrient recovery. Specific research questions relating to the overall ecosystem, nutrient cycling, plants, and animals are posed.  相似文献   

7.
The relationship between human beings and forests has been important for the development of society. It is based on various productive, ecological, social and cultural functions of forests. The cultural functions, including the spiritual and symbolic role of forests, are often not addressed with the same attention as the other functions. The aim of this paper is to put a stronger emphasis on the fact that the acknowledgement of cultural bonds is needed in the discussion of sustainable development. Forest should not only be considered as a technical means to solve environmental and economic problems. To achieve a deeper understanding of the dependency of society on forests, it is necessary to recognise the role of forests in our consciousness of being human. Giving a historical overview about the cultural bonds between people and forests, the first part of the paper puts focus on non-productive aspects in human–forest relationships. Through history, forest values have changed and new functions have emerged. Industrialisation and urbanisation have contributed to an alienation from nature and weakened the connection of humans to forests. The consequences of these changes for the development of society and its environment are discussed in the second part of the paper. Finally, it is elaborated how the awareness of the cultural bonds can be strengthened in the population and especially in forest management; a management which should relate to cultural, emotional and aesthetical aspects, in addition to economic, ecological and social functions, and lead towards a sustainable relationship between forests and society.  相似文献   

8.
Snow cover in Spanish mountains is crucial for ensuring water availability in spring and summer months, for the success of winter tourism or for the maintenance of biodiversity in mountain ecosystems. A changing climate may affect the volume of snow cover even in high mountains, where weather conditions are usually favorable for snow accumulation. In this paper, we aim to investigate the evolution (1970–2007) of combined precipitation–temperature modes in the Spanish mountains, and the sensitivity of the snowpack to their occurrence. The climatic database “Spain02” and snow thickness data for Spanish mountains were used for this purpose. Results showed that the frequency of dry-warm and wet-warm days has increased over time in all mountain ranges, while the frequency of the “cold” modes has decreased. The thickness of the snowpack in the Pyrenees has also decreased and its evolution is negatively correlated with the frequency of dry-warm days, and positively correlated with the frequency of dry-cold and wet-cold days. This work constitutes the first approach that relates the evolution of climatic conditions favorable or unfavorable for snow accumulation and the evolution of the snowpack in Spanish mountains.  相似文献   

9.
In order to analyze the factors influencing carbon emissions in the region of Beijing–Tianjin–Hebei and to explore the pathways to developing a low-carbon economy, this paper begins with the terminal energy consumption of three industries and residential consumption, and constructs an identical equation which is composed of population size, level of economic development, energy intensity, the proportion of energy consumption, energy structure, and the coefficient of carbon emissions. Based on the data of terminal energy consumption during 2000–2012, various factors are analyzed and their contribution is measured by Logarithmic Mean Divisia Index (LMDI). The results show that the levels of population and economy have a positive driving effect while energy intensity, energy structure, and carbon intensity have a negative driving effect; the proportion of energy consumption had a negative driving effect prior to 2006, then changed to positive. Among suggestions for a low-carbon economy are controlling population size, improving the quality of economic development, supporting research into new energy technology, accelerating regional integration and optimizing industrial structure, and enhancing environmental protection and spreading the concept of a low-carbon economy.  相似文献   

10.
Mullite-based glass-ceramics were produced from aluminium hydroxide sludge resulting from the anodisation process and waste glasses. Phase development for crystallisation of amorphous mullite was investigated between 900°C and 1200°C. The kinetic parameters such as activation energy of crystallisation and Avrami exponent for the samples were evaluated from differential thermal analysis curves using various heating rates (5–30°C) and particle size ranges ( < 45, 80–125 and 355–400 μm). The growth morphology parameters ‘n’ and ‘m’ are in the range of 2.5–5.4 and 1.5–4.4, respectively, indicating that bulk nucleation is dominant in mullite crystallisation followed by two- to three-dimensional growth of mullite crystals controlled by diffusion from a varying number of nuclei.  相似文献   

11.
采用Morlet小波分解重构和频谱分析等方法,对宜昌、枝城、沙市、监利和城陵矶1997~2014年水位和流量及三峡水库2003~2014年入库、出库流量和库水位数据进行了统计分析,探究了各水文站在三峡建坝前后水情的变化特征及原因。结果表明:各观测站的水位和流量沿程递减,水位的年内波动处同一水平,研究河段内上游河段流量年内和年际变化比下游河段剧烈;各水文站水位和流量变化的显著周期为6.05、11.78、21.2、30.29和53个月,各水文站水位1 a周期变化幅度均在2 m以上,其他周期上的变化幅度为0.08~0.82 m;三峡水库蓄水活动对下游水文站水位和流量等水情的影响有限,主要反映在对水情趋势项的影响上,三峡大坝蓄水后,各水文站水位和流量受到一定程度影响,呈波动性递减变化。  相似文献   

12.
Two U.S. long-term air quality indices, the National Air Quality Index, NAQI, and the Extreme Value Index, EVI, are calculated for 27 cities in Canada, for the period 1973 to 1976. The results indicate that air quality varies considerably in space and time and that no clear trends can be discerned. Total suspended particulate matter, ozone, and sulphur dioxide are the air pollutants most commonly found to exceed the air quality standards in the residential, commercial, and industrial areas of the 27 cities studied.  相似文献   

13.
Successful conservation efforts require understanding predictors of private-land stewardship (PLS), its definitions, and what people feel they owe stewardship responsibility to. Various strands of research have touched on the concept, but there is little research focusing on how it is communicated and enacted among the lay public, especially among Latinos. We used a case study in the Lower Rio Grande Valley of Texas to address this gap by identifying and assessing Latino views of PLS. Our results indicate positive relationships between self-identification as a land steward, male gender, and agricultural-land ownership. Respondents associated PLS with property maintenance (60%), natural-resource conservation (14%), and addressing pollution problems (21%). They viewed PLS as a responsibility owed to family rather than to a larger community.  相似文献   

14.
For over 20 years the radioactive noble gas 85Kr, the product of nuclear industry, has been released to the environment mainly from nuclear fuel reprocessing plants. Owing to its relatively long half-life T(12 = 10.76 y) and the absence of other appreciable sinks, a cumulative buildup of 85Kr in the atmosphere is observed. The mean 85Kr surface air activity in the northern hemisphere has increased from about 20 dpm/mmol Kr in 1950 to about 750 dpm/mmol Kr in 1977. In recent years, a substantial slow-down of the 85Kr emission rate to the atmosphere has been observed. The published data indicate rather good mixing of 85Kr in the northern hemisphere, but a gradient is observed in the southern hemisphere due to the fact that all nuclear fuel reprocessing plants are situated in the northern hemisphere and due to poor mixing of the atmosphere in the meridional direction.This paper summarizes nearly all of the data on 85Kr activity in the atmosphere published up to the middle of 1978. The spatio-temporal distribution of 85Kr atmospheric activity is discussed. Some forecasts of future 85Kr concentration in the atmosphere and its possible ecological consequences are also presented.  相似文献   

15.
The ozone distribution observed for April to September, 1976 and 1977, have been categorized and analyzed according to episodes. The major characteristics of the 40 ozone episodes are discussed. The major features are: (1) most episodes were associated with high pressure systems that enter the United States of America through Minnesota, (2) they normally have a duration which averages seven days for both years, (3) transported ozone from the midwest affected the northeastern United States and (4) the highest ozone concentrations were usually found in Connecticut. A particular episode, 9–19 May 1977, is examined in detail and shows the production of ozone in the midwestern United States under stagnant conditions and its eventual eastward transport. The first two days of the subsequent episode are shown to demonstrate the local accumulation of ozone in the northeast. The distribution of ozone throughout the entire eastern half of the country is also illustrated.  相似文献   

16.
Biomass fuels have attracted an increase in interest due to the alarming rise in global greenhouse gases and the rapid rise of petroleum prices. Energy security on a sustainable basis can come only with the responsible use of home-sourced resources and not from imported fossil fuels such as coal or crude petroleum products. Partial combustion of biomass in the downdraft gasifier generates producer gas that can be used as the sole fuel or as a supplementary fuel for internal combustion engines. A dual fuel mode of operation, in which producer gas is used as a supplementary inducted fuel along with injected pilot fuels of Honge or Jatropha biodiesels, can be a promising alternative to diesel only usage. Two different carburettors were designed and fabricated to facilitate gas entry at 45° and 90° to the engine cylinder. The engine was experimentally optimised using Honge or Jatropha biodiesels–producer gas combinations with respect to maximum pilot fuel savings in the dual fuel mode operation, optimum air and gas mixing with different tested carburettors. The performance, combustion and emission characteristics of these dual fuel combinations were compared at different load conditions. The results showed that biodiesels of Honge or Jatropha oils–Producer gas combinations with carburettor of 90° gas entry resulted in better performance.  相似文献   

17.
Abstract

In recent years, the concepts of sustainability and product service system have been closely associated with each other. In today’s competitive markets, due to Extended Producer Responsibility and customer environmental awareness, producers shift from ‘product-seller’ towards ‘product-service provider’ for using the environmental and economic advantages of coupling a product with services. This paper proposes a novel approach to determine the optimal warranty period and the out-of-warranty replacement period, from the point of view of the producer and the customer to minimise the total cost of usage and end of life of product. As regards the fact that adopted strategies by producers and customers sometimes are in conflict and it affects choosing the optimal product usage period, a game theory model was developed in this study. Finally, a case study with data from chain of local notebook service centres was applied to demonstrate some practical aspects of the developed model.  相似文献   

18.
Rural–urban land conversion is an inevitable phenome non in urbanization and industrialization. And the decision-making issue about this conversion is multiobjective because the socia decision maker (the whole of central government and local author ity) has to integrate the requirements of different interest groups (rural collective economic organizations, peasants, urban land us ers and the ones affected indirectly) and harmonize the sub-objects (economic, social and ecological outcomes) of this land alloc...  相似文献   

19.
This paper tries to identify the characters that might affect interprovincial migrants’ decisions and examine how and why the influence of these characters changed over time individually and synthetically in China during 1985–2005. We have investigated six types of factors, namely, distance, population density, income, employment structure, house price, and migration stock. In addition, we apply the identified factors with a multiple stepwise regression model to a longitudinal dataset, which consists of interprovincial migration flows over the last two decades in China. It is found that different factors have disparate impacts on migration in China, and they can be decomposed into push force in origin area and pull force in destination area. Factors shaping China’s interprovincial migration have shifted from traditional factors such as distance to economic factors such as income and employment structure. This paper suggests that more attention should be paid to obtain detailed migration data with spatial information and develop applicable models for migration processes. Our analysis provides references for development planners and policymakers to develop sound population policies to achieve regional sustainable development in China.  相似文献   

20.
Abstract

Rural–urban land conversion is an inevitable phenomenon in urbanization and industrialization. And the decision-making issue about this conversion is multi-objective because the social decision maker (the whole of central government and local authority) has to integrate the requirements of different interest groups (rural collective economic organizations, peasants, urban land users and the ones affected indirectly) and harmonize the sub-objects (economic, social and ecological outcomes) of this land allocation process. This paper established a multi-objective programming model for rural–urban land conversion decision-making and made some social welfare analysis correspondingly. Result shows that the general object of rural–urban land conversion decision-making is to reach the optimal level of social welfare in a certain state of resources allocation, while the preference of social decision makers and the value judgment of interest groups are two crucial factors which determine the realization of the rural–urban land conversion decision-making objects.  相似文献   

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