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1.
Environmental Science and Pollution Research - In this paper, a concept of balance is used to improve the important parameters of the thermal systems. In fact, using this concept give the designer...  相似文献   

2.
A brief report on the development of novel apparatus is presented. It was verified in a commercial scale that a new concept of anaerobic fermentation followed by continuous pyrolysis is technically and economically feasible to manage previously enzymatically hydrolyzed waste haylage in huge volumes. The design of the concept is thoroughly described, documented in figures, and biochemically analyzed in detail. Assessment of the concept shows that subsequent pyrolysis of the anaerobically fermented residue allows among biogas to produce also high-quality biochar. This significantly improves the overall economy. In addition, it may be assumed that this applied research is consistent with previous theoretical assumptions stating that any kind of aerobic or anaerobic fermentation increases the microporosity of the biochar obtained.  相似文献   

3.
First mooted in 2011, the concept of Trapped Populations referring to people unable to move from environmentally high-risk areas broadened the study of human responses to environmental change. While a seemingly straightforward concept, the underlying discourses around the reasons for being ‘trapped’, and the language describing the concept have profound influences on the way in which policy and practice approaches the needs of populations at risk from environmental stresses and shocks. In this article, we apply a Critical Discourse Analysis to the academic literature on the subject to reveal some of the assumptions implicit within discussing ‘trapped’ populations. The analysis reveals a dominant school of thought that assisted migration, relocation, and resettlement in the face of climate change are potentially effective adaptation strategies along a gradient of migrant agency and governance.  相似文献   

4.
The concept of sustainable development is steadily approaching recognition, if not full disciplinary autonomy, becoming the focus of new theoretical and normative reflection. However, the same cannot be said of a more specific field of application of that same concept - the urban environment. In our opinion, this has been hindered until recently by some unresolved problems - of definition, methodology and epistemology - intrinsic in the more general concept, and also by some specificities of the urban case that have not been sufficiently borne in mind. This paper aims at directly facing these unresolved problems, and proposes a definition on which later empirical studies and new theoretical elaborations may be based. A city is, by nature, a manufact, an almost entirely artificial object, constructed for historical goals of socialisation, synergy, increase of knowledge and social wellbeing. A 'weak' concept of sustainability, which permits ample substitutability between production inputs and utility function inputs, is almost impossible to avoid. When considering the problem in its entirety, we must combine the socio-cultural, economic and environmental elements, which all go towards the construction of that complex set of relations we call city. Sustainable urban development may be defined as a process of synergetic integration and co-evolution among the great subsystems making up a city (economic, social, physical and environmental), which guarantees the local population a non-decreasing level of wellbeing in the long term, without compromising the possibilities of development of surrounding areas and contributing by this towards reducing the harmful effects of development on the biosphere.  相似文献   

5.
Environmental Science and Pollution Research - The concept of this paper was to explore the comparative advantage of polymer composite in the formation of a critical part of electrodes, separators,...  相似文献   

6.
Defense and avoidance of ozone under global change   总被引:8,自引:0,他引:8  
The level II approach of the critical loads concept adopted by the UNECE aims at a flux based evaluation and takes into account environmental factors governing stomatal conductance. These factors will probably be affected by global change. The flux concept predicts that a decrease in stomatal conductance would protect trees from air pollution effects by decreasing uptake. However, experimental evidence is inconclusive. Numerous results suggest that pollutants and factors subject to global change (drought, CO(2)) may interact and even exacerbate effects, probably because antioxidative defense systems are involved in both, defense against pollutant effects and protection from natural stress. An effective pollutant dose, which is weighted by physiological defense capacity, would better predict such effects. In this review paper we argue that the flux-based approach is imperfect, because global change effects may also modify the physiological susceptibility to ozone. Instead, a flux concept weighted by defense capacity should be tested.  相似文献   

7.
本文从经济学角度分析了环境外部不经济的内涵、特点、解决途径及其发展方向。  相似文献   

8.
Guillaume Chapron 《Ambio》2015,44(4):550-556
Research in wildlife management increasingly relies on quantitative population models. However, a remaining challenge is to have end-users, who are often alienated by mathematics, benefiting from this research. I propose a new approach, ‘wildlife in the cloud,’ to enable active learning by practitioners from cloud-based ecological models whose complexity remains invisible to the user. I argue that this concept carries the potential to overcome limitations of desktop-based software and allows new understandings of human-wildlife systems. This concept is illustrated by presenting an online decision-support tool for moose management in areas with predators in Sweden. The tool takes the form of a user-friendly cloud-app through which users can compare the effects of alternative management decisions, and may feed into adjustment of their hunting strategy. I explain how the dynamic nature of cloud-apps opens the door to different ways of learning, informed by ecological models that can benefit both users and researchers.  相似文献   

9.
利用植物修复污染土壤研究进展   总被引:1,自引:0,他引:1  
本文介绍了植物修复技术的概念及其内涵,回顾了植物修复技术的研究历史,对该项技术的国内外研究现状与未来发展方向进行了讨论。同时指出,植物修复技术优点与其局限性。文中还对利用植物修复重金属污染的土壤应该考虑的因素作了简单的讨论  相似文献   

10.
- DOI: http://dx.doi.org/10.1065/espr2006.01.003 Background Water Quality Criteria were firstly defined in the 1970s by the EPA in the USA and the EIFAC in Europe, recognizing the need for protecting water quality in order to allow the use of water resources by man. In the 1990s, the European Commission emphasized the importance of safeguarding structure and function of biologic communities. These approaches were chemically-based. The European Water Framework Directive (WFD) substantially changes the concept of Water Quality, by assuming that a water body needs to be protected as an environmental good and not as a resource to be exploited. In this frame, the biological-ecological quality assumes a prevailing role. Main Features The Water Quality concept introduced by the WFD is a challenge for environmental sciences. Reference conditions should be defined for different typologies of water bodies and for different European ecoregions. Suitable indicators should be developed in order to quantify ecological status and to define what a 'good' ecological status is. Procedures should be developed for correlating the deviation from a good ecological to the effects of multiple stressors on function and structure of the ecosystem. The protection of biodiversity becomes a key objective. In this frame, the traditional procedures for ecotoxicological risk assessment, mainly based on laboratory testing, should be overcome by more site-specific approaches, taking into account the characteristics and the homeostatic capabilities of natural communities. In the paper an overview of the present knowledge and of the new trends in ecotoxicology to get these objectives will be given. A procedure is suggested based on the concept of Species Sensitivity Distribution (SSD). Recommendations and Perspective . The need for more site-specific and ecologically-oriented approaches in ecotoxicology is strongly recommended. The development of new tools for implementing the concept of 'Stress Ecology' has been recently proposed by van Straalen (2003). In the same time, more 'cological realism'is needed in practically applicable procedures for regulatory purposes.  相似文献   

11.
阐述了资源循环型农业的基本概念及其特征,根据循环经济的相关理论和国内外农业发展的实际情况,指出中国农业应在生态农业的基础上,朝着资源循环型农业的目标发展。  相似文献   

12.
Technical developments have now made it possible to emplace granular zero-valent iron (Fe(0)) in fractured media to create a Fe(0) fracture reactive barrier (Fe(0) FRB) for the treatment of contaminated groundwater. To evaluate this concept, we conducted a laboratory experiment in which trichloroethylene (TCE) contaminated water was flushed through a single uniform fracture created between two sandstone blocks. This fracture was partly filled with what was intended to be a uniform thickness of iron. Partial treatment of TCE by iron demonstrated that the concept of a Fe(0) FRB is practical, but was less than anticipated for an iron layer of uniform thickness. When the experiment was disassembled, evidence of discrete channelised flow was noted and attributed to imperfect placement of the iron. To evaluate the effect of the channel flow, an explicit Channel Model was developed that simplifies this complex flow regime into a conceptualised set of uniform and parallel channels. The mathematical representation of this conceptualisation directly accounts for (i) flow channels and immobile fluid arising from the non-uniform iron placement, (ii) mass transfer from the open fracture to iron and immobile fluid regions, and (iii) degradation in the iron regions. A favourable comparison between laboratory data and the results from the developed mathematical model suggests that the model is capable of representing TCE degradation in fractures with non-uniform iron placement. In order to apply this Channel Model concept to a Fe(0) FRB system, a simplified, or implicit, Lumped Channel Model was developed where the physical and chemical processes in the iron layer and immobile fluid regions are captured by a first-order lumped rate parameter. The performance of this Lumped Channel Model was compared to laboratory data, and benchmarked against the Channel Model. The advantages of the Lumped Channel Model are that the degradation of TCE in the system is represented by a first-order parameter that can be used directly in readily available numerical simulators.  相似文献   

13.
A new vegetation modeling concept for Building and Environmental Aerodynamics wind tunnel investigations was developed. The modeling concept is based on fluid dynamical similarity aspects and allows the small-scale modeling of various kinds of vegetation, e.g. field crops, shrubs, hedges, single trees and forest stands. The applicability of the modeling concept was validated in wind tunnel pollutant dispersion studies. Avenue trees in urban street canyons were modeled and their implications on traffic pollutant dispersion were investigated. The dispersion experiments proved the modeling concept to be practicable for wind tunnel studies and suggested to provide reliable concentration results. Unfavorable effects of trees on pollutant dispersion and natural ventilation in street canyons were revealed. Increased traffic pollutant concentrations were found in comparison to the tree-free reference case.  相似文献   

14.
Contaminated industrial sites are important sources of pollution and may result in ecotoxicological effects on terrestrial, aquatic and groundwater ecosystems. An effect-based approach to evaluate and assess pollution-induced degradation due to contaminated groundwater was carried out in this study. The new concept, referred to as “Groundwater Quality TRIAD-like” (GwQT) approach, is adapted from classical TRIAD approaches. GwQT is based on measurements of chemical concentrations, laboratory toxicity tests and physico-chemical analyses. These components are combined in the GwQT using qualitative and quantitative (using zero to one subindices) integration approaches. The TRIAD approach is applied for the first time on groundwater from one former industrial site located in Belgium. This approach will allow the classification of sites into categories according to the degree of contaminant-induced degradation. This new concept is a starting point for groundwater characterization and is open for improvement and adjustment.  相似文献   

15.
有机化合物动态定量结构——生物降解关系(QSBR)模型研究   总被引:1,自引:0,他引:1  
本文通过分析一般QSBR模型应用的特点、不足和影响有机物生物降解的基本因素,指出QSBR模型应综合反映影响有机物生物降解的四个方面(以氯代芳香化合物为例):氯代苯系物的摄入、氯代苯系物的诱导作用、毒性物质的形成和基础酶的缺乏。在此基础之上给出了动态QSBR的概念模式及方法学基础。  相似文献   

16.
景观影响评价中"景观"的内涵和应用探讨   总被引:1,自引:0,他引:1  
陈力 《环境污染与防治》2004,26(2):148-150,153
针对目前不同学科对于景观概念存在多种不同的解释,文章对环境影响评价中所基于的景观概念的内涵进行了探讨,指出了景观科学具有边缘性和开放性的特点。并根据目前中国景观影响评价的实际情况,提出了一些建议。  相似文献   

17.
中国有机食品的研究与发展前景   总被引:3,自引:0,他引:3  
介绍了有机食品的基本概念和有机食品所应具备的条件,并比较了有机食品与绿色食品的区别与联系;在对国内外有机食品的发展概况和中国发展有机食品的有利条件的全面论述和分析的基础上,阐明了中国有机食品的发展不仅有着良好的国内外市场,而且有着广阔的前景。  相似文献   

18.
Over the past several years, the Environmental Protection Agency has attempted to institutionalize an approach to its activities that is characterized by an active attempt to separate risk assessment from risk management activities. This approach, while not new in concept, has only been evolving at EPA for about four years. The Office of Research and Development, or ORD, has organized its research planning activities around this risk assessment-risk management concept. In order for the approach to succeed, it is necessary to develop the data and methodology necessary to undertake risk assessments both in the area of human health and ecology, and to develop methods to reduce those risks. Accordingly, we have organized our research planning into four major areas: Human Health Risk, Environmental or Ecological Risk, Exposure Assessment, and Risk Reduction. What I would like to do is outline briefly the breadth and diversity of EPA’s research program and the Agency’s research needs.  相似文献   

19.
The Biosphere Reserve (BR) concept aims at encouraging sustainable development (SD) towards sustainability on the ground by promoting three core functions: conservation, development, and logistic support. Sweden and Ukraine exemplify the diverse governance contexts that BRs need to cope with. We assessed how the BR concept and its core functions are captured in national legislations. The results show that the core functions are in different ways reflected in legal documents in both countries. While in Ukraine the BR concept is incorporated into legislation, in Sweden the concept is used as a soft law. In Ukraine managers desired stronger legal enforcement, while in Sweden managers avoided emphasis on legislation when collaborating with local stakeholders. Hence, BR implementation have adapted to different political cultures by development of diverse approaches. We conclude that a stronger legal support might not be needed for BRs, rather SD needs to be recognized as an integrated place-based process at multiple levels.  相似文献   

20.
房地产开发建设项目环境影响评价的新问题探讨   总被引:1,自引:0,他引:1  
对房地产开发建设项目环境影响评价中出现的新问题进行了识别与分析,提出了需要将建筑节能、室内环境质量影响评价引入建设项目环境影响评价的基本内容,并针对绿色概念的实施机制进行了探讨。讨论了房地产开发建设项目环境影响评价中需要重视的内容。  相似文献   

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