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1.
The Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, was set up in Oct. 1986. It was composed of the former Institute of Environmental Chemi-stry, which was founded in 1975, and the Ecology Center. The purpose of setting up the Research Center for Eco-Environmental Sciences is to promote the cooperation of environmen- tal chemists, ecologists and geoscientists so as to solve ecological and environmental issues at regional, national and global levels through interdisciplinary studies.  相似文献   

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Homing pigeons are well known as good homers, and the knowledge of principal parameters determining their homing behaviour and the neurological basis for this have been elucidated in the last decades. Several orientation mechanisms and parameters—sun compass, earth’s magnetic field, olfactory cues, visual cues—are known to be involved in homing behaviour, whereas there are still controversial discussions about their detailed function and their importance. This paper attempts to review and summarise the present knowledge about pigeon homing by describing the known orientation mechanisms and factors, including their pros and cons. Additionally, behavioural features like motivation, experience, and track preferences are discussed. All behaviour has its origin in the brain and the neuronal basis of homing and the neuroanatomical particularities of homing pigeons are a main topic of this review. Homing pigeons have larger brains in comparison to other non-homing pigeon breeds and particularly show increased size of the hippocampus. This underlines our hypothesis that there is a relationship between hippocampus size and spatial ability. The role of the hippocampus in homing and its plasticity in response to navigational experience are discussed in support of this hypothesis.  相似文献   

4.
Algal-bloom control is an important issue for water environment protection as it induces several negative impacts on the lives of aquatic organisms, aquaculture, landscaping, and human health. The development of an environment-friendly, cost-effective, and convenient alternative for controlling algal bloom has gained much concern. Using the allelopathy of aquatic macrophytes as a novel and safe method for algal-bloom control is a promising alternative. This paper reviews the development and potential application about allelopathy of aquatic plants on algae, including the allelopathic research history, the potential research problems, the research methodology, and the reported aquatic macrophytes and their inhibitory allelochemicals. Potential modes of inhibition action of allelochemicals on algae, possible ways for application, and future development directions of research on algal-bloom control by aquatic macrophytes were also presented.  相似文献   

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Concerns over exposure to mercury have motivated the exploration of cost-effective, rapid, and reliable method for monitoring Hg2 + in the environment. Recently, surface-enhanced Raman scattering (SERS) has become a promising alternative method for Hg2 + analysis. SERS is a spectroscopic technique which combines modern laser spectroscopy with the optical properties of nano-sized noble metal structures, resulting in substantially increased Raman signals. When Hg2 + is in a close contact with metallic nanostructures, the SERS effect provides unique structural information together with ultrasensitive detection limits. This review introduces the principles and contemporary approaches of SERS-based Hg2 + detection. In addition, the perspective and challenges are briefly discussed.  相似文献   

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Ecosystem service(ES) trade-offs have been broadly recognized and studied over the past decade. However, how to coordinate the relationships among ES trade-offs to achieve win–win outcomes remains a considerable challenge for decision makers. Here, we summarize the current approaches applied to minimize ES trade-offs for win–wins and analyze the trade-offs among different ESs and their drivers. Based on a systematic review of the literature from 2005 to 2018, we identified 170 potentially relevant articles, 47 of which were selected for the review,recording 70 actual or potential trade-offs. Analysis of these case studies showed that trade-off pairs between provisioning services and regulating services/biodiversity accounted for 80% of total pairs. Furthermore, more than half of the ES trade-offs were driven by land use/land cover changes. Harvest and resource demand, natural resource management, and policy instruments were also among the main drivers. Four approaches to coordinate ES trade-offs were identified, including ecosystem, landscape-scale, multi-objective optimization, and policy intervention(and other) approaches. Based on the above, we recommend a rigorous understanding of the roles of different stakeholders, spatial scales of management, trade-off dynamics, and integrated implementation of diverse approaches to coordinate ES trade-offs in order to better achieve win–win outcomes.  相似文献   

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The rapid developments in all kinds of new information technologies, information networks and social media are increasingly affecting societies around the world. The so termed Information Age not only influences social relationships, economy and science, but also governance. Against this background and in the specific field of sustainability, informational governance is an emerging concept. It addresses two interrelated processes: (1) new forms of governing through information, and (2) transformative changes in governance institutions due to the new information flows. The aim of this article is to gain more insights into ways in which the Information Age impacts sustainability, and to suggest a research agenda with relevance to the field of informational governance. A systematic literature review resulted in a selection of 39 articles, of which 23 and 16 articles were identified in two-parallel searches. The increased human interconnectedness through e-governance, self-organization, private governing and empowerments are identified as core informational governance trends dealing with sustainability in the Information Age, and essential to future research.  相似文献   

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Flood damages have exhibited a rapid upward trend, both globally and in Europe, faster than population and economic growth. Hence, vigorous attempts of attribution of changes have been made. Flood risk and vulnerability tend to change over many areas, due to a range of climatic and nonclimatic impacts whose relative importance is site-specific. Flooding is a complex phenomenon and there are several generating mechanisms, among others intense and/or long-lasting precipitation, snowmelt, ice jam. Projected climate-driven changes in future flood frequency are complex, depending on the generating mechanism, e.g., increasing flood magnitudes where floods result of heavy rainfall and possibly decreasing magnitudes where floods are generated by spring snowmelt. Climate change is likely to cause an increase of the risk of riverine flooding across much of Europe. Projections of flood hazard in Europe based on climatic and hydrological models, reviewed in this paper, illustrate possible changes of recurrence of a 100-year flood (with probability of exceedance being 1-in-100 years) in Europe. What used to be a 100-year flood in the control period is projected to become either more frequent or less frequent in the future time horizon of concern. For a large part of the continent, large flooding is projected to become more commonplace in future, warmer climate. Due to the large uncertainty of climate projections, it is currently not possible to devise a scientifically-sound procedure for redefining design floods (e.g. 100-year flood) in order to adjust flood defenses. For the time being, we recommend to adjust design floods using a “climate change factor” approach.  相似文献   

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Constructed wetlands for wastewater treatment in cold climate — A review   总被引:2,自引:0,他引:2  
Constructed wetlands (CWs) have been successfully used for treating various wastewaters for decades and have been identified as a sustainable wastewater management option worldwide. However, the application of CW for wastewater treatment in frigid climate presents special challenges. Wetland treatment of wastewater relies largely on biological processes, and reliable treatment is often a function of climate conditions. To date, the rate of adoption of wetland technology for wastewater treatment in cold regions has been slow and there are relatively few published reports on CW applications in cold climate. This paper therefore highlights the practice and applications of treatment wetlands in cold climate. A comprehensive review of the effectiveness of contaminant removal in different wetland systems including: (1) free water surface (FWS) CWs; (2) subsurface flow (SSF) CWs;and (3) hybrid wetland systems, is presented. The emphasis of this review is also placed on the influence of cold weather conditions on the removal efficacies of different contami-nants. The strategies of wetland design and operation for performance intensification, such as the presence of plant, operational mode, effluent recirculation, artificial aeration and in-series design, which are crucial to achieve the sustainable treatment performance in cold climate, are also discussed. This study is conducive to further research for the understanding of CW design and treatment performance in cold climate.  相似文献   

11.
The progress of catalytic technologies in water purification: A review   总被引:4,自引:0,他引:4  
Catalytic technologies have been paid increasing attention in refractory pollutants abatement due to its practical and potential values in water purification. As e ective and e cient approaches for water purification, Fenton’s reagent, ozonation, electrochemical and photocatalytic methods have been widely studied and applied in di erent aspects and have been reviewed by several articles. In recent years, some novel catalytic processes based on above processes have been developed for enhancing the e ciency of removing the organics from water. This review emphasized on the recent development of heterogeneous catalytic ozonation, electrocatalysis in respect of novel electrodes and electro-Fenton method, photoelectrocatalysis process and photoelectron-Fenton in water purification. It was also an attempt to propose general ideas about mechanism and principle enhancing the catalytic e ciency for the degradation and the mineralization of organics in water.  相似文献   

12.
Application potential of carbon nanotubes in water treatment:A review   总被引:2,自引:0,他引:2  
Water treatment is the key to coping with the conflict between people’s increasing demand for water and the world-wide water shortage. Owing to their unique and tunable structural, physical, and chemical properties, carbon nanotubes (CNTs) have exhibited great potentials in water treatment. This review makes an attempt to provide an overview of potential solutions to various environmental challenges by using CNTs as adsorbents, catalysts or catalyst support, membranes, and electrodes. The merits of incorporating CNT to conventional water-treatment material are emphasized, and the remaining challenges are discussed.  相似文献   

13.
Plant materials which are available from farming regions in the moderate Austrian climate were investigated to serve as sources for natural dyes in textile dyeing operations. The extraction of the dye components from the plant materials was performed with boiling water without addition of chemicals or solvents. Based upon a rigorous selection of possible plant sources, a selection of natural dyestuffs applicable in a one-bath dyeing step was established. A broad variation in shade and color depth can be achieved by applying mixtures of natural dyestuffs in various combinations of iron- and alum-mordants. More than 60% of tested dyeings achieved acceptable fastness properties.On the basis of the developed natural dyestuff-based dyeing procedures, a comparison was made between the effluents from processes based upon them and those based upon the current ‘state-of-the-art’ techniques utilizing synthetic dyes. The comparison revealed that a lowering of the chemical load released with waste water can be expected by shifting to the plant-based dyes.  相似文献   

14.
Origin of 3He in the Earth is a mystery. Lacking a production mechanism, scientists assume 3He was trapped in the Earth, when the Earth was formed. In contrast to this assumption, we have found 3He and 3H concentrations in excess of the atmospheric values in the deep waters of the volcanic Lakes Pavin (France), Laacher (Germany) and Nemrut (Turkey). This paper reports the result of finding 3H in these three volcanic lakes that appear to originate from the mantle. Because 3H has a half-life of 12.3 years, this 3H and the resulting 3He must have formed recently in the mantle and not be part of a primordial reservoir. The nuclear reactions that generate tritium might be a source of “missing” energy in the interior of the Earth.  相似文献   

15.
Contributions from three urban sources of PAHs: domestic heating, petrol vehicles and diesel vehicles, were evaluated for various times of year and various times of day. Contributions were calculated by chemical mass balance from histograms of six PAHs that are present in the atmosphere only in particle form. The urban site studied (Paris, France) is an open site well suited to the use of a piston reactor model. This model has been modified to take into account the differences in reactivity between the particle PAHs and adapted to conserve its linearity. The correction is brought to bear upon the histograms from measurements taken at the receptor site, and leads to the construction of virtual profiles from which the contributions of the various sources are calculated.Evidence of seasonal and hourly variations is brought out. The results are very realistic and can be compared with information about vehicle traffic density and about energy consumption. They also show that the difference observed between summer and winter concentrations is mainly due to variations in production, and not to the decay of PAHs.  相似文献   

16.
The Industrial Pollution Control Association of Japan (IPCAJ) has carried out a 3-year study in order to promote an understanding of the behavior of suspended particulate matter, to identify the contributing sources and to estimate their contributions. In this study many monitoring stations were set up around the Kashima industrial area. Atmospheric aerosols were collected for 2 weeks in each of the four seasons of 1983. The chemical compositions of the aerosols were analysed by instrumental neutron activation analysis and so on.The results of the study showed that soil particles comprise the highest component, while sulfate and other secondary particles are higher in the spring ans summer. In the spring and fall when sea breezes are dominant, sea salt has been found to have a higher concentration, especially at sites near the shore.Following the above-mentioned information a source apportionment study was conducted using the chemical mass balance method. Results have shown that the contributions of soil and sea salt are greater than the contributions from industrial sources for the Kashima area.  相似文献   

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As an effective, efficient, and economic approach for water purification, adsorbents and adsorption processes have been widely studied and applied in different aspects for a long time. In the recent years, a lot of novel adsorption processes have been developed for enhancing the efficiency of removing the organic and inorganic contaminants from water. This article reviews some new adsorbents and advanced adsorption methods that specialize in their compositions, structures, functions, and characteristics used in water treatment. The review emphasizes adsorption/catalytic oxidation process, adsorption/catalytic reduction process, adsorption coupled with redox process, biomimetic sorbent and its sorption behaviors of POPs, and modified adsorbents and their water purification efficiency.  相似文献   

19.
A review: Advances in microbial remediation of trichloroethylene (TCE)   总被引:12,自引:0,他引:12  
Research works in the recent past have revealed three major biodegradation processes leading to the degradation of trichloroethylene. Reductive dechlorination is an anaerobic process in which chlorinated ethenes are used as electron acceptors. On the other hand, cometabolism requires oxygen for enzymatic degradation of chlorinated ethenes, which however yields no benefit for the bacteria involved. The third process is direct oxidation under aerobic conditions whereby chlorinated ethenes are directly used as...  相似文献   

20.
The origin of the pygmy right whale (Caperea marginata) has long been one of the most vexing conundrums of marine mammal evolution. The extremely disparate skeletal structure of Caperea and a patchy fossil record have left morphology and molecules at odds: whereas most morphological analyses ally Caperea with right whales (Balaenidae), most molecular studies instead suggest a close relationship with rorquals (Balaenopteridae) and grey whales (Eschrichtiidae). The morphological evidence supporting a Caperea-balaenid clade consists of several shared features of the skull and mandible, as traditionally observed in adult individuals. Here, we show that at least two of these features, the ascending process of the maxilla and the coronoid process, arise from substantially different precursors early during ontogeny and therefore likely do not represent genuine synapomorphies. Both of these juvenile morphologies have adult counterparts in the fossil record, thus indicating that the ontogenetic variation in the living species may be a genuine reflection of differing ancestral states. This new evidence contradicts previous morphological hypotheses on the origins of Caperea and may help to reconcile morphological and molecular evidence.  相似文献   

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