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1.
通过美国100年来SO2排放趋势分析, 对比日本、英国的相关数据资料, 发现SO2的排放与能源消费、经济发展、环境政策以及环保技术进步密切相关: 经济结构的转变和能源结构的调整是SO2减排的关键因素, 环保政策和技术进步是SO2减排的主要驱动力。典型国家SO2排放强度曲线均呈倒“U”型, 符合环境库兹涅茨曲线。SO2排放的拐点美国在人均GDP15000美元, 日本和英国在人均GDP9000～10000美元; 三个国家人均SO2排放强度的拐点在人均GDP5000～7000美元, 目前中国已经越过人均SO2排放的顶点。在此基础上本文提出了中国进一步减排SO2的建议。  相似文献   

2.
论述了最近５０年来世界矿产资源供求关系的变化和现状,着重讨论了独联体国家、北美地区西欧国家、中欧和东欧国家、日本、澳大利亚和南非共和国、欧佩克国家的矿产资源情况。俄罗斯仍是矿产资源大国,但矿山开采工业每况愈下,许多矿种没有清楚的探明储量。独联体一些国家某些矿种储量大,但没有维持经济正常发展的其它矿种。美国的某些矿种储量大,但其它矿种不足,例如石油、天然气、煤、铝、铜、铅、锌、锡、镍、钴、钨等需求量  相似文献   

3.
This study uses the bibliometric method to analyze the comparative studies on different market mechanisms applied to carbon reduction between 1970 and 2016 based on the online databases of Science Citation Index Expanded (1970–2016) and Social Science Citation Index (2002–2016). We found by observing the characteristics of publications that such studies belong to a multidisciplinary field that has been continuously developing since the 1990s. The USA and the UK have maintained their leading research strengths in the field, whereas China entered late but has developed rapidly. The most productive journal, institution, and author in this field are Energy Policy, Resources for the Future, and Pizer from the USA, respectively. The auctorial and institutional cooperation degrees are growing and still have a broad collaboration space, but the cooperation among countries is fluctuating at a lower level. Nonetheless, the USA keeps its significant international cooperation ties. The bibliographic coupling and co-citation analysis reveals that articles in this field are closely related to one another. The basic literature in the field was written by Weitzman and published in 1974, and the article by Nordhaus published in Science in 1992 is the most cited in the field. The analysis of keywords and abstract shows that the hot spots include policy choice, price-versus-quantity analysis, and mechanism design.  相似文献   

4.
Water resources issue is affecting regional stability and national relationship, which has become a vital issue. Based on SCIE papers from database of Web of Science, we analyze the international development trend of water governance research using the bibliometric analysis method. The results show that the number of publications in this field has been increasing rapidly since the 1990s. Most of the research subjects are interdisciplinary and mainly focus on the field of water resources and environmental science. Base on publications and its cited, the United States has the absolute advantage in total numbers of papers, but the articles has a low average influence in terms of citations; The total number of papers in China on water governance research ranks 10th among major countries in the world, but all papers in this field are cited, ranking second only to Germany. International water governance research focuses on water resource acquisition and water quality assessment, water vulnerability, adaptation and water demanding related to climate change; decision-making, water governance policies and water rights; water resource management, such as groundwater management, watershed management and comprehensive water resources management; global water governance and urban water crisis.  相似文献   

5.
The Arab world’s environment is among the most vulnerable and harsh ones across the globe. This entails much efforts to mitigate the potential environmental risks. Analysing contributions of Arab scholars in environmental research in terms of quantity and quality can bring up insights on their endeavours in this regard. Bibliometric techniques are proposed to conduct such this analysis over publications originated from Arab world in a leading environmental journal “Science of the Total Environment”. Research productivity is being used as quantitative indicator, while citation rates and Hirsch index (h-index) are being used as qualitative indicators. The research outputs were compared with those obtained from non-Arab Middle Eastern countries (Iran, Turkey and Israel). Worldwide research productivity was 17,258 documents, while that from Arab countries, Iran, Turkey and Israel were 215, 34, 83 and 87 documents, respectively. The h-index of Arab world research was 31, and total citations were 3616 with an average of 16.8. The highest share of publications was recorded by Saudi Arabia (53 documents; 24.7%). Egypt and Saudi Arabia had highest h-index with 15 for each one. American University of Beirut in Lebanon was the highest productive institution (16; 7.4%). The most collaborated country with Arab world was France (29; 13.5%). In the conclusion, the study reveals a clear gap in terms of research productivity between Arab countries and other Middle Eastern countries, precisely Israel and Turkey. More research efforts through optimizing investments in environmental research, developing regional experiences and fostering international collaboration are required to eliminate these lags.  相似文献   

6.
Extreme climatic events are likely to adversely affect many countries throughout the world, but the degrees among countries may be different. China and Japan are the countries with high incidences of extreme weather/disaster, both facing with the urgent task of addressing climate change. This study seeks to quantitatively compare the impacts of extreme climatic events on socioeconomic systems (defined as vulnerability) of the two countries by simulating the consequences of hypothetical same degree of electricity disruption along with extreme events. To do that, two computable general equilibrium models are constructed, by using which three-stage scenarios are simulated for China and Japan, respectively. The results reveal that China and Japan have unequal socioeconomic vulnerabilities to extreme events. (1) Negative impact of the same degree of power outages is bigger on China’s socioeconomic system than on that of Japan, and this difference is more obvious in the very short-run scenario. (2) The decline of China’s GDP, total output, and employment levels is 2–3 times higher than that of Japan, while the difference of the resident welfare levels is sharper, which of China drops 3–5 times of Japan. (3) Structural factors are the main reason for vulnerability differences between China and Japan, including the differences of expenditure structure, factor input structure for production of life requirement sectors, material and energy dependence for the production of industrial sectors, and usage structure of services outputs. Based on these findings, some policy implications and recommendations for fairness issues on climate change adaptation are proposed.  相似文献   

7.
The outcome of patents on environmental (POET) technologies on the EF in the USA has not been comprehensively explored. Therefore, to close this breach in the literature, the present study discovers how patents on ecological technologies affect ecological footprint (EF) in the USA while regulatory for GDP and EC using the Fourier-based approaches. The conclusions of the present study reveal that POET are an important predictor of EF in the USA and cause a reduction in ecological deprivation in the long run; as expected, economic growth negatively affects environmental sustainability. The outcomes suggest that it is possible to resolve conflicts between the economy and the environment by using technological innovation. The USA government must reconsider its policy focus, particularly on coal energy sourcing and industrial energy, while continuing with heavy investments in its ambitious renewable energy technology development plan. Moreover, the government should continue to promote investments in environmental technologies.  相似文献   

8.
This paper presents the findings of the study on treatment of domestic wastewater using a laboratory scale Hybrid Upflow Anaerobic Sludge Blanket (HUASB) reactor. The reactor with a working volume of 5.9 L and plastic cut rings as packing media was operated at varying Hydraulic Retention Time (HRT) for a period of 110 days. While the COD removal varied from 75–86%, the BOD removal was in the range of 70–91%. Methane content in the biogas was 62±3%. VFA levels fluctuating between 100 and 186 mg/L (as acetate) did not pose operational problems such as souring of the reactor. During the treatment, nutrient levels exhibited an increasing trend. HUASB system could be designed with very short HRT of 3.3 hours, which will reduce the treatment cost significantly. It appears to be a promising alternative for the treatment of domestic wastewater in developing countries like India  相似文献   

9.
A total of twenty-five bibliographic reviews were published between 1979 and 2004 in Geostandards Newsletter, subsequently renamed Geostandards and Geoanalytical Research, which list more than 5500 papers. These cited references contain information about geochemical reference materials, analytical methods or address general issues concerning the use of reference materials (protocols for sampling, certification, or new analytical techniques). In support of emerging fields of interest in geoanalysis, frequently associated with environmental research, and reflecting the increased breadth in the topics addressed by the Journal, new reference headings were added over time, while retaining the original style and format of the review. Reference management software was used to extract information from these publications related to methods, reference materials and analytes. Major developments during these 25 years, reflecting both advances in laboratory hardware as well as shifts in research interests, can readily be seen in both the types of reference materials being studied and in nature of the new analytical protocols that were developed. These two topics were the core foci of the twenty-five reviews, though much more information might also be extracted from this extensive resource.  相似文献   

10.
The characteristics of wetland research were investigated by a bibliometric analysis of the top-cited wetland-related articles since 1899 based on the Science Citation Index Expanded database. The analyzed aspects included the distribution of journals, and publications by country, institution, and author, with five indicators including total articles, and independent, collaborative, first-author, and corresponding-author articles. Results showed that 188 articles on wetlands have been cited at least 100 times since their publication year to 2011. The most productive stage was 1991–2000, accounting for approximately seven-tenths of the top-cited articles. The US was the leading country, followed distantly by 25 other countries/territories. The US also held primacy in terms of productive institutions. The US Geological Survey ranked first according to the five indicators. The 188 top-cited articles had 637 authors, among whom W.J. Mitsch published the most first-author and corresponding-author articles. Furthermore, substance circulation (especially of carbon), wetland organisms and vegetation, and modeling methodology were the main focuses of wetland research in the past few years. In 2011, wetland organisms and vegetation were the hottest research topics. These results were coincident with a previous study on total publications, and revealed more-specific characteristics and hotspots of wetland research.  相似文献   

11.
These mature analytical techniques do not show any change in publication level from the previous two years and AAS remains dominant in terms of the number of publications. The last two years have seen fewer technical improvements than in the previous review period. Some interesting papers dealing with uncertainty and quality assurance in INAA were published during 2006–2007. It is suggested that photon activation should be reconsidered because the source of electron accelerators has recently improved. A technique to preconcentrate Se for INAA determination has also been proposed. In the case of AAS, papers on analyte preconcentration continue to be more abundant than those relating to instrumental modification. Sample preparation for AAS is also active and ultrasound‐assisted leaching shows some promising applications. There were an unusual number of reviews concerned with AAS and those important to geological samples are cited here. A technique to preconcentrate Cr in water is presented and a new device to determine As and Se is showing some potential uses. Confocal X‐ray mapping continues to show interesting developments. One group developed a technique to perform XRF inside an oyster and an interesting application of μ‐XRF mapping of sediments is presented. Determination of platinum‐group elements (at μg g1 concentrations) can be carried out very quickly with an improved XRF technique.  相似文献   

12.
Stormwater runoff from urban areas and subsequent stormwater-induced effluents from sewer systems may deteriorate the quality of the receiving water sediments by emitting particulate matter and associated pollutants. However, the relevance of stormwater and combined sewer effluents for the pollution of bed sediments was not yet quantified. Therefore, we applied a multivariate mixing model of composite fingerprints to investigate how much stormwater effluent may contribute to the accumulation of fines and associated pollutants in the bed sediment of the Bode River, Germany. In our study, stormwater and combined sewer effluents contribute about 10 % of the fines accumulated in the bed sediment. As stormwater overflow fines are a major carrier of C, N, P, Cu and Zn, up to 40 % of these pollutants in the bed sediment originate from stormwater effluents. Especially N and Zn have to be seen critically because high nutrient concentrations trigger excessive macrophyte growth within the studied river stretch and Zn contents exceed German sediment quality standards (LAWA 1998) in the bed sediment.  相似文献   

13.
稀土资源储备刻不容缓   总被引：7，自引：0，他引：7  
任忠宝  余良晖 《地球学报》2011,32(4):507-512
本文基于全球稀土资源供需形势和我国储量减少的趋势分析了我国开展稀土资源储备的紧迫性.从储备规避“世贸规则”进行间接控制出口、增强在国际稀土市场的话语权以及降低国家外汇储备风险三个方面阐明了我国开展稀土资源储备的必要性.通过借鉴美国和日本在稀土矿产地和矿产品储备方面的成功经验,结合我国稀土资源储备现状,初步构建了适合我国...  相似文献   

14.
本文基于Web of Science数据库,针对2000-2019年钻井液领域文献进行对比和可视化分析,梳理了钻井液年发文量、发文国家、研究热点和研究机构等信息。结果表明：从年发文量来看,2012年之前全球钻井液发文量增长较慢,而2012年之后钻井液发文量出现猛增。美国发文数量最多,达到1803篇,篇均被引频次达到22.06次。中国发文量为1586篇,但是篇均被引频次只有8.55,论文质量与美国差距巨大。从研究方向来看,能源燃料是钻井液领域的重点研究方向。从关键词共现来看,流变性能、纳米材料、天然气水合物等是钻井液研究的相关热点。期刊《Journal of Petroleum Science and Engineering》在钻井液领域的刊文量最大,达到426篇,是钻井液领域最具影响力的期刊。  相似文献   

15.
Social Ecological System (SES) is the core and highlight of the global change research and sustainability science. Based on Science Citation Index Expanded Database and China National Knowledge Infrastructure, the situation of social ecological system research was analyzed via bibliometrics from 1980 to 2017. The results indicated that: ①The scientific outcomes of social ecological system research are increasing gradually. The developed countries have greatly contributed to it, such as, Sweden and the USA, the leading countries in this field, and Stockholm University is the dominant institution on publication of SES. Cooperation between countries (regions) and institutions is strengthening gradually. ② China is one of the frontier countries in the social ecological system research with a lower increasing speed, its international cooperation and the citation frequency of publications are relatively low, and its international influence should be strengthened in the future. ③ The research highlights are listed as follows: The synergy between social ecological system integrity and social development needs, the complexity and uncertainty of SES, the mechanism between social system and its environmental factors, etc. In addition, under the stress of human activity and global climate change, the research of response and feedback mechanism of SES and policy decision-making are one of the important topics of SES.  相似文献   

16.
《Quaternary Science Reviews》2007,26(22-24):2694-2700
Data on fluvial sequences from around the world, collected as part of IGCP 449, has allowed comparison between such records with the purpose of searching for meaningful patterns. A key finding has been that fluvial incision rates, as measured by the vertical separations of well-dated terrace deposits one from another, and from the modern valley floor (which can be used as a proxy for uplift), are often very similar in different parts of the world but vary significantly between systems on different types of crust. The collection that this paper introduces, coupled with previous IGCP 449 publications cited, confirms that the aim of a worldwide compilation of fluvial archives has been achieved, with a number of syntheses already published.  相似文献   

17.
Florida Bay is Florida’s (USA) largest estuary and has experienced harmful picocyanobacteria blooms for nearly two decades. While nutrient loading is the most commonly cited cause of algal blooms in Florida Bay, the role of zooplankton grazing pressure in bloom occurrence has not been considered. For this study, the spatial and temporal dynamics of cyanobacteria blooms, the microbial food web, microzooplankton and mesozooplankton grazing rates of picoplankton, and the effects of nutrients on plankton groups in Florida Bay were quantified. During the study, cyanobacteria blooms (>3 × 105 cells mL−1) persisted in the eastern and central regions of Florida Bay for more than a year. Locations with elevated abundance of cyanobacteria hosted microzooplankton grazing rates on cyanobacteria that were significantly lower (p < 0.001) and less frequently detectable compared to sites without blooms. Consistent with this observation, cyanobacteria abundances were significantly correlated with ciliates and heterotrophic nanoflagellates at low cyanobacteria densities (p < 0.001) but were not correlated during bloom events. The experimental enrichment of mesozooplankton abundance during blooms yielded a significant decrease in the net growth rate of picoplankton but had the opposite effect when blooms were absent, suggesting that the cascading effect of mesozooplankton grazing on the microbial food web was also altered during blooms. While inorganic nutrient enrichment significantly increased the net growth rates of eukaryotic phytoplankton and heterotrophic bacteria, such nutrient loading had no effect on the net growth rates of cyanobacteria. Hence, this study demonstrates that low rates of zooplankton grazing and low rates of inorganic nutrient loading contribute to the persistence of cyanobacteria blooms in Florida Bay.  相似文献   

18.
Lee  Moon-Gyo  Ha  Jeong-Gon  Cho  Hyung-Ik  Sun  Chang-Guk  Kim  Dong-Soo 《Acta Geotechnica》2021,16(4):1187-1204

Verifying the seismic performance of port structures when the force balance limit is exceeded is important for the performance-based seismic design of gravity-type quay walls. Over the last three decades, performance verification methods have been developed that consider the effects of the design earthquake motion, geotechnical conditions, and structural details on the deformation of a quay wall to accurately predict earthquake-induced damage. In this study, representative performance verification methods (i.e., simplified dynamic analysis methods extending from the Newmark sliding block method and performance-based seismic coefficients developed in Japan) were quantitatively assessed with actual cases of earthquake-damaged quay walls and the results of dynamic centrifuge tests previously conducted under various conditions (i.e., different wall heights, earthquake motions and the thickness of subsoil). The dynamic centrifuge test results suggested directions for improving the performance-based seismic coefficients of the representative methods, while their field applicability and reliability were confirmed according to the actual earthquake records.

  相似文献   

19.
DECOVALEX Project: from 1992 to 2007   总被引：3，自引：0，他引：3  
The DECOVALEX project is a unique international research collaboration, initiated in 1992, for advancing the understanding and mathematical modelling of coupled thermo-hydro-mechanical (THM) and thermo-hydro-mechanical-chemical (THMC) processes in geological systems—subjects of importance for performance assessment of radioactive waste repositories in geological formations. From 1992 up to 2007, the project has made important progress and played a key role in the development of numerical modelling of coupled processes in fractured rocks and buffer/backfill materials. The project has been conducted by research teams supported by a large number of radioactive-waste-management organizations and regulatory authorities, including those of Canada, China, Finland, France, Japan, Germany, Spain, Sweden, UK, and the USA. Through this project, in-depth knowledge has been gained of coupled THM and THMC processes associated with nuclear waste repositories, as well as numerical simulation models for their quantitative analysis. The knowledge accumulated from this project, in the form of a large number of research reports and international journal and conference papers in the open literature, has been applied effectively in the implementation and review of national radioactive-waste-management programmes in the participating countries. This paper presents an overview of the project.  相似文献   

20.
The Lagoon of Venice is a wide, shallow coastal basin that extends for about 50 km along the northwest coast of the Adriatic Sea. The lagoon has been substantially modified through the actions of man over the last century through the artificial control of the hydraulic dynamics of the laggon including the construction of channels to facilitate navigation. The lagoon is subjected to considerable pollutant loading through the drainage of land under cultivation, municipal sewage, and industrial effluents. In this paper are reported the results of observations designed to document recent changes in macroalgal species composition, seasonal cycles of primary producers and nutrient levels, and the effects of the macroalgal community on concentrations of organic and inorganic pollutants. The dominant macroalgae in the lagoon wasUlva rigida, and the levels of plant nutrients and pollutants were influenced by the seasonal cycles of the macroalgal community.  相似文献   

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