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1.
This study aimed at cross-border mapping metal loads in mosses in eight European countries in 1990, 1995, and 2000 and at investigating confounding factors. Geostatistics was used for mapping, indicating high local variances but clear spatial autocorrelations. Inference statistics identified differences of metal concentrations in mosses on both sides of the national borders. However, geostatistical analyses did not ascertain discontinuities of metal concentrations in mosses at national borders due to sample analysis in different laboratories applying a range of analytical techniques. Applying Classification and Regression Trees (CART) to the German moss data as an example, the local variation in metal concentrations in mosses were proved to depend mostly on different moss species, potential local emission sources, canopy drip and precipitation.  相似文献   

2.
Anthropogenic-induced water quality pollution is a major environmental problem in freshwater ecosystems today. As a result of this, eutrophication of lakes occurs. Population and economic development are key drivers of water resource pollution. To evaluate how growth in the riparian population and in the gross domestic product (GDP) with unplanned development affects the water quality of the lake, this paper evaluates Lake Victoria Kenyan waters basin. Waters quality data between 1990 and 2012 were analyzed along with reviews of published literature, papers, and reports. The nitrate-nitrogen (NO3-N), soluble phosphorus (PO4-P), chlorophyll a, and Secchi transparencies were evaluated as they are key water quality indicators. The NO3-N increased from 10 μg l?1 in 1990 to 98 μg 1?1 in 2008, while PO4-P increased from 4 μg l?1 in 1990 to 57 μg l?1 in 2008. The population and economic growth of Kenya are increasing with both having minimums in 1990 of 24.143 million people and 12.18 billion US dollars, to maximums in 2010 of 39.742 million people and 32.163 billion US dollars, respectively. A Secchi transparency is reducing with time, indicating an increasing pollution. This was confirmed by an increase in aquatic vegetation using an analysis of moderate resolution imaging spectroradiometer (MODIS) images of 2000 and 2012 of Kenyan waters. This study found that increasing population and GDP increases pollution discharge thus polluting lakes. One of major factors causing lake water pollution is the unplanned or poor waste management policy and service.  相似文献   

3.
Liu J  Zhan J  Deng X 《Ambio》2005,34(6):450-455
Along with its economic reform, China has experienced a rapid urbanization. This study mapped urban land expansion in China using high-resolution Landsat Thematic Mapper and Enhanced Thematic Mapper data of 1989/1990, 1995/1996 and 1999/2000 and analyzed its expansion modes and the driving forces underlying this process during 1990-2000. Our results show that China's urban land increased by 817 thousand hectares, of which 80.8% occurred during 1990-1995 and 19.2% during 1995-2000. It was also found that China's urban expansion had high spatial and temporal differences, such as four expansion modes, concentric, leapfrog, linear and multi-nuclei, and their combinations coexisted and expanded urban land area in the second 5 y was much less than that of the first 5 y. Case studies of the 13 mega cities showed that urban expansion had been largely driven by demographic change, economic growth, and changes in land use policies and regulations.  相似文献   

4.
The method of land cover accounting described in this paper has been applied in the Czech Republic. Land cover data have been obtained from the CORINE Land Cover national database produced in the early 1990s. Similarly, satellite images from the late 1970s were used to get another database for change detection. Coefficients estimating the contribution of every land cover category to the particular economic sector or activity were established. Then, the changes in land cover can indicate consequences for economic development in sectors and vice versa. The landscape changes were compared with economic parameters produced by the statistical office. Future development of this approach could provide a tool for economic scenarios modelling regarding the reflection of economic activity in the environment.  相似文献   

5.
Nonylphenols and nonylphenol-ethoxylates were detected in the water and sediment samples from the German Bight of the North Sea. Additionally bis (4-chlorophenyl)-sulfone and linear alkylbenzenesulfonates (LAS) were detected in marine waters. Proof of identification is given by comparison of spectral and chromatographic data from the compounds in sample extracts to those obtained from pure standards. In extracts obtained from water samples taken in 1990 and 1995 the concentrations of nonylphenols and bis-(4-chlorophenyl)-sulfone were compared for each year. The concentrations of nonylphenols in seawater varied from 0.7 to 4.4 ng/l while in the Elbe estuary about 33 ng/l were found. In water samples taken in 1998 nonylphenol-polyethoxylates could not be determined, whereas LAS concentrations of 30 ng/l were confirmed by HPLC-MS/MS. The concentrations of bis (4-chlorophenyl)-sulfone ranged from 0.18 to 2.2 ng/l. In sediment samples LAS concentrations of 39-109 ng/g dry weight were determined.  相似文献   

6.
本文用计量经济学的方法通过对中国、日本、美国的时间序列分析和1990年的全球截面数据分析,探讨了经济增长与CO2排放的关系。并重点分析了人口增长、能源消费强度变化的人均碳排放的影响。分析表明从政策角度而言,人均碳排放与人均GDP之间不存在Kuznets曲线。人口增长和人均GDP的增加是人均碳排放增加的主要来源,而GDP能源消费强度的下降则是碳排放减少的重要来源。  相似文献   

7.
《Chemosphere》1996,33(1):159-176
This paper provides the first time series estimates of global anthropogenic methane emissions from the mid-19th century to the present. Our purpose is to provide time series estimates of anthropogenic methane emissions for global climate models estimated or calibrated using historical time series data. Previous estimates of methane emissions include “top-down” (deconvolution) estimates of total emissions, estimates of global anthropogenic emissions for the 16th century, and various estimates of anthropogenic and natural emissions in the 1980s and 1990s. This study uses previously published point estimates for the 16th century and the 1980s and early 1990s and a variety of historical time series of proxy variables to estimate a time series of global anthropogenic methane emissions. We find that anthropogenic methane emissions have increased from about 80 million tonnes per annum in 1860 to about 380 million tonnes in 1990. The relative importance of various emission sources changes over time. The rate of increase now may be slowing. A comparison with the estimates generated by Khalil and Rasmussen suggests that natural sources of methane have declined over the period. There are, however, great uncertainties in these estimates which future research may be able to reduce.  相似文献   

8.
本文主要研究人口增长、经济增长、技术变化三大因素对环境质量变化的影响。作者提出环境变迁曲线,与人口转变曲线、工业化过程相联系,并划分了环境变迁四个阶段。根据环境变迁过程以及动因,在国际比较范围内,进一步说明了中国环境变迁的特点。作者认为,强化减少污染型技术因素是改善环境质量的主要途径,与此同时,坚持控制人口增长,以减少环境压力。  相似文献   

9.
Goal, Scope and Background Ethoxyresorufin-O-deethylase (EROD) is a well-accepted marker for biological effects in fish and is, therefore, part of numerous monitoring programmes. EROD activity was measured in livers of dab (Limanda limanda) from the German Bight (North Sea) from 1995 to 2003. The aim of the present long-term study was (a) time trend monitoring of EROD activity of dab from the German Bight and (b) to elucidate the needs for a successful application of EROD activity as an early warning system. Methods. EROD activities were determined fluorimetrically in dab liver microsomes, using resorufin as an external standard. The limit of detection (LD) and the limit of quantification (LQ) were calculated. Results were referred to protein concentrations. Results and Discussion. EROD activities of 610 female dab caught in different seasons between January 1995 and August 2003 were analyzed individually. Activities varied from 〈 LD to 1768 pmol/(min mg protein) and showed an annual cycle as well as significant differences between the years. Highest EROD activities were observed in early summer and lowest activities during the winter period. In autumn 2002, significantly elevated EROD activities were detected, possibly related to effects of the River Elbe flood event. Two scenarios with different EROD baseline data are presented to discuss the prerequisites for the use of EROD as a monitoring tool. The comparison of these scenarios underlines the importance of appropriate season-specific baseline data. Conclusion. The use of EROD as an early warning tool for contaminant effects in dab in the German Bight has different prospects during the year, because, due to the high background variability, elevated EROD activities are less easy to detect in spring/summer than during the remaining times of the year. Recommendation and Outlook. The availability of site-specific data on the EROD baseline level, its random variation and its annual cycle is a necessary prerequisite for monitoring. If monitoring is to be carried out only for a limited time period of the year, a season with low background variability in EROD activity (autumn) should be chosen to avoid the need for a compensation of the temperature-triggered shift in sexual cycles and the resulting changes in EROD activity.  相似文献   

10.
Owing to their relative underdevelopment, the 'cohesion' countries of the European Union have been allowed to increase emissions above the 1990 base within the EU 'envelope'. However, they face daunting challenges in meeting the agreed targets, because it requires breaking the link between rising gross domestic product and rising energy consumption at a relatively early stage in the economic development cycle. This paper examines the extreme case of Ireland, which is experiencing the most rapid growth in the EU. It shows that Ireland has already reached its emissions ceiling. The best opportunities for reducing emissions lie in energy supply, industry, and the household sector. A mix of policy instruments is required. Emissions trading seems to be the most effective policy instrument for reducing greenhouse gas emissions from energy supply and large industry. Such a policy would provide a stimulus for continuous improvement, without which Ireland's limit will be breached.  相似文献   

11.
Material and energy flows (together with human appropriation of land) are considered the key cause of environmental problems. This paper describes the application of economy-wide material flow accounting and analysis to the economy of the Czech Republic for 1990-2002. The results show a decrease of material intensity and decoupling of the economic growth from environmental pressure. The second part of the paper treats an important issue of uncertainties related to economy-wide material flow indicators in the Czech Republic. The results point out that the high uncertainties related to some material flow indicators may be an obstacle to their applicability.  相似文献   

12.
The Pennsylvania greenhouse gas (GHG) emissions inventory presented in this paper provides detailed estimates of emissions and their sources for the six major categories of GHGs. The inventory was compiled using the current U.S. Environment Protection Agency methodology, which applies emissions factors to socioeconomic data, such as fossil energy use, vehicle miles traveled, and industrial production. The paper also contains an assessment of the methodology and suggestions for improving accounting with respect to process, sectoral, and geographic considerations. The study found that Pennsylvania emitted 77.4 million metric tons carbon equivalent of GHGs in 1990 and that this total increased by 3% to 79.8 million metric tons carbon equivalent by 1999. Despite this increase, however, the state's percentage contribution to the United States total declined during the decade. Pennsylvania's carbon dioxide (CO2) emissions from fossil fuels represented 92.4% of 1990 totals and declined to 90.5% in 1999. Electricity generation was the largest single source of CO2 emissions, being responsible for 38% of fossil fuel CO2 emissions in 1990 and 40% of the total in 1999. Transportation emissions accounted for the largest increases in emissions between 1990 and 1999, whereas industrial emissions accounted for the largest decrease. The overall trend indicates that Pennsylvania has been able to weaken the relationship between GHG emissions and economic growth.  相似文献   

13.
Islas J  Manzini F  Martínez M 《Ambio》2002,31(1):35-39
This study presents 4 scenarios relating to the environmental futures of electricity generation in Mexico up to the year 2025. The first scenario emphasizes the use of oil products, particularly fuel oil, and represents the historic path of Mexico's energy policy. The second scenario prioritizes the use of natural gas, reflecting the energy consumption pattern that arose in the mid-1990s as a result of reforms in the energy sector. In the third scenario, the high participation of renewable sources of energy is considered feasible from a technical and economic point of view. The fourth scenario takes into account the present- and medium-term use of natural-gas technologies that the energy reform has produced, but after 2007 a high and feasible participation of renewable sources of energy is considered. The 4 scenarios are evaluated up to the year 2025 in terms of greenhouse gases (GHG) and acid rain precursor gases (ARPG).  相似文献   

14.
Levels of α-, β-, and γ-hexabromocyclododecane (HBCD) were determined in pooled eggs from herring gulls (Larus argentatus) sampled on three bird sanctuaries near the German North Sea coast between 1988 and 2008 (Mellum and Trischen) and the German Baltic Sea coast between 1998 and 2008 (Heuwiese) and archived by the German Environmental Specimen Bank. Pressurized fluid extraction, gel permeation chromatography, and LC-MS/MS using 13C12-labelled isotope standards and a chiral column were applied. α-HBCD was the dominating diastereomer and ranged between 3.7 and 107 ng g−1 lw while β- and γ-HBCD were throughout close to LOQ. The highest α-HBCD concentration was found in eggs from Mellum sampled in the year 2000. Interestingly, HBCD in eggs from the three islands displayed similar time courses with levels increasing to a peak contamination around 2000 and decreasing levels ever since. Chiral signatures of α-HBCD in eggs differed among the islands but indicated a preferential enrichment of the first eluting enantiomer (−)-α-HBCD.  相似文献   

15.
Section 812 of the Clean Air Act Amendments (CAAA) of 1990 requires the U.S. Environmental Protection Agency (EPA) to perform periodic, comprehensive analyses of the total costs and total benefits of programs implemented pursuant to the CAAA. The first prospective analysis was completed in 1999. The second prospective analysis was initiated during 2005. The first step in the second prospective analysis was the development of base and projection year emission estimates that will be used to generate benefit estimates of CAAA programs. This paper describes the analysis, methods, and results of the recently completed emission projections. There are several unique features of this analysis. One is the use of consistent economic assumptions from the Department of Energy's Annual Energy Outlook 2005 (AEO 2005) projections as the basis for estimating 2010 and 2020 emissions for all sectors. Another is the analysis of the different emissions paths for both with and without CAAA scenarios. Other features of this analysis include being the first EPA analysis that uses the 2002 National Emission Inventory files as the basis for making 48-state emission projections, incorporating control factor files from the Regional Planning Organizations (RPOs) that had completed emission projections at the time the analysis was performed, and modeling the emission benefits of the expected adoption of measures to meet the 8-hr ozone National Ambient Air Quality Standards (NAAQS), the Clean Air Visibility Rule, and the PM2.5 NAAQS. This analysis shows that the 1990 CAAA have produced significant reductions in criteria pollutant emissions since 1990 and that these emission reductions are expected to continue through 2020. CAAA provisions have reduced volatile organic compound (VOC) emissions by approximately 7 million t/yr by 2000, and are estimated to produce associated VOC emission reductions of 16.7 million t by 2020. Total oxides of nitrogen (NO(x)) emission reductions attributable to the CAAA are 5, 12, and 17 million t in 2000, 2010, and 2020, respectively. Sulfur dioxide (SO2) emission benefits during the study period are dominated by electricity-generating unit (EGU) SO2 emission reductions. These EGU emission benefits go from 7.5 million t reduced in 2000 to 15 million t reduced in 2020.  相似文献   

16.
Global sulfur emissions from 1850 to 2000   总被引:2,自引:0,他引:2  
Stern DI 《Chemosphere》2005,58(2):163-175
The ASL database provides continuous time-series of sulfur emissions for most countries in the World from 1850 to 1990, but academic and official estimates for the 1990s either do not cover all years or countries. This paper develops continuous time series of sulfur emissions by country for the period 1850-2000 with a particular focus on developments in the 1990s. Global estimates for 1996-2000 are the first that are based on actual observed data. Raw estimates are obtained in two ways. For countries and years with existing published data I compile and integrate that data. Previously published data covers the majority of emissions and almost all countries have published emissions for at least 1995. For the remaining countries and for missing years for countries with some published data, I interpolate or extrapolate estimates using either an econometric emissions frontier model, an environmental Kuznets curve model, or a simple extrapolation, depending on the availability of data. Finally, I discuss the main movements in global and regional emissions in the 1990s and earlier decades and compare the results to other studies. Global emissions peaked in 1989 and declined rapidly thereafter. The locus of emissions shifted towards East and South Asia, but even this region peaked in 1996. My estimates for the 1990s show a much more rapid decline than other global studies, reflecting the view that technological progress in reducing sulfur based pollution has been rapid and is beginning to diffuse worldwide.  相似文献   

17.
AMESA (adsorption method for sampling of dioxins) is a fully automatic system for long term monitoring of dioxin emissions from industrial processes based on the adsorption method. The system has been tested and undergoing a certification procedure according to the German guidelines for certification of systems for continuous monitoring of special substances. The certification covered parameters such as disposability of the system, reproducibility of the results and comparability of the sampling method with German and European standard methods. Furthermore break through, blanks and sample storability were investigated. The results prove that AMESA is a state of the art sampling system for continuous monitoring of dioxin/furan emissions.  相似文献   

18.
Oyster samples from 53 Gulf of Mexico coastal sites were collected and analyzed for butyltins during 1989, 1990, and 1991. The geometric-mean tributylin concentrations were 85, 30, and 43 ng Sn/g for 1989, 1990, and 1991, respectively. The tributyltin concentrations are best represented by a log-normal distribution. A decline in the butyltin concentrations at sites with relatively low butyltin concentrations for 1989 compared with 1990 and 1991 was observed, and, at relatively high butyltin concentrations (> 400 ng Sn/g), there was hardly any difference between 1989 and 1991, but lower concentrations were present in 1990. Continued monitoring is needed in order to determine if butyltin contamination of the coastal marine environment is decreasing in response to use limitations.  相似文献   

19.
The instrumental period of climate history began in the 18th century with the commencement of routine weather observations at fixed sites. Estimates of global-mean climate (e.g. temperature and precipitation) were not possible, however, until the establishment of extensive observing networks midway through the 19th century. This paper reviews our knowledge of global climate change in the instrumental period. Time series of global-mean temperature and precipitation are examined and a comparison is made between two independent 30-year climatologies: 1931-1960 and 1961-1990. Examples are also provided of regional-scale climate changes. Such assessments are important for two reasons. First, they establish the variability of climate on the time-scale of decades, time-scales upon which it is reasonable to plan economic and socio-political activities. Second, and more specifically, they enable us to quantify the magnitude of global-mean climate change which has occurred over this period. Such detailed diagnostic climate information is a necessary, although not sufficient, prerequisite for the detection of global-scale warming which may have occurred due to the enhanced greenhouse effect. Some attention is given to explanations of the observed changes in global-mean climate.  相似文献   

20.
Cadmium, lead, mercury, copper, nickel, zinc, and arsenic were analyzed in suspended particulate matter (SPM), zebra mussels, and bream sampled yearly under the program of the German Environmental Specimen Bank (ESB) in the rivers Rhine, Elbe, Danube, Saar, Mulde, and Saale and in Lake Belau. Temporal and spatial trends were analyzed, correlations between metal levels in different specimen types assessed, and sampling sites ranked according to their metal levels by calculating a Multi-Metal Index (MMI) for every specimen type and site. SPM: Highest metal loads were detected in Mulde, Saale, and Elbe right downstream of the Saale confluence. In the Elbe, metal loads in SPM were mostly highest in the upper and middle section of the river while in Rhine and Saar concentrations increased downstream. Temporal trends since 2005 were detected only at three sites. Zebra mussel: MMIs were highest in the tidal section of the Elbe and the lower Rhine and lowest in Lake Belau and the upper Danube. Different temporal trends were detected since the early 1990s depending on site and metal. Bream: As, Pb, Cu, and Hg were analyzed in muscle tissue and Pb, Cd, Cu, and Zn in liver. For both tissues, MMIs were highest in Mulde and Saale and the lower and middle Elbe. Since the early 1990s, Hg, Pb, and Cu decreased in bream muscle at many sites while As increased at 6 of the 17 sites. The findings indicate that Hg, Pb, and Cu have obviously decreased in many freshwater ecosystems in recent years, whereas As and Ni levels have increased at several sites. Metal levels and temporal trends mostly differed between the specimen types under investigation and only few correlations between specimen types were detected. This underlines the importance of including different components of an ecosystem when assessing its environmental quality.  相似文献   

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