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291.
Hoel AH  Olsen E 《Ambio》2012,41(1):85-95
The prospects of rapid climate change and the potential existence of tipping points in marine ecosystems where nonlinear change may result from them being overstepped, raises the question of strategies for coping with ecosystem change. There is broad agreement that the combined forces of climate change, pollution and increasing economic activities necessitates more comprehensive approaches to oceans management, centering on the concept of ecosystem-based oceans management. This article addresses the Norwegian experience in introducing integrated, ecosystem-based oceans management, emphasizing how climate change, seen as a major long-term driver of change in ecosystems, is addressed in management plans. Understanding the direct effects of climate variability and change on ecosystems and indirect effects on human activities is essential for adaptive planning to be useful in the long-term management of the marine environment.  相似文献   
292.
Plant species distributions are expected to shift and diversity is expected to decline as a result of global climate change, particularly in the Arctic where climate warming is amplified. We have recorded the changes in richness and abundance of vascular plants at Abisko, sub-Arctic Sweden, by re-sampling five studies consisting of seven datasets; one in the mountain birch forest and six at open sites. The oldest study was initiated in 1977–1979 and the latest in 1992. Total species number increased at all sites except for the birch forest site where richness decreased. We found no general pattern in how composition of vascular plants has changed over time. Three species, Calamagrostis lapponica, Carex vaginata and Salix reticulata, showed an overall increase in cover/frequency, while two Equisetum taxa decreased. Instead, we showed that the magnitude and direction of changes in species richness and composition differ among sites.  相似文献   
293.
Assessment of the environmental and radiological consequences of a nuclear accident requires the management of a great deal of data and information as well as the use of predictive models. Computerised Decision Support Systems (CDSS) are essential tools for this kind of complex assessment and for assisting experts with a rational decision process. The present work focuses on the assessment of the main features of selected state-of-the-art CDSS for off-site management of freshwater ecosystems contaminated by radionuclides. This study involved both developers and end-users of the assessed CDSS and was based on practical customisation exercises, installation and application of the decision systems. Potential end-users can benefit from the availability of several ready-to-use CDSS that allow one to run different kinds of models aimed at predicting the behaviour of radionuclides in aquatic ecosystems, evaluating doses to humans, assessing the effectiveness of different kinds of environmental management interventions and ranking these interventions, accounting for their social, economic and environmental impacts. As a result of the present assessment, the importance of CDSS “integration” became apparent: in many circumstances, different CDSS can be used as complementary tools for the decision-making process. The results of this assessment can also be useful for the future development and improvement of the CDSS.  相似文献   
294.
The aim of this study was to evaluate the behavior of Hg, As, and Se in cement production. Two types of cement plants were studied, including the vertical shaft kiln (VSK) and preheater–precalciner kiln (PPK) processes. Determination of Hg, As, and Se in the main material and gas streams were performed. It was found that recycling of particulate matter captured by an air pollution control device caused a significant enrichment of Hg and As inside both processes. The total quantity of Hg entering the process and the quantity emitted to the atmosphere were found to be 10–109 and 6.3–38 mg, respectively, per ton of clinker produced. The average Hg emission was calculated to be around 41% of the total mercury input. The emissions found complied with the European Union (EU) limit and exceeded partly the U.S. limit. Furthermore, it was found that oxidized mercury was the dominant species in the PPK process, whereas the reduced form was dominant in the VSK process, due to the oxidizing and reducing gas conditions, respectively. Regarding the distribution of As and Se, the major amounts were bound to the solid materials, that is, cement clinker and particulate matter. Based on cement production data in China in 2013, the annual emissions of Hg and As were estimated to be in the range of 8.6–52 and 4.1–9.5 tons, respectively.

Implications: There are fairly limited studies on Hg, As, and Se measurements from cement manufacturing facilities in China, and even more limited studies on the behavior in vertical shaft kilns. The needs for increased emission reduction efforts in energy-intensive industries are globally recognized, and an improved understanding of the processes ongoing in a cement kilns system is decisive. Since the processes are complex and almost impossible to recreate in the laboratory, field measurements are indeed important. The findings in the present study were solely based on field measurements and the data are considered to be valuable for the further development of emission reduction technology.  相似文献   
295.
The first part presents a conceptual model of the economic system in its ecological and social context. It is developed via an integration of basic concepts in physical resource theory, animal and human physiology, economic theory and systems ecology. The capacity of the model to support analysis of such complex systems where life is a key system characteristic is high. The conceptual model shows the dependency of the human economy on support by non-renewable and renewable resources from Nature (i.e. ecological source restrictions), as well as the capacity of ecosystems to assimilate wastes (ecological sink restrictions). The analysis focuses general principles; thus, the high level of abstraction results in an apparent simplicity. In the second part, we integrate traditional economic production functions and the conceptual model, which results in the formulation of a biophysically anchored production function (BAPF). The BAPF by itself, and through the system of ecological economic accounts that can be derived from it, represent a toolbox that supports the operationalisation of a sustainable development from micro to macro level. It is coherent with Impredicative Loop Analysis, existing management systems within agricultural sciences, OECD’s principles for sustainable development and the approach of Millennium Ecosystem Assessment. Compared to analytical approaches used in the formulation of sustainability policies in the private and public sphere, based on conceptual models ignoring the complexity when life (bios) is a defining system characteristic, its relevance for the operationalisation of sustainable development approaches infinity. The third part presents results from statistical analysis of relations between gross domestic product and energy supply and some emissions, respectively, for different nations and time periods, delivering values on levels and trends for parameters in the BAPF as well as a first test of the relevance of the BAPF proposed. The paper is ended by a theoretical analysis of the costs of provoking an economic system working under ecological source and sink restrictions to follow exponential growth: The need to decouple economic growth from natural resource use and emissions is highlighted. Otherwise, the erosion of the ecological foundation of the economy with regard to source as well as sink aspects will be a function of exponential growth.  相似文献   
296.
Olof Lindén  Jonas Pålsson 《Ambio》2013,42(6):685-701
The study shows extensive oil contamination of rivers, creeks, and ground waters in Ogoniland, Nigeria. The levels found in the more contaminated sites are high enough to cause severe impacts on the ecosystem and human health: extractable petroleum hydrocarbons (EPHs) (>10-C40) in surface waters up to 7420 μg L−1, drinking water wells show up to 42 200 μg L−1, and benzene up to 9000 μg L−1, more than 900 times the WHO guidelines. EPH concentrations in sediments were up to 17 900 mg kg−1. Polycyclic aromatic hydrocarbons concentrations reached 8.0 mg kg−1, in the most contaminated sites. The contamination has killed large areas of mangroves. Although the natural conditions for degradation of petroleum hydrocarbons are favorable with high temperatures and relatively high rainfall, the recovery of contaminated areas is prevented due to the chronic character of the contamination. Oil spills of varying magnitude originates from facilities and pipelines; leaks from aging, dilapidated, and abandoned infrastructure; and from spills during transport and artisanal refining of stolen oil under very primitive conditions.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-013-0412-8) contains supplementary material, which is available to authorized users.  相似文献   
297.
The abundance of plastics in stomachs of northern fulmars from the North Sea is used in the OSPAR Ecological Quality Objective (EcoQO) for marine litter. The preliminary EcoQO defines acceptable ecological quality as the situation where no more than 10% of fulmars exceed a critical level of 0.1 g of plastic in the stomach. During 2003-2007, 95% of 1295 fulmars sampled in the North Sea had plastic in the stomach (on average 35 pieces weighing 0.31 g) and the critical level of 0.1 g of plastic was exceeded by 58% of birds, with regional variations ranging from 48 to 78%. Long term data for the Netherlands since the 1980s show a decrease of industrial, but an increase of user plastics, with shipping and fisheries as the main sources. The EcoQO is now also used as an indicator for Good Environmental Status in the European Marine Strategy Framework Directive.  相似文献   
298.
299.
The northern fulmar (Fulmarus glacialis) is an interesting candidate for the study of patterns and levels of halogenated organic contaminants (HOCs) since they accumulate high levels of certain HOCs. In the present study we characterized a suite of established and novel HOCs in northern fulmars breeding on Bj?rn?ya in the Norwegian Arctic. A comparison between blood and liver HOC levels was made, and the levels were related to the ratios of heavier to lighter stable isotopes of nitrogen (15)N/(14)N (delta(15)N) and carbon (13)C/(12)C (delta(13)C) in muscle. A significant difference in congener patterns between blood and liver was found. The delta(13)C was not related to HOCs, neither in liver nor in blood. Weak correlations were found between delta(15)N and liver HOC levels. The 2,3,7,8-tetrachlorodibenzo-p-dioxin toxic equivalents (TEQs) in northern fulmars were well above thresholds for reproductive effects in seabirds.  相似文献   
300.
A loamy soil contaminated with 137CsCl 40 years ago was investigated by a sequential extraction technique to determine the effect of ageing on chemical availability of 137Cs. The soil samples were sequentially extracted with H2O, NH4Ac, NH2OH·HCl, H2O2, and HNO3. Extractability of 137Cs decreased in the order: HNO3 > Residual > H2O2 > NH4Ac > NH2OH·HCl > H2O. Only 0.94% in labile fractions (H2O and NH4Ac), while more than 96% was found in the strongly bound fraction (HNO3 and residual). However, the activity percentage in labile fractions was increased to 1.34% after autoclaving treatment, while those in the other fractions did not significantly differ. This indicates that the microbial activity played a role in the 137Cs retention. In the subsequent pot experiments with ryegrass and leek, specific activities in both plants were significantly higher in autoclaved soil than in non-autoclaved soil, and uptake of 137Cs in the five cuts by ryegrass was 25% of the labile 137Cs in the soil. In addition, a positive correlation was found between the amount of 137Cs in labile fractions and that by plant uptake.  相似文献   
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