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1.
本文阐述了一个重现性很好的液相色谱方法,依据EPA 8310方法进行土壤中的PAHs样品的制备和HPLC分析,有很好的回收率,且检出限能够满足法规的要求.HPLC方法包括了二极管阵列及荧光检测器的方法.方法在Agilent 1260 Infinity LC系统上开发,使用4.6×150 mm,5μm色谱柱且方法进行了验证,包括方法耐受性实验.此常规HPLC方法之后又转换到了Agilent 1290 Infinity LC系统上,使用2.1×50 mm1.8μm色谱柱.HPLC与UHPLC方法均比较了精密度,检出限(LOD)和定量限(LOQ).  相似文献   
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With the advancement of computational systems and the development of model integration concepts, complexity of environmental model systems increased. In contrast to that, theory and knowledge about > environmental systems as well as the capability for environmental systems analyses remained, to a large extent, unchanged. As a consequence, model conceptualization, data gathering, and validation, have faced new challenges that hardly can be tackled by modellers alone. In this discourse-like review, we argue that modelling with reliable simulations of human-environmental interactions necessitate linking modelling and simulation research much stronger to science fields such as landscape ecology, community ecology, eco-hydrology, etc. It thus becomes more and more important to identify the adequate degree of complexity in environmental models (which is not only a technical or methodological question), to ensure data availability, and to test model performance. Even equally important, providing problem specific answers to environmental problems using simulation tools requires addressing end-user and stakeholder requirements during early stages of problem development. In doing so, we avoid modelling and simulation as an end of its own.  相似文献   
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Regional Environmental Change - The understanding of how ecosystem services are distributed across the landscape and their change over time provides key information to manage multi-functional...  相似文献   
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This article analyses the benefits and shortcomings of the recently developed decision support systems (DSS) FLUMAGIS, Elbe-DSS, CatchMODS, and MedAction. The analysis elaborates on the following aspects: (i) application area/decision problem, (ii) stakeholder interaction/users involved, (iii) structure of DSS/model structure, (iv) usage of the DSS, and finally (v) most important shortcomings. On the basis of this analysis, we formulate four criteria that we consider essential for the successful use of DSS in landscape and river basin management. The criteria relate to (i) system quality, (ii) user support and user training, (iii) perceived usefulness and (iv) user satisfaction. We can show that the availability of tools and technologies for DSS in landscape and river basin management is good to excellent. However, our investigations indicate that several problems have to be tackled. First of all, data availability and homogenisation, uncertainty analysis and uncertainty propagation and problems with model integration require further attention. Furthermore, the appropriate and methodological stakeholder interaction and the definition of ‘what end-users really need and want’ have been documented as general shortcomings of all four examples of DSS. Thus, we propose an iterative development process that enables social learning of the different groups involved in the development process, because it is easier to design a DSS for a group of stakeholders who actively participate in an iterative process. We also identify two important lines of further development in DSS: the use of interactive visualization tools and the methodology of optimization to inform scenario elaboration and evaluate trade-offs among environmental measures and management alternatives.  相似文献   
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This overview of experimentally induced effects of ozone aims to identify physiological and ecological principles, which can be used to classify the sensitivity to ozone of temperate grassland communities in Europe. The analysis of data from experiments with single plants, binary mixtures and multi-species communities illustrates the difficulties to relate individual responses to communities, and thus to identify grassland communities most at risk. Although there is increasing evidence that communities can be separated into broad classes of ozone sensitivity, the database from experiments under realistic conditions with representative systems is too small to draw firm conclusions. But it appears that risk assessments, based on results from individuals or immature mixtures exposed in chambers, are only applicable to intensively managed, productive grasslands, and that the risk of ozone damage for most of perennial grasslands with lower productivity tends to be less than previously expected.  相似文献   
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The article presents the platform “Pimp your landscape” (PYL), which aims firstly at the support of planners by simulating alternative land-use scenarios and by an evaluation of benefits or risks for regionally important ecosystem services. Second, PYL supports an integration of information on environmental and landscape conditions into impact assessment. Third, PYL supports the integration of impacts of planning measures on ecosystem services. PYL is a modified 2-D cellular automaton with GIS features. The cells have the major attribute “land-use type” and can be supplemented with additional information, such as specifics regarding geology, topography and climate. The GIS features support the delineation of non-cellular infrastructural elements, such as roads or water bodies. An evaluation matrix represents the core element of the system. In this matrix, values in a relative scale from 0 (lowest value) to 100 (highest value) are assigned to the land-use types and infrastructural elements depending on their effect on ecosystem services. The option to configure rules for describing the impact of environmental attributes and proximity effects on cell values and land-use transition probabilities is of particular importance. User interface and usage of the platform are demonstrated by an application case. Constraints and limits of the recent version are discussed, including the need to consider in the evaluation, landscape-structure aspects such as patch size, fragmentation and spatial connectivity. Regarding the further development, it is planned to include the impact of land management practices to support climate change adaptation and mitigation strategies in regional planning.  相似文献   
8.
Stable carbon isotope ratios (delta(13)C) and leaf conductance (g(s)) were measured (2002, 2003) in Holcus lanatus L., Plantago lanceolata L. Ranunculus friesianus (Jord.), and Trifolium pratense L. at two levels of ozone (O(3)) with or without irrigation. In non-irrigated control plots, R. friesianus showed the least negative delta(13)C, and the smallest response to the treatments. Irrigation caused more negative delta(13)C, especially in H. lanatus. Irrespective of irrigation, O(3) increased delta(13)C in relationship to a decrease in g(s) in P. lanceolata and T. pratense. The strongest effect of O(3) on delta(13)C occurred in the absence of irrigation, suggesting that under field conditions lack of moisture in the top soil does not always lead to protection from O(3) uptake. It is concluded that in species such as T. pratense plants can maintain stomatal O(3) uptake during dry periods when roots can reach deeper soil layers where water is not limiting.  相似文献   
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Environmental impacts associated with the use of fossil fuels, rising prices, potential limitations in supply and concerns about regional and national security are driving the development and use of biomass for bioenergy, biofuels and bioproducts. However, the use of biomass does not automatically imply that its production, conversion and use are sustainable. In order to operationalize sustainability assessments of biomass systems, it is crucial to identify critical criteria, but keep their number and measurement at a manageable level. The selection of these criteria can vary depending on individual's expertise, geographical region where they work, and spatial scale they are focused on. No clear consensus has yet emerged on what experts consider as critical indicators of sustainability. Objectives of this paper were to analyze how key experts perceive the 35 sustainability criteria for bioenergy found in emerging sustainability assessment frameworks and to identify levels of agreement and uncertainty. Experts were asked to rate the criteria for attributes of relevance, practicality, reliability, and importance.Perceptions of the importance of the 35 criteria varied among the experts surveyed. Only two criteria, energy balance and greenhouse gas balance, were perceived as critical by more than half of the respondents. Social criteria and locally applied criteria were generally ranked low for all four attributes. Seven of the 12 criteria scored as most important focused on environmental issues, four were social and only one was economic. Of the 12 most important criteria, seven were ranked low in practicality and reliability indicating that mechanisms to assess a number of important criteria need to be developed. The spatial scale the experts worked at and their profession explained most of the differences in importance ranking between experts, while regional focus had minimal effect. Criteria that were ranked low for importance, were characterized by a lack of consensus, suggesting the need for further debate regarding their inclusion in sustainability assessments.Outcomes of the survey provide a foundation for further discussions and development of sustainability assessments for bioenergy systems and may also provide a basis for assessing individual bioenergy projects within their specific geographic, ecological, societal, and technological context and scale.  相似文献   
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