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51.
External organic carbon sources are needed to provide electron donors for the denitrification of wastewater with a low COD/NO3--N(C/N) ratio, increasing the treatment cost. The economic strategy is to enhance the bioactivity and/or biodiversity of denitrifiers to efficiently utilize organic substances in wastewater. In this study, novel zero-valent iron(ZVI) composite carriers were prepared and implemented in a suspended carrier biofilm reactor to enhance the bioactivity an... 相似文献
52.
根据对福州开发区阴离子射线管(CRT)产业集群进行调查、访谈和统计分析,实证研究了该产业集群的废物产生特征和管理模式.结果发现,福州CRT产业集群在不断发展壮大的同时,随着主导产品生产规模的扩大以及配套企业的进入,废物的产生总量不断增加,单位主导产品的废物产生强度持续上升,废物种类也逐渐丰富,给区域环境带来的压力不断增大;但同时,产业集群借助其规模和集聚效应,不仅为废物交换和工业共生体系的构建提供了基础平台,而且为专营性废物回收组织和处理处置设施的良好运转营造了外部环境. 相似文献
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Heinz Rüdel Winfried Schröder Karl Theo von der Trenck Gerhard Andreas Wiesmüller 《Environmental science and pollution research international》2009,16(5):486-498
Background Due to the requirements of the EU Water Framework Directive and other legal regulations (e.g., national laws like the German
Federal Soil Protection Act), but also due to the implementation of the new EU chemicals management system REACH, environmental
monitoring will gain increasing importance for the surveillance of environmental quality as well as for the assessment of
chemicals. Against this background, the Work Group on ‘Environmental Monitoring’ of the Division of ‘Environmental Chemistry
and Ecotoxicology’ within the German Chemical Society has compiled a position paper on substance-related environmental monitoring.
Scope Core elements of this position paper are the definitions of important terms like monitoring, exposure monitoring, effect monitoring,
and integrated monitoring. Moreover, temporal and spatial aspects (monitoring of spatial distributions, trend monitoring,
and retrospective monitoring) and their applications are discussed. The main focus of this position paper is the coverage
of aspects which have to be observed for the preparation and implementation of a monitoring program. Essential is the clear
specification of the targets of the monitoring which determine the development of the monitoring concept and its realization,
e.g., if environmental media (compartments) or organisms are most appropriate as samples for the aim of the study. Of course,
also the properties of the target substances are important (e.g., lipophilicity/bioaccumulation as pre-requisite for an exposure
monitoring with organisms). Finally, the monitoring phases of sample planning, sampling, storage and transport of samples,
selection of analytical methods, quality assurance measures as well as reporting are discussed.
Perspectives An important issue for the future is to link the quantification of chemicals in environmental compartments (exposure and pollution
monitoring) more closely to the study of biological effects (effect monitoring) than has been the case up to now. Furthermore,
by inclusion of a spatial differentiation, a comprehensive evaluation of the state of an ecosystem can be obtained and the
relevance of the results improved. Practical examples of monitoring studies which illustrate various aspects covered in this
position paper will be presented in a series of publications by members of the Work Group in the following issues of this
journal.
相似文献
Gerhard Andreas WiesmüllerEmail: |
57.
We report observations of disappearance of Erica tetralix in wet heathland, which is unlikely to be caused by competition, as E. tetralix is dying before its place is taken up by other species. To investigate the causes, we used both old and new data. Results showed that presence of Molinia caerulea and Calluna vulgaris were substantial in the former E. tetralix dominated areas. Measurements of the C/N ratio in the morlayer were between 21 and 26 under the E. tetralix stands. As the expected C/N ratio in a healthy nutrient poor ecosystem like the E. tetralix wet heathland is around 30, this indicates that the ratio is probably decreasing and, correspondingly, the probability of nitrogen leaching from the ecosystem is increasing. The morlayer pH was extremely low—between 3.03 and 3.78. This represents a pH decline since the 1960s, where pH values generally were above 4. This supports the hypothesis that the decrease in morlayer pH is the major factor explaining the disappearance of E. tetralix and that measures to increase pH should be considered as part of the recommendations for relevant future management.
Electronic supplementary material
The online version of this article (doi:10.1007/s13280-012-0251-z) contains supplementary material, which is available to authorized users. 相似文献58.
The objective of our study was to identify how actors from the main socio-economic sectors perceive their interactions and impacts on a sensitive wetland in an arid climate, specifically the salt pans of Chott Merouane in Algeria. The results revealed that there are three main economic stakes including agriculture, livestock production and salt mining, each activity providing a great benefit for local and national populations. The local population perceived that the current activities are conducted in such a way that they created conflict between socio-economic sectors and caused a threat for long term sustainability of the wetlands. The results highlighted the need to initiate an integrated management approach between the different sectors and to develop a shared vision for the territory. 相似文献
59.
Sandra Uthes Katharina Fricke Peter Zander Stefan Sieber Annette Piorr 《Ecological modelling》2010,221(18):2136-2152
The Common Agricultural Policy (CAP), a system of market support instruments, direct income transfers, and rural development measures, has been put through an ongoing reform process in recent decades. This paper introduces three policy impact assessment tools (SIAT, SEAMLESS-IF, MEA-Scope tool) and analyses how these tools have responded to a number of challenges for integrated assessment modelling as reported in the international literature. Significant progress has been made with regard to modelling linkages whereas other challenges, particularly those related to issues of scale and uncertainty management, require further efforts. It is also analysed which CAP instruments are represented and what kinds of effects can be analysed at different scales. Market instruments and direct payments are comparatively well represented, while the ability to model rural development measures is mostly beyond the scope of these tools. Because each tool has found a different solution for coping with the common challenges of integrated assessment modelling, the choice of one of the tools for a particular application depends strongly on the policy questions being asked. The SIAT provides the big picture via its ability to represent broad changes in policy instruments with EU-wide cross-sector impacts. The most comprehensive analysis of agricultural policy instruments can be obtained with SEAMLESS-IF. The MEA-Scope tool complements the other two approaches with detailed regional profiles. 相似文献
60.
The People and Landscape Model (PALM): Towards full integration of human decision-making and biophysical simulation models 总被引:1,自引:0,他引:1
A model for simulating resource flows in a rural subsistence community is described. The People and Landscape Model (PALM) consists of a number of agents representing households, the landscape, and livestock. The landscape is made up of a number of homogeneous land units, or ‘fields’, each represented by an object containing data, methods and properties relevant to the field. Each field object consists of a number of soil layer objects, each of which contains routines to calculate its water balance and carbon and nitrogen dynamics. Organic matter decomposition is simulated by a version of the CENTURY model, while water and nitrogen dynamics are simulated by versions of the routines in the DSSAT crop models. The soil processes are simulated continuously, and vegetation types (crops, weeds, trees) can come and go in a field depending on its management. Crop growth and development are simulated by a generic model based on the DSSAT crop models, and which can be parameterised for different crops. Similarly, livestock growth and resource use is simulated by a generic model which can be parameterised for buffalo, cows, goats, sheep, chickens and pigs. 相似文献