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621.
What are the management challenges and opportunities of bio-energy chains for both running their business efficiently and effectively and fostering the relationships with most relevant external stakeholders? This question is approached by systematically reviewing papers at the interface of bio-energy and supply chain or logistics issues. The review conducted as content analysis is based on an analytic framework that conceives bio-energy chains between challenges and benefits of bio-energy production with simultaneous internal supply chain management and external stakeholder management needs. Smartly designed and operated bio-energy projects hold promising potentials of contributing to sustainable development by both mitigating climate change and strengthening adaptation capabilities. Our analysis distils specific strategies and success factors for tapping this potential on two levels: On a supply chain level, individually adapted and designed supply chain systems relying on trustful information exchange, cooperation and relational governance safeguard profitability while holding adverse ecological and social impacts of operation down; they allow, for instance, minimising costs and emissions, implementing new technologies, and coping with environmental uncertainties such as crop failures and volatile prices. On a stakeholder level, governments as key actors for designing the future legal framework of bio-energy are primary targets for lobbying activities of bio-energy representatives. Respective arguments may focus on economic development and job generation. By minimising its adverse impacts on society and eco-systems and by communicating these efforts credibly, bio-energy warrants its superiority over fossil energy systems. Involving NGOs and residents in early stages of bio-energy projects via transparent two-way communication considerably increase societal acceptance.  相似文献   
622.
This study aimed at statistically investigating the association between the internal exposure of children and young adults to uranium (U) and epidemiologically relevant external determinants of exposure. The investigation was performed with data from two studies within the framework of the German health-related environmental monitoring program: The German Environmental Survey for Children (GerES IV) conducted by the Federal Environment Agency (Umweltbundesamt) with data on 1,780 children 3–14 years of age and their home environment and the German Environmental Specimen Bank (ESB, section: human specimens) with data on 2,253 students 20–29 years of age. Both studies provided data on the U levels in human urine for all probands. GerES IV furthermore provided an extensive environmental and demographic database on, e.g., U levels in drinking water. The data from GerES IV and ESB were linked by GIS to spatially relevant exposure information, including background values of U in stream sediments and in upper and lower soils, U levels in mosses and particulate matter in the lower atmosphere, precipitation and elevation as well as forest density. Bivariate correlation analysis and two decision tree models showed moderate but significant associations between U in human urine and U levels in drinking water, stream sediments and upper and lower soils. Future investigations considering additional epidemiologically relevant data sets may differentiate the results. Furthermore, the sample design of future environmental epidemiology studies should take the spatial evaluation of the data into greater account.  相似文献   
623.
This paper examines the relationship between quality of life indicators and the gross value of minerals production from Australian regions. We used quality of life indicators, aggregated for 71 local government areas containing mining activities, of household income, housing affordability, access to communication services, educational attainment, life expectancy, and unemployment. We find no evidence of systematic negative associations between quality of life and the gross value of minerals production. Instead, mining activity has a positive impact on incomes, housing affordability, communication access, education and employment across regional and remote Australia. Whilst we do not establish causality between mining activity and quality of life, our analysis prompts a rethink of the resource curse as it applies within a single country. We did not find evidence of a resource curse, at the local government level, in Australia’s mining regions. Nevertheless, we note observations by many other researchers of negative social impacts on specific demographic sectors, localities, families of fly-in fly-out mining operations, and individuals. This contrast may be a scale issue, with the regional benefits of mineral wealth masking highly localised inequalities and disadvantage. We suggest that there is a need to better understand these impacts and, more importantly, the types of policy mechanisms government and industry can adopt to mitigate or avoid them.  相似文献   
624.
Many of today's most urgent environmental problems arise from increasing volumes of worldwide production and consumption and the associated use of natural resources, including renewable and non-renewable raw materials, energy, water and land. Solid indicators to measure different dimensions of anthropogenic resource use are essential for designing appropriate policy measures for a sustainable management of these resources. Based on a brief review of the current state of the art of resource use indicators, this paper suggests a new set of complementary resource use indicators, combining existing measures for resource use. The suggested indicator set covers the core resource input categories of materials, water and land area and includes the output category of greenhouse gas emissions. This set can be applied consistently from the micro level of products and companies up to the macro level of countries and world regions. All suggested indicators take a life-cycle wide perspective on production and consumption activities. This set of indicators deals with the issue of the overall scale of the human production and consumption system. It can be regarded as the general indicator framework, based on which more specific indicators, for example, on different environmental impacts related to natural resource use, can be calculated.  相似文献   
625.
Mate choice copying was mostly described as a strategy employed by females to assess the quality of potential mates, but also males can copy other males’ mate choice. An open question in this context is whether and how copying males evaluate sperm competition risk, as mating with a female that has already copulated with another male obviously sets the stage for intense sperm competition (i.e., in species with internal fertilization). Using the livebearing Atlantic molly (Poecilia mexicana) as a model, we asked (a) whether males of that species indeed copy other males’ choices, and if they do so, (b) whether copying males strategically adjust their behavior to sperm competition risk. We used an approach where focal males could first choose to associate with a large or a small stimulus female. Mate choice tests were then repeated after an “observation phase” during which either no model male was present (treatment 1, control) or the previously non-preferred female could be seen associating (treatment 2) or physically interacting (treatment 3) with a model male. We found that, after the observation phase, males spent considerably more time with the previously non-preferred female in treatment (2), i.e., they copied the model male’s choice. This effect was much weaker during treatment (3) where sexual interactions between the model male and the formerly non-preferred female were allowed. Males, therefore, seem to adjust their copying behavior strategically to the perceived risk of sperm competition.  相似文献   
626.
Systematic sampling and analysis were performed to investigate the dynamics and the origin of suspended particulate matter smaller than 2.5 μm in diameter (PM(2.5)), in Beijing, China from 2005 to 2008. Identifying the source of PM(2.5) was the main goal of this project, which was funded by the German Research Foundation (DFG). The concentrations of 19 elements, black carbon (BC) and the total mass in 158 weekly PM(2.5) samples were measured. The statistical evaluation of the data from factor analysis (FA) identifies four main sources responsible for PM(2.5) in Beijing: (1) a combination of long-range transport geogenic soil particles, geogenic-like particles from construction sites and the anthropogenic emissions from steel factories; (2) road traffic, industry emissions and domestic heating; (3) local re-suspended soil particles; (4) re-suspended particles from refuse disposal/landfills and uncontrolled dumped waste. Special attention has been paid to seven high concentration "episodes", which were further analyzed by FA, enrichment factor analysis (EF), elemental signatures and backward-trajectory analysis. These results suggest that long-range transport soil particles contribute much to the high concentration of PM(2.5) during dust days. This is supported by mineral analysis which showed a clear imprint of component in PM(2.5). Furthermore, the ratios of Mg/Al have been proved to be a good signature to trace back different source areas. The Pb/Ti ratio allows the distinction between periods of predominant anthropogenic and geogenic sources during high concentration episodes. Backward-trajectory analysis clearly shows the origins of these episodes, which partly corroborate the FA and EF results. This study is only a small contribution to the understanding of the meteorological and source driven dynamics of PM(2.5) concentrations.  相似文献   
627.
Nature-based solutions (NBS), understood as actions that use ecosystem processes to address societal needs, can play important roles to future-proof river landscape development for people and nature. However, knowledge gaps exist how NBS can be planned and implemented at landscape scales. This Special Issue brings together insights and experiences from studies of assessing, planning, and implementing NBS in river landscapes in Europe and beyond. It addresses three research fields: (i) NBS effects, looking at the effectiveness of NBS to achieve ecological, social, and/or economic outcomes, (ii) NBS planning, focusing on approaches for planning and designing NBS, and (iii) NBS governance, relating to governance and business models for implementation. The twelve contributions deliver evidence on how NBS outperform conventional, rather technical solutions, provide guidance and tools to operationalize the NBS concept into practice, and showcase successful governance models of NBS in different contexts. The editorial ends with an outlook on further research needs.  相似文献   
628.
This article reflects on the fundamentals of first and second modernity and its usefulness and practicability for problem formulation and solving in the context of water management practices in Iran. It is argued that the current water crisis in Iran resulted from modernization based on first modernity paradigms, and second modernity concepts are used to present a framework for new water management approaches. Based on the concept of sub-political arrangements, we suggest that water management issues can be treated best in process-based ways under a reflexive modernity point of view.  相似文献   
629.
The production of energy crops in Germany is a growing agronomic sector and is expected to occupy a substantial share of farmland in the near future. At the same time, there are concerns that energy crops might cause increased nitrogen pollution of soil water, surface water and groundwater. Therefore, the Federal State of Saxony, Germany, funded a study on potential effects of an intensified cultivation of energy crops. In frame of this study, we used the Web GIS-based model STOFFBILANZ to simulate N leaching from the rooting zone and N loads of surface water for a reference scenario and an energy crop scenario. For the reference scenario, we used data representing the crop cultivation for the year 2005 at municipality level. We found that the total loads for N leaching from the rooting zone of cropland are highest for the loess region (8,067 t year?1), followed by mountainous region (6,797 t year?1) and lowland (5,443 t year?1). However, highest N fluxes in the leachate from rooting zones have been simulated for lowland (40.6 kg ha?1 year?1) and mountainous region (37.1 kg ha?1 year?1), while nitrate concentrations of leachate were highest for the lowland (101.8 mg l?1). In terms of diffuse N input into surface water, the mountainous region is the most important source area (total N load 6,380 t year?1, flux 34.6 kg ha?1 year?1). Retention by in-stream processes accounts for 15 % (3,784 t year?1) of the total N load leaving the study area (25,136 t year?1). In the 2020 energy crop scenario, shares of rape and silage maize (id., ensiled corn) were limited for each municipality to a maximum of 25 and 33 %, respectively. The conversion of grasslands to crop farming was not allowed. Under these conditions, we found slight to substantial reductions of nitrogen loads for leachate from the rooting zone and for surface waters. The simulated reduction depends strongly on local conditions. Only small reductions (ca. 4–8 %) were found for the lowlands and mountainous regions of Saxony, while reductions for the loess region were substantial (ca. 22 %). A major outcome of our study is that the cultivation of energy crops might reduce N loss if certain preconditions are assumed, for example, without conversion of grasslands to crop farming. However, effects might vary widely depending on local conditions.  相似文献   
630.
Wash water in waterworks: contaminants and process options for reclamation   总被引:1,自引:0,他引:1  
Reclamation of clean water from filter backwash water was studied through pilot-scale experiments.The pilot plant consisted of clarification,sand-filtration,and ultrafiltration modules in sequence,with a provision to bypass the sand filter.Clean water that conformed to World Health Organization (WHO) guidelines on Potable Quality was reclaimed.Turbidity,aluminum and iron were found to be critical contaminants in process selection and design.Clarification,followed by sand filtration,was found to be the minim...  相似文献   
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