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241.
To increase the awareness of society to the challenges of global food security, we developed five contrasting global and European scenarios for 2050 and used these to identify important issues for future agricultural research. Using a scenario development method known as morphological analysis, scenarios were constructed that took economic, political, technical, and environmental factors into account. With the scenarios as a starting point future challenges were discussed and research issues and questions were identified in an interactive process with stakeholders and researchers. Based on the outcome of this process, six socioeconomic and biophysical overarching challenges for future agricultural were formulated and related research issues identified. The outcome was compared with research priorities generated in five other research programs. In comparison, our research questions focus more on societal values and the role of consumers in influencing agricultural production, as well as on policy formulation and resolving conflicting goals, areas that are presently under-represented in agricultural research. The partly new and more interdisciplinary research priorities identified in Future Agriculture compared to other programs analyzed are likely a result of the methodological approach used, combining scenarios and interaction between stakeholders and researchers.  相似文献   
242.
A limited battle involving the nuclear arsenals of India and Pakistan would have significant climatic impacts upon agricultural crop production in the United States; corn, soybeans, and winter wheat yields would be significantly reduced in the Corn Belt region of the US. The most severe impacts would occur during the second year after the modeled nuclear battle.  相似文献   
243.
Food chain models are essential tools to assess risks of soil contamination in view of product quality including fodder crops and animal products. Here we link soil to plant transfer (SPT) models for potentially toxic elements (PTEs) including As, Ba, Cd, Co, Cu, Hg, Ni, Pb, Sb, U and Zn with models describing accumulation in animal organs. Current EU standards for food products and acceptable daily intake levels (ADI) for humans were used as critical limits. The combined model is used to assess the impact of soil contamination on animal health, product quality and human health using data from 100 arable fields. Results indicate that 42 existing arable fields near industrial and mining sites are unsuitable for animal grazing in view of food safety due to elevated intake of Cd, Cu, Hg and Pb by cows and sheep. At 10 sites daily intake levels of As by cows exceeded threshold concentrations regarding the quality of animal products.The food chain model also was used inversely to derive soil threshold concentrations in view of EU fodder standards. Calculated threshold levels in soil for As, Cd, Cu, Pb, Hg and Zn appear to be in line with those proposed or used in other EU countries. As such the approach applied here can form a conceptual basis for a more harmonized risk assessment strategy regarding the protection of animal and human health.  相似文献   
244.
To diagnose environmental nitrogen (N) load from food consumption and to suggest preventive measures, this study identified relationships between nitrogen load from food consumption and driving factors by examining six representative countries and regions for the period 1970–2009 as an example. The logarithmic mean Divisia index technique was used to disassemble nitrogen load growth into four driving factors: population, economic activity, food intensity of the economy, and nitrogen content of food. In all study areas, increased economic activity was the main factor driving nitrogen load increase. The positive effect of population growth was relatively small but not negligible and changes in food intensity had a decreasing effect on nitrogen load. Changes in nitrogen content of food varied between areas. Broad strategies to reduce and mitigate nitrogen loading and decouple nitrogen load from economic growth in both developed and developing countries are suggested.  相似文献   
245.
Our objective was to examine how the behavior of atmospheric mercury (Hg) deposited to boreal lake mesocosms changed over time. We added inorganic Hg enriched in a different stable isotope in each of two years, which allowed us to differentiate between Hg added in the first and second year. Although inorganic Hg and methylmercury (MeHg) continued to accumulate in sediments throughout the experiment, the availability of MeHg to the food web declined within one year. This decrease was detected in periphyton, zooplankton, and water mites, but not in gomphid larvae, amphipods, or fish. We suggest that reductions in atmospheric Hg deposition should lead to decreases in MeHg concentrations in biota, but that changes will be more easily detected in short-lived pelagic species than long-lived species associated with benthic food webs.  相似文献   
246.
Even though petroleum-degrading microorganisms are widely distributed in soil and water, they may not be present in sufficient numbers to achieve contaminant remediation. In such cases, it may be useful to inoculate the polluted area with highly effective petroleum-degrading microbial strains to augment the exiting ones. In order to identify a microbial strain for bioaugmentation of oil-contaminated soil, we isolated a microbial strain with high emulsification and petroleum hydrocarbon degradation efficiency of diesel fuel in culture. The efficacy of the isolated microbial strain, identified as Candida catenulata CM1, was further evaluated during composting of a mixture containing 23% food waste and 77% diesel-contaminated soil including 2% (w/w) diesel. After 13 days of composting, 84% of the initial petroleum hydrocarbon was degraded in composting mixes containing a powdered form of CM1 (CM1-solid), compared with 48% of removal ratio in control reactor without inoculum. This finding suggests that CM1 is a viable microbial strain for bioremediation of oil-contaminated soil with food waste through composting processes.  相似文献   
247.
In the beginning, policy debates between critics and advocates of genetically modified (GM) crops focused on scientifically determined risks. Ten years later, the argument between environmentalists or consumers and regulators or industry has changed into a discussion about the implementation of more democratic policymaking about GM farming. A notable omission from the political debate about food biotechnology in the United States, however, is the opinion of farmers who cultivate the GM crops. Policymakers should value practical knowledge based on experiences from farmers, not only scientific industry reports or consumer product opinions. This project uses in-depth interviews to create an original mail survey that uses the practical discourse of farmers in order to explore the relationship of farmer attitudes and GM agriculture. Although national research indicates that larger yields are the most common reason for GM adoption, qualitative information suggest that the potential of GM crops to increase revenue per acre does not truly reflect all the concerns of modern farmers. For example, farmers who use GM seeds indicate that they constantly question the social impacts of their agricultural practices. As such, GM policies should be restructured as a political rationalization of both economic modeling and political theory because this research suggests that farmers’ business decisions are utility calucations that consider economics without ignoring environmental and political contexts. Farmers’ concerns about non-economic risks suggest that they need more information about GM crops and that governmental policies should respond to their interests, as they are more democratic or pluralistic than industry or consumer arguments.  相似文献   
248.
Between people who unabashedly support eating meat and those who adopt moral vegetarianism, lie a number of people who are uncomfortably carnivorous and vaguely wish they could be vegetarians. Opposing animal suffering in principle, they can ignore it in practice, relying on the visual disconnect between supermarket meat and slaughterhouse practices not to trigger their moral emotions. But what if we could have the best of both worlds in reality—eat meat and not harm animals? The nascent biotechnology of tissue culture, originally researched for medical applications, holds out just such a promise. Meat could be grown in vitro without killing animals. In fact, this technology may not just be an intriguing option, but might be our moral obligation to develop.  相似文献   
249.
Ecosystem-based management requires understanding of food webs. Consequently, assessment of food web status is mandatory according to the European Union’s Marine Strategy Framework Directive (MSFD) for EU Member States. However, how to best monitor and assess food webs in practise has proven a challenging question. Here, we review and assess the current status of food web indicators and food web models, and discuss whether the models can help addressing current shortcomings of indicator-based food web assessments, using the Baltic Sea as an example region. We show that although the MSFD food web assessment was designed to use food web indicators alone, they are currently poorly fit for the purpose, because they lack interconnectivity of trophic guilds. We then argue that the multiple food web models published for this region have a high potential to provide additional coherence to the definition of good environmental status, the evaluation of uncertainties, and estimates for unsampled indicator values, but we also identify current limitations that stand in the way of more formal implementation of this approach. We close with a discussion of which current models have the best capacity for this purpose in the Baltic Sea, and of the way forward towards the combination of measurable indicators and modelling approaches in food web assessments. Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01692-x.  相似文献   
250.
重庆市餐厨垃圾现状调查及处理对策研究   总被引:5,自引:0,他引:5  
唐敏  刘娇娇  唐燕秋  雷波 《四川环境》2010,29(1):136-139
本文采用问卷调查的方式,对重庆主城区的312家餐厨垃圾产生单位进行了抽样调查,了解餐厨垃圾的产生情况、排放去向、收运和处理现状,剖析了目前重庆市餐厨垃圾处置和管理中存在公众认知程度不够、相关法律法规不健全、收集处置不规范、市场机制尚未建立等主要问题,并提出了相关对策建议。  相似文献   
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