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791.
Local food networks (LFNs) are growing in popularity, in part as a response to broader criticisms of conventional food production. Municipal policy-makers have the opportunity to work with stakeholders to build LFNs to increase access to healthy foods in cities and ultimately improve population health and well-being. Building opportunities for healthy eating is particularly important in our study area. Flint, Michigan, is a post-industrial shrinking city suffering from the economic and health effects of deindustrialisation. Various stakeholders in Flint have responded to a significant issue with access to food by strengthening collaborations through a food policy council (FPC). Growth in the local food system has been supported by administrators and community advocates alike, through supporting community gardens, farmers' markets, and urban agriculture in a manner similar to nearby Detroit. Participant observation was conducted with stakeholders involved in the development of the LFN and the FPC in Flint. Stakeholders were exposed to existing research on the food system to help inform their policy direction. The group expressed several core concerns and prospects for future work, including a strong emphasis on consensus-based decision-making. Based on the synthesis of stakeholder opinions, policy recommendations are made to aid in continued planning of the LFN. Planning for food is an important first step in improving public health and strengthening local economic development in post-industrial cities. This research highlights the issue by making explicit the challenges and opportunities for policy advocacy in LFNs. 相似文献
792.
793.
Land take and food security: assessment of land take on the agricultural production in Europe 总被引:1,自引:0,他引:1
Ciro Gardi Panos Panagos Marc Van Liedekerke Claudio Bosco Delphine De Brogniez 《Journal of Environmental Planning and Management》2015,58(5):898-912
Soil is a multifunctional, non-renewable natural resource for Europe as clearly expressed in the European Union (EU) Thematic Strategy for Soil Protection (COM (2006)231). Soil carries out multiple functions, including the support of food production. Urban development and its associated land take poses a major threat to soil and could have significant effects on agricultural production. This paper aims to evaluate the potential productivity losses in European agriculture due to land-take processes between 1990 and 2006. Agricultural land take was calculated using CORINE Land Cover maps of 1990, 2000 and 2006. For 21 of the 27 EU member states, agricultural land take was computed to be 752,973 ha for 1990–2000 and 436,095 ha for 2000–2006, representing 70.8% and 53.5%, respectively, of the total EU land take for these periods. The impact of this land take on the production capabilities of the agricultural sector for the period 1990–2006 for 19 of the 21 states was estimated to be equivalent to a loss of more than six million tonnes of wheat. The paper demonstrates that Europe's intense urbanisation has a direct impact on its capability to produce food. 相似文献
794.
微生物分子生态学进展[综述] 总被引:2,自引:2,他引:0
现代分子生物学技术在生态学研究中的应用大大推动了微生物生态学的发展,导致了微生物分子生态学的产生.微生物分子生态学方法弥补了传统的微生物生态学方法的不足,使人们可以避开传统的分离培养过程而直接探讨自然界中微生物的种群结构及其与环境的关系.微生物生态学研究中采用的分子生物学方法主要有核酸探针技术、PCR扩增技术、rRNA序列同源性分析方法、剃度凝胶电泳方法等.这些技术方法的采用,取得了一系列重要的成果和微生物生态学研究中的突破[1~6],使得对某些微生物的研究成为可能,并在分子水平上阐述了生态问题… 相似文献
795.
微生物分子生态学进展 总被引:2,自引:0,他引:2
《应用与环境生物学报》1999,5(Z1):1000
This paper summarizes some molecular
techniques applied in the studies on microbial ecology,such as hybridization of nucleic
acid probes,ampification of polymerase chain reaction,denaturing gradient gel
electrophoresis and analyses of ribosomal RNA gene sequences,and the progress,performance,achievements
and advances made from the researches of microbial ecology in recent years by using these
molecular techniques. 相似文献
796.
陈筱 《生态与农村环境学报》1999,(4)
分析了神农架建设绿色食品基地的自然优势条件和农业资源特点,提出了发展山区、河谷、城镇基地,创建名牌资源品种的建设方针。 相似文献
797.
基于建筑全生命周期这个主线,建筑可持续发展视角下供应链协调与社会责任共担机理研究,以绿色建筑供应链运行效率为导向,以既有建筑节能改造效率为切入点,以产业链过程中各主体行为规律为基础,采用“总-分-合”的基本研究思路模式,聚焦了“主导企业驱动下绿色建筑供应链协调机理与策略、既有建筑节能改造主体社会责任共担机理、建筑废弃物再生利用产业链主体社会责任共担机理”等三部分核心内容,初步形成建筑可持续发展视角下供应链协调与社会责任共担机理的理论体系。本成果采用“总-分-合”的思路模式,基于循环经济理念和主体行为策略视角,遵循研究的学理逻辑,以研究生学位论文为基础,开展“主导企业驱动下绿色建筑供应链协调机理与策略、既有建筑节能改造主体社会责任共担机理、建筑废弃物再生利用产业链主体社会责任共担机理”3个子课题研究,从系统整体概况实施全面研究规划着手,构架了总括、绿色建筑供应链协调机理、既有建筑节能改造主体社会责任共担、建筑废弃物再生利用社会责任共担、总结等五大模块及上中下三大篇共12章的系统体系。 相似文献
798.
Frans W. A. Brom 《Journal of Agricultural and Environmental Ethics》2000,12(2):127-139
The use of biotechnology in food productiongives rise to consumer concerns. The term ``consumerconcern' is often used as a container notion. Itincludes concerns about food safety, environmental andanimal welfare consequences of food productionsystems, and intrinsic moral objections againstgenetic modification. In order to create clarity adistinction between three different kinds of consumerconcern is proposed. Consumer concerns can be seen assigns of loss of trust. Maintaining consumer trustasks for governmental action. Towards consumerconcerns, governments seem to have limitedpossibilities for public policy. Under current WTOregulations designed to prevent trade disputes,governments can only limit their policies to 1) safetyregulation based upon sound scientific evidence and 2)the stimulation of a system of product labeling. Ananalysis of trust, however, can show that ifgovernments limit their efforts in this way, they willnot do enough to avoid the types of consumer concernsthat diminish trust. The establishment of a technicalbody for food safety – although perhaps necessary –is in itself not enough, because concerns that relatedirectly to food safety cannot be solved by ``pure'science alone. And labeling can only be a good way totake consumer concerns seriously if these concerns arerelated to consumer autonomy. For consumer concernsthat are linked to ideas about a good society,labeling can only provide a solution if it is seen asan addition to political action rather than as itssubstitution. Labeling can help consumers take uptheir political responsibility. As citizens, consumershave certain reasonable concerns that can justifiableinfluence the market. In a free-market society, theyare, as buyers, co-creators of the market, andsocietal steering is partly done by the market.Therefore, they need the information to co-create thatmarket. The basis of labeling in these cases, however,is not the good life of the individual but thepolitical responsibility people have in their role asparticipants in a free-market. Then, public concernsare taken seriously. Labeling in that case does nottake away the possibilities of reaching politicalgoals, but it adds a possibility. 相似文献
799.
Terry Newholm 《Journal of Agricultural and Environmental Ethics》2000,12(2):153-164
Disputes over agriculture and foodproduction have occurred against a background ofdisputed authority with regard to governments,experts, and single issue pressure groups. Consumershave intervened in quite significant ways with manyaltering their buying patterns. The conventionalassessment of consumer ``preferences' throughaggregated purchases fails to reflect the ethicalnature of significant numbers of purchase decisions.Nevertheless, consumers seem to offer a wider basis onwhich to consider ethical issues. The author proposesthat a valuable inclusion of consumer opinion in thedebates would require a move away from neo-classicaleconomics and the selective inclusion of consumeropinion to unravel the complexity of (aggregated)consumer behavior. It is argued that Hirschman'sframework of ``exit, voice, and loyalty' is a moreappropriate tool for the understanding of ethics infood consumption. 相似文献
800.
以系统降解效能和产甲烷量最大化为目标,分别考察不同有机负荷(8.93、10.71、13.39 kg·m-3·d-1)及进料频率(1、2、3次·d-1)下厨余垃圾中温厌氧消化系统运行过程中甲烷产量、SCOD、氨氮、pH和挥发性脂肪酸(VFAs)的变化,旨在明确系统负荷边界及进料频率对系统稳定性的影响.结果表明,系统的有机负荷存在最优值,系统累计产甲烷量随负荷的增加而升高,随后降低,有机负荷为10.71 kg·m-3·d-1时获得最大累计产甲烷量37.17 L,VS降解率72.58%.负荷增加系统稳定性下降甚至失稳,各物质出现积累,不利于反应的进行.增加进料频率可优化系统运行参数,显著提高系统产气和产甲烷量,进料频率较高时,运行周期内系统的甲烷产量及产率最高,分别达到45.03 L和0.738 L·g-1,呈线性增长,增加进料频率可提高系统对氨氮的耐受能力,显著提高系统稳定性,明显改善VFA和丙酸积累问题. 相似文献