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561.
Raymond Anthony 《Journal of Agricultural and Environmental Ethics》2004,17(4-5):363-383
This paper offers some suggestions on, and encouragement for, how to be better at risk communication in times of agricultural crisis. During the foot and mouth epizootic, the British public, having no precedent to deal with such a rapid and widespread epizootic, no existing rules or conventions, and no social or political consensus, was forced to confront the facts of a perceived "economic disease. Foot and mouth appeared as an economic disease because the major push to eradicate it was motivated exclusively by trade and economic reasons and not because of threats it posed to the lives of human beings and livestock. The British public deferred responsibility to their elected officials for a speedy end to this non-life threatening viral epizootic. The latter, however, did not have a contingency plan in place to tackle such an extensive outbreak. The appeal to an existing policy, i.e., mass eradication, as the exclusive strategy of containment was a difficult pill for the public to swallow well before the end of the 226-day ordeal. Public outcry reflected (in part) serious misgivings about the lack of effective communication of risk-informed decisions between government agents and all concerned. The government's handling of the matter underestimated concerns and values about animal welfare, public trust, and the plight of farmers and rural communities. A general loss of trust by some segments of the public was exacerbated by perceived mismanagement and early fumbles by government agents.Public moral uneasiness during the crisis, while perhaps symbolic of growing discontent with an already fractured relationship with farmed animals and the state of animal farming today, arguably, also reflected deep disappointment in government agents to recognize inherently and conditionally normative assumptions in their argument as well as recognize their narrow conception of risk. Furthermore, broader stakeholder participation was clearly missing from the outset, especially with respect to the issue of vaccination. A greater appreciation for two-way risk communication is suggested for science-based public policy in agriculture, followed by suggestions on how to be more vigilant in the future. 相似文献
562.
Katinka?WaelbersEmail author Frans?Stafleu Frans?W.?A.?Brom 《Journal of Agricultural and Environmental Ethics》2004,17(6):497-515
The Netherlands is a small country with many people and much livestock. As a result, animals in nature reservations are often living near cattle farms. Therefore, people from the agricultural practices are afraid that wild animals will infect domestic livestock with diseases like Swine Fever and Foot and Mouth Disease. To protect agriculture (considered as an important economic practice), very strict regulations have been made for minimizing this risk. In this way, the practice of animal farming has been dominating the practices of nature management completely. If, for instance, Foot and Mouth Disease strikes an agricultural area, all wild pigs and cattle living in the nearby nature reservations have to be killed, whether infected or not. This dominant position of one practice over the other has now become problematic. While the morality of the practice of nature management seems to be very different from the morality of agriculture and agriculture has become less important from an economic point of view, the public as well as those involved in nature management no longer seem to accept the dominant position of agriculture. Besides a literature study, we performed a field study with in-depth interviews with experts from both practices to analyze the dynamics of the internal moralities of both practices in the previous century, in order to clarify the contemporary situation. The conclusion was that the traditionally strong position of agriculture is not only weakening; it also appears that the internal values of agriculture are changing. The experts from both sides agreed that, in case of a disease outbreak, it is neither ethically justified nor necessary (because of the estimated low risk of disease transfer) to destroy the animals in nature reservations as a routine preventive measure. This is a major shift in morality. 相似文献
563.
Shrimp exports are one of Sri Lanka's major foreign exchange earners and account for 40%–50% of total aquaculture exports.
There has been a recent and rapid expansion of the industry in the Northwestern Province (NWP) of Sri Lanka but the industry
has suffered from disease outbreaks and environmental problems. Currently, shrimp farms cover nearly 3000 ha of the coastal
area of the NWP.
The environmental impacts of shrimp cultivation in general are well known and numerous research studies have been done. However,
little work has been carried out in Sri Lanka. This study provides some necessary background to brackish water shrimp aquaculture
in Sri Lanka. It focuses briefly on the development of shrimp aquaculture and the current status of the industry. Emphasis
is placed on two broader aspects—impacts on the existing wetland ecosystem and on the environment. These impacts are presumed
to be the main causes hindering the growth of the industry and raising widespread public protest. Current ecosystem and environmental
management practices are discussed. Finally, strategic issues for management and sustainable growth are discussed. 相似文献
564.
一种分析城市代谢系统互动关系的方法 总被引:4,自引:0,他引:4
提出一种集成了能值分析和生态网络分析,研究城市代谢系统组分间互动关系的方法.基于城市复合生态系统和城市代谢的基本原理,在确定城市系统代谢单元和代谢环节的基础上,采用提出的方法,分析了城市代谢单元之间掠夺、限制和共生的关系.最后,以中国北京、上海、天津、重庆、广州和深圳6大城市为例进行了实证研究.结果表明,天津、重庆、广州市社会经济子系统对自然生态子系统存在着掠夺关系;北京、上海和深圳市自然生态子系统对社会经济子系统存在着限制关系;实现城市代谢系统良性运行的前提在于调控代谢单元间的互动关系,促进城市代谢单元间的协调共生. 相似文献
565.
566.
Stéphane M. McLachlan Melisa Yestrau 《Mitigation and Adaptation Strategies for Global Change》2009,14(4):299-316
Bovine spongiform encephalopathy (BSE) has been documented in 28 countries and adversely affected farmers and rural communities
around the world. Our study examines the impacts of and adaptive responses of producers to BSE in western Canada. Moreover,
it explores the role that holistic management (HM), and its combined focus on environmental, social, and economic sustainability,
might play in mitigating the effects of BSE. One survey was sent to 835 HM producers and another to 9,740 producers across
Manitoba, Saskatchewan, and Alberta. The disease, and concomitant climate change and low commodity prices, had devastating
impacts on both groups. Yet, HM producers were much more optimistic about their ability to adapt to BSE and the future of
agriculture than their non-HM counterparts. Social networks, namely HM clubs and the larger HM community, enabled these producers
to mitigate the impacts of BSE. Agronomic responses, especially those associated with rotational grazing and increases in
on-farm biodiversity were also important. That HM has been such an effective adaptive response to BSE indicates the importance
of this and other grassroots responses to rural crises, whether they be associated with zoonotic diseases or indeed environmental
change as a whole. 相似文献
567.
C/N对污泥厌氧发酵产酸类型及代谢途径的影响 总被引:3,自引:2,他引:1
研究了污泥的初始C/N对污泥发酵产酸类型的影响及产酸代谢途径.初始C/N在12时,形成的是乙酸型发酵类型;当初始C/N在56左右,可实现丙酸型发酵类型;而当C/N处于156时,则形成丁酸型发酵.不同发酵产酸类型的形成是由优势产酸菌群的改变导致的.末端限制性片段长度多态性分析(T-RFLP)微生物种群的结果表明,构成乙酸型发酵类型的主要优势菌群为消化链球菌属;而丙酸型发酵类型中的优势菌群则为丙酸杆菌属;梭菌属则是丁酸型发酵类型中的优势产酸功能菌.有机酸代谢途径中关键酶活性检测结果表明,在低C/N条件下,乙酸的累积主要是通过氨基酸之间的Stickland反应形成,而随着C/N值的增大,导致丙酸和丁酸累积的主要代谢途径转变为糖酵解的丙酮酸途径. 相似文献
568.
研究了2株多氯代二苯并二噁英高效降解白腐菌Phlebia lindtneri及Phlebia brevispora对氯丹的降解能力.在2个不同的液体培养体系中,2菌株对于高浓度(25μmol/L)的反式氯丹展现了较高的代谢能力,经6周培养后其降解率均达到50%以上.用GC/MS对其降解产物分析表明,氯丹的降解存在脱氢,脱氯化氢,羟基化以及氯原子的羟基置换4条不同的初始降解途径,除七氯,环氧七氯及氧化氯丹等常见初始代谢产物外,还发现3-羟基氯丹,氯代六氯醇,七氯二醇,羟基六氯,二羟基六氯等大量的羟基化代谢产物.尤其是P. lindtneri可以将曾被认为是终端代谢产物的氧化氯丹进行降解,并通过氯原子的羟基置换作用将其转化成羟基化代谢产物. 相似文献
569.
尖孢镰刀菌致病相关因子及其分子生物学研究进展 总被引:2,自引:0,他引:2
由致病性尖孢镰刀菌(Fusarium oxysporum)侵染引起的植物枯萎病是一种世界性的土传真菌病害,对农业生产造成了巨大经济损失.研究表明,尖孢镰刀菌的致病与多种致病因子相关,包括信号传导系统(环腺苷酸单磷酸-蛋白激酶A和促分裂素原活化蛋白激酶信号途径)、细胞壁降解酶(木聚糖酶、果胶酶、果胶裂解酶、细胞毒素、纤维素酶、半纤维素酶和木质素降解酶等)、克服植物防御响应系统(降解抗真菌化合物和破坏植物细胞壁的化学修饰)以及其它(细胞毒素和过氧化物酶)等.此外对今后的研究工作提出展望.参26 相似文献
570.