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191.
This study examines what happens when contentious lay citizens harness the technical-ecological repertoire of experts as means of challenging nature conservation policy. The causes, manifestations, and implications of this phenomenon are elucidated through a critical discourse analysis. The case study is based on the wolf reintroduction project in Europe, with particular focus on Sweden, using illegal hunting discussions as a point of entry within the hunting community. It reveals the deployment of three topoi, which are defined as stock arguments situated within a discourse. Analysis shows how while some topoi often incur short-term gains in the debate because of their scientific guise, they are fundamentally relegated as folk science (or “barstool biology”) by government experts and, in some cases, contribute to the further marginalization of other knowledges. Acquiescence to this discourse is shown to greatly impede the debate. Finally, the study shows how lack of trust in the public dialog, which hunters openly recognize to be colonized by ecological expertise, results in increasingly noncommunicative forms of resistance toward policy.  相似文献   
192.
Decisions about iconic species such as the wolf provide a key index of human–nature relations. The gray wolf's reintroduction in the USA has been controversial, particularly at the interface of state versus federal management. This essay analyzes discourse surrounding this controversy, focusing on how wolves are characterized as ecological and social actors in official correspondence and management plans. I interpret this textual evidence by drawing from social theory regarding sovereignty, discipline, and population, including studies on bordering practices imposed on humans. As with humans, bordering practices in the case of the wolf may illuminate how political forces impose physical and discursive limits upon mobile bodies motivated to move across political borders by powerful exigencies of need. The essay seeks to amplify understanding about how regimes of power enact difference from “others” whose presence strongly influences the health of ecosystems and economies.  相似文献   
193.
Planning researchers traditionally conceptualize learning as cognitive changes in individuals. In this tradition, scholars assess learning with pre- and post-measures of understandings or beliefs. While valuable for documenting individual change, such methods leave unexamined the social processes in which planners think, act, and learn in groups, which often involve the use of technical tools. The present interdisciplinary research program used Learning Sciences research methods, including conversation analysis, interaction analysis, and visualization of discourse codes, to understand how tools like agent-based models and geographic information systems mediate learning in planning groups. The objective was to understand how the use of these tools in participatory planning can help stakeholders learn about complex environmental problems, to make more informed judgments about the future. The paper provides three cases that illustrate the capacity of such research methods to provide insights into planning groups’ learning processes, and the mediating roles of planning tools.  相似文献   
194.
Multiple criteria evaluation (MCE) is often used with GIS to identify suitable sites for multi-purpose development such as ecotourism. Typically, expert or stakeholder consultation is used to identify weights reflecting the relative importance of map layers representing different criteria. The objective of this study was to evaluate a new consultative approach to GIS-based MCE, using ecotourism development in Kurdistan, Iraq, as a case study. In an initial and follow-up consultation, stakeholders were asked not only to assess the relative importance of different map layers for ecotourism development, but also to identify specific sites suitable for ecotourism. Seventy-eight ecotourism destinations nominated by participants had significantly higher MCE scores than a set of 58 locations chosen without reference to stakeholders (t-test = 21.16; p < 0.001). The approach thus provides a straightforward means of assessing the consistency of stakeholder input into MCE and could be adapted for use in other site suitability assessments.  相似文献   
195.
196.
为研究水分对低阶煤在堆积状态下自然发火特性的影响,基于Frank-Kamenetskii理论,采用开放式恒温加热试验法,分析不同水分含量(4%~23%)白音华褐煤的升温过程及临界自燃着火温度。进一步研究不同煤样粒径(0.5~5 mm)和煤堆体积(1.25~10×105 mm3)条件下,水分对堆积褐煤自燃特性的影响。结果表明,不同水分含量煤堆升温规律基本一致,根据中心点升温速率,可将煤样升温过程划分为4个动态阶段。相同粒径及体积条件下,水分含量越高,煤样临界自燃着火温度越高,抑制升温时间越长,表征内在水分蒸发强度的k值越大;相同水分及体积条件下,k值随粒径的增加呈现先增大后减小的趋势;相同水分及粒径条件下,煤堆体积越大,其临界自燃着火温度越低,水分的蒸发对不同体积煤堆自燃均表现出抑制作用。  相似文献   
197.
中国酸沉降:来源、影响与控制   总被引:4,自引:0,他引:4  
总结我国酸沉降观测与模拟、来源与影响以及控制与成效,不仅能为未来我国大气污染治理提供科学依据,也能为国际酸沉降控制提供参考.本文回顾了40年来我国酸沉降研究的发展历程,对有关酸雨时空分布特征、致酸气体排放、土壤和地表水酸化、酸化缓冲机制、临界负荷区划以及酸雨控制对策等研究进展进行综述.我国酸雨污染经历了快速发展、污染缓...  相似文献   
198.
This special issue of the Journal of Agricultural and Environmental Ethics presents so-called ethical tools that are developed to support systematic public deliberations about the ethical aspects of agricultural biotechnologies. This paper firstly clarifies the intended connotations of the term “ethical tools” and argues that such tools can support liberal democracies to cope with the issues that are raised by the application of genetic modification and other modern biotechnologies in agriculture and food production. The paper secondly characterizes the societal discussion on agricultural biotechnology and defends the thesis that normative perspectives fuel this discussion, so one cannot come to grips with this discussion if one neglects these perspectives. The paper thirdly agrues that no such thing exists as “one” societal debate in which these issues should be discussed. There are several interwined debates, and different actors participate in different discourses. Some practical instruments are necessary in order to include the right issues in these debates. These instruments will be coined as “ethical tools,” since they are practical instruments that can be used (tools) in order to support debates and deliberative structures for a systematic engagement with ethical issues (hence, ethical tools). Finally, the paper clarifies the ethics of these ethical tools and presents the tools as discussed in the remainder of this special issue: 1) tools to include ethical issues in public consulation and involvement; 2) tools to support systematic reflection upon ethical issues in decision-making; and 3) tools to support explicit communication about values in the food chain.  相似文献   
199.
根据全国195个气象台站10年的4次日记温度湿度数据统计了各站高于25℃和低于25℃的年润湿时间.研究了我国大陆地区温度超过25℃的年润湿时间所占比例的分布规律。研究表明:在我国大陆地区,25℃以上的年润湿时间所占比例很少高于50%,该比例是东部高于西部,南部高于北部,沿海高于内地。  相似文献   
200.
First flush of storm runoff pollution from an urban catchment in China   总被引:13,自引:0,他引:13  
Storm runoff pollution process was investigated in an urban catchment with an area of 1.3 km^2 in Wuhan City of China. The results indicate that the pollutant concentration peaks preceded the flow peaks in all of 8 monitored storm events. The intervals between pollution peak and flow peak were shorter in the rain events with higher intensity in the initial period than those with lower intensity. The fractions of pollution load transported by the first 30% of runoff volume (FF30) were 52.2%-72.1% for total suspended solids (TSS), 53.0%-65.3% for chemical oxygen demand (COD), 40.4%-50.6% for total nitrogen (TN), and 45.8%-63.2% for total phosphorus (TP), respectively. Runoff pollution was positively related to non-raining days before the rainfall. Intercepting the first 30% of runoff volume can remove 62.4% of TSS load, 59.4% of COD load, 46.8% of TN load, and 54.1% of TP load, respectively, according to all the storm events. It is suggested that controlling the first flush is a critical measure in reduction of urban stormwater pollution.  相似文献   
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