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241.
Conservation professionals recognize the need to evaluate education initiatives with a flexible approach that is culturally appropriate. Cultural‐consensus theory (CCT) provides a framework for measuring the extent to which beliefs are communally held and has long been applied by social scientists. In a conservation‐education context, we applied CCT and used free lists (i.e., a list of items on a topic stated in order of cultural importance) and domain analysis (analysis of how free lists go together within a cultural group) to evaluate a conservation education program in which we used a children's picture book to increase knowledge about and empathy for a critically endangered mammal, the Javan slow loris (Nycticebus javanicus). We extracted free lists of keywords generated by students (n = 580 in 18 schools) from essays they wrote before and after the education program. In 2 classroom sessions conducted approximately 18 weeks apart, we asked students to write an essay about their knowledge of the target species and then presented a book and several activities about slow loris ecology. Prior to the second session, we asked students to write a second essay. We generated free lists from both essays, quantified salience of terms used, and conducted minimal residuals factor analysis to determine presence of cultural domains surrounding slow lorises in each session. Students increased their use of words accurately associated with slow loris ecology and conservation from 43% in initial essays to 76% in final essays. Domain coherence increased from 22% to 47% across schools. Fifteen factors contributed to the domain slow loris. Between the first and second essays, factors that showed the greatest change were feeding ecology and slow loris as a forest protector, which increased 7‐fold, and the humancentric factor, which decreased 5‐fold. As demonstrated by knowledge retention and creation of unique stories and conservation opinions, children achieved all six levels of Bloom's taxonomy of learning domains. Free from the constraints of questionnaires and surveys, CCT methods provide a promising avenue to evaluate conservation education programs.  相似文献   
242.
Although deforestation and forest degradation have long been considered the most significant threats to tropical biodiversity, across Southeast Asia (Northeast India, Indochina, Sundaland, Philippines) substantial areas of natural habitat have few wild animals (>1 kg), bar a few hunting‐tolerant species. To document hunting impacts on vertebrate populations regionally, we conducted an extensive literature review, including papers in local journals and reports of governmental and nongovernmental agencies. Evidence from multiple sites indicated animal populations declined precipitously across the region since approximately 1980, and many species are now extirpated from substantial portions of their former ranges. Hunting is by far the greatest immediate threat to the survival of most of the region's endangered vertebrates. Causes of recent overhunting include improved access to forests and markets, improved hunting technology, and escalating demand for wild meat, wildlife‐derived medicinal products, and wild animals as pets. Although hunters often take common species, such as pigs or rats, for their own consumption, they take rarer species opportunistically and sell surplus meat and commercially valuable products. There is also widespread targeted hunting of high‐value species. Consequently, as currently practiced, hunting cannot be considered sustainable anywhere in the region, and in most places enforcement of protected‐area and protected‐species legislation is weak. The international community's focus on cross‐border trade fails to address overexploitation of wildlife because hunting and the sale of wild meat is largely a local issue and most of the harvest is consumed in villages, rural towns, and nearby cities. In addition to improved enforcement, efforts to engage hunters and manage wildlife populations through sustainable hunting practices are urgently needed. Unless there is a step change in efforts to reduce wildlife exploitation to sustainable levels, the region will likely lose most of its iconic species, and many others besides, within the next few years.  相似文献   
243.
A key controversy in conservation is the framing of the relationship between people and nature. The extent to which the realms of nature and human culture are viewed as separate (dualistic view) or integrated is often discussed in the social sciences. To explore how this relationship is represented in the practice of conservation in Europe, we considered examples of cultural landscapes, wildlife (red deer, reindeer, horses), and protected area management. We found little support, for a dualistic worldview, where people and nature are regarded as separate in the traditional practice of conservation in Europe. The borders between nature and culture, wild and domestic, public land and private land, and between protected areas and the wider landscape were blurred and dynamic. The institutionalized (in practice and legislation) view is of an interactive mutualistic system in which humans and nature share the whole landscape. However, more dualistic ideals, such as wilderness and rewilding that are challenging established practices are expanding. In the context of modern day Europe, wilderness conservation and rewilding are not valid for the whole landscape, although it is possible to integrate some areas of low‐intervention management into a wider matrix. A precondition for success is to recognize and plan for a plurality of values concerning the most valid approaches to conservation and to plan for this plurality at the landscape scale.  相似文献   
244.
Ramp‐up or soft‐start procedures (i.e., gradual increase in the source level) are used to mitigate the effect of sonar sound on marine mammals, although no one to date has tested whether ramp‐up procedures are effective at reducing the effect of sound on marine mammals. We investigated the effectiveness of ramp‐up procedures in reducing the area within which changes in hearing thresholds can occur. We modeled the level of sound killer whales (Orcinus orca) were exposed to from a generic sonar operation preceded by different ramp‐up schemes. In our model, ramp‐up procedures reduced the risk of killer whales receiving sounds of sufficient intensity to affect their hearing. The effectiveness of the ramp‐up procedure depended strongly on the assumed response threshold and differed with ramp‐up duration, although extending the duration of the ramp up beyond 5 min did not add much to its predicted mitigating effect. The main factors that limited effectiveness of ramp up in a typical antisubmarine warfare scenario were high source level, rapid moving sonar source, and long silences between consecutive sonar transmissions. Our exposure modeling approach can be used to evaluate and optimize mitigation procedures. Modelado de la Efectividad de los Incrementos Graduales en el Nivel de la Fuente para Mitigar Efectos de Sonar sobre Mamíferos Marinos  相似文献   
245.
主要介绍了在国家外排粉尘浓度标准日益严格,普通电除尘器很难达标的背景下,提高电除尘器过滤效率的一种新技术软稳电除尘技术的原理和应用。  相似文献   
246.
煤矿软岩巷道支护问题是制约煤矿安全高效生产的技术难题之一,在不同形式的地下水影响下,巷道支护难度急剧增加。为了研究水岩耦合作用对软岩巷道变形的影响规律,基于FLAC3D数值模拟方法对变孔隙水压力作用下软岩巷道围岩位移场和应力场演化规律进行了仿真研究。结果表明,孔隙水压力对软岩巷道的稳定性具有显著影响,且孔隙水压力的演化趋势与应力场演化特征具有同步性。在巷道围岩均布孔隙水压力的条件下,孔隙水压力对两帮的影响范围大于顶底板,圆拱形巷道弧顶正上方1.435~4.21 m范围内应力集中程度可达到原孔隙水压力的3.09~4.03倍,逐渐向外围扩展为扇形面的孔隙压力等值区域,在巷道的下方孔隙水压力呈"W"形分界面。  相似文献   
247.
Autoinducer 2(AI-2), an important bioactive by-product of the Lux S-catalyzed S-ribosylhomocysteine cleavage reaction in the activated-methyl-cycle, has been suggested to serve as a universal intra- and inter-species signaling molecule. The development of reliable and sensitive methods for quantitative determination of AI-2 is highly desired.However, the chemical properties of AI-2 cause difficulty in its quantitative analysis.Herein, we report a high performance liquid chromatography-tandem mass spectrometric method that enables reproducible and sensitive measurement of AI-2 concentrations in complex matrixes. 4,5-Dimethylbenzene-1,2-diamine(DMBDM), an easy-to-obtain commercial reagent, was used for the derivatization treatment. The assay was linear in the concentration range of 1.0–1000 ng/m L(R~2= 0.999) and had a lower limit of quantification of0.58 ng/m L. The method exhibited several advantages, e.g., high selectivity, wide linear response range, and good sensitivity. Furthermore, the effectiveness of the method was further validated through measuring AI-2 concentrations in the cell-free culture supernatant from Escherichia coli wild type.  相似文献   
248.
为解决土城煤矿14运输上山软岩巷道变形量大、锚杆索失效严重等技术难题,通过现场调研、室内试验、理论分析、数值模拟及工业性试验等方法,揭示了围岩变形特征以及巷道失稳破坏机理,提出了“三壳”围岩控制理论。基于以上研究,设计了“锚杆锚索+灌浆+钢管混凝土支架”的复合支护方案,建立了基于“三壳”围岩控制理论的“三壳”支护结构体力学模型,计算出设计方案的极限承载能力为2.54 MPa,随后采用 FLAC3D数值模拟软件对设计方案进行模拟分析,验证了方案合理性。最后,该复合支护得到成功运用,现场监测结果表明:巷道顶底板以及两帮变形量均低于100 mm,巷道未发生明显变形,支护效果良好。  相似文献   
249.
给出了开发铝筒拉深模参数化计算机辅助设计软件的思路。应用该软件 ,可以通过人机对话方式输入铝筒的相关参数 ,自动完成铝筒拉深模的理论计算和绘图。显著提高了设计质量和效率。  相似文献   
250.
福建武夷山自然保护区野生经济植物资源   总被引:4,自引:1,他引:4  
笔者在多年调查研究的基础上,统计了武夷山自然保护区维管束植物有 194科、851 属、2025种、80亚种(或变种),并分析了各属的区系成分。在此基础上,根据野生经济植物的用途,把区内野生经济植物分为 8类:即油脂植物、淀粉及糖类植物、芳香油植物、纤维植物、鞣料植物、观赏植物、药用植物、蜜粉源植物,论述了各类野生经济植物的主要种类,为进一步研究武夷山自然保护区野生经济植物,以及植物资源的合理利用与保护提供基础资料和有关的科学依据。  相似文献   
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