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251.
我国非煤矿山安全生产科技进展与科技需求分析   总被引:3,自引:1,他引:3  
在我国所称非煤矿山是指除去煤矿之外的所有矿山,包括露天矿山、地下矿山和联合开采矿山。近年来,我国针对非煤矿山安全重大科技问题开展了一些研究工作,科技投入有较大幅度增加,开展的国家“十一五”重点支撑项目“非煤矿山典型灾害防治关键技术研究与示范工程”等取得了一些成果。但是,非煤矿山的重大和特别重大生产安全事故发生频率仍处于较高水平,安全生产形势依然严峻,很多非煤矿山重大技术难题仍没有得到解决,急需研究适应我国非煤矿山特点的尾矿库安全技术、采空区治理技术、深井开采安全技术、高风险气田开发安全技术、自然灾害次生衍生生产安全事故预防技术等。  相似文献   
252.
为了解安全科技人员利用文献的特点和安全工程学科文献的发展规律,根据文献计量学分析理论与方法,对1995—2009年安全工程本科专业建设研究文献的发文量、文献著者、核心作者群、核心期刊群、引文文献、被引用情况和基金项目资助等进行分析研究,结果表明:安全工程本科专业建设研究的发文量较少但整体呈上升态势;文献著者的合作度为2.5,合著率76.1%,文献的合作度和合著率较低,研究深度和广度需进一步加强,同时需加强多单位联合研究;高校研究者是该领域的主力军,其发文量占92.5%,但核心作者群尚未形成;《中国安全科学学报》是该领域研究的核心期刊,北京是该领域研究的核心区域;期刊文献是主要的引文类型(73.5%),引文语种主要是中文文献(97.3%),篇均引文文献4.9篇,普赖斯指数较高(73.3%);文献的被引用频次整体较低(2.2);2005年以来文献的基金项目资助率为30.2%,基金项目资助率和资助项目级别均呈上升趋势。  相似文献   
253.
Abstract: Debate on the values that underpin conservation science is rarely based on empirical analysis of the values conservation professionals actually hold. We used Q methodology to investigate the values held by international conservation professionals who attended the annual Student Conference in Conservation Science at the University of Cambridge (U.K.) in 2008 and 2009. The methodology offers a quantitative means of examining human subjectivity. It differs from standard opinion surveys in that individual respondents record the way they feel about statements relative to other statements, which forces them to focus their attention on the issues they believe are most important. The analysis extracts the diverse viewpoints of the respondents, and factor analysis is used to reduce the viewpoints to a smaller set of factors that reflect shared ways of thinking. The junior conservation professionals attending the conference did not share a unifying set of core values; rather, they held a complex series of ideas and a plurality of opinions about conservation and how it should be pursued. This diversity of values empirically challenges recent proposals for conservation professionals to unite behind a single philosophy. Attempts to forge an artificial consensus may be counterproductive to the overall goals conservation professionals are pursuing.  相似文献   
254.
Abstract: Integrating knowledge from across the natural and social sciences is necessary to effectively address societal tradeoffs between human use of biological diversity and its preservation. Collaborative processes can change the ways decision makers think about scientific evidence, enhance levels of mutual trust and credibility, and advance the conservation policy discourse. Canada has responsibility for a large fraction of some major ecosystems, such as boreal forests, Arctic tundra, wetlands, and temperate and Arctic oceans. Stressors to biological diversity within these ecosystems arise from activities of the country's resource‐based economy, as well as external drivers of environmental change. Effective management is complicated by incongruence between ecological and political boundaries and conflicting perspectives on social and economic goals. Many knowledge gaps about stressors and their management might be reduced through targeted, timely research. We identify 40 questions that, if addressed or answered, would advance research that has a high probability of supporting development of effective policies and management strategies for species, ecosystems, and ecological processes in Canada. A total of 396 candidate questions drawn from natural and social science disciplines were contributed by individuals with diverse organizational affiliations. These were collaboratively winnowed to 40 by our team of collaborators. The questions emphasize understanding ecosystems, the effects and mitigation of climate change, coordinating governance and management efforts across multiple jurisdictions, and examining relations between conservation policy and the social and economic well‐being of Aboriginal peoples. The questions we identified provide potential links between evidence from the conservation sciences and formulation of policies for conservation and resource management. Our collaborative process of communication and engagement between scientists and decision makers for generating and prioritizing research questions at a national level could be a model for similar efforts beyond Canada.  相似文献   
255.
Biodiversity monitoring at large spatial and temporal scales is greatly needed in the context of global changes. Although insects are a species‐rich group and are important for ecosystem functioning, they have been largely neglected in conservation studies and policies, mainly due to technical and methodological constraints. Sound detection, a nondestructive method, is easily applied within a citizen‐science framework and could be an interesting solution for insect monitoring. However, it has not yet been tested at a large scale. We assessed the value of a citizen‐science program in which Orthoptera species (Tettigoniidae) were monitored acoustically along roads. We used Bayesian model‐averaging analyses to test whether we could detect widely known patterns of anthropogenic effects on insects, such as the negative effects of urbanization or intensive agriculture on Orthoptera populations and communities. We also examined site‐abundance correlations between years and estimated the biases in species detection to evaluate and improve the protocol. Urbanization and intensive agricultural landscapes negatively affected Orthoptera species richness, diversity, and abundance. This finding is consistent with results of previous studies of Orthoptera, vertebrates, carabids, and butterflies. The average mass of communities decreased as urbanization increased. The dispersal ability of communities increased as the percentage of agricultural land and, to a lesser extent, urban area increased. Despite changes in abundances over time, we found significant correlations between yearly abundances. We identified biases linked to the protocol (e.g., car speed or temperature) that can be accounted for ease in analyses. We argue that acoustic monitoring of Orthoptera along roads offers several advantages for assessing Orthoptera biodiversity at large spatial and temporal extents, particularly in a citizen science framework. El Uso de Monitoreos Acústicos a Gran Escala para Estudiar las Presiones Antropogénicas sobre Comunidades de Orthoptera  相似文献   
256.
There are many barriers to using science to inform conservation policy and practice. Conservation scientists wishing to produce management‐relevant science must balance this goal with the imperative of demonstrating novelty and rigor in their science. Decision makers seeking to make evidence‐based decisions must balance a desire for knowledge with the need to act despite uncertainty. Generating science that will effectively inform management decisions requires that the production of information (the components of knowledge) be salient (relevant and timely), credible (authoritative, believable, and trusted), and legitimate (developed via a process that considers the values and perspectives of all relevant actors) in the eyes of both researchers and decision makers. We perceive 3 key challenges for those hoping to generate conservation science that achieves all 3 of these information characteristics. First, scientific and management audiences can have contrasting perceptions about the salience of research. Second, the pursuit of scientific credibility can come at the cost of salience and legitimacy in the eyes of decision makers, and, third, different actors can have conflicting views about what constitutes legitimate information. We highlight 4 institutional frameworks that can facilitate science that will inform management: boundary organizations (environmental organizations that span the boundary between science and management), research scientists embedded in resource management agencies, formal links between decision makers and scientists at research‐focused institutions, and training programs for conservation professionals. Although these are not the only approaches to generating boundary‐spanning science, nor are they mutually exclusive, they provide mechanisms for promoting communication, translation, and mediation across the knowledge–action boundary. We believe that despite the challenges, conservation science should strive to be a boundary science, which both advances scientific understanding and contributes to decision making. Logrando que la Ciencia de la Conservación Trasponga la Frontera Conocimiento‐Acción  相似文献   
257.
A vast number of prioritization schemes have been developed to help conservation navigate tough decisions about the allocation of finite resources. However, the application of quantitative approaches to setting priorities in conservation frequently includes mistakes that can undermine their authors’ intention to be more rigorous and scientific in the way priorities are established and resources allocated. Drawing on well‐established principles of decision science, we highlight 6 mistakes commonly associated with setting priorities for conservation: not acknowledging conservation plans are prioritizations; trying to solve an ill‐defined problem; not prioritizing actions; arbitrariness; hidden value judgments; and not acknowledging risk of failure. We explain these mistakes and offer a path to help conservation planners avoid making the same mistakes in future prioritizations. Seis Errores Comunes en la Definición de Prioridades de Conservación  相似文献   
258.
毒死蜱在香蕉、土壤中的残留动态及安全性评价   总被引:2,自引:0,他引:2  
为了监测香蕉中毒死蜱的残留量,科学、安全地使用毒死蜱防治香蕉上的害虫,确保产品质量,采用气相色谱法及田间试验方法,研究了毒死蜱在香蕉及其土壤中的残留降解动态.结果表明:在香蕉中,毒死蜱的原始沉积量较高,残留降解规律符合一级动力学关系,推荐剂量和加倍剂量处理的降解动态方程分别为y=1.0724e-014149t和y=1.7840e-0.1468t,半衰期(T1/2)为4.8 d,降解99%所需要的时间(T0.99)为31.4~31.8d;在土壤中,毒死蜱的残留降解动态方程为y=6.4365e-1412t,T1/2为4.9d,T0.99为32.7 d.距第2次施药后60~68d,最终在香蕉与土壤中均未检出毒死蜱残留量(检出限为0.005mg/kg).研究表明,漳州蕉区在香蕉生产上科学、合理地施用毒死蜱,其最终残留符合NY/T 750-2011规定的MRL要求,不会对蕉园土壤环境造成污染.  相似文献   
259.
We considered a series of conservation-related research projects on the island of Pemba, Tanzania, to reflect on the broad significance of Beier et al.’s recommendations for linking conservation science with practical conservation outcomes. The implementation of just some of their suggestions can advance a successful coproduction of actionable science by small research teams. Key elements include, first, scientists and managers working together in the field to ensure feedback in real time; second, questions jointly identified by managers and researchers to facilitate engaged collaboration; third, conducting research at multiple sites, thereby broadening managers’ abilities to reach multiple stakeholders; and fourth, establishing a multidisciplinary team because most of the concerns of local managers require input from multiple disciplines.  相似文献   
260.
水分管理方式对水稻在Cd污染土壤上生长及其吸收Cd的影响   总被引:14,自引:0,他引:14  
通过水稻盆栽试验,研究了Cd污染土壤上旱作、不同生育期烤田和全生育期淹水等不同水分管理方式对水稻生长及其吸收Cd的影响.结果表明,旱作栽培对水稻生长发育影响较大,水稻产量较低,与全生育期淹水栽培相比,产量下降了28.74%.全生育期淹水栽培具有一定的产量水平,但不是最高,分蘖期和灌浆期烤田比其产量提高14.58%和10.27%.在全生育期淹水栽培方式下,水稻糙米中Cd含量最低,旱作和不同生育期烤田,水稻籽粒中Cd的含量会增加,其中水稻旱作的增加最多,达166.31%,而灌浆乳熟期增加较少.研究表明,被Cd在一定程度上污染的土壤上种植水稻,采用旱作方式应慎重,以避免水稻旱作所带来的粮食品质的安全风险.  相似文献   
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