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241.
本文通过回顾我省30多年来地震监测台网的建设与发展以及地震监测数字化观测系统的发展历程,阐明了在新形势下如何进一步推进地震监测发展的思考,提出了新的观点和讨论的问题,以此促进我省地震监测工作的不断发展。 相似文献
242.
Evidence of an Edge Effect on Avian Nest Success 总被引:9,自引:0,他引:9
Abstract: Habitat fragmentation may modify ecological patterns by increasing the importance of edge effects, including elevating rates of predation on avian nests. Conventional wisdom suggests an increased rate of predation along habitat edges, and previous reviews support this view. These reviews did not apply recent statistical approaches, however, and some were based on a small number of studies. In our meta-analysis of 64 nest-predation experiments, our results supported prior reviews of the general pattern of increased nest predation along habitat edges ( p < 0.01). We separated studies into ecologically relevant categories and found the following patterns: (1) Edge effects were more pronounced in North America and northwestern Europe than in central Europe or Central America. This result may be biased, however, by the different habitats studied in the regions. (2) Marshes and deciduous forests had significant edge effects, whereas edge effects were not apparent in coniferous forests, tropical forests, or fields. (3) Ground and natural nest studies were more likely to exhibit edge effects. (4) Edge effects were detected in studies that used quail eggs and real eggs. (5) Edge effects were not significant when artificial nests were exposed for typical incubation periods, but were significant for shorter exposures. Three alternative hypotheses may explain increased nest predation along edges. The edge-effects hypothesis states that increased nest losses along edges are the result of the habitat discontinuity. The landscape-structure hypothesis states that more fragmented landscapes are more heavily depredated by nest predators. The human-disturbance hypothesis states that near anthropogenic edges increased nest predation is related to human activities. Nest-predation experiments should be placed in a landscape context to reveal differences between the hypotheses. 相似文献
243.
罗宁 《湖南环境生物职业技术学院学报》2005,11(3):247-250
本文对重症急性胰腺炎患者手术治疗的护理进展进行简要总结,以求对重症急性胰腺炎患者手术治疗中的护理工作提供参考. 相似文献
244.
Assessing Conservation Management's Evidence Base: a Survey of Management-Plan Compilers in the United Kingdom and Australia 总被引:2,自引:0,他引:2
Abstract: Conservation management is becoming increasingly resource intensive as threats to biodiversity grow through habitat destruction, habitat disturbance, and overexploitation. To achieve successful conservation and sustainable use of natural resources, we need to scientifically evaluate the effectiveness of conservation interventions and provide an efficient framework through which scientific evidence can be used to support decision making in policy and practice. We conducted the first formal assessment of the extent to which scientific evidence is used in conservation management through a questionnaire survey and follow-up interviews of compilers of protected-area management plans from major conservation organizations within the United Kingdom and Australia. Our survey results show that scientific information is not being used systematically to support decision making largely because it is not easily accessible to decision makers. This, in combination with limited monitoring and evaluation of effectiveness of management interventions, results in the majority of decisions being based on experience rather than on evidence. To address this problem we propose using an evidence-based framework adapted from that used in the health services and explain how we are currently putting an equivalent framework into practice by establishing review and dissemination units to serve the conservation sector. 相似文献
245.
The present review sets out to identify differences between refugees and other more stable communities living in less developed countries: demographic, mortality, morbidity, nutritional and selected epidemiological data are discussed. Although generalizations are difficult because of the variability of refugees and their differing circumstances, the health problems and diseases do not appear to differ qualitatively, although they may be quantitatively more severe.
The areas of particular concern lie not so much with the problems but with approaches to their solutions: the need to respond rapidly and appropriately to emergencies, the importance of attending to the priorities of nutrition, shelter, sanitation and water; and the necessity of providing services which are sufficiently flexible and sensitive to the changing needs of the refugees as they move from the acute emergency to the long-term settlements.
The review highlights certain areas where insufficient information is currently available, notably mental illness and the long-term issues of health and development, and outlines the implications of the conclusions for policy makers, with particular reference to training and research. 相似文献
The areas of particular concern lie not so much with the problems but with approaches to their solutions: the need to respond rapidly and appropriately to emergencies, the importance of attending to the priorities of nutrition, shelter, sanitation and water; and the necessity of providing services which are sufficiently flexible and sensitive to the changing needs of the refugees as they move from the acute emergency to the long-term settlements.
The review highlights certain areas where insufficient information is currently available, notably mental illness and the long-term issues of health and development, and outlines the implications of the conclusions for policy makers, with particular reference to training and research. 相似文献
246.
安全学科体系对引领我国安全学科发展和保持其应有地位具有十分重要的作用,从科学学的高度,运用安全科学学的思想,系统综述基于哲学-基础科学-应用科学分类的安全学科体系、基于上中下游三层次学科构成的安全学科体系等多种已形成的典型安全学科体系及其内涵,并提出建议和展望,以呼吁大家更加关注安全学科体系的协同发展。结果表明,安全学科体系的构建,应该尽量着眼于基于安全学科相对独立的基本概念群、研究对象、研究目的、研究范围,侧重于能够形成一套相对独立的安全科学理论、方法、模型、原理等;我国安全学科体系研究处于国际领先,基于科学层面构建和完善的安全学科体系,可引导安全学科快速发展,并使之成为世界范围认同的体系。 相似文献
247.
Preparation of starch esters 总被引:3,自引:0,他引:3
A review of starch esters prepared from either aqueous or solvent-based reactions leading to high (3.0)- and/or low (<0.2)-degree of substitution (DS) derivatives are discussed. A novel process for making intermediate-DS (0.5–1.8) starch esters from aqueous media is compared to traditional methods. 相似文献
248.
249.
Carmen Echebarria Jose M. Barrutia Ainhize Eletxigerra Patrick Hartmann Vanessa Apaolaza 《Journal of Environmental Planning and Management》2018,61(8):1289-1317
This article presents a systematic literature review of 109 articles (1992–2015) dealing with Local Agenda 21 processes worldwide. It analyzes two essential elements of Local Agenda 21: (1) the holistic approach of the sustainable development concept and (2) the main driving forces behind such processes. It shows that, although at the beginning, sustainability was seen as a natural extension of environmental policy work, it has been perceived over recent years as a guiding principle applied to issues of environment, economic development, and social welfare, and Local Agenda 21 is perceived as a coherent approach to sustainability planning. In addition, Local Government Strategy is the main typology followed, although it suffers from important limitations. Future studies could focus on local sustainability process outcomes. Further quantitative studies would be welcome, given the qualitative case study dominance in the field. We conclude with a research agenda to tackle theoretical, methodological, and empirical lacunae. 相似文献
250.