遥感在生态与环境监测中的主要应用领域

遥感是一种以物理手段、数学方法和地学分析为基础的综合应用技术 ,具有宏观、综合、动态和快速的特点。在解决宏观尺度的环境问题时 ,卫星遥感可重复获取多种空间、不同时相和不同波谱分辨率的地球信息 ,是适宜于调查和研究这些主题的唯一的、最有效的工具。本文通过对遥感在环境与生态监测的主要应用领域进行概要阐述 ,旨在抛砖引玉 ,推动遥感在环境与生态监测中的广泛应用。     

基于上海案例的大都市旅游容量及承载力研究

都市旅游容量和承载力问题是事关都市旅游可持续发展、和谐旅游环境建设的重大战略性命题。上海都市旅游发展跨入了由数量扩张向质量提升的重要转型发展期。面临警旅游容量问题的严峻挑战。都市旅游容量管理与调控是一项社会系统工程。实施旅游容量管理与调控不是剥夺或限制公民进入都市旅游和体验的权利。而是根据这种区域的极限容量阀值。疏导进入大都市的旅游流。使之保持警一种合理的、持续的容量态势发展，维系整个区域发展的可持续性。为此。要创新都市旅游容量与承载力管理的制度安排。通过都市旅游产品转型与创新、基础设施技术升级和扩能、都市旅游布局空间战略调整、区域协调与联动、实施旅游可持续指标行动等举措，进一步释放都市旅游容量及承载力潜力，缓解都市中心城区容量压力。促进都市旅游可持续发展。     

焦化苯初馏份蒸馏釜发生爆炸的原因探讨

通过对某企业的一起典型爆炸事故案例进行分析,找出其产生的原因,提出了预防措施。     

Decision‐Making Triggers in Adaptive Management

We analyzed whether decision‐making triggers increase accountability of adaptive‐management plans. Triggers are prenegotiated commitments in an adaptive‐management plan that specify what actions are to be taken and when on the basis of information obtained from monitoring. Triggers improve certainty that particular actions will be taken by agencies in the future. We conducted an in‐depth, qualitative review of the political and legal contexts of adaptive management and its application by U.S. federal agencies. Agencies must satisfy the judiciary that adaptive‐management plans meet substantive legal standards and comply with the U.S. National Environmental Policy Act. We examined 3 cases in which triggers were used in adaptive‐management plans: salmon (Oncorhynchus spp.) in the Columbia River, oil and gas development by the Bureau of Land Management, and a habitat conservation plan under the U.S. Endangered Species Act. In all the cases, key aspects of adaptive management, including controls and preidentified feedback loops, were not incorporated in the plans. Monitoring and triggered mitigation actions were limited in their enforceability, which was contingent on several factors, including which laws applied in each case and the degree of specificity in how triggers were written into plans. Other controversial aspects of these plans revolved around who designed, conducted, interpreted, and funded monitoring programs. Additional contentious issues were the level of precaution associated with trigger mechanisms and the definition of ecological baselines used as points of comparison. Despite these challenges, triggers can be used to increase accountability, by predefining points at which an adaptive management plan will be revisited and reevaluated, and thus improve the application of adaptive management in its complicated political and legal context. Detonadores de la Toma de Decisiones en el Manejo Adaptativo     

世界旅游精品建设目标下的张家界旅游环境管理对策研究

建设世界旅游精品是张家界制定的旅游业发展的战略目标，一流的旅游环境条件是实现这一目标的必备条件。然而，张家界目前的旅游环境与世界旅游精品存在差距，环境管理中存在基础性工作、基础性研究比较薄弱、制度不够健全等方面的问题，影响了环境管理效率。在分析研究张家界环境管理中存在问题的基础上，针对性地提出保护、改善环境的对策，是实现世界旅游精品战略目标的基础工作。     

青藏高原湖泊细菌种群结构的研究综述

青藏高原东北地区位于我国东部季风区、西北干旱区和青藏高原高寒区的交汇地带，人为影响较少，是研究人为影响与生物种群组成的理想场所。随着分子生物学技术的迅速发展，高原湖泊菌种群结构多样性研究越来越受到人们的重视并取得了重要成果。本文从青藏高原上应用的技术方法、细菌种群结构研究成果以及区域性的重要影响因素3个方面概述了湖泊细菌种群结构多样性研究在青藏高原上取得的进展。简单地讨论了种群多样性和影响因素的关系，对比发现，微生物种群结构的主要限制性因素会随着环境的变化发生改变。同时，微生物种群结构随着环境的变化实际上是其生理结构适应的结果。     

Aortic isthmus Doppler velocimetry: role in assessment of preterm fetal growth restriction

Intrauterine fetal growth restriction (IUGR) is an important pregnancy complication associated with significant adverse clinical outcome, stillbirth, perinatal morbidity and cerebral palsy. To date, no uniformly accepted management protocol of Doppler surveillance that reduces mortality and cognitive morbidity has emerged. Aortic isthmus (AoI) evaluation has been proposed as a potential monitoring tool for IUGR fetuses. In this review, the current knowledge of the relationship between AoI Doppler velocimetry and preterm fetal growth restriction is reviewed. Relevant technical aspects and reproducibility data are reviewed as we discuss AoI Doppler and its place within the existing repertoire of Doppler assessments in placental insufficiency. The AoI is a link between the right and left ventricles which perfuse the lower and upper body, respectively. The clinical use of AoI waveforms for monitoring fetal deterioration in IUGR has been limited, but preliminary work suggests that abnormal AoI impedance indices are an intermediate step between placental insufficiency-hypoxemia and cardiac decompensation. Further prospective studies correlating AoI indices with arterial and venous Doppler indices and perinatal outcome are required before encorporating this index into clinical practice. Copyright © 2010 John Wiley & Sons, Ltd.     

圆柱体相似试件的拉裂破坏模型研究

首先简单介绍了单轴压缩试验的具体情况。对于拉裂破坏模式,提出了相应的力学计算模型,并建立了抗压强度和抗拉强度的关系式。对于由拉裂面的存在而导致试件最终破坏的计算模型,提出了4种相应的假设。其中,对4种特征的拉裂面建立了抗压强度和抗拉强度的关系式。