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541.
Use of Descriptors of Ecosystem Functioning for Monitoring a National Park Network: A Remote Sensing Approach 总被引:1,自引:0,他引:1
Baseline assessments and monitoring of protected areas are essential for making management decisions, evaluating the effectiveness
of management practices, and tracking the effects of global changes. For these purposes, the analysis of functional attributes
of ecosystems (i.e., different aspects of the exchange of matter and energy) has advantages over the traditional use of structural
attributes, like a quicker response to disturbances and the fact that they are easily monitored through remote sensing. In
this study, we described the spatiotemporal patterns of different aspects of the ecosystem functioning of the Spanish national
parks and their response to environmental changes between 1982 and 2006. To do so, we used the NOAA/AVHRR-GIMMS dataset of
the Normalized Difference Vegetation Index (NDVI), a linear estimator of the fraction of photosynthetic active radiation intercepted
by vegetation, which is the main control of carbon gains. Nearly all parks have significantly changed during the last 25 years:
The radiation interception has increased, the contrast between the growing and nongrowing seasons has diminished, and the
dates of maximum and minimum interception have advanced. Some parks concentrated more changes than others and the degree of
change varied depending on their different environmental conditions, management, and conservation histories. Our approach
identified reference conditions and temporal changes for different aspects of ecosystem functioning, which can be used for
management purposes of protected areas in response to global changes. 相似文献
542.
Agri-environment programs aim to secure environmental and social stewardship services through payments to farmers. A critical
component of many agri-environment programs is an agri-environment index (AEI) used to quantify benefits and target investments.
An AEI will typically comprise multiple indicators, which are weighted and combined using a utility function, to measure the
benefit of investment options (e.g., projects, farms, regions). This article presents a review of AEIs with 11 case studies
from agri-environment programs in the United States, Australia, and the United Kingdom. We identify a generic procedure used
to define AEIs and explore the implications of alternative methodological approaches. We conclude that AEIs have become an
extremely important policy instrument and make suggestions for their improvement. 相似文献
543.
随着社会经济的发展,突发性环境污染事故频繁发生。为有效预防和控制突发性环境污染事故,各国开发了相应的应急管理系统,为污染事故处置提供应对技术和决策支持。本文综合论述了国内外突发环境污染事故应急管理系统的开发和应用情况、服务内容及特点,并对我国应急管理的发展提出建议。 相似文献
544.
本文介绍了可靠性标准体系与参数体系,可靠性的分析与设计方法,可靠性试验的发展趋势,指出可靠性管理是产品可靠性工作的核心,以及提高电子设备可靠性的发展策略。 相似文献
545.
546.
547.
Disaster management (DM) is a continuous, highly collaborative process involving governments, DM organisations, responders, the construction sector, and the general public. Most research approaches to DM include the development of information and communication technologies (ICT) to support the collaboration process rather than the creation of a collaboration process to provide information flows and patterns. An Intelligent Disaster Collaboration System (IDCS) is introduced in this paper as a conceptual model to integrate ICT into DM and the mitigation process and to enhance collaboration. The framework is applicable to the collaboration process at the local, regional and national levels. Within this context, the deployment of ICT tools in DM is explored and scenario-based case studies on flooding and terrorism—examples of natural and human-induced disasters, respectively—are presented. Conclusions are drawn regarding the differences found in collaboration patterns and ICT used during natural and human-induced disasters and the differences between currently available ICT and proposed ICT. 相似文献
548.
企业绿色管理已有研究将制度和技术在两个不同的领域进行分析,忽视了绿色管理是对制度和技术压力的反应,两种压力同时并存甚至相互影响.技术创新的"正外部性"和环境问题的"负外部性"要求在分析企业绿色管理行为时,整合制度和环境技术创新以及二者的相互关系.已有文献普遍强调作为强制性制度的环境规制对技术创新的驱动效果,而较少关注制度压力与技术创新的交互作用.通过对企业面临的制度压力和技术压力相互关系的分析,本文构建了基于制度与技术情境的企业绿色管理战略选择模型.企业绿色管理战略是制度压力和环境技术等因素相互作用的结果,对制度压力的反应有助于技术效率的提高,而企业所处的制度情境也影响到其对技术压力的响应方式.针对我国目前的环境监管现状,本文为制定有助于清洁技术采纳和扩散的环境政策提出相应建议. 相似文献
549.
国外流域管理的成功经验对雅砻江流域管理的启示 总被引:2,自引:0,他引:2
世界各国对流域管理的不断探索,大大丰富了流域管理的理论和实践,流域管理已成为国家和地区水资源管理的一种行之有效的模式。我国的流域管理尚处于最初的探索阶段,如何借鉴国外流域管理的成功经验,形成有效的流域管理模式已成为我国水资源管理的主要任务之一。为了给国内流域管理实践提供一些有益的借鉴,分析总结了具有代表性的美国田纳西河流域管理模式、澳大利亚墨累 达令河流域管理模式和英国泰晤士河流域管理模式的成功经验和存在的问题。以雅砻江流域水电开发为实例,在对该流域的实际情况进行全面分析的基础上,将该流域与上述三条流域进行比较,充分借鉴三条流域管理模式成功经验,提出了雅砻江流域管理的相关对策和建议。 相似文献
550.
Both the Aalborg Commitments and the guidance on integrated urban environmental management and sustainable urban transport
plans proposed by the EU Thematic Strategy on the Urban Environment foresee a baseline review as the first step in developing
integrated urban management plans and systems. A baseline review of urban sustainability undertaken in Riga reveals significant
discrepencies between the sustainability criteria of the Aalborg Commitments and the: responsibilities and competencies of
the municipal government and administration as defined by statutes; policy goals and measures defined in municipal planning
documents; policy goals and measures defined in the Riga Development Plan. To better orient the mandate of the municipality
towards sustainable development, municipal statutes should be supplemented to more fully reflect the issues defined by the
Aalborg Commitments and should include sustainability as a goal. In order to strengthen the implementation of sustainable
development specific policy goals, measures and targets should be formulated for all the Aalborg Commitments issues when revising
existing municipal planning documents or developing a municipal sustainable development management plan. An analysis of the
European Common Indicators and the State of the Environment in Riga 2001 indicators indicates that they can only partially
fulfill a monitoring function for the implementation of the Aalborg Commitments. This highlights a need to better coordinate
sustainable development initiatives at the European level. The methodology used for the baseline review in Riga is useful
for assessing the status of urban sustainability when preparing integrated urban management plans or systems, but requires
testing elsewhere.
Readers should send their comments on this paper to BhaskarNath@aol.com within 3 months of publication of this issue. 相似文献