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Much biodiversity data is collected worldwide, but it remains challenging to assemble the scattered knowledge for assessing biodiversity status and trends. The concept of Essential Biodiversity Variables (EBVs) was introduced to structure biodiversity monitoring globally, and to harmonize and standardize biodiversity data from disparate sources to capture a minimum set of critical variables required to study, report and manage biodiversity change. Here, we assess the challenges of a ‘Big Data’ approach to building global EBV data products across taxa and spatiotemporal scales, focusing on species distribution and abundance. The majority of currently available data on species distributions derives from incidentally reported observations or from surveys where presence‐only or presence–absence data are sampled repeatedly with standardized protocols. Most abundance data come from opportunistic population counts or from population time series using standardized protocols (e.g. repeated surveys of the same population from single or multiple sites). Enormous complexity exists in integrating these heterogeneous, multi‐source data sets across space, time, taxa and different sampling methods. Integration of such data into global EBV data products requires correcting biases introduced by imperfect detection and varying sampling effort, dealing with different spatial resolution and extents, harmonizing measurement units from different data sources or sampling methods, applying statistical tools and models for spatial inter‐ or extrapolation, and quantifying sources of uncertainty and errors in data and models. To support the development of EBVs by the Group on Earth Observations Biodiversity Observation Network (GEO BON), we identify 11 key workflow steps that will operationalize the process of building EBV data products within and across research infrastructures worldwide. These workflow steps take multiple sequential activities into account, including identification and aggregation of various raw data sources, data quality control, taxonomic name matching and statistical modelling of integrated data. We illustrate these steps with concrete examples from existing citizen science and professional monitoring projects, including eBird, the Tropical Ecology Assessment and Monitoring network, the Living Planet Index and the Baltic Sea zooplankton monitoring. The identified workflow steps are applicable to both terrestrial and aquatic systems and a broad range of spatial, temporal and taxonomic scales. They depend on clear, findable and accessible metadata, and we provide an overview of current data and metadata standards. Several challenges remain to be solved for building global EBV data products: (i) developing tools and models for combining heterogeneous, multi‐source data sets and filling data gaps in geographic, temporal and taxonomic coverage, (ii) integrating emerging methods and technologies for data collection such as citizen science, sensor networks, DNA‐based techniques and satellite remote sensing, (iii) solving major technical issues related to data product structure, data storage, execution of workflows and the production process/cycle as well as approaching technical interoperability among research infrastructures, (iv) allowing semantic interoperability by developing and adopting standards and tools for capturing consistent data and metadata, and (v) ensuring legal interoperability by endorsing open data or data that are free from restrictions on use, modification and sharing. Addressing these challenges is critical for biodiversity research and for assessing progress towards conservation policy targets and sustainable development goals.  相似文献   
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Duin D  van Besselaar P 《ZooKeys》2011,(150):193-210
The research environment of scholars is increasingly web-based. This makes it urgent to study the effects of moving to the Web on research practices, scholarly output and innovation. We propose a theoretical framework and a methodology to study these effects. In a pilot study, we apply theory and method on an online community in biodiversity research, to demonstrate the feasibility of the approach. We also indicate the practical relevance of this kind of analysis for improving the quality of virtual research environments. In the last section, directions for further research are suggested.  相似文献   
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In sustainable agricultural development, integrated pest management (IPM) can play a key role in the reduction of crop losses, thereby increasing productivity while minimizing environmental contamination and health hazards. In recent years, agricultural research and development partners have pioneered outstanding contributions in IPM, notably in varietal resistance against pests, biological control of alien invasive species, substitution of inorganic pesticides with biopesticides, new export market opportunities, and new tools in biotechnology. Success stories are not limited to these areas, but are also found in the areas of human capital development, information management, and participatory approaches. The potential of IPM to contribute to poverty alleviation and food security is, however, poorly realized in Africa due to a myriad of factors, including inadequate deployment of high-yielding crop varieties, harmful pesticide regimes, political instability, conflicts in social values and civil wars, inappropriate agricultural policies, biased global trade policies, lack of market information, and poor rural infrastructures. Few African countries have adopted IPM as the official national crop protection policy and there is no framework for resource allocation to support widespread promotion of research and training in IPM. This calls for reshaping and revisiting a number of policies related to food production and agricultural development, in order to encourage partnership and participation in the identification, analysis, advocacy, and follow-up of agricultural policy issues as well as public awareness of the effect of pests and diseases on food security and the environment.  相似文献   
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ABSTRACT

“Critical infrastructures” are exceedingly complex and highly interconnected. In order to gain a full understanding and comprehensive awareness of the risks associated with critical infrastructures it becomes essential to consider in a coherent way all the aspects that may cause a failure of such systems. That is, there is a need for a systemic approach to interdependencies among critical infrastructures. The article presents the application of a systemic safety management system (SSMS) model to interdependency modeling for the case of the Mexico City Metro transport network. The model has highlighted that interdependencies occur vertically and horizontally. Horizontal interdependency occurs at every level of recursion and can be: operational, managerial, and environmental. Vertical interdependency, on the other hand, occurs between two levels of recursion only. The SSMS model has shown the potential to be used to model interdependencies among critical infrastructures. It is hoped that the approach presented may help to gain a better understanding of critical infrastructure interdependency.  相似文献   
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城市遮阴环境变化对大叶黄杨光合过程的影响   总被引:1,自引:0,他引:1  
于盈盈  胡聃  郭二辉  肖强  柳敏  张小飞 《生态学报》2011,31(19):5646-5653
城市遮阴与自然生态系统遮阴环境不同,它由城市中的建筑、基础设施等人工构筑物所产生,并对植物光合过程产生影响。采用Li-6400便携式光合作用测定系统对北京市不同建筑遮阴环境下的生态因子特征及大叶黄杨光合参数特性进行了现场实验对比观测与分析。研究显示:(1)城市建筑或基础设施布局或格局变化导致建筑遮阴环境光、温等生态因子的差异性变化,主要体现在光合有效辐射(PAR)在时间分布及强度上的显著差异。(2)遮阴改变大叶黄杨的光合参数,日净光合速率曲线为不规则单峰型,由遮阴进入太阳直射时,净光合速率(Pn)明显升高,随遮阴程度加重峰值时间有后延现象,完全遮阴时净光合速率最低。(3)大叶黄杨叶片在有一定时间太阳直射的中度遮阴(2.3h和5.5h)下适应性良好,日均净光合速率、光补偿点(LCP)、光合能力(Pnmax)、叶面积(LA)、比叶重(LMA)没有显著差异,植物主要通过光合色素含量及组成的改变来适应太阳直射时间变短(2.3h)的遮阴环境。(4)遮阴改变植物的光暗适应策略,没有阳光直射的重度遮阴下,大叶黄杨通过其光合、形态、光合色素等多方面的改变来适应遮阴环境,建筑重度遮阴严重影响植物光合过程。探讨了不同程度建筑遮阴对植物光合作用的影响及植物的适应机制,为基于提高其生态服务功能的树种配置和城市规划提供科学依据。  相似文献   
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This work provides an overview of plant diversity in the municipality of Rome (Italy) through an assessment of the flora in urban and suburban sectors of the city. It is aimed at providing the knowledge required to support proactive action for plant conservation. On the basis of a literature-derived catalogue and of an extensive survey campaign, the flora was investigated in terms of conservation interest; habitat types and locations that require protection measures were identified according to the occurrence of valuable native plants. Valuable species exclusive of the urban sector are threatened by the compaction trend affecting the urban fabric. Such species occur mainly in ruderal environments and fallows of archaeological sites and urban parks, near river courses and in remnants of natural forests. Valuable species exclusive of the suburban sector are threatened by urban sprawl. They occur prevalently in wet environments of the subcoastal strip and in coastal sands, Mediterranean maquis, tuffaceous gorges, sulphur springs and archaeological sites. The results highlight the need to preserve the complexity of the land mosaic, especially within the urban matrix, and to strengthen the existing environmental protection tools in the suburban area against foreseeable land cover changes.  相似文献   
8.
New forms of life, ethical plateaus, and civic political contests arise through the creation of new technoscientific infrastructures in which market, law, code, and norms compete for hegemonic control over the rules of play. A review of a panel of four articles interrogates agendas for ethnographies of the locally diverse peopling of such new infrastructures, including the continuing renegotiation of historical and emergent modalities of ethical and political reason.  相似文献   
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本文基于真实的案例研究:文章呈现了肖普朗镇(Sopron)近8年城市公共空间的更新过程,这座历史悠久的小镇是宜昌(中国)的姐妹城市,它坐落于中欧与东欧交界处,匈牙利(Hungary)西部。作为一项长期研究、规划和协商过程的组成部分,该公共空间更新项目的第一期也是最重要的工程阶段(包括洋葱形城市中心区在内),在后续工程规划过程中,就已经完成并获得了多项匈牙利国内及国际奖项。由此,该项目所承担的风险就是双倍的。一方面,考虑到城市的公共设施是一种很特殊的硬件,我们已经通过减少场地中主要的机动车交通和停车空间对其进行了更新。相反,我们为行人开放了城市广场,而且加强了广场与周围建筑底层商铺之间的联系。另一方面,任何活动都可以在此发生,因为从那时起,焕然一新的户外就餐区,就为众多的城市事件、庆典提供了活动场所,同时也为一般的城市步行功能提供了空间。随着更新过程中复杂技术和施工工艺的出现,我们力图展现潜藏在历史以及城市记忆中的场地空间特征:城堡街(Várkerület)的前身是环绕着历史城区的被水覆盖的护城河区域。这决定了它在空间中特殊的形态、模式以及宽度变化。这种空间格局的重构为适应21世纪功能需求的城市复兴奠定了坚实的基础。所有这些都是在一项特殊的研究过程中进行的,这些设计结果可以直接应用在设计原则之中。该过程具有先进性,同时伴随着一个特殊的研究过程:在方法论层面得出可供直接使用的设计原则。  相似文献   
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