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381.
基于金乡县南部地区土地质量地球化学调查与评价项目,系统采集表层土壤和大蒜样品,对As、Cd、Cr、Cu、Hg、Ni、Pb、Zn共8种重金属元素全量及形态数据进行深入分析,研究发现,土壤重金属形态除Cd、Hg外以残渣态占绝对优势;重金属生物可利用系数与SOM、pH、CEC均呈负相关;大蒜植株不同部位对元素的富集特征具有明显差异性,As、Cd、Cr、Pb、Ni、Cu、Zn表现为须根>叶身>假茎>蒜头;蒜头Cd与土壤Cd全量呈显著性正相关,其余元素与对应土壤中全量相关关系不明显。 相似文献
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随着“数字城市”建设的推进,地理信息系统建设进入全面发展阶段,加快基础空间数据更新频率的需求日趋强烈。如何有效的使用基础空间数据,为城市建设增砖加瓦成为政府部门关注的问题。该文主要阐述某个城市的系统方案设计、体系架构、网络架构与实现功能,为其他三维数字城市管理平台的建设提供一定的参考依据。 相似文献
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Scientists’ ideas, beliefs, and discourses form the frames that shape their choices about which research to pursue, their approaches to collaboration and communicating results, and how they evaluate research outputs and outcomes. To achieve ocean sustainability, there are increasing calls for new levels of engagement and collaboration between scientists and policy-makers; scientists’ willingness to engage depends on their current and evolving frames. Here, I present results about how scientists involved in diverse fields of ocean research perceived their role as scientists working at or near the ocean science–policy interface and how this related to their perceptions regarding ocean research priorities. The survey of 2187 physical, ecological and social scientists from 94 countries showed that scientists held different perspectives about their appropriate level of engagement at the ocean science–policy interface and the relative primacy of science versus politics in formulating ocean policy. Six clusters of scientists varied in their frames; three clusters accounted for 94% of the sample. Of 67 research questions identified from 22 research prioritization and horizon scanning exercises, the top eight were shared among all three clusters, showing consistency in research priorities across scientists with different framings of their role at the science–policy interface. Five focused on the mechanisms and effects of global change on oceans, two focused on data collection and management for long-term ocean monitoring, and one focused on the links between biodiversity and ecological function at different scales. The results from this survey demonstrated that scientists’ framings of the role of ocean science at the science–policy interface can be quantified in surveys, that framing varies among scientists, and that research priorities vary according to the framings. 相似文献
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Adaptive governance focuses our attention on the relationships between science and management, whereby the so-called ‘gaps’ between these groups are seen to hinder effective adaptive responses to biophysical change. Yet the relationships between science and governance, knowledge and action, remain under theorized in discussions of adaptive governance, which largely focuses on abstract design principles or preferred institutional arrangements. In contrast, the metaphor of co-production highlights the social and political processes through which science, policy, and practice co-evolve. Co-production is invoked as a normative goal (Mitchell et al., 2004) and analytical lens (Jasanoff, 2004a, Jasanoff, 2004b), both of which provide useful insight into the processes underpinning adaptive governance. This paper builds on and integrates these disparate views to reconceptualize adaptive governance as a process of co-production. I outline an alternative conceptual framing, ‘co-productive governance’, that articulates the context, knowledge, process, and vision of governance. I explore these ideas through two cases of connectivity conservation, which draws on conservation science to promote collaborative cross-scale governance. This analysis highlights the ways in which the different contexts of these cases produced very different framings and responses to the same propositions of science and governance. Drawing on theoretical and empirical material, co-productive governance moves beyond long standing debates that institutions can be rationally crafted or must emerge from context resituate adaptive governance in a more critical and contextualized space. This reframing focuses on the process of governance through an explicit consideration of how normative considerations shape the interactions between knowledge and power, science and governance. 相似文献