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1.
Gene E. Likens 《Ambio》2021,50(2):278
Early studies published in Ambio showed large-scale acidification of lakes in southern Sweden and Norway from acid rain. These studies were important for delimiting various scientific issues and thus for eventually contributing to legislation, which reduced emissions of sulfur dioxide and nitrogen oxides and helped to mitigate this major environmental problem. Long-term studies and monitoring in Sweden and Norway and at Hubbard Brook Experimental Forest in New Hampshire helped guide this legislation in Europe and in the USA.  相似文献   
2.
梳理了高校实验室环境-安全-健康准入制度包含的管理内容,从人员管理、设备管理、试剂管理、实验环境管理角度进行了分析。根据现有实验室安全信息化系统运行情况,探讨了将实验室安全信息化系统与实验室信息化系统、设备管理信息化系统进行数据融合和功能优化的要点,重点分析了设备采购及管理系统、实验室安全教育与考试系统、实验室安全检查系统、试剂管理平台、实验室门禁管理系统在功能上的内在关联,从而通过试剂管理平台、实验室门禁控制系统、设备采购系统实现实验室环境-安全-健康准入制度的强制执行。研究发现,高校与环境监测实验室、院系实验室安全管理部门联合促进实验室安全信息化系统、实验室信息化系统、设备管理信息化系统的数据共享与功能升级,可以丰富实验室安全准入制度的内涵和管理手段,加强实验室安全准入制度的强制执行力,提高实验室安全管理效率。  相似文献   
3.
为充分发挥立法的引领和推动作用,不断完善中国矿山安全法律法规体系,分析我国矿山安全领域的立法现状,借鉴美国矿山安全立法经验及启示,立足于我国矿山安全监管监察体制革新的新形势和新要求,提出了以《矿山安全法》为基本法,以行政法规、部门规章、监察手册和强制性标准为支撑的新发展阶段矿山安全法规标准体系,为中国矿山安全领域立法提供参考。  相似文献   
4.
地表水环境遥感监测关键技术与系统   总被引:1,自引:0,他引:1  
介绍了地表水环境遥感监测的关键技术与系统及其典型应用,其代表性机理模型和应用示范成果主要来自于中国科学院遥感与数字地球研究所的高光谱遥感团队在最近几年中取得的一些研究进展,主要包括建立了基于改进双峰法的水体分布自动化遥感提取方法,实现了简单、高效和高精度的水体提取;提出了大型湖泊长时序水量估算方法,并以青藏高原湖区为例,重建了典型湖泊面积、水位和水量序列;发展了基于“软分类”的典型内陆水体叶绿素a浓度反演方法,构建了基于生物光学模型的高度浑浊水体悬浮物浓度遥感反演半解析方法,提高了反演方法的区域和季节适用性;构建了基于水色指数的大范围湖库营养状态和透明度遥感监测方法,实现了全球大型湖库营养状态遥感监测,以及全国大型湖库透明度遥感监测;在此基础上,开发了地表水环境遥感监测系统,提高了水环境遥感监测效率,促进了卫星遥感在水环境监测中的高精度业务化应用。  相似文献   
5.
Estimates of biodiversity change are essential for the management and conservation of ecosystems. Accurate estimates rely on selecting representative sites, but monitoring often focuses on sites of special interest. How such site-selection biases influence estimates of biodiversity change is largely unknown. Site-selection bias potentially occurs across four major sources of biodiversity data, decreasing in likelihood from citizen science, museums, national park monitoring, and academic research. We defined site-selection bias as a preference for sites that are either densely populated (i.e., abundance bias) or species rich (i.e., richness bias). We simulated biodiversity change in a virtual landscape and tracked the observed biodiversity at a sampled site. The site was selected either randomly or with a site-selection bias. We used a simple spatially resolved, individual-based model to predict the movement or dispersal of individuals in and out of the chosen sampling site. Site-selection bias exaggerated estimates of biodiversity loss in sites selected with a bias by on average 300–400% compared with randomly selected sites. Based on our simulations, site-selection bias resulted in positive trends being estimated as negative trends: richness increase was estimated as 0.1 in randomly selected sites, whereas sites selected with a bias showed a richness change of −0.1 to −0.2 on average. Thus, site-selection bias may falsely indicate decreases in biodiversity. We varied sampling design and characteristics of the species and found that site-selection biases were strongest in short time series, for small grains, organisms with low dispersal ability, large regional species pools, and strong spatial aggregation. Based on these findings, to minimize site-selection bias, we recommend use of systematic site-selection schemes; maximizing sampling area; calculating biodiversity measures cumulatively across plots; and use of biodiversity measures that are less sensitive to rare species, such as the effective number of species. Awareness of the potential impact of site-selection bias is needed for biodiversity monitoring, the design of new studies on biodiversity change, and the interpretation of existing data.  相似文献   
6.
To study the effects of the tectonic stress environment on the tectonophysical features of deformed coal, No.8 Mine in the Pingdingshan mine area is used as a study area and the relationship between the development of deformed coal, distribution of fractures, formation of deformed coal and tectonic stress environment are analyzed. The results indicate that the thickness of the bedrock layer should be included in the analysis of the tectonic stress environment for a region of intense tectonic activity. Although the reverse faulting stress regime can control the development of deformed coal, the C seam is extremely sensitive to the stress regime. The most advantageous direction of the deformed coal fractures is consistent with the regional maximum principal stress, and the development of fractures is closely related to the evolution of the tectonic stress environment. The fracture density of the E seam presents a uniform distribution, yet that of the C seam is completely heterogeneous. Superposition and compounding of the tectonic communities evidently increase the fracture density of the deformed coal. There is a relatively apparent boundary between the different types of deformation, which gradually transform from brittle to ductile with a decreasing lateral pressure coefficient. A generalized deformation pattern of the deformed coal is proposed and can be divided into frictional sliding and solid flow.  相似文献   
7.
Reductions in global bee populations are threatening the pollination benefits to both the planet and people. Whilst the contribution of bee pollination in promoting sustainable development goals through food security and biodiversity is widely acknowledged, a range of other benefits provided by bees has yet to be fully recognised. We explore the contributions of bees towards achieving the United Nation’s Sustainable Development Goals (SDGs). Our insights suggest that bees potentially contribute towards 15 of the 17 SDGs and a minimum of 30 SDG targets. We identify common themes in which bees play an essential role, and suggest that improved understanding of bee contributions to sustainable development is crucial for ensuring viable bee systems.  相似文献   
8.
A growing body of literature examines how human bonds with place influence engagement with climate change and other environmental issues. Yet, studies in this vein derive from a number of disconnected literatures with a variety of place concepts employed. We set out to assess the current state of knowledge in this field and provide a framework for analysing dimensions of relations to place and their links with environmental engagement. We systematically analysed the characteristics of 66 studies identified for: focus of research, location, methods, and findings, particularly whether relationships to place aided in environmental engagement. We also categorised the studies according to our dimensions of place relations framework, cultural and environmental contexts, and intensity of climate impacts experienced. The answer to our guiding research question – whether place attachment was an effective way to communicate with people about climate change and get them actively engaged with it – was yes (74.2%), but with considerable variation according to these characteristics and dimensions. Based on this analysis, we identify gaps in current research and suggest critical paths for future research, especially in terms of geography and demography because of their implications for justice and equity in the processes of climate change mitigation and adaptation. Needed future research includes studies of place relations in regards to climate change specifically, studies in the Global South, of minority populations, beyond rural areas, and qualitative or mixed-method studies able to draw out the complexities of relations to place.  相似文献   
9.
利用2013年11月武汉市逐日空气质量资料、地面气象观测资料、NCEP/NCAR再分析资料和L波段雷达探空资料,通过WRF模式模拟空气污染生消过程中的局地气象条件变化,探讨特殊地形条件下边界层结构变化和局地环流在污染物生消过程中的作用和影响。结果表明:(1)武汉地区当背景环流场强的时候,由地形引起的局地流场对污染物扩散的影响就弱,反之当背景环流场弱的时候, 地形对流场影响明显:夜间为山风,白天为谷风。夜间山风与偏西北气流及偏东气流在武汉及周边地区辐合,形成气流汇聚带,在武汉地区形成一个反复污染带,即由地形引起的局地流场对污染物扩散的贡献就大;(2)武汉地区发生空气污染时,地面湿度较高,边界层呈上干下湿状态,其特征为暖而干且有偏东小风,这导致污染物不断堆积和重污染过程的形成。  相似文献   
10.
This paper tackles the process of energy transition from a transactional perspective. It addresses the governance of energy transition by studying its local actualizations, moving beyond purely technical and normative readings. The paper shows that through the local socio-technological energy systems, sustainability governance filters down to the level of individual, everyday behavior, thus questioning the link between public and private spaces, especially regarding the issue of housing. Going beyond the results commonly yielded by transition studies, which favor large-scale analysis, it details how the discourse of citizen involvement, which often boils down to a mere call to control one’s individual energy consumption, conceals environmental inequalities, confirming the socioeconomic divide materialized in deprived areas such as public housing estates or remote rural areas. From a methodological standpoint, the analysis is based on four case studies in Northeast France, in more or less privileged areas, and in both urban and rural environments: the renovation of a heating network in the public housing estate of Cité de l’Ill, north of Strasbourg; the solar energy systems designed for property owners in Plobsheim, a residential suburb of Strasbourg; the energy-efficient equipment set up in a public housing estate in the city of Saint-Dié, in the Vosges; and citizen participation in a cooperative program to finance wind turbines in the small Alsacian city of Saâles, in a mountain rural area. The paper draws on the results of these sociological investigations, carried out using field observations, questionnaires and interviews.  相似文献   
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