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381.
Biodiversity provides many ecosystem functions and services in the coal mine areas and plays an important role in improving the environment and sustainable development of mining area. From the view of coal mining-damage-the whole process of reclamation, the biodiversity conservation planning and biodiversity survey, monitoring and evaluation technology were briefly introduced before coal exploiting. The main contents for biodiversity conservation and technology including the protection of topsoil seed bank, soil fauna, biological soil crusts and optimization techniques of concurrent mining and reclamation during coal mining and the operational phase were elaborated. The key factors affecting biodiversity restoration in land reclamation stage were analyzed. The research on soil improvement and revegetation was discussed. Finally, the development direction of research about conservation and restoration of biodiversity in land reclamation of coal mine were proposed. It may provide some ideas for further promoting the research in this area.  相似文献   
382.
半潜平台疲劳热点应力长期分布参数研究   总被引:1,自引:1,他引:0  
明确热点应力长期Weibull分布的参数是船舶与海洋工程结构应用疲劳简化分析方法的关键之一。以某深水半潜式平台为研究对象,通过整体结构有限元计算得到热点应力传递函数,结合波浪散布图计算热点应力长期分布概率函数,采用最小二乘法对热点应力长期Weibull分布进行参数估计。研究结果可为疲劳简化分析方法在半潜平台上的应用提供参考。  相似文献   
383.
中国海洋底栖生物学发展回顾与展望*   总被引:2,自引:0,他引:2  
海洋底栖生物是海洋生态系统中的重要组成部分,在底层生态系统的能量流动和物质循环过程发挥着重要作用。我国的海洋底栖生物学经过数十年的发展,取得的许多研究进展和成果,但学科目前发展仍存在很多不足。总体而言,研究力量相对薄弱和分散,仍为相对弱势的一个学科,需成立专门的底栖生物学组织机构(分会),构建一个学科交流与合作的平台,整合业内的研究力量和资源,促进我国底栖生物学的研究与发展。本文分析了学科的现状和发展趋势,阐述了海洋底栖生物学分会在学科发展中的作用,并就未来发展提出了建议。  相似文献   
384.
The outbreak of COVID-19 raised numerous questions on the interactions between the occurrence of new infections, the environment, climate and health. The European Union requested the H2020 HERA project which aims at setting priorities in research on environment, climate and health, to identify relevant research needs regarding Covid-19. The emergence and spread of SARS-CoV-2 appears to be related to urbanization, habitat destruction, live animal trade, intensive livestock farming and global travel. The contribution of climate and air pollution requires additional studies. Importantly, the severity of COVID-19 depends on the interactions between the viral infection, ageing and chronic diseases such as metabolic, respiratory and cardiovascular diseases and obesity which are themselves influenced by environmental stressors. The mechanisms of these interactions deserve additional scrutiny. Both the pandemic and the social response to the disease have elicited an array of behavioural and societal changes that may remain long after the pandemic and that may have long term health effects including on mental health. Recovery plans are currently being discussed or implemented and the environmental and health impacts of those plans are not clearly foreseen. Clearly, COVID-19 will have a long-lasting impact on the environmental health field and will open new research perspectives and policy needs.  相似文献   
385.
《Comptes Rendus Geoscience》2014,346(1-2):45-51
In southern Corsica, three successive Upper Burdigalian coral reef episodes (R1, R2 subdivided into R2A and R2B subunits, and R3) developed within the Cala di Labra Formation. Tabular corals dominated under high water energy and siliciclastic input conditions. The R1 reefs show the highest coral diversity with 16 species described for the first time. A coral impoverishment was recorded in the R2 and R3 reefal episodes. The reefs did not reach a climax growth stage, except the R1 ones. Analogous to North Sardinian reefs, they reflect local vanishing conditions in the Corsican–Sardinian block through Upper Burdigalian because of constant siliciclastic inputs and deepening of the Bonifacio straight.  相似文献   
386.
Mangroves are highly productive environments that play important ecological and socioeconomic roles; however, they have been impacted to different degrees in most countries worldwide. The knowledge of which organisms inhabit this environment and their ecological interactions is the first step towards its conservation. The natural variability of environmental factors in mangroves provides numerous niches available to different species. Meiofauna have patchy patterns of distribution that are related to the availability of resources. Hence, meiofauna are expected to present a high diversity of different taxa occupying the different microhabitats offered by mangroves. This work aims to test the hypothesis that the assemblage structure of Nematoda varies significantly among mangrove microhabitats and to contribute knowledge on the meiofauna diversity in mangrove environments. This work was carried out in a mangrove region at Pernambuco state, Northeastern Brazil. Qualitative samples were collected in nine microhabitats which show different characteristics mainly in terms of presence of vegetation or another organism and sediment grain size. Univariate and multivariate analysis were applied to Nematoda genera abundance data. Our results demonstrate the existence of significant differences among microhabitats regarding nematode assemblage structure corroborating the hypothesis. Different Nematoda assemblages are present in at least seven microhabitats. These assemblages are composed of nematode genera with different trophic and morphological features, demonstrating a strong relationship between morphological diversity and ecological plasticity. Furthermore, this study also demonstrates the importance of the conservation of this ecosystem and its attributes.  相似文献   
387.
The outbreak of COVID-19 raised numerous questions on the interactions between the occurrence of new infections, the environment, climate and health. The European Union requested the H2020 HERA project which aims at setting priorities in research on environment, climate and health, to identify relevant research needs regarding Covid-19. The emergence and spread of SARS-CoV-2 appears to be related to urbanization, habitat destruction, live animal trade, intensive livestock farming and global travel. The contribution of climate and air pollution requires additional studies. Importantly, the severity of COVID-19 depends on the interactions between the viral infection, ageing and chronic diseases such as metabolic, respiratory and cardiovascular diseases and obesity which are themselves influenced by environmental stressors. The mechanisms of these interactions deserve additional scrutiny. Both the pandemic and the social response to the disease have elicited an array of behavioural and societal changes that may remain long after the pandemic and that may have long term health effects including on mental health. Recovery plans are currently being discussed or implemented and the environmental and health impacts of those plans are not clearly foreseen. Clearly, COVID-19 will have a long-lasting impact on the environmental health field and will open new research perspectives and policy needs.  相似文献   
388.
大火成岩省及地幔动力学   总被引:4,自引:1,他引:4       下载免费PDF全文
大火成岩省由一个体积巨大的、连续的、以富镁铁岩石占优势的喷出岩及其伴生的侵入岩组成,是一个全球现象。它包括大陆溢流玄武岩和伴生的侵入岩,火山被动边缘玄武岩,大洋高原、海岭、海山群和洋盆溢流玄武岩。Ontong Java和Kerguelen-Broken Ridge大洋高原、北大西洋火山被动边缘、德干和哥伦比亚河大陆溢流玄武岩是3个主要大火成岩省的典型代表。各种不同的大火成岩省在时空分布及组成上都具有相似性,它们具有非常大的体积、高的喷发速率,岩石类型以拉斑玄武岩为主。大火成岩省代表了地球上已知的最大的火山岩浆活动,记录了物质和能量从地球内部向外的大量转换。大火成岩省难以用板块构造来解释,可用热柱模式来解释,通常被认为是与来自下地幔的热柱“头”有关。大火成岩省是地球动力学过程在地壳的表现,因此大火成岩省参数可作为边界条件去反演地幔动力学过程。  相似文献   
389.
南海是西太平洋边缘海,有陆架、陆坡、岛礁、深海平原、海山、冷泉等多种生境,近10年来南海逐渐成为世界深海研究的热点。南海是中国海洋生物多样性最高的区域,与作为海洋生物多样性中心的印太珊瑚大三角区具有一定的环境与生物连通性,对南海的深海生物探测研究可丰富对西太平洋及印太交汇区生物多样性及地理分布格局的认知。目前有关南海的生物多样性研究主要集中在北部陆架浅海及岛礁,对于深海生物多样性认知明显不足。本研究梳理了全球深海生物多样性的主要国际战略布局,并对南海深海生物多样性SCIE论文发表情况进行了综合分析,探讨了南海深海生物多样性研究态势,对未来南海深海生物多样性调查与研究提出了研究展望和建议。  相似文献   
390.
研究全球经济海藻领域专利研发态势,为中国经济海藻技术研发提供参考。基于德温特专利数据库,采用Derwent data analyzer、Derwent innovation等分析工具和平台对1960—2020年经济海藻领域的专利文献进行分析。系统揭示半个多世纪以来经济海藻的全球专利数量变化趋势、专利技术构成、代表国家或地区、主要专利权人、热点技术分布与变迁等内容,同时以产业链为分析视角,梳理热点技术的上、中、下游区位,并通过国际间对比分析得到中国在经济海藻领域技术研发面临的机遇与挑战。中国在经济海藻领域的产业链上游(如海藻栽培)、产业链中游(如药物制剂的治疗活性和提取技术)和产业链下游(如食品烹饪、添加与保存、饲料、肥料和医疗制剂等领域)占据优势,与韩国和日本的产业竞争主要存在于产业链下游,如化妆品、个人护理品和生物杀菌剂等领域,当前缺乏对生物燃料、节能环保和环境修复的研发与关注。  相似文献   
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