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Thomas Kenkmann Alex Deutsch Klaus Thoma Matthias Ebert Michael H. Poelchau Elmar Buhl Eva-Regine Carl Andreas N. Danilewsky Georg Dresen Anja Dufresne Nathanaël Durr Lars Ehm Christian Grosse Max Gulde Nicole Güldemeister Christopher Hamann Lutz Hecht Stefan Hiermaier Tobias Hoerth Astrid Kowitz Falko Langenhorst Bernd Lexow Hanns-Peter Liermann Robert Luther Ulrich Mansfeld Dorothee Moser Manuel Raith Wolf Uwe Reimold Martin Sauer Frank Schäfer Ralf Thomas Schmitt Frank Sommer Jakob Wilk Rebecca Winkler Kai Wünnemann 《Meteoritics & planetary science》2018,53(8):1543-1568
This paper reviews major findings of the Multidisciplinary Experimental and Modeling Impact Crater Research Network (MEMIN). MEMIN is a consortium, funded from 2009 till 2017 by the German Research Foundation, and is aimed at investigating impact cratering processes by experimental and modeling approaches. The vision of this network has been to comprehensively quantify impact processes by conducting a strictly controlled experimental campaign at the laboratory scale, together with a multidisciplinary analytical approach. Central to MEMIN has been the use of powerful two-stage light-gas accelerators capable of producing impact craters in the decimeter size range in solid rocks that allowed detailed spatial analyses of petrophysical, structural, and geochemical changes in target rocks and ejecta. In addition, explosive setups, membrane-driven diamond anvil cells, as well as laser irradiation and split Hopkinson pressure bar technologies have been used to study the response of minerals and rocks to shock and dynamic loading as well as high-temperature conditions. We used Seeberger sandstone, Taunus quartzite, Carrara marble, and Weibern tuff as major target rock types. In concert with the experiments we conducted mesoscale numerical simulations of shock wave propagation in heterogeneous rocks resolving the complex response of grains and pores to compressive, shear, and tensile loading and macroscale modeling of crater formation and fracturing. Major results comprise (1) projectile–target interaction, (2) various aspects of shock metamorphism with special focus on low shock pressures and effects of target porosity and water saturation, (3) crater morphologies and cratering efficiencies in various nonporous and porous lithologies, (4) in situ target damage, (5) ejecta dynamics, and (6) geophysical survey of experimental craters. 相似文献
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Managing the risks of extreme events such as natural disasters to advance climate change adaptation (CCA) has been a global focus. However, a critical challenge in supporting CCA is to improve its linkage with disaster risk reduction (DRR). Based on discussions on similarities and differences between CCA and DRR concerning their spatial–temporal scales, main focuses, preferred research approaches and methodologies, etc., this paper tentatively put forward an analytical framework of “6W” for linking DRR with CCA. This framework presented preliminary answers to a series of fundamental questions, such as “What is adaptation with respect to disaster risk?” “Why adaptation is needed?” “Who adapt to what?” “How to adapt?” “What are the possible principles to assess the adaptation effect?” To bridge the research gaps between CCA and DRR, it is imperative to associate the adaptation actions with both near-term disaster risk and long-term climate change and formulate adaptation strategies at various spatial–temporal scales by embracing uncertainty in a changing climate. 相似文献
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Seasonal water scarcity in southern China has been an issue of concern for many years. The increased frequency of low precipitation
in the growing season of rice created a flurry of discussions in the academic and policy arenas. These events severely disrupted
the supply of irrigation water for agriculture in paddy field areas and posed a substantial threat to farmers’ livelihoods.
Within a broader context of accessing farmers’ resilience to agricultural drought, this paper focuses on the response mechanisms
and adaptive strategies adopted by farming households in three types of areas (Plain, Hill, Mountain) in Dingcheng, Hunan
Province. With the increasing drought frequency and the pressure from the demand for livelihood improvement, farmers’ response
mechanisms have evolved, expanding from short-term adjustments to long-term adaptations, and switching focus from securing
reliable water sources to improving irrigation efficiency and diversifying both on- and off- farm productions. The three types
of geographic units have different resilience profiles and have developed diverse patterns of adaptive processes that update
the conceptual model of Disaster Resilience of “Loss-Response” of Location. It presents a temporal dimension to the study
of resilience, which is largely missing from the current literature and provides insights into how to enhance farmers’ response
capacities in the face of agricultural drought in southern China. 相似文献
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北京城乡过渡区土地利用变化驱动力分析 总被引：52，自引：1，他引：52
在多时相遥感数据和实际调查数据的支持下，采用典型样带和样点相结合的研究方法，对北京西部城乡过渡区的土地利用/覆盖变化驱动力进行了研究。结果表明，研究区的土地利用/覆盖变化受到了不同层次、多种驱动力的综合作用，人类活动从整体上改变着城乡过渡区的景观特征，政策体制转变下的经济高速增长和快速的城市化过程是北京城乡过渡区土地利用/覆盖变化的根本原因。在这个过程中，城市投资和产业的转变与农村农业用地内部的结构调整相互结合，从城市和农村两个方向共同推动着北京城乡过渡区的土地利用/覆盖变化，而地形、交通等因素则从局部尺度上决定着土地利用/覆盖变化的方向。此外，人类个体的行为选择，尤其是就业和消费选择，也在一定程度上对北京城乡过渡区的土地利用/覆盖变化起着调整和修改作用。 相似文献
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暴雨洪水灾害人口损失评估方法研究进展 总被引：1，自引：1，他引：0
在气候变化与城市化背景下,暴雨洪水灾害损失风险加剧,给人口生命安全带来极大威胁,评估暴雨洪水灾害的人口损失成为灾害风险研究关注的焦点问题。本文基于灾害系统理论,归纳了基于“致灾因子(H)—承灾体(V)—孕灾环境(E)—人口损失(D)”的暴雨洪水灾害人口损失评估的概念框架;基于现有国内外典型研究,梳理了相应的指标体系和研究方法,以“影响指标—损失指标—分析方法”多维图显示,认为“综合影响因素—人口损失”关系分析是评估暴雨洪水灾害人口损失的核心。目前人口损失的评估方法依据其考虑的要素可划分为：基于“H-D”关系的脆弱性曲线法、基于“H-V-E-D”关系的多要素综合法和刻画过程的灾害系统模拟法等。着重从数据可获取性和方法有效性两方面进行综述,认为单一方法不能满足人口损失风险评估的需求,因此从灾害系统角度出发,从单一要素向多要素综合发展、从指标统计分析向过程动态模拟发展、从单一方法向综合集成方法发展是人口损失及风险定量评估的发展趋势。 相似文献
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Shi Peijun Wang Aihui Sun Fubao Li Ning Ye Tao Xu Wei Wang Jing&#x ai Yang Jianping Zhou Hongjian 《地球科学进展》2016,31(8):775-781
Global climate change featured with warming has created serious challenge to world sustainable development and human security. It has become an important consensus of the international society to assess global change risk at the global scale and carry out tailored governance and risk-based adaptation. National Key Research and Development Program “Study on global change population and economic system risk forming mechanism and assessment” aims at quantitatively predicting future global climate change and population and economic system exposure and vulnerability change, developing global change population and economic system risk assessment model based on complex system dynamics, synthesizing risk assessment model with proprietary intellectual property rights, assess global change population and economic system risk of the near and mid future at the global scale, and compiling the atlas of global change population and economic system risk. The outcomes intend to serve the participation of global risk governance and international climate negotiation, and to provide scientific support to the implementation of international disaster risk reduction strategy. 相似文献
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Proceeding from gaining a knowledge of the structural settings in this area, the authors applied remotesensing techniques and selected multi-temporal image processing to extract information of buried structures inthe Beijing plain area. Good results have been achieved. Through an integrated analysis of remote-sensing, geo-logical, seismic and aeromagnetic data, it is pointed out that there exist two sets of buried fractures of differingtrends and orders-the northeast set and the northwest set. forming a rhombic framework in the images. Thetwo sets of fractures have still been active since the Quaternary. which is of practical signifcance for geologicalstudy, earthquake prevention and planning of urban construction in the area. The results demonstrate that theselection of multi-temporal processing of remote sensing images and the integrated analytic method are impor-tant in the study of buried structures. 相似文献
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山东地面沉降灾害以鲁北平原最为严重,在德州地区的地面沉降已对当地人民的正常生产和生活构成了威胁,并制约了当地经济的可持续发展。通过建立水准测量网络及监测运行,查明了德州市地面沉降的规模和范围,研究成果表明工作区均存在地面沉降现象,截至2010年,德城区由于地下水开采强度大,地面沉降幅度最大,目前地面累计沉降量为-1186．9～-636．9mm,多年平均沉降速率为59．35mm／a,形成了以市区西北部为中心的地面沉降盆地。超量开采深层地下水是造成大规模地面沉降的重要因素。 相似文献