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Dynamics of sea-ice biogeochemistry in the coastal antarctica during transition from summer to winter

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Geoscience Frontiers 2017年第3期8卷 507-516页

作者： Suhas Shetye Babula Jena Rahul Mohan National Institute of Oceanography Donapaula Goa 403004 India National Centre for antarctic and Ocean Research Headland Sada Goa 403 804 India

The seasonality of carbon dioxide partial pressure （pC02）, air-sea CO2 fluxes and associated environ- mental parameters were investigated in the antarctic coastal waters. The in-situ survey was carried out from the austral summer till the onset of winter （January 2012, February 2010 and March 2009） in the Enderby Basin. Rapid decrease in pCO2 was evident under the sea-ice cover in January, when both water column and sea-ice algal activity resulted in the removal of nutrients and dissolved inorganic carbon （DIC） and increase in pH. The major highlight of this study is the shift in the dominant biogeochemica/ factors from summer to early winter. Nutrient limitation （low Si/N）, sea-ice cover, low photosynthetically active radiation （PAR）, deep mixed layer and high upwelling velocity contributed towards higher pCO2 during March （early winter）. CO2 fluxes suggest that the Enderby Basin acts as a strong CO2 sink during January （-81 mmol m-2 d 1）, however it acts as a weak sink of CO2 with -2.4 and -1.7 mmol m 2 d-1 during February and March, respectively. The present work, concludes that sea ice plays a dual role towards climate change, by decreasing sea surface pCO2 in summer and enhancing in early winter. Our observations emphasize the need to address seasonal sea-ice driven CO2 flux dynamics in assessing antarctic contributions to the global oceanic CO2 budget.

关键词： pCO2 fluxes Upwelling antarctica Sea-ice

Enduring legacy of coal mining on the fungal community in a High Arctic soil after five decades

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Pedosphere 2022年第5期32卷 698-706页

作者： Dorsaf KERFAHI Kevin K.NEWSHAM Ke DONG Hokyung SONG Mark TIBBETT Jonathan M.ADAMS School of Natural Sciences Department of Biological SciencesKeimyung UniversityDaegu 42601(Republic of Korea) NERC british antarctic survey Madingley RoadCambridge CB3 OET(UK) Department of Life Science Kyonggi UniversitySuwon-si 16227(Republic of Korea) School of Earth and Environmental Sciences The University of ManchesterManchester M139PL(UK) Department of Sustainable Land Management&Soil Research Center School of AgriculturePolicy and DevelopmentUniversity of ReadingReading RG66AR(UK) School of Geographic and Oceanographic Sciences Nanjing UniversityNanjing 210008(China)

Mineral extraction is known to affect soil fungi in polar environments,but it is unknown how long these effects ***,by amplifying the internal transcribed spacer regions of rRNA genes in soil fungi,we compared soil fungal community in intact natural tundra with that in a nearby former coal mining area,abandoned 52 years previously,on Svalbard in the High *** with those in intact tundra,soils in the former mining area were more acidic and had lower plant *** of similar diversity in the two areas,the fungal community was dominated by Basidiomycota in the intact tundra,but by Ascomycota in the former mining *** genera formed a major part of the tundra community,but were notably less abundant in the mining *** principal variation among samples was soil ***,network connectivity analysis indicated that the fungal community in the former mining area had greater network connectivity than that in the tundra ***,the ecosystem in the former mining area has made only limited recovery towards the natural tundra state even after more than five *** is unclear whether the recovery of the fungal community is limited more by the low primary productivity,slow migration of fungi and plants,or slow changes in soil *** findings emphasize the susceptibility of polar ecosystems to disturbance,given their particularly slow recovery back towards the natural state.

关键词： abandoned mining site ectomycorrhizal fungi intact tundra mine tailings mineral extraction polar ecosystem recovery

Remembering,Forgetting,and Absencing Disasters in the Post-disaster Recovery Process

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International Journal of Disaster Risk Science 2020年第3期11卷 287-299页

作者： Charlotte Monteil Jenni Barclay Anna Hicks Lancaster Environment Center Lancaster UniversityBailrigg LAI 4YWUK School of Environmental Sciences University of East AngliaNorwich NR47TJUK Edinburgh Office British Geological SurveyEdinburgh EH 144BAUK

Sustainable post-disaster recovery implies learning from past experience in order to prevent recreating forms of *** construction supports both the healing process and redevelopment ***,memory of disaster results from the balance between remembering,forgetting,and absencing elements of the disaster,and can be both a tool and an obstacle to sustainable *** explore here how collective memory is built in a post-disaster context to respond to the needs of this critical period,and how it shapes *** ethnographic study,conducted between 2015 and 2017,explores the recovery processes in Montserrat,a small Caribbean island affected by an extended volcanic crisis from 1995 to *** this study does not give tangible solutions for disaster risk reduction in a post-disaster context,it highlights potential obstacles for learning from a disaster and how they may be *** argue that it is crucial to acknowledge evolving collective memory in order to implement effective measures for preserving and sharing a shared understanding of disaster across generations and social groups in a way that supports disaster risk *** also maintain that acknowledging the dilemma faced by authorities and disaster management agencies during a period of conflicting needs may encourage the reconsideration of risk framing,and hence reveal how to improve implementation of disaster risk reduction measures.

关键词： Absencing risk information Disaster remembering Forgetting processes Montserrat Post-disaster recovery

OneGeology:Making Geological Map Data for the Earth Accessible

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地学前缘 2009年第S1期16卷 278-278页

作者： Chloe Wrighton Catherine Pennington british Geological survey Kingsley Dunham Centre

OneGeology is an international initiative of the geological surveys of the world and a flagship project of the"International Year of Planet Earth".Its aim is to create a digital geological map of the world and to make it available via the web to *** target scale is l:l million but the project is pragmatic and accepts a range of scales and the best available *** date, 102 countries are participating in the project and。

关键词： global geology map geological surveys OneGeology

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人类土地利用的历史变化对气候的影响

科学通报 2007年第12期52卷 1436-1444页

作者：石正国延晓冬尹崇华王召民中国科学院大气物理研究所东亚区域气候-环境重点实验室 british antarctic survey Cambridge CB30ETUK

通过MPM-2——一个中等复杂程度的地球系统模式（EMIC），对近1000a来土地利用对气候的影响进行了模拟，主要评估人类土地利用造成的陆面覆盖变化的生物地球物理作用．以耕地面积的变化来近似森林砍伐的动态过程，近300a来大面积的森林... 详细信息

通过MPM-2——一个中等复杂程度的地球系统模式（EMIC），对近1000a来土地利用对气候的影响进行了模拟，主要评估人类土地利用造成的陆面覆盖变化的生物地球物理作用．以耕地面积的变化来近似森林砍伐的动态过程，近300a来大面积的森林砍伐使全球变冷了0．09～0．16℃，而北半球年均温降低了0．14～0．22℃，尤其在春季更为显著．为了将人类土地利用和其他强迫进行比较，还模拟了气候系统对温室气体浓度变化的响应．目前，植树造林正逐渐成为陆地碳“捕获”以及调节区域气候状况的重要手段，表明在进行气候变化研究时，人类土地利用造成的陆面覆盖变化的生物地球物理机制是不可被忽略的．

关键词：气候变化辐射强迫土地利用森林砍伐气候-生物圈相互作用

Landslide Research at the british Geological survey:Capture,Storage and Interpretation on a National and Site-Specific Scale

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地学前缘 2009年第S1期16卷 67-67页

作者： Catherine Pennington british Geological survey Kingsley Dunham Centre

The british Geological survey(BGS)is the national geological agency for Great Britain and provides geoscientific information to government, other institutions and the general *** research at BGS is carried out through... 详细信息

关键词： landslide national mapping National Landslide Database

Mineral Resource Safeguarding Policy and Practice in England

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地学前缘 2009年第S1期16卷 164-164页

作者： C.E.Wrighton E.J.Bee british Geological survey Kingsley Dunham Center

The land use planning system in England is governed by legislation which is implemented through national policy and incorporated into development *** and local development plans form the basis for the planning decisions made by planning *** density in England is very high and competition for land use is *** the introduction of Minerals Policy Statement 1(MPS1)

关键词： sustainable minerals planning policy safeguarding

Lid tectonics-Preface

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Geoscience Frontiers 2018年第1期9卷 1-2页

作者： Craig O’Neill NickM.W.Roberts Macquarie Planetary Research Centre Department of Earth and Planetary ScienceMacquarie UniversitySydneyNSW 2019Australia NERC Isotope Geosciences Laboratory British Geological SurveyNottinghamNG12 5GGUK

The idea that plate tectonics may not have operated deep in Earth’s Precambrian past has a long legacy. What predated plate tectonics is unknown, and advances in data - from geochemical,geological and tectonic, to paleomagnetic, as well as modelling approaches,and planetary science, have the potential to contribute significantly to the debate. To contrast with the activity of plate tectonics,in this issue we use the term ‘lid tectonics’ to encapsulate a variety of envisaged regimes e from stagnant, sluggish, plutonicsquishy,or heat pipe - which are characterized by comparatively subdued tectonic *** special issue of Geoscience Frontiers aims to present a snapshot of current research in the field of lid-tectonics - from detailed field interpretations, to global conceptual models, data compilations,and insights from simulations, and provide unique insights into both the Precambrian Earth, and the dynamics of lid-tectonics.

关键词： plate tectonics Earth’s Precambrian

Boundary Integral Modelling of Elastic Wave Propagation in Multi-Layered 2DMedia with Irregular Interfaces

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Communications in Computational Physics 2008年第1期3卷 52-62页

作者： Enru Liu Zhongjie Zhang Jianghua Yue AndyDobson Department of Geophysics China University of Mining and TechnologyXuzhou221008China british Geological survey West Mains RoadEdinburgh EH93LAScotlandUK Institute of Geology and Geophysics Chinese Academy of SciencesBeijingChina.

We present a semi-analytic method based on the propagation matrix formulation of indirect boundary element method to compute response of elastic(and acoustic)waves in multi-layered media with irregular *** method works recursively starting from the top-most free surface at which a stress-free boundary condition is applied,and the displacement-stress boundary conditions are then subsequently applied at each *** basic idea behind this method is the matrix formulation of the propagation matrix(PM)or more recently the reflectivity method as wide used in the geophysics community for the computation of synthetic seismograms in *** reflected and transmittedwave-fields between arbitrary shapes of layers can be computed using the indirect boundary element method(BEM,sometimes called IBEM).Like any standard BEM,the primary task of the BEM-based propagation matrix method(thereafter called PM-BEM)is the evaluation of element boundary integral of the Green’s function,for which there are standard method that can be *** addition,effective absorbing boundary conditions as used in the finite difference numerical method is adapted in our implementation to suppress the spurious arrivals from the artificial boundaries due to limited model *** our knowledge,such implementation has not appeared in the *** present several examples in this paper to demonstrate the effectiveness of this proposed PM-BEM for modelling elastic waves in media with complex structure.

关键词： Boundary element method wave propagation seismology scattering.