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991.
Mapping global land system archetypes   总被引:1,自引:0,他引:1  
Land use is a key driver of global environmental change. Unless major shifts in consumptive behaviours occur, land-based production will have to increase drastically to meet future demands for food and other commodities. One approach to better understand the drivers and impacts of agricultural intensification is the identification of global, archetypical patterns of land systems. Current approaches focus on broad-scale representations of dominant land cover with limited consideration of land-use intensity. In this study, we derived a new global representation of land systems based on more than 30 high-resolution datasets on land-use intensity, environmental conditions and socioeconomic indicators. Using a self-organizing map algorithm, we identified and mapped twelve archetypes of land systems for the year 2005. Our analysis reveals similarities in land systems across the globe but the diverse pattern at sub-national scales implies that there are no ‘one-size-fits-all’ solutions to sustainable land management. Our results help to identify generic patterns of land pressures and environmental threats and provide means to target regionalized strategies to cope with the challenges of global change. Mapping global archetypes of land systems represents a first step towards better understanding the global patterns of human–environment interactions and the environmental and social outcomes of land system dynamics.  相似文献   
992.
我国工业碳强度的空间分布及影响因素研究   总被引:2,自引:0,他引:2  
在分析1998—2008年我国工业碳排放和碳强度空间分布特点的基础上,基于省际面板数据,建立回归分析模型,探索地区工业碳强度变化的原因。研究发现,省际工业碳排放量和碳强度的分布存在明显的空间差异;回归分析显示,地区工业总产值在全国所占比例越高,其工业碳强度越低,工业资本有机构成提高有利于降低工业碳强度,但其效应较为微弱,地区工业结构中大中型企业比例增加、重型工业和国有企业比例减少均有利于降低工业碳强度。研究结论的政策含义在于,各地区在发展工业经济的过程中应积极推动工业结构调整以降低工业碳强度,要鼓励企业在市场竞争中壮大规模,防范重工业过度扩张和积极发展非国有经济。  相似文献   
993.
On 23 July 2009, a catastrophic debris flows were triggered by heavy rainfall in Xiangshui gully, Kangding county, southwestern China. This debris flow originating shortly after a rainstorm with an intensity of 28 mm per hour transported a total volume of more than 480×103 m3 debris, depositing the poorly sorted sediment including boulders up to 2-3 m in diameter both onto an existing debris fans and into the river. Our primary objective for this study was to analyze the characteristics of the triggering ra...  相似文献   
994.
To understand the effects of grazing activities and climate change on sandy grassland ecosystems in northern China, a livestock field grazing and enclosure experiment was conducted from 1992 to 2006 in Horqin Sand Land, Inner Mongolia. The results showed that sustained heavy grazing resulted in serious degradation of the vegetation; moderate grazing can maintain vegetation stabilization; and light grazing can promote rapid restoration of degraded vegetation. The livestock productivity was the highest in the moderate grazing grassland, and sustained heavy grazing resulted in rapid decrease of the livestock productivity. Heavy grazing can cause a retrogressive succession of grassland vegetation, whereas moderate and light grazing may promote progressive succession of plant species. The effects of changing climate on succession processes were not significant in the short term; a warm-humid climate is favorable to restoration of degraded vegetation, whereas a sustained warm-drought climate may result in degradation of grassland vegetation. Heavy livestock grazing should be stopped for the sustainable use of grassland; the proper grazing intensity for sandy grassland is two to three sheep or sheep equivalents per hectare in Inner Mongolia.  相似文献   
995.
本文通过区域地震活动性的研究,运用危险性概率计算模型,对工程场地进行了地震危险性分析计算。根据一般工业与民用建筑抗震设计规范50年超越10%概率的要求。确定出场地的基本烈度和最大基岩峰加速度值。  相似文献   
996.
线金厂金矿床是一热液充填型小型金矿。其矿化过程可以划分为4个阶段:①大石英脉形成阶段(伴有少量黄铁矿);②铅锌铜多金属硫化物形成阶段;③以细粒方铅矿为主的金属硫化物阶段;④方解石细脉形成阶段。金矿化主要发生在第二和第三矿化阶段,金与金属硫化物密切共生。矿石中金以自然金和银金矿两种形式存在,仅有少量以类质同象形式存在于金属硫化物中,矿石中的金矿物主要充填于矿物裂隙中和嵌布于矿物晶粒之间,少量被包裹在矿物之中。  相似文献   
997.
Potential curves for theB andX states of I2, NS and PS have been obtained by Rydberg-Klein-Rees (RKR) method. From these RKR potentials, Franck-Condon factors (FCFs) lot the above band systems have been calculated using the best available molecular constants, tested for accuracy on the electronic transition moment (ETM)-r-centroid curve in the case of I2 and used in the study of observed abnormal intensity distribution in some bands of NS. A brief outline of the method used in the calculations of the FCFs is given.  相似文献   
998.
BOOK REVIEWS     
Book Reviewed in this article: Main Street: Northeastern Oregon: The Founding and Development of Small Towns . Barbara Ruth Bailey . Food Politics: The Regional Conflict . David N. Balaam and Michael J. Carey , eds. The International Economy and Industrial Development: Trade and Investment in the Third World . R. Ballance , J. Ansari and H. Singer . Neighborhoods in Urban America . Ronald H. Bayor , ed. The English Heartland . By Robert Beckinsale and Monica Beckinsale . Regional Dimensions of Industrial Policy . Michael E. Bell and Paul S. Lande , eds. Tension Areas of the World . D. Gordon Bennett , ed. Latin America: an Introductory Survey . B. W. Blouet and O. M. Blouet , eds. Integration and Division: Geographical Perspectives on the Northern Ireland Problem . Frederick W. Boal and J. Neville H. Douglas , eds. Energy and Land Use . Robert W. Burchell and David Listokin , eds. Slopes and Weathering . Michael Clarke and John Small . Alaska's Rural Development . Peter G. Cornwall and Gerald Mc Beath , eds. The Politics of Park Design: A History of Urban Parks in America . Galen Cranz . World Congress on Land Policy, 1980, Proceedings . Matthew Cullen and Sharon Woolery , eds. Oregon Divided: A Regional Geography . Samuel N. Dicken and Emily F. Dicken . Urban Food Marketing and Third World Rural Development . T. Scarlett Epstein . South Africa: Spatial Frameworks for Development . T. J. D. Fair . Institutions and Geographical Patterns . Robin Flowerdew , ed. Industrialization of U.S. Agriculture, An Interpretive Atlas . Howard F. Gregor . Planning Theory: Prospects for the 1980s . Patsy Healy , Glen Mc Dougall and Michael J. Thomas , eds. Neighborhood Mobilization: Redevelopment and Response . Jeffrey R. Henig . The American Urban System: A Geographical Perspective . R. J. Johnston . Climate, History and the Modern World . Hubert H. Lamb . Climate and History: Studies in Past Climates and Their Impact on Man . T. M. L. Wigley , M. J. Ingram and G. Farmer . China: Railways and Agricultural Development, 1875–1935 . Ernest P. Liang . A Desirable Energy Future—A National Perspective . Robert S. Livingston , T. D. Anderson , T. M. Besmann , M. Olszewski , A. M. Perry , and C. D. West . Topothesia: Essays Presented to T. S. Ó Máille . B. S. Mac Aodha , ed. Transportation for the Poor: Research in Rural Mobility . Hal S. Maggied . Land Uses in American Cities . Harold M. Mayer and Charles R. Haves . Industrial Organisation and Location . Philip Mc Dermott and Michael Taylor . Human Adaptability: an Introduction to Ecological Anthropology . Emilio F. Moran . Regional Analysis and the New International Division of Labor . Frank Moulaert and Patricia W. Salinas , eds. The Nuclear War Atlas. Victoriaville, Quebec, Canada : Urbanization and Environmental Quality . Isao Orishimo . The Garden of Eden: The Botanic Garden and the Re-Creation of Paradise . John Prest . Earthfire, The Eruption of Mount St. Helens . Charles Rosenfeld and Robert Cooke . Contest for the South China Sea . Marwyn S. Samuels . The Future of the Wetlands: Assessing Visual-Cultural Values . Richard C. Smardon , ed. Tucson: the Life and Times of An American City. C. L. Sonnichsen . The Geography of Multinationals . Michael Taylor and Nigel Thrift , eds. Impact of Marine Pollution on Society . Virginia Tippie and Dana Kester . Reviving the Industrial City: the Politics of Urban Renewal in Lyon and Birmingham . Jerry A. Webman . Andean Reflections: Letters from Carl O. Sauer While on a South American Trip under a Grant from the Rockefeller Foundation, 1942 . Robert C. West , ed. Cartographic Drawing with Computers . P. Yoeli .  相似文献   
999.
在宜宾市珙县五同村布设斜坡地震动监测仪器,采集兴文县3.1级、珙县4.5级及长宁县4.6级地震数据。对监测剖面上1#、2#监测点采集到的珙县余震地震动响应数据进行滤波和校正处理,对比分析震级、高程、方位等因素对斜坡造成的地震响应后认为:1)当地震波的半波长与山体某些特定部位之间的距离接近时,斜坡地形与地震波的波峰产生耦合作用,地形放大效应显著,达到参考点的2.765倍,此处山体更容易产生较大幅度的摇晃,造成山体地质灾害;2)分析珙县4.5级与长宁县4.6级地震得出,当地震波沿特殊部位(如山脊等)传播时,地震加速度及阿里亚斯强度更加显著;3)分析地震加速度变化得出,在地震荷载作用下,随着震级的增大,斜坡的加速度响应也会增大;4)随着高程和震级的变化,监测点的地震加速度和阿里亚斯强度随之变化,高程和震级对斜坡的地震动响应具有放大效应;5)在高程和微地貌的耦合作用下,斜坡地震加速度也具有明显的放大效应。  相似文献   
1000.
北京时间2022年6月1日17时0分四川雅安市芦山县(30.37°N,102.94°E)发生6.1级地震,中国地震台网中心于震后3min发布自动速报结果、震后9min发布正式速报结果,同时联合多家单位启动地震应急产品产出工作,共产出震源参数、历史地震、地震构造、震源机制、余震精定位、推测烈度和震源破裂过程等9类应急产品。结果显示,本次地震发生在龙门山断裂带,位于青藏高原巴颜喀拉地块、岷山构造带、川滇构造带的交汇处;震源机制解表明该地震为一次逆冲型事件;余震精定位结果显示余震展布呈近NE向,与震中区域断裂走向基本一致;烈度速报推测极震区烈度达Ⅸ度,区域面积约2km2,Ⅷ度及以上区域总面积约197km2,涉及四镇一乡。  相似文献   
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