大运河环境景观与变化分析

基于第一次地理国情普查成果,结合高分辨率遥感影像、遗产保护区划图、遗产要素统计信息,获取、分析了大运河申遗之前(2009年为主)、申遗成功当年(2014年)、申遗成功一年之后(2015年)三个时点的环境景观及变化信息,为大运河调查、评估、规划、管理、监测提供理论和地理信息支撑.通过本研究探索,对地理国情普查成果有效转化应用起到很好的示范作用,并为其他世界文化遗产和不可移动文物监测提供了有效借鉴.     

威海市海岸带地质环境承载力综合评价研究

该文在威海市海岸带综合地质调查项目的基础上,根据陆域和海域不同的地质环境条件,分别进行了地质环境承载力综合评价。陆域选取了3个一级评价因子和13个二级评价因子建立地质环境承载力评价指标体系,利用层次分析法取得各评价因子权重,再利用模糊数学综合指数法进行了综合评价。海域选取了海底沉积物重金属污染、海底沙坡沙脊、浅层气、浅埋基岩和埋藏下切谷等5个评价因子,采用叠加法进行了综合评价。最终,将研究区地质环境承载力划分为强区、较强区、一般区、较弱区等4类。研究区陆域地质环境承载力相对较强,占总面积的67.67%;其次为一般区,占总面积的31.67%;较弱区零星分布,仅占总面积的0.66%。近海地质环境承载力总体较强,一般区主要分布在威海湾西部,较弱区分布在威海湾以北的广阔海域。     

基于ANUSPLIN软件的逐日气象要素插值方法应用与评估

气象要素是资源、环境、灾害以及全球变化等领域研究的数据基础,格点化数据在未来研究应用中显得日益重要。本文基于中国境内667个基本和基准地面气象观测站点的基本气象资料,使用ANUSPLIN专用气候插值软件对1961-2006年逐日气温、降水进行插值,并利用未参与插值的全国1667个加密站点对插值结果的准确性进行检验,同时与反向距离权重法和普通克吕格法等插值方法的结果进行对比。结果表明,利用667个站点使用ANUSPLIN软件进行逐日平均气温插值有92.0%的误差在2.0℃以内,75.0%的误差在1.0℃以内,0.9%的误差在5.0℃以上,平均绝对误差为0.8℃;对逐日降水进行插值,75.0%的误差小于5.0mm,85%的误差小于10.0mm,平均绝对误差为6.4mm,误差大小与降水量呈现出正相关性,对局地强降水的插值效果不好,这可能与参与局部拟合插值的样本数太少有关;同时,夏季的温度插值误差小于冬季,而冬季的降水误差小于夏季。将ANUSPLIN的局部薄盘样条插值结果分别与反向距离权重法和普通克吕格法的插值结果进行对比,显示ANUSPLIN软件的插值误差最小。结果同样表明,适当增加站点数量和提高DEM精度可进一步提高ANUSPLIN软件的插值精度。     

Barriers to movement: Modelling energetic costs of avoiding marine wind farms amongst breeding seabirds

Proposals for wind farms in areas of known importance for breeding seabirds highlight the need to understand the impacts of these structures. Using an energetic modelling approach, we examine the effects of wind farms as barriers to movement on seabirds of differing morphology. Additional costs, expressed in relation to typical daily energetic expenditures, were highest per unit flight for seabirds with high wing loadings, such as cormorants. Taking species-specific differences into account, costs were relatively higher in terns, due to the high daily frequency of foraging flights. For all species, costs of extra flight to avoid a wind farm appear much less than those imposed by low food abundance or adverse weather, although such costs will be additive to these. We conclude that adopting a species-specific approach is essential when assessing the impacts of wind farms on breeding seabird populations, to fully anticipate the effects of avoidance flights.     

Semi‐active tuned mass damper building systems: Application

Seismic performance attributes of multi‐story passive and semi‐active tuned mass damper (PTMD and SATMD) building systems are investigated for 12‐story moment resisting frames modeled as ‘10+2’ stories and ‘8+4’ stories. Segmented upper portion of the stories are isolated as a tuned mass, and a passive viscous damper or semi‐active resetable device is adopted as energy dissipation strategy. The semi‐active approach uses feedback control to alter or manipulate the reaction forces, effectively re‐tuning the system depending on the structural response. Optimum tuned mass damper control parameters and appropriate matching SATMD configurations are adopted from a companion study on a simplified two‐degree‐of‐freedom system. Statistical performance metrics are presented for 30 probabilistically scaled earthquake records from the SAC project. Time history analyses are used to compute response reduction factors across a wide range of seismic hazard intensities. Results show that large SATMD systems can effectively manage seismic response for multi‐degree‐of freedom systems across a broad range of ground motions in comparison to passive solutions. Specific results include the identification of differences in the mechanisms by which SATMD and PTMD systems remove energy, based on the differences in the devices used. Additionally, variability is seen to be tighter for the SATMD systems across the suites of ground motions used, indicating a more robust control system. While the overall efficacy of the concept is shown the major issues, such as isolation layer displacement, are discussed in detail not available in simplified spectral analyses, providing further insight into the dynamics of these issues for these systems. Copyright © 2009 John Wiley & Sons, Ltd.     

Modelling landscape evolution

Geomorphology is currently in a period of resurgence as we seek to explain the diversity, origins and dynamics of terrain on the Earth and other planets in an era of increased environmental awareness. Yet there is a great deal we still do not know about the physics and chemistry of the processes that weaken rock and transport mass across a planet's surface. Discovering and refining the relevant geomorphic transport functions requires a combination of careful field measurements, lab experiments, and use of longer‐term natural experiments to test current theory and develop new understandings. Landscape evolution models have an important role to play in sharpening our thinking, guiding us toward the right observables, and mapping out the logical consequences of transport laws, both alone and in combination with other salient processes. Improved quantitative characterization of terrain and process, and an ever‐improving theory that describes the continual modification of topography by the many and varied processes that shape it, together with improved observation and qualitative and quantitative modelling of geology, vegetation and erosion processes, will provide insights into the mechanisms that control catchment form and function. This paper reviews landscape theory – in the form of numerical models of drainage basin evolution and the current knowledge gaps and future computing challenges that exist. Copyright © 2010 John Wiley & Sons, Ltd.     

The topographic imprint of a transient climate episode: the western Andean flank between 15·5° and 41·5°S

Mountain‐range topography is determined by the complex interplay between tectonics and climate. However, often it is not clear to what extent climate forces topographic evolution and how past climatic episodes are reflected in present‐day relief. The Andes are a tectonically active mountain belt encompassing various climatic zones with pronounced differences in rainfall, erosion, and glacier extent under similar plate‐boundary conditions. In the central to south‐western Andes, climatic zones range from hyperarid desert with mean annual rainfall of 5 mm/a (22·5°S) to year‐round humidity with 2500 mm/a (40°S). The Andes thus provide a unique setting for investigating the relationship between tectonics, climate, and topography. We present an analysis of 120 catchments along the western Andean watersheds between 15·5° and 41·5°S, which is based on SRTMV3‐90m data and new medium‐resolution rainfall, tropical rainfall measurement mission (TRMM) dataset. For each basin, we extracted geometry, relief, and climate parameters to test whether Andean topography shows a climatic imprint and to analyze how climate influences relief. Our data document that elevation and relief decrease with increasing rainfall and descending snowline elevation. Furthermore, we show that local relief reaches high values of 750 m in a zone between 28°S to 35°S. During Pleistocene glacial stages this region was affected by the northward shifting southern hemisphere Westerlies, which provided moisture for valley‐glacier formation and extended glacial coverage as well as glacial erosion. In contrast, the southern regions between 35°S to 40°S receive higher rainfall and have a lower local relief of 200 m, probably related to an increased drainage density. We distinguish two different, climatically‐controlled mechanisms shaping topography: (1) fluvial erosion by prolonged channel‐hillslope coupling, which smoothes relief, and (2) erosion by valley glaciers that generates relief. Finally, Our results suggests that the catchment‐scale relief of the Andes between 28°S to 35°S is characterized by a pronounced transient component reflecting past climatic conditions. Copyright © 2010 John Wiley & Sons, Ltd.     

灾害风险科学与灾害易损性研究实践

在收集、整理和编译国外有关论坛和研讨会资料的基础上,给出了目前国际风险科学研究的动态,综述了地震灾害风险评估和减轻地震易损性方面的研究进展,介绍了目前有关国家的地震灾害风险减轻的理论研究和减灾计划与行动。     

兰州市南北两山生态建设效应的遥感监测

利用1999年Landsat ETM+、2005年Landsat TM卫星影像和2009年“环境与灾害监测预报小卫星”影像提取兰州南北两山地区三期土地利用数据,将景观生态学的理论与兰州南北两山环境绿化工程的实际相结合,运用GIS分析、景观指数计算及数理统计等多种方法,对兰州南北两山地区1999—2009年的土地利用与景观格局动态变化进行分析。结果表明,10 a来兰州南北两山的土地利用变化主要表现为林地和建设用地的增加,草地和农田的减少;景观格局趋于破碎化,多样性增大,景观结构趋于多样化和均匀化。驱动力分析表明,人类活动和政策因素是导致该区土地利用和景观格局变化的主要原因。     

樟子松固沙林带间植被恢复及其对林草界面作用的响应

调查了海拉尔市巴音岱林场不同分布格局、不同带间距的人工樟子松林带内植被恢复过程及物种多样性的差异,分析了林草界面生态学效应,研究了林草界面对带间植被自然恢复的作用。结果表明,宽的带间距带内物种多样性和生物量变化曲线出现了两个高峰,而窄的带间距带内只有一个高峰,说明该地区林带之间距离不应小于12 m;当林带之间距离为16~28 m时草本物种多样性出现最大值。植被恢复效果表现为带间距12 m差于带间距24 m,虽然都差于天然植被,但边际效应大大地加速了群落演替的进程。研究区樟子松林草界面边缘效应影响域为20 m, 其小尺度范围内生境异质性也很明显。行带式造林带间距离不应大于40 m,超出边缘效应影响域不利于带间植被恢复。