城市地面沉降研究进展及其发展趋势

地面沉降是城市主要地质灾害之一。随着中国城市化进程的加快，地面沉降规模扩大，危害加剧，本文简述了国内外地面沉降概况，对地面沉降的成因、危害、机制、数学模拟、监测、防治等方面的研究进展进行了综合论述，并指出，建设工程性地面沉降，孔隙水运移机制、地下水和地面沉降模型耦合、地面沉降生态-经济-社会影响评估、地下水采灌优化设计、地面沉降系统防治、地面变形高精度监测、城市化建设与地面沉降的相互关系等，是今后城市地面沉降研究的主要方向。     

1980 - 2015年南迦巴瓦峰地区冰川变化及其对气候变化的响应

基于地形图和Landsat TM/OLI遥感影像等数据, 利用目视解译和波段比值法提取1980年、 2000年和2015年南迦巴瓦峰地区冰川空间分布数据, 分析研究区近35年冰川变化, 探讨冰川对气候变化的响应。结果表明： 1980 - 2015年, 南迦巴瓦峰地区冰川面积持续减小并呈加速退缩的趋势, 近35年共减少了（75.23±4.67） km², 占1980年冰川总面积的（25.2±1.6）%, 年平均面积减小率为（0.73±0.05）%。研究区东南坡冰川面积变化速率大于西北坡, 在不同流域、 海拔及朝向上, 冰川变化差异较大。南迦巴瓦峰地区冰川表碛十分发育, 表碛覆盖冰川面积变化率小于裸露冰川, 表碛覆盖对冰川消融具有抑制作用。南迦巴瓦峰地区在气温显著升高的背景下, 虽然降水量有所增加, 但冰川对气温更加敏感, 因气温升高引起冰川消融所带来的物质损失超过降水增加对冰川的补给, 导致南迦巴瓦峰地区冰川普遍萎缩。     

Foreign minorities from developing countries in Madrid

Spain, which has always been a land of emigrants, is currently a centre of attraction for immigrants, as are other countries in Mediterranean Europe. The proportion is not as high as in other countries with a longer tradition of immigration. In this survey we selected the six nationalities which provide the highest numbers of immigrants from the developing world, and which have the greatest racial or cultural contrast to the native population. We analyse their structural features, whether or not immigrants from the same country are collect in the Madrid Metropolitan Area, the recent mobility of the immigrant population, and the evolution of immigration since the Administration carried out a regularization process, as well as Spaniards' opinion of foreign immigrants.     

1980—2017年祁连山水源涵养量时空变化特征

祁连山是中国西北地区十分重要的生态安全屏障,也是当地极为关键的水源涵养区。基于InVEST模型中的产水量模块,对祁连山水源涵养量和时空变化进行了分析并探讨其影响因素。结果表明：祁连山多年平均产水总量和水源涵养总量约为93.03×10⁸ m³和57.83×10⁸ m³。从时间变化来看,水源涵养量呈上升趋势,上升速率约为0.196 mm·a^-1;在空间上呈“东多西少”的分布格局,与年降水量的空间分布大致相同。不同土地利用类型下的水源涵养总量依次为：草地（31.87×10⁸ m³）>林地（16.71×10⁸ m³）>耕地（4.92×10⁸ m³）>其他用地（2.29×10⁸ m³）>建设用地（0.63×10⁸ m³）。降水量与水源涵养量在所有研究时段内均存在显著正相关性。不同时期土地利用类型的变化也会对水源涵养量产生重要影响,研究区草地面积变化对水源涵养量影响较大。根据建立的经验公式并参考已有研究成果,估算得出研究区多年冻土地下冰储量在550 km³以上,在全球气候变暖的背景下,消融趋势明显。研究可为祁连山水资源合理配置和生态系统保护提供参考。     

Trends in the training and employment of geoscientists in Australia from 1967 to 1978

There are now 14 universities and 8 colleges of advanced education in Australia with geology or earth science departments, which comprised 278 professional staff, 2020 undergraduates, and 556 graduate students in 1978. Academic staff, engaged in a wide range of research, represent less than 10 percent of the total number of Australian geoscientists. Almost all non‐academic employers (98 percent of the sample) presently accept a graduate with a B.Sc. (Hons) degree, while 85 percent accept a B.Sc pass degree. About 65 percent of non‐academic geologists work for industry, and the remainder are employed by government surveys and research organisations. Mining and mineral exploration employ 76 percent of the geologists in industry, followed by petroleum exploration with 11 percent. Geologists make up 83 percent of geoscientists in non‐academic employment, the remainder being geophysicists 15 percent and geochemists 2 percent. Information on vacancies available in early 1979 suggests that all the recent graduates would be absorbed by government and industry, and pointed to a resurgence in demand for qualified geoscientists. There has been striking growth in the number of consulting/contracting geological firms, with 65 firms employing 242 geoscientists replying to the 1978 census.     

Urban planning in Rome from 1870 to the first world war

City plans are political documents and changes in the content of plans often reflect changes in the urban political environment. At the time of its annexation into a newly unified Italy in 1870, divergent views abouth the future development of Rome began to emerge. The politically dominant views were expressed in city development olans adopted in 1873 and 1883. These plans stressed eastward expansion and the opening up of the pre-1870 portion of the city with new wider streets. The plans, however, were circumvented by building speculators who developed in areas beyond their boundaries. By the turn of the 20th century a reaction to speculative growth emerged resulting in the adoption of the 1909 plan which stressed core area preservation and peripheral open space protection.     

Aviation,apartheid and sanctions: Air transport to and from South Africa, 1945–1989

The geography of air transport to and from South Africa has been shaped powerfully by the world map of anti-apartheid, sanctions-keeping nations which close their airspace to the Republic's state-owned airline. Re-routering, involving notably the offshore west-African link to Europe, revocation of foreign landing rights and a shrinking airline network have resulted. The economic dependence of the Republic's southern African neighbours on their political adversary has dissuaded them from joining an anti-apartheid air blockade. Likewise, the penalties to black African states of denying overfying, landing and traffic rights to west-European airlines plying the South Africa route have diminished the force of the air embargo.     

珠江三角洲地区近30年降雨变化趋势及其与气溶胶的关系

基于珠江三角洲地区1980~2010年0.5°×0.5°经纬度网格的逐月降水资料,利用Mann-Kendall秩次相关法,对珠江三角洲地区近30年的降雨趋势特征进行了分析。研究表明:珠三角地区2~4月降雨量存在显著下降趋势,而6~9月降雨量有显著的上升趋势。从气溶胶的角度对这种趋势产生的原因进行了分析,针对珠三角地区2~4月和6~9月不同的降雨类型,提出气溶胶物质的增多在一定程度上抑制了2~4月锋面雨的形成,而对6~9月台风雨的产生也存在可能影响的假设,并从降雨机制上进行了解释。     

Urban land consolidation: a review of policy and procedures in Indonesia and other Asian countries

Many Asian mega-cities are growing rapidly and they face formidable urban problems: unplanned squatter settlements, inadequate infrastructure and basic amenities. Smaller Asian urban areas also need badly the provision of basic infrastructure and facilities. However, efforts to improve are often constrained by either nonavailability of suitable land or its exorbitant cost. Strategies such as land consolidation have shown considerable promise. Implementation of the strategy varies from country to country and from project to project. In general, the land consolidation approach is participatory in nature and places emphasis on in situ development with voluntary contribution of private assets by affected households in need of infrastructure and basic services. However, to make any significant impact of the land consolidation strategy on urban development, financial support from multilateral agencies such as the World Bank is necessary. To enable this it is necessary that the policy and implementation procedures fully conform to the objectives of the World Bank's safeguard policies such as OD 4.30 `Involuntary Resettlement'. This study reviews the land consolidation policies and procedures as applied in several Asian countries in general, and in Indonesia in particular. The objective is to identify the gaps that exist between the policy and procedures and that of the objectives of the World Bank's Policy of Involuntary resettlement and to recommend general policy and procedural guidelines for land consolidation projects that would enable financial support from multilateral agencies such as the World Bank. This revised version was published online in July 2006 with corrections to the Cover Date.     

三江源地区1980—2019年积雪时空动态特征及其对气候变化的响应

三江源地区气象站点稀疏,依靠地面台站数据难以反映地面真实积雪情况。利用卫星遥感数据引入重心模型分析了三江源地区1980—2019年4个积雪参数（积雪日数、积雪深度、积雪初日和积雪终日）的时空动态特征,利用Mann-Kendall检验和Sen斜率估计分析了积雪和气候因子的变化趋势,并探究积雪对气候变化的响应。结果表明：1980—2019年三江源地区呈现积雪日数和积雪深度减少、积雪初日推迟、积雪终日提前的变化趋势,而该区域同期的气温和降水量则呈现上升趋势;4个积雪参数重心均呈现出东移趋势,而同期气温重心则呈现西移趋势,气温重心位置西移速率分别是积雪日数和积雪深度重心位置东移速率的6倍和2倍。这表明该区域4个积雪参数以及气候因子的变化趋势具有较强的空间异质性,西部气温升高速率大于东部,导致西部积雪日数和积雪深度减少速率同样大于东部,从而导致气温重心西移而积雪参数重心东移。澜沧江源区积雪日数减少、积雪深度减少、积雪初日推迟以及积雪终日提前的速率最大,其次是长江源区和黄河源区。进一步的相关性分析表明,三江源地区年平均气温的升高是导致积雪日数和积雪深度减少、积雪初日推迟、积雪终日提前的主要影响因子,积雪日数对气温升高响应最敏感,其次是积雪深度、初日和终日;而年降水量与4个积雪参数的相关性均不显著。研究可为三江源地区水资源和生态环境保护提供基础资料和理论依据。     

1980-2017年青海省玉树地区季节冻土变化对气候变暖的响应

利用玉树地区5个气象台站1980-2017年逐月温度和最大冻土深度资料,采用线性趋势、相关及主成分分析等统计方法,对玉树地区最大季节冻土深度在气候变暖背景下的变化规律进行了详细探讨,在分析冻土深度与气温及地表温度变化关系的基础上给出最大冻土深度对温度变化的响应模型。结果表明：1980-2017年玉树地区最大冻土深度以10 cm·（10a）^-1速率呈显著下降趋势,年代际间变化则表现出“减-增-减-增”波动特征,年内对温度变化的响应在时间上存在一定滞后性;最大冻土深度空间分布呈“西北高、东南低”且具有明显的垂直地带性分布;温度变化对局地季节性冻土的影响有一定差异性,除平均最高地温外其余各温度因子与最大冻土深度变化具有良好的一致性,对冻土影响最大的是平均地温,其次为平均最低气温和平均气温,季节性冻土对气温变暖的响应呈现为退化状态。最大冻土深度变化的温度影响因子主成分回归表明,近年来气温和地温的显著升高是玉树地区冻土退化的最大驱动力,响应模型对估算玉树地区未来最大冻土深度的变化具有较高的可信度。     

上海城市地质调查成果在城市规划中的应用(摘要)

城市地质信息作为城市规划的基础资料,是决定城市用地选择的恰当与否、城市的功能组织和城市规划布局合理性的关键,同时对建设工程的经济决策和城市的运营管理等也有一定的影响。     

Assessing disaster needs in megacities: Perspectives from developing countries

Megacities are extreme manifestations of urban complexity that present aid agencies with major disaster assessment challenges. Geographers can contribute to improving megacity disaster assessments by: 1) defining megacity disasters; 2) improving socioeconomic measures of disaster to allow for clearer differentiation of effects among different population sub-groups; 3) specifying criteria for identifying thresholds of disaster and trends in the status of disaster-affected populations; and 4) developing credible data collection and analysis methods appropriate for complex urban environments. In addition, long term research is needed to encourage the formulation of models of megacity life that provide better understanding of human survival under normal conditions of severe adversity.The views expressed herein are entirely those of the author and are not attributable to organizations which have sponsored the author's research.     

1980-2011年全球不同地区冰川物质平衡变化分析

在气候变暖背景下,全球大多数冰川加速退缩,冰川物质亏损严重,呈负平衡增长趋势。利用世界冰川监测服务处（WGMS）最新刊布的物质平衡资料,对全球重点监测冰川的物质平衡现状及结果进行扼要的总结和比较,分析了1980-2011年全球不同地区冰川物质平衡的区域特征、变化过程及总体变化趋势,评估了冰川物质平衡对海平面变化的贡献。结果表明：1980-2011年,全球冰川物质亏损严重,加速退缩,平均减薄了14 m,其中阿尔卑斯山脉及太平洋海岸山脉的退缩尤为明显,平均减薄了30 m左右;各地区冰川的平均物质平衡变化趋势与全球平均趋势基本保持一致,具有典型的纬度地带性分布特征;物质平衡变化过程分为正平衡波动型、负平衡波动型及负平衡持续增长型三类,但总体上处于负平衡持续增长趋势;在全球继续增温的未来,冰川将会继续退缩,物质亏损强度不断增大,负平衡趋势不断增强。冰川物质平衡对海平面上升的贡献呈增大趋势,且与全球气温上升基本上是同步的。     

1980-2010年石羊河流域生态服务类型变化与分析

根据石羊河流域1980年、1990年和2010年三期遥感影像数据,基于GIS技术方法,分析了石羊河流域各县市的土地利用方式变化情况。评估了流域主要生态系统生态服务价值量,分析了30 a来流域生态系统服务价值在时间和空间上的变化。结果表明：过去30 a来,石羊河流域的土地利用变化主要以耕地、草地、未利用土地的变化为主。石羊河流域生态系统服务的总价值呈减少趋势,生态服务价值在空间分布上表现为下游呈增加趋势、中上游表现为减少趋势。流域下游生态服务价值增加的主要原因是流域生态保护与恢复措施取得了显著成效。     

1980-2019年青藏高原积雪深度时空差异性分析北大核心CSCD

积雪是地表特征的重要参数,其对辐射收支、能量平衡及天气和气候变化有重要影响。利用1980-2019年被动微波遥感积雪深度资料对青藏高原积雪时空特征进行分析,在此基础上将高原划分为东部、南部、西部及中部4个区域,并分区域讨论了多时间尺度积雪的变化特征及其与气温、降水的相关关系。结果表明:不同区域积雪深度在不同时间尺度的变化特征存在差异,高原东部积雪深度累积和消融的速率比西部快,南部积雪深度累积和消融速率比中部快。季节尺度上,冬季积雪高原东部最大,中部最小;春季积雪高原东部消融速率最大,西部积雪消融较慢但积雪深度最大;夏季高原西部仍有积雪存在。年际尺度上,各区域积雪深度在1980-2019年均呈现缓慢下降趋势,但东部积雪减少不显著;高原东部积雪深度在1980-2019年呈现出增加-减少-增加-减少的变化,其余3区均呈现出减少-增加-减少-增加-减少的变化。不同区域积雪深度对气温、降水的响应不同,高原东部和中部积雪深度与气温相关性较好;各区域积雪深度与降水呈不显著的正相关关系。     

Mapping of hazard from rainfall-triggered landslides in developing countries: Examples from Honduras and Micronesia

Loss of life and property caused by landslides triggered by extreme rainfall events demonstrates the need for landslide-hazard assessment in developing countries where recovery from such events often exceeds the country's resources. Mapping landslide hazards in developing countries where the need for landslide-hazard mitigation is great but the resources are few is a challenging, but not intractable problem. The minimum requirements for constructing a physically based landslide-hazard map from a landslide-triggering storm, using the simple methods we discuss, are: (1) an accurate mapped landslide inventory, (2) a slope map derived from a digital elevation model (DEM) or topographic map, and (3) material strength properties of the slopes involved. Provided that the landslide distribution from a triggering event can be documented and mapped, it is often possible to glean enough topographic and geologic information from existing databases to produce a reliable map that depicts landslide hazards from an extreme event. Most areas of the world have enough topographic information to provide digital elevation models from which to construct slope maps. In the likely event that engineering properties of slope materials are not available, reasonable estimates can be made with detailed field examination by engineering geologists or geotechnical engineers. Resulting landslide hazard maps can be used as tools to guide relocation and redevelopment, or, more likely, temporary relocation efforts during severe storm events such as hurricanes/typhoons to minimize loss of life and property. We illustrate these methods in two case studies of lethal landslides in developing countries: Tegucigalpa, Honduras (during Hurricane Mitch in 1998) and the Chuuk Islands, Micronesia (during Typhoon Chata'an in 2002).     

The seismic travel-time drop in the Charlevoix region from 1979 to 1980: evidence for aligned saturated cracks in the crust

A significant drop in seismic travel times of up to 1.0% occurred in the Charlevoix region between 1979 and 1980, possibly related to the M = 5.0 (Aug., 1979) earthquake in the vicinity. A travel-time drop of this magnitude could have been produced either by the closing of dry or saturated cracks in the upper crustal material or by the saturation of dry or partly saturated cracks. However, the anisotropy of travel-time changes in this area supports the view that this travel-time drop was caused by the closing of water-saturated aligned vertical cracks in the crustal material. Three different crack directions with respect to north were resolved: 0 ° or 90 ° in the Precambrian rocks underneath the St. Lawrence River, −18° or 72° in the shallow rocks (< 5 km) of the Charlevoix crater, region, and +35° or 125° in the Paleozoic cover rocks. Crack closure would require a decrease in the pore volume of the rocks which would be expected to produce subsidence in the Charlevoix area. Since repeated levellings restrict the vertical crustal motion during this time interval to less than 2 cm, we conclude that either the effective aspect-ratio of cracks is less than 0.0001 or the process of crack closure occurred in a number of unconnected regions. More specifically the crack deformation would have to occur in isolated inclusions less than 1 km in diameter and no deeper than about 6 km. The process of crack closure may have been triggered by the passage of seismic waves from the M = 5.0 earthquake.