隧道围岩强度不均地段塌方成因及其处理方法

由于地质构造作用以及风化作用,工程场地岩体中多存在围岩强度不均地段.在隧道施工过程中就经常遇到软硬岩石交汇而形成的地质条件复杂地段;给隧道的施工带来了很多不利情况,并且也是导致隧道塌方的原因之一.2006年1月,承德韩郭线二级公路工程,喇嘛梁隧道软硬岩石交汇地段由于地下水作用导致围岩风化程度不均,产生软弱结构面并造成了大面积塌方.基于现场的追踪调查与考察,本文详细描述了利用拱顶架设工字钢梁并配合超前注浆小导管的支护方法来处理这类围岩.     

清代地理学家魏源及其《海国图志》──纪念魏源诞生200周年

本文阐述我国清代中期思想家、地理学家魏源的思想及共《海国图志》的特点及历史意义。     

基于区域竞争力对比的新疆旅游资源开发分析

由于资源赋存、区位优势、基础设施、经济发展等方而存在的地域差异,使不同区域在旅游业发展中有不同的业绩和发展潜力。以20纪90年代以来新疆旅游接待量和旅游收入不断增长但旅游目的地地位明显下降为线索,对比研究了新疆的资源禀赋、开发程度、客源市场竞争态等,并调查分析了东南沿海及港澳台地区游客旅游意愿和赴疆游的客源市场潜力。提出区位条件是新疆在现阶段不可抗拒和短期内难以改变的客观因素,必须在现实基础条件下转变思维方式,宏观上以国内远程市场为目标,建立民俗-湖泊-冰川-草原-古迹-沙漠的旅游开发序位；中观上整合近域特殊地理单元内的同构旅游产品以打造品牌；微观上倡导“旅游体验”为核心的管理模式和开发理念。     

The political-economy of Blair’s “New Regional Policy”

The “region” and “regional change” have been elusive ideas within political and economic geography, and in essence require a greater understanding of their dynamic characteristics. Trailing in the backwaters of the devolution to the Celtic nations of Britain, the contemporary era of New Labour’s political-economic ideology, manifest through “third-way” governance in England places the region and its functional capacity into the heart of geographical inquiry. Drawing upon a new regionalist epistemology, this paper seeks to recover a sense of (regional) political economy through a critical investigation of the development and formulation of Blair’s “New Regional Policy” (NRP). I address how New Labour has attempted to marry economic regionalisation on the one hand, and democratic regionalism on the other. This paper specifically questions the wisdom of such a marriage of politically distinct ideologies through a critical investigation of the underlying contradictions of their strategy from both a theoretical and empirical standpoint. Demonstrated both in the North East “no” vote in 2004, and in the post-mortem undertaken by the ODPM Select Committee in 2005, the paper illustrates how a loss of political drive gradually undermined the capacity of devolution to deliver in England. Finally, I argue that through the lens of the NRP we can speculate on some of the wider issues and implications for the study of regional governance.     

Upper mantle structure of the Northern Eurasia from peaceful nuclear explosion data

Several long-range seismic profiles were carried out in Russia with Peaceful Nuclear Explosions (PNE). The data from 25 PNEs recorded along these profiles were used to compile a 3-D upper mantle velocity model for the central part of the Northern Eurasia. 2-D crust and upper mantle models were also constructed for all profiles using a common methodology for wavefield interpretation. Five basic boundaries were traced over the study area: N1 boundary (velocity level, V = 8.35 km/s; depth interval, D = 60–130 km), N2 (V = 8.4 km/s; D = 100–140 km), L (V = 8.5 km/s; D = 180–240 km) and H (V = 8.6 km/s; D = 300–330 km) and structural maps were compiled for each boundary. Together these boundaries describe a 3-D upper mantle model for northern Eurasia. A map characterised the velocity distribution in the uppermost mantle down to a depth of 60 km is also presented. Mostly horizontal inhomogeneity is observed in the uppermost mantle, and the velocities range from the average 8.0–8.1 km/s to 8.3–8.4 km/s in some blocks of the Siberian Craton. At a depth of 100–200 km, the local high velocity blocks disappear and only three large anomalies are observed: lower velocities in West Siberia and higher velocities in the East-European platform and in the central part of the Siberian Craton. In contrast, the depths to the H boundary are greater beneath the craton and lower beneath in the West Siberian Platform. A correlation between tectonics, geophysical fields and crustal structure is observed. In general, the old and cold cratons have higher velocities in the mantle than the young platforms with higher heat flows.Structural peculiarities of the upper mantle are difficult to describe in form of classical lithosphere–asthenosphere system. The asthenosphere cannot be traced from the seismic data; in contrary the lithosphere is suggested to be rheologically stratified. All the lithospheric boundaries are not simple discontinuities, they are heterogeneous (thin layering) zones which generate multiphase reflections. Many of them may be a result of fluids concentrated at some critical P–T conditions which produce rheologically weak zones. The most visible rheological variations are observed at depths of around 100 and 250 km.     

我国入境旅游和经济增长关系分析

文章分析了入境旅游发展的区域差异，并用Granger因果检验来考察入境旅游和各区域经济增长之间是否存在相应的因果关系，Granger因果检验的结果表明在东部地区，入境旅游和经济增长存在单向因果关系。东部地区的入境旅游对区域的经济增长产生显著影响。但是全国和中西部地区的入境旅游与经济增长之间不存在显著的因果关系。类似地，东部地区入境旅游增长是其第三产业增长的Granger原因。但是全国和中西部地区的入境旅游和相应区域第三产业的增长并不存在显著的因果关系。在区域层面上。只有少数区域支持入境旅游是区域GDP增长的Granger原因，它们是东部地区的北京、广东、上海、天津、福建、江苏、浙江、海南和广西；中部地区的黑龙江和湖南以及西部地区的云南和陕西。在这些省区市。入境旅游对区域经济增长产生显著的影响。但总体而言，入境旅游在我国还没有足够的发展。     

Comparative Seismic Risk Studies for German Earthquake Regions on the Basis of the European Macroseismic Scale EMS-98

Within the framework of recent research projects, basic tools for GIS-based seismic risk assessment technologies were developed and applied to the building stock and regional particularities of German earthquake regions. Two study areas are investigated, being comparable by the level of seismic hazard and the hazard-consistent scenario events (related to mean return periods of 475, 2475 and 10000 years). Significant differences exist with respect to the number of inhabitants, the grade and extent of urbanisation, the quality and quantity of building inventory: the case study of Schmölln in Eastern Thuringia seems to be representative for the majority of smaller towns in Germany, the case study of Cologne (Köln) stands for larger cities. Due to the similarities of hazard and scenario intensities, the considerable differences do not only require proper decisions concerning the appropriate methods and acceptable efforts, they enable conclusions about future research strategies and needs for disaster reduction management. Not least important, results can sharpen the focus of public interest. Seismic risk maps are prepared for different scenario intensities recognising the scatter and uncertainties of site-dependent ground motion and also of the applied vulnerability functions. The paper illustrates the impact of model assumptions and the step-wise refinements of input variables like site conditions, building stock or vulnerability functions on the distribution of expected building damage within the study areas. Furthermore, and in contrast to common research strategies, results support the conclusion that in the case of stronger earthquakes the damage will be of higher concentration within smaller cities like Schmölln due to the site-amplification potential and/or the increased vulnerability of the building stock. The extent of damage will be pronounced by the large number of masonry buildings for which lower vulnerability classes have to be assigned. Due to the effect of deep sedimentary layers and the composition of building types, the urban centre of Cologne will be less affected by an earthquake of comparable intensity.     

Regional disparity in the changes of agricultura land use intensity in China during 1980-2002

Based on the cost-benefit data （1980-2002） of farm products and China Agriculture Yearbooks, this paper studies the regional disparity in the changes of the agricultural land use in China during the period 1980-2002 from three aspects such as the degree of intensity, the sown area and the abandoned farmland. The results show that： （1） The degree of intensity of land use in the westena region during 1980-2000 has a strong uptrend, but in the eastern and central regions the degree of intensity descends obviously and has shown a continuous downtrend since 1997. （2） The total sown area shrinks notably in the eastern region, while it enlarges constantly in the western region. （3） The sown area in the eastern, central and western regions has gone through a similar cyclic process： down （1980-1985）-up （1985-1991）-down （1991-1994）-up （1994-1999）-down （1999-2002）. However, there are obvious differences in amplitude variation and tendency among them. The sown area has shrunk in the eastern region and expanded in the central and western regions especially before 1999. （4） The most cases of abandoned farmland are reported in the central region, the second in the eastern region and the least in the western region. The abandonment phenomena chiefly occurred during 1992-1995 in the eastern region, and during 1998-2002 in the central region.