20 世纪90 年代广州市从业人员的社会空间分异

1990 年以来中国城市的内城区传统工业向郊区外溢,郊区大量劳动密集型国际资本进驻等因素带来城市不同职业从业者的居住空间格局的重构。以1990 年、2000 年广州市“街道层面”的两次人口普查数据为主要数据源,借用经济学中的区位商指标,分析1990~2000 年广州市不同职业从业者的居住空间分异特征,发现工业、低端服务业、高端服务业及政府 机关职员等从业者呈现出差异化的空间分异特征。工业从业者的居住空间从内城区向近郊区、远郊区等转移,低端服务业从业者的居住地一直高度集中于内城区,高端服务业从业者聚居于政府机关附近和高校、科研机构密集区,政府机关职员居住区完全与政府机关相重合。就业地与居住地的临近性是20 世纪90 年代广州城市从业者居住空间最为显著的特征。旧城区产业结构调整、城市空间扩展、郊区国际生产资本进驻、政府为迎合全球化而进行的政策及空间的调整、土地开发与住房商品化以及原有国家事业机关“单位制”居住模式的惯性等成为1990~2000 年广州市不同职业从业者社会空间分异的主要原因。基于区位商的方法来分析不同职业从业者的居住空间分异,为深入解析城市社会空间分异提供了新的研究思路与方法。     

Review of the Research Progress in Global Warming Hiatus

From 1998 to 2012, the warming rate of global mean surface air temperature showed significantly slower than before, which is referred to as the global warming hiatus. The causes and underlying mechanisms of this phenomenon are currently a hot topic of climatic change research. The research significance of global warming hiatus was discussed and relevant research progress was reviewed from two perspectives of external forcings and internal variabilities. In term of external forcings, global warming hiatus is mainly affected by solar activities, volcanic eruptions, aerosols and stratospheric water vapor. With respect to internal variabilities, the warming rate of global mean surface air temperature slowdown is mainly related to the natural variabilities of the Pacific Ocean, the Atlantic Ocean, the Indian Ocean and the Southern Ocean and influenced by the related heat redistribution processes. During the global warming hiatus period, some energy is transferred and restored in the deep ocean so as to modulate the global warming rate, rather than there is a reduction of global total energy in the climate system. In addition, the partially coupled forcing pacemaker model experiment was also reviewed. The pacemaker experiment is a powerful tool for studying the characteristics, causes and underlying mechanisms of the global warming hiatus. Besides, some challenges resulted from the global warming hiatus, including the global energy imbalance, data, simulation and related policy-making were summarized, and future research directions were also discussed.     

Application of multi-channel two-dimensional transient Rayleigh wave exploration in goaf detection

The transient Rayleigh wave exploration has high detection accuracy in shallow exploration. The effect of detection array is comprehensive reflection of the velocity of rock and soilmass. Therefore, the rolling multi-channel transient acquisition system has been adopted in this study, which turns one dimensional transient Rayleigh wave exploration into two dimensions, consequently, the two-dimensional velocity distribution of rock and soil mass under the survey line has been achieved. Through comparing with the shallow seismic reflected wave exploration, the result indicates that the rolling multi-channel transient acquisition system has accurate resolution. Thus, in the process of the shallow reflected wave exploration, if the surface wave has developed, the coalition between the reflected wave exploration and the two-dimensional transient Rayleigh wave exploration should actualize the accuracy of exp loration.     

Application of multi-channel two-dimensional transient Rayleigh wave exploration in goaf detection

The transient Rayleigh wave exploration has high detection accuracy in shallow exploration.The effect of detection array is comprehensive reflection of the velocity of rock and soil mass.Therefore,the rolling multi-channel transient acquisition system has been adopted in this study,which turns one dimensional transient Rayleigh wave exploration into two dimensions,consequently,the two-dimensional velocity distribution of rock and soil mass under the survey line has been achieved.Through comparing with the s...     

Seasonal variation of the barrier layer in the PN section

In this paper, we use the conductivity-temperature-depth (CTD) observation data and a three-dimensional ocean model in a seasonally-varying forcing field to study the barrier layer (BL) in the PN section in the East China Sea (ECS). The BL can be found along the PN section with obviously seasonal variability. In winter, spring and autumn, the BL occurs around the slope where the cold shelf water meets with the warm Kuroshio water. In summer, the BL can also be found in the shelf area near salinity front of the Changjiang (Yangtze) River Dilution Water (YRDW). Seasonal variations of BL in the PN section are caused by local hydrological characteristics and seasonal variations of atmospheric forcing. Strong vertical convection caused by sea surface cooling thickens the BL in winter and spring in the slope area. Due to the large discharge of Changjiang River in summer, the BL occurs extensively in the shelf region where the fresh YRDW and the salty bottom water meet and form a strong halocline above the seasonal thermocline. The formation mechanism of BL in the PN section can be explained by the vertical shear of different water masses, which is called the advection mechanism. The interannual variation of BL in summer is greatly affected by the YRDW. In the larger YRDW year (such as 1998), a shallow but much thicker BL existed on the shelf area. Supported by National Basic Research Program of China (973 Program, No. 2005CB422303 and 2007CB411804), the Key Project of the International Science and Technology Cooperation Program of China (No. 2006DFB21250), the “111 Project” of the Ministry of Education (No. B07036), the Program for New Century Excellent Talents in University, China (No. NECT-07-0781)     

近年来中国城市化与全球环境变化研究述评

城市化与全球环境变化研究已引起全球范围学者的广泛重视.改革开放以来,我国城市化水平不断上升,城市化质量不断提高,同时城市化也产生资源过度消耗、环境污染、生境退化等诸多问题,尤其是近年来气候异常、自然灾害频发等使学术界更加重视城市化与全球环境变化的研究,开始思考人类应该以怎样的方式处理人地关系的问题.文章在分析国内学者关于城市化与全球环境变化研究的界入视角与关注重点的基础上,对国内研究从研究内容、方法与尺度3方面进行评价,并指出从人文地理学角度出发的3个研究议题,包括城市生计与全球环境变化、城市系统脆弱性与全球环境变化以及城市管治与全球环境变化.     

小清河分洪区洪水演进的数值模拟

本文应用数值模拟方法,对永定河中游的小清河分洪区内分洪时的洪水演进过程进行了模拟计算,在此基础上编制了该分洪区的洪水风险图,并研究了减少分洪区内生命财产损失的若干对策。实践证明,这种成果可作为防洪决策的基础,目前已被某些地区采用。     

中心城市信息来源、加工和扩散研究──以《广州日报》为例

本支以信息服务业中的报纸业为研究对象，描述《广州日报》信息来源、加工和扩散的过程，分析其时空变化特征．《广州日报》信息来源的渠道，各渠道的相对重要性，信息的收集和加工的技术效率，信息产品的质量，信息扩散的规模、方式和过程都发生了很大变化，呈现出整体提高的趋势．文章还分析了《广州日报》信息扩散的空间变化特征，并对这些特征的形成因素进行了确定。文章最后还对本案例研究的理论意义进行了讨论，指出；在多个微观案例研究的基础上进行宏观概括将更接近事情的真相。