Driving factors and spatiotemporal effects of environmental stress in urban agglomeration: Evidence from the Beijing–Tianjin–Hebei region of China

Environmental stress is used as an indicator of the overall pressure on regional environmental systems caused by the output of various pollutants as a result of human activities. Based on the pollutant emissions and socioeconomic databases of the counties in Beijing–Tianjin–Hebei region, this paper comprehensively calculates the environmental stress index(ESI) for the urban agglomeration using the entropy weight method(EWM) at the county scale and analyzes the spatiotemporal patterns and the differences among the four types of major functional zones(MFZ) for the period 2012–2016. In addition, the socioeconomic driving forces of environmental stress are quantitatively estimated using the geographically weighted regression(GWR) method based on the STIRPAT model framework. The results show that:(1) The level of environmental stress in the Beijing–Tianjin–Hebei region was significantly alleviated during that time period, with a decrease in ESI of 54.68% by 2016. This decrease was most significant in Beijing, Tangshan, Tianjin, Shijiazhuang, and other central urban areas, as well as the Binhai New Area. The level of environmental stress in counties decreased gradually from the central urban areas to the suburban areas, and the high-level stress counties were eliminated by 2016.(2) The spatial spillover effect of environmental stress increased further at the county scale from 2012 to 2016, and spatial locking and path dependence emerged in the cities of Tangshan and Tianjin.(3) Urbanized zones(development-optimized and development-prioritized zones) were the major areas bearing environmental pollution in the Beijing–Tianjin–Hebei region in that time period. The ESI accounted for 65.98% of the whole region, where there was a need to focus on the prevention and control of environmental pollution.(4) The driving factors of environmental stress at the county scale included population size and the level of economic development. In addition, the technical capacity of environmental waste disposal, the intensity of agricultural production input, the intensity of territorial development, and the level of urbanization also had a certain degree of influence.(5) There was spatial heterogeneity in the effects of the various driving factors on the level of environmental stress. Thus, it was necessary to adopt differentiated environmental governance and reduction countermeasures in respect of emission sources, according to the intensity and spatiotemporal differences in the driving forces in order to improve the accuracy and adaptability of environmental collaborative control in the Beijing–Tianjin–Hebei region.     

山东庙岛海峡的峡道动力地貌

在庙岛海峡的动力、沉积、地貌条件比较系统的分析基础上,对庙岛海峡的峡道效应和动力地貌进行了研究,主要包括峡道形成及演变、潮流聚散与侵蚀堆积、涨落潮流歧路与登州浅滩形成、峡道泥沙搬运与沉积效应,结果表明,庙岛海峡具有显著的峡道效应,且峡道东西两段差异明显,对峡道以东的山东半岛北部沿岸海底泥沙运动和沉积具有重要影响。     

电动出租车专用充电场站选址模型研究

近年来随着能源短缺和环境污染问题日益严重,低排放、低噪声、节能环保的电动汽车受到了越来越多的关注.特别在电动出租车领域,我国公共充电设施的规划和建设已迫在眉睫.针对目前电动出租车专用充电站选址研究方面存在的缺少丰富详实的车辆运行数据支撑、未能充分结合出租车的换班特性开展分析和在选址模型构建方面未能充分考虑已建成充电站的...     

舟坝水电站库区某移民新场址的稳定性评价

受拟建马边河舟坝水库蓄水影响,库区部分老场镇将被淹没,前期资料表明,目前规划的某新场址位于一古滑坡体上,因此该滑坡的稳定性对拟建场址移民居住的适宜性有决定性的作用。通过阐述该滑坡的地质条件及成因机制、变形破坏特征,对滑坡进行了定性分析和定量综合评价。结果表明,该古滑坡体在现状及蓄水后均处于整体稳定状态,但局部受场址的开发性影响可能存在局部失稳,建议采取一定防护措施,以满足移民新场址要求。     

新(晚期)构造运动的物质、能量效应与油气成藏

受板块构造背景和深部过程的控制,不同盆地的新(晚期)构造运动具有不同的表现型式,包括伸展和转换-伸展背景下的快速沉降和断裂活化、挤压背景下的强烈隆升和构造掀斜等。新(晚期)构造运动对油气成藏具有强烈的物质效应(对油气成藏要素构成的改造)和能量效应(对成藏动力学环境和过程的影响)。新(晚期)构造运动对油气成藏和分布的影响取决于新(晚期)构造运动期源岩的生排烃状态、新(晚期)构造运动的动力学性质、沉降-抬升的速率、幅度和区域变化及断裂活动程度。建造期(盆地保持沉降、充填状态;源岩处于生、排烃阶段;超压的产生过程仍在进行,超压释放后可得到动态补给)的构造运动可以导致幕式快速成藏,所形成的油气藏属于阶段性充注的原生油气藏,改造期(盆地沉降、充填停止,处于抬升、剥蚀和构造变形状态;源岩生、排烃作用已终止;超压的产生过程已经终止,超压释放后不能得到补给)断裂活化型构造运动可导致已聚集油气的突发性穿层运移和跨层聚集,形成非连续充注的次生油气藏;改造期无断裂活化型构造运动特别是构造掀斜运动可以导致已聚集油气的层内调整,形成有成因联系的调整型油气藏系列。新(晚期)构造运动对油气成藏既可以具有建设性作用、也可以产生调整、改造作用甚至破坏作用。     

中国区域工业全要素生产率的空间计量经济分析

全要素生产率(TFP)是一个国家或地区经济增长质量和技术进步、管理效率提高的重要标志,正确、科学测算TFP对区域经济增长和技术进步及政策研究非常重要。运用空间统计和空间计量经济学的空间自相关Moran指数、空间滞后模型和空间误差模型方法,基于2003年中国大陆31个省、直辖市和自治区的工业企业统计数据,对中国大陆省级区域工业全要素生产率进行了空间计量经济测算分析。结果发现,空间统计与空间计量经济学模型在测算我国省域工业全要素生产率中具有较好效果,利用这种方法测算的2003年中国大陆31个区域全要素生产率的实证结果比较符合工业生产率发展实际;在影响我国省域工业生产率的因素中,工业资本投入是造成工业经济增长率在东中西部地区之间和各个省域之间存在巨大差异的主要原因;劳动生产率水平偏低是制约我国省域工业生产率提高的主要瓶颈因素;2003年我国省域工业生产率增长是由资本和技术共同推动的。     

Tidal effects of a massive spheroidal halo on an inner spheroidal contracting visible body: Application to an evolutionary disk-galaxy model

The effects of the tidal interactions between two coaxial, homogeneous spheroids, one (the “Brigt Component”: B) completely embedded in the other (the “Dark Halo”: D), along a quasi-static contraction, are considered. The aim is to look how the dynamical properties and the final morphology of the B subsystem may be affected by the presence of the D component. Three initial configurations are considered: the quasi-spherical “Dark Halo” D coincides with the “Visible Component” B (case C); D is flatter than B but the two spheroids have the same semiminor axis (case N); no D component is assumed; the “visible” spheroid is single (case S). The application to an evolutionary disk-galaxy model is considered under some simple assumptions: i) in cases C and N the spheroidal halo is massive (mass ratio “dark”/“bright” about ten) and dissipationless. For a mass ratio like this, the tidal interaction of the B component over D turns to be negligible in the course of the contraction; adding to that the lack of dissipation, it appears plausible to take the D component as frozen along the evolution; ii) the degree of anisotropy and the angular momentum of B, J_B, are conserved. The conservation of J_B provides us the time-independent relationship among the key physical quantities and gives the possibility to draw the evolutionary tracks on the plane (axis ratio σ_B, semimajor axis a_B) without any explicit time-scale; iii) the global “star formation rate” is parametrized according to a simple “Schmidt power law” proportional to the square of gas density. At every step of the quasi-static contraction, the structure is determined by the tensor virial theorem extended to a double configuration. The model is very idealized, particularly because there are no available tidal gravitational terms other than for the case of two homogeneous. Nevertheless, the method based on the tensor virial appears powerful to gain insight into the correlations among the physical quantities involved and into their trend along the evolution. One of the main result is a clear indication of a leading role played by the axis ratio of the “Dark-Halo” component which might be, to the extent that this simple picture can be compared with a real galactic system, a possible new physical parameter to be added to mass and angular momentum for separating spirals from S0 galaxies.     

Effects of surface topography on seismic ground response in the Egion (Greece) 15 June 1995 earthquake

The Greek coastal town of Egion on 15 June 1995 was shaken by a strong, small epicentral distance, earthquake that caused heavy damages to buildings and loss of life. The damages were concentrated in the central elevated part of the town whereas the flat coastal region remained almost intact. This non-uniform distribution of damage is studied in this article in terms of surface topography effects by conducting seismic response analyses of a simplified 2-D profile of the town. A dynamic finite element code implementing the equivalent-linear soil behavior (FLUSHPLUS) was used for the analyses and it was found that the step-like topography amplified greatly the intensity of motion without affecting its frequency content. The analyses showed that the motion recorded by an accelerograph installed at the center of the town is in agreement with the computed values; they also indicated a particularly intense amplification close to the crest of the steep slope, where a multi-story RC residential building partially collapsed. In contrast, the level of motion was found to be low at the flat coastal zone of the town where the earthquake damages were insignificant. It is concluded that the characteristic surface topography of the town played an important role in modifying the intensity of base motion.     

Changes of the first Schumann resonance frequency during relativistic solar proton precipitation in the 6 November 1997 event

The variations of the first mode of Schumann resonance are analyzed using data from Kola peninsula stations during the solar proton event of 6 November 1997. On this day the intensive flux of energetic protons on GOES-8 and the 10% increase of the count rate of the neutron monitor in Apatity between 1220 and 2000 UT were preceded by a solar X-ray burst at 1155 UT. This burst was accompanied by a simultaneous increase of the Schumann frequency by 3.5%, and the relativistic proton flux increase was accompanied by 1% frequency decrease. These effects are explained by changes of the height and dielectric permeability of the Earth-ionosphere cavity.     

南京河西地区设计地震动研究

本文根据南京及周围地区的地震环境,采用概率法对南京河西地区某高层公寓工程场址进行了地震危险性分析,采用等效线性化模型考虑场地土的非线性特性的影响,并用一维波动模型进行了场址土层地震反应和场地地震动效应分析,给出了５０年超越概率６３％,１０％和３％的场址基岩和地表的水平向加速度反应谱值加速度。