新时期产业区理论视角重构及相关实证研究进展

产业区作为全球区域发展最具活力的"经济—社会"空间,具有带动发展和就业、提升竞争力的作用,备受经济地理学、社会学、管理学等关注。经典产业区理论强调集聚经济、专业化分工、本地制度等内生因素对其成长演化作用,但在经济全球化、区域一体化与技术变革等现实背景以及制度文化、关系、尺度、演化转向等理论背景下,经典产业区理论对产业区外部化、"锁定"效应、空间功能转变等解释的局限性日益凸显。首先,通过国外产业区研究进展综述,发现新时期研究呈现由产业区系统向企业战略、本地根植向全球网络、自发增长向多元化管治、生命周期理论向多重路径依赖等视角转变;其次,对新时期产业区成长演化路径、影响因素及效应的实证研究进行梳理;最后,在总结国内相关研究进展的基础上指出中国未来产业区研究的不足和方向。     

青藏高原人口流入流出时空模式研究

在大数据时代,来自网络的人口迁徙数据,为开展区域间人口流入、流出模式研究提供了强有力的数据支撑。本文基于腾讯日迁徙数据（2015—2018年）,借助时间序列、社交网络和时空统计等分析方法,剖析、挖掘了青藏高原人口流入与流出模式,探讨了青藏高原与国内其他城市间的季节性人口流向和人口互动网络特征。结果表明：① 青藏高原人口流动具有显著的周期性特征,年内呈低—中—中高—高的季节性变化规律;2015至2018年,青藏高原在全国城市流动人口互动网络中的地位持续提升,人口流动量提升了8.2%,网络排名提升了24.5%,中值季、中高值季和高值季相对低值季而言,日均人口流动量依次增高14.2%、26.7%、57.8%;② 青藏高原人口流动方向集中在青藏高原NEE-67.5°至SEE-112.5°的45°扇形区间,并且青藏高原与周边省份的省会城市互动频繁;③ 全国大部分城市与青藏高原人口互动强度持续增强,旅游业起到了关键的推动作用;新疆和田和巴音州、重庆、广安、眉山和河南三门峡与青藏高原间呈现中值季—中高值季升高而高值季下降模式,反映了青藏高原的劳务输入存在季节性变化的规律;吐鲁番、东莞和运城出现高值季下降模式则主要是物资供给关系导致的结果。     

下扬子地区沿江前陆盆地形成的构造控制

华北板块与扬子板块沿大别－胶南造山带的陆－陆碰撞使造 山带侧的扬子板块成为前陆变形带,并在其上发育了沿江前陆盆地。沿江前陆盆地初始继承性发育于下扬子区海退末期残留的陷区,随后于黄马青期受北界滁河断裂与南界江南断裂的对冲控制而成为双向压隐型盆地。     

Spatial pattern and driving factors of migrants on the Qinghai-Tibet Plateau: Insights from short-distance and long-distance population migrants

As one of the most ecologically sensitive issues in the world,migration now plays an important role in population growth on the Qinghai-Tibet Plateau.To promote sustainable development in the world's third pole,it is necessary to investigate population migration on the Plateau.Using 2010 census data,a spatial database of county-level migrants on the Plateau was constructed,and migrants were divided into short-distance and long-distance migrants according to the hukou-registered origins.Measuring migration intensity allowed the spatial pattern of population migration on the Plateau to be ascertained.The driving factors were identified using spatial regression models,and the main conclusions are as follows:(1)In 2010,there were 1.23 million inter-county migrants on the Qinghai-Tibet Plateau,and the overall migration intensity reached 10.50％.There existed significant spatial differences in population migration intensity on the Plateau at that time,and the provincial or prefectural capitals were attractive destinations for migrants.Northwestern Qinghai,which boasted min-ing industries,constituted a significant spatial cluster with a relatively high migration intensity.However,most areas on the Plateau attracted relatively few migrants,especially in western and northern parts of Tibet,which were sparsely populated and uninhabitable.(2)There were 0.95 million short-distance migrants and 0.28 million long-distance migrants.The short-dis-tance migration intensity was 8.14％,while the long-distance migration intensity was only 2.36％.Short-distance migration was the main form of population migration,with a pattern similar to the layout of overall population migration intensity.Only a few county-level units strongly attracted long-distance migrants,which were mostly distributed in northwestern Qinghai.(3)Economic factors were considered fundamental drivers for migrants to live on the Plateau.Destinations with high levels of economic development and more opportunities in non-agricultural jobs proved more attractive for migrants.For short-distance migrants,ur-banization level also proved a considerable driving factor for in-migration.However,long-distance migrants were mainly affected by the job chances of the secondary industry on the Qinghai-Tibet Plateau.     

渤海湾盆地庙西南洼古近纪沟谷特征及对近源碎屑沉积的控制

为了更好地预测低勘探区有利砂体的展布,在综合利用测井、钻井、地震等资料的基础上,对渤海湾盆地庙西南洼古近系的沟谷特征及其对近源碎屑沉积的控制作用进行了研究。结果表明：与郯庐断裂近EW向垂直相交的大型基底断裂在古近纪表现为长期拉张沉降特征,形成区域性的大型沟谷,多控制着次级洼陷的发育;而与郯庐断裂NW向、NNW向相交的派生断层一般处于挤压应力状态,多发育小型挤压断裂型沟谷。这些小型沟谷在缓坡带和陡坡带的表现特征具有明显差异。通过地震反射、地震相、属性分析和钻井资料相结合的手段,识别并确定不同层段的近源碎屑沉积体的展布,对比发现：NE向或近EW向的区域性大型沟谷往往成为陆源碎屑物质的宏观进积方向,规模相对偏小的大型沟谷,对碎屑物质进积方向的控制作用更为明显;而NW向的小型挤压性断沟,只能控制局部陆源碎屑物质的进积,沿着这些小型沟谷进入盆地的方向,往往能够准确寻找到各类近源碎屑沉积体的位置,这将有利于指导庙西南洼古近系的勘探部署。     

Environmental effect and treatment of urban construction in geotechnical engineering

The interact of construction and circumstance becomes more and more obviously, and research on it is essentially urgent. The way to solve it, first it relies on quantifiable evaluation to the effects done by different construction techniques, then, choose related techniques which cause less damage according to the endurance of circumstance.     

Discussion on Nonlinear Behaviors in Reservoir Flood Routing Modeling and Derived Uncertainties

Water Resources - In existing studies, external factors, such as hydrologic, hydraulic, and decision-making uncertainties, have been widely recognized as major risk source in reservoir flood...     

大别造山带地壳结构反演及其动力学意义

大别造山带是全球最大的碰撞造山带之一,三叠纪时期,扬子板块深俯冲至地幔的200km处,经历了超高压变质作用。白垩纪早期,该造山带发生了强烈的伸展和垮塌,以及大规模的后造山地幔源岩浆侵入和火山活动。本研究收集了大别造山带及其邻区(29°~34°N、114°~119°E)的震相资料,采用双差层析成像技术,对大别造山带地壳结构进行反演,研究地壳结构与后造山地幔源岩浆侵入和火山活动之间的关系。结果显示,大别造山带中上地壳存在低速结构,该低速结构可能是熔融的幔源侵入物质,由于俯冲板片断裂,或下地壳/岩石圈发生拆沉,导致软流圈物质上涌至地壳底部、侵入地壳中,形成大别造山带地壳中的低速结构;同时,合肥盆地显示为低速区,可能是受浅部沉积层影响。研究中横切大别山的4条剖面显示,该地区下方存在北向倾斜高速结构,该高速结构可能是襄樊-广济断层,或者是扬子板块向华北板块下方俯冲的遗迹。     

香丽高速公路昌格洛滑坡-隧道工程病害三维数值分析

准确评价滑坡-隧道相互作用及稳定性,采用合理的病害防治方法,对保障公路顺利完工具有重要意义.以香丽高速公路昌格洛滑坡为例,利用现场地质调查、钻探等方法查明了滑坡成因机制以及变形特性,通过数值模拟研究了昌格洛滑坡在天然、降雨和开挖等工况下的空间应力应变特征以及稳定性变化,研究了隧道与所穿越滑坡之间的相互作用,据此提出了相...     

地基激光雷达的玉兰林冠层叶面积密度反演

叶面积密度LAD(Leaf Area Density)是表征冠层内部叶面积垂直分布的重要参数,其分布廓线的准确反演对研究植被碳氮循环、初级生产力和生物量估算等具有重要意义。本文在电子科技大学校内建立实验样区,利用地基激光雷达Leica Scan Station C10和数码相机获取玉兰林高分辨率3维激光点云数据和真彩色影像。利用监督分类将真彩色影像中枝干等非光合组织与叶片分离,再将像素分类信息映射给点云数据,从而提取叶片点云。通过点云数据体元化,并引入2维凸包算法确定垂直方向分层树冠边界,获取激光接触冠层的频率;随机选择不同高度的多个叶片,利用特征值法进行叶片平面拟合,估算出叶倾角,并结合天顶角估算叶倾角校正因子;最后基于体元的冠层分析VCP(Voxel-based Canopy Profiling)方法实现树林冠层LAD反演。结果表明体元化的叶片点云数据能准确确定树林冠层边界和统计接触频率实现LAD反演;反演的LAD变化走势与区域林木冠层叶片垂直分布相吻合,在冠层中下部随着高度的增加叶面积密度也随之增加,在4 m高度处达到最大值1 m2/m3,之后随着高度的增加叶面积密度逐渐降低。根据LAD计算得到的累积叶面积指数LAI为3.20 m2/m2,与LAI-2200实测的叶面积指数相比,相对误差为1.26%。