粤港澳大湾区科技基础设施的空间集聚与区域发展效应     

王洋  张虹鸥  岳晓丽 《地理科学进展》2022,41(9):1702-1715

为探究科技基础设施的空间分布特征和区域发展效应,论文以粤港澳大湾区688个科技基础设施为研究对象,以56个县区为基本研究单元,采用平均最近邻距离法分析粤港澳大湾区科技基础设施的空间集聚性与空间差异格局。基于地理探测器从经济水平、居住收入、住房价格、人口学历结构4个方面分析粤港澳大湾区科技基础设施的区域发展效应。结果表明：① 粤港澳大湾区科技基础设施呈现高度的空间集聚性分布,主要集中在广州核心区、深圳南山区和香港南部地区,在县区尺度上具有显著的空间差异和空间极化现象;② 粤港澳大湾区科技基础设施分布对人口学历结构、经济水平、住房价格的空间格局具有显著的正向影响,显示出区域发展效应;③ 不同性质科技基础设施的区域发展效应有所差别,基础研究类科技基础设施对人口学历结构的影响强度最高,应用类科技基础设施对经济水平的影响最为明显。该研究可为粤港澳大湾区创新地理的学术研究提供案例补充,也为粤港澳大湾区科技基础设施的合理布局和优化配置提供决策支撑,具有学术意义和现实价值。  相似文献   

Applying a modified conduit flow process to understand conduit-matrix exchange of a karst aquifer     

Liang-jie Zhao  Yang Yang  Jian-wen Cao  Zhe Wang  Song Luan  Ri-yuan Xia 《China Geology》2022,5(1):26-33

Due to the high heterogeneity and complexity of water flow movement for multiple karst water-bearing mediums,the evaluation,effective development,and utilization of karst water resources are significantly limited.Matrix flow is usually laminar,whereas conduit flow is usually turbulent.The driving mechanisms of water exchange that occur between the karst conduit and its adjacent matrix are not well understood.This paper investigates the hydrodynamic characteristics and the mechanism of flow exchange in dual water-bearing mediums(conduit and matrix)of karst aquifers through laboratory experimentation and numerical simulation.A karst aquifer consisting of a matrix network and a conduit was proposed,and the relationship between the water exchange flux and hydraulic head differences generated from the laboratory experiments was analyzed.Two modes of experimental tests were performed with different fixed water level boundaries in the laboratory karst aquifer.The results indicate that the water exchange capacity was proportional to the square root of hydraulic head differences.The linear exchange term in the conduit flow process(CFP)source program was modified according to experimental results.The modified CFP and the original CFP model experimental data results were compared,and it was found that the modified CFP model had better fitting effects.These results showed that the water exchange mechanism between conduit and matrix is very important for solid-liquid interface reaction,water resource evaluation,and understanding of karst hydrodynamic behavior.  相似文献   

郑州地区沙尘暴天气的气候特征分析   总被引：8，自引：0，他引：8  

张霞  王建玲等 《河南气象》2002,(3):19-20

利用郑州地区各站近40年的气象资料，分析了郑州地区沙尘暴的气候特征，发现郑州地区沙尘暴天气发生的频率自60年代到90年代呈逐渐减少趋势，但从大尺度背景情况分析，全球增暖不可避免，如不科学做好退耕还林、大范围恢复自然植被、有效地改善生态环境，沙尘暴天气将有可能进一步发展。  相似文献   

Failure and flow development of a collapse induced complex landslide: the 2005 Kuzulu (Koyulhisar, Turkey) landslide hazard   总被引：1，自引：0，他引：1  

Işık Yilmaz  Tülay Ekemen  Mustafa Yildirim  İnan Keskin  Gül Özdemir 《Environmental Geology》2006,49(3):467-476

Koyulhisar located in a slope of hilly region and constructed in the side of a mountain along the North Anatolian Fault Zone is frequently subject to landslides. A catastrophic landslide occurred on the morning of 17 March 2005 in the North of the Kuzulu district of Koyulhisar (Sivas, Turkey). This landslide caused widespread loss of life, and damage to buildings, and lifelines. Fifteen people were dead and five were injured, 21 houses and a minaret were covered and damaged severely. The case study presented in this paper describes and analyses the results of the detailed surveys of an interesting landslide in Kuzulu district of Koyulhisar (Sivas, Turkey), based on field and laboratory measurements and monitoring of the slide area. Landslide initiated as a collapse, and developed into debris avalanches in the valley. This phenomenon caused a disaster in the Kuzulu district. The importance of this landslide in particular has been recognized both in terms of its consequence for the people and structures and in terms of its role in allowing an understanding of process and properties of landslide triggered by a collapse in limestone karst. In view of the potential for such events to occur again in this area and environs, understanding of the failure mechanism is very crucial.  相似文献   

地质雷达在岩溶地区岩土工程勘察中的应用   总被引：2，自引：0，他引：2  

蒋家龙  方必量 《安徽地质》2008,18(4):292-296

安徽省沿江及皖南一带石灰岩分布广泛,岩溶发育,由于岩溶溶洞具有隐伏性强、空间分布规律性差、岩溶塌陷难以预测等特点,因此岩溶区岩土工程勘察必需查清岩溶发育规律。本文结合铜陵一带岩溶区岩土工程勘察中几个实例,阐述在岩溶发育区,采用地质雷达结合钻探综合勘察方法,高效准确查清构筑物基础范围内岩溶溶洞发育情况,提高岩溶区勘察效益和勘察进度。  相似文献   

云南石林洞穴发育特征   总被引：2，自引：0，他引：2  

刘宏  周燕 《地球科学进展》2003,18(6):891-898

石林位于滇东喀斯特高原南部,喀斯特极其发育,以发育了典型的石林地形而闻名遐迩,倍受国内外喀斯特学者的关注。洞穴是本区广泛发育分布的一种喀斯特地下形态,类型多样。依据它们的剖面形态、成因和所处的地貌部位差异,将其划分为罅状洞穴、水平洞穴和倾斜洞穴三个类型。洞穴在发育分布上受到区域碳酸盐岩地层分布的控制,表现出洞穴分布的相对集中性、洞穴发育对地层的选择性和洞穴发育的成层性等特征。洞穴发育规模绝大多数为中小型洞穴;洞穴多为现代地下洞河,埋藏浅且多天窗,并且洞穴的发育延伸方向明显受裂隙构造的控制。通过对石林地区喀斯特洞穴发育条件、洞穴发育类型、分布特征和洞穴发育的古地理环境特征分析,论述了石林地区洞穴的发育特征。  相似文献   

利用CHRIS/PROBA数据定量反演草地LAI方法研究     

李新辉  宋小宁  冷佩 《国土资源遥感》2011,(3):61-66

以内蒙古锡林河流域典型草地为研究样区,基于新一代微卫星CHRIS/PROBA高光谱遥感数据,利用双层冠层反射率模型(A two - layer Canopy Reflectance Model,ACRM)定量反演叶面积指数(LAI).首先对高光谱数据进行预处理和统计分析,并结合反演结果对角度信息的敏感性进行分析,确定适...  相似文献   

Leaching evaluation of cement stabilisation / solidification treated kaolin clay     

U.E. John  I. Jefferson  D.I. Boardman  G.S. Ghataora  C.D. Hills 《Engineering Geology》2011,(4):315

Sustainable land management often requires redevelopment of existing and often contaminated Brownfield sites over use of Greenfield or agricultural land. Stabilisation / solidification (S/S) offer a viable remediation option with particular suitability in treating heavy metal contaminants. However, uncertainties over long-term durability and previously cheap landfill disposal costs resulted in limited use in many countries. There is a need to characterise treated material and assess components containment and release, to improve S/S confidence and inform remedial design, using the evaluation of the leaching controlling mechanisms. To improve understanding of key features that will enable improvements to such designs, this paper presents an evaluation of leaching for CEM II stabilised kaolin, using the leaching behaviour of 4 main components—aluminium, silicon, calcium and sulphur. Results show no detrimental implications on chemical durability due to kaolin degradation with hydration under induced alkalinity, with increased formation of stable cementitious minerals. Availabilities for components show that aluminium and silicon had minimal leachability compared to total content, whilst calcium and sulphur show almost total leaching availability. Decreasing calcium and silicon leachability under natural chemical conditions with increased hydration duration supports the increased formation of stable cementitious products with time, using the products of kaolin dissociation.  相似文献   

岩溶大水矿山暗河型导水通道探查与治理技术研究          下载免费PDF全文

田晓明  张勇  仝永庆  褚志远 《山东国土资源》2021,37(6)

对于很多可溶岩地区的矿山而言,采矿过程中往往面临井下突涌水问题,对矿山安全生产和作业人员生命安全造成严重威胁。部分岩溶大水矿山受地层岩性、产状及构造带发育特征等综合影响,往往存在主要的地下水补给通道,发育规模较大且集中的即为暗河型导水通道。通过采用地面物探、钻探勘察、超声测井及连通试验综合探查技术,有效查明某矿F_4断层下盘发育的主要导水通道的分布范围,同时利用地面钻孔投料和注浆技术进行了封堵,彻底切断了矿坑-30m水仓揭露涌水点与区域强岩溶地下含水层的水力联系,大幅减少矿坑排水量。研究成果对于指导类似条件岩溶矿山的涌水治理具有借鉴意义。  相似文献   

南海北部神狐海域现代沉积物正构脂肪酸来源:加权平均碳同位素的建立与应用     

茅晟懿  ;朱小畏  ;孙永革  ;管红香  ;吴能友 《海洋地质前沿》2014,30(8):1-15

对南海北部神狐海域表层沉积物中脂肪酸组分进行了分析,检测到的总正构脂肪酸含量为1.80~10.16μg/g(μg脂肪酸/g干沉积物),碳数分布为C12—C32,呈偶奇优势分布,以C16和C18为主峰碳。将90cm以上层位样品进行归一化,建立加权平均碳同位素讨论正构脂肪酸来源,结果表明,短链脂肪酸(n-C14~18)具有较正的碳同位素组成(加权平均为-26.7‰^-28.2‰),反映了化学自养细菌来源;大部分长链脂肪酸(n-C21~23,nC25,n-C29~32)具有偏负的碳同位素组成(加权平均为-29.6‰^-34.1‰),反映了陆源C3高等植物来源;而另外的长链脂肪酸(n-C24&n-C26~28)和n-C19~20中链脂肪酸(加权平均碳同位素为-26.1‰^-29.3‰)则可能反映了混合来源输入。沉积物75~80cm层位陆源输入和海洋输入含量达到最低,可能和Younger Dryas冷期旋回事件有关。  相似文献