大连城市空间意象分析

近年来,城市空间意象研究开始在我国城市地理学界逐渐兴起。通过问卷调查、图片辨认和认知地图调查对大连市微观空间情景和宏观空间结构意象进行研究,在国内首次将因子分析方法应用于微观空间情景的意象偏好分析,并运用均值比较检验及方差分析研究了年龄、性别、学历等属性对个人辨认照片数目及意象范围的影响。研究结果表明：大连市总体可意象程度较高;微观空间情景的意象受其功能、区位、使用者、自然环境以及建筑本体的影响;宏观空间结构意象是以道路为主要支撑,以居住区与商业区为背景,人口集散地与特色建筑点缀其中的立体框架结构;意象区域是以中部为主轴向东西两个方向辐射,并且主要集中在市中心、商业区及风景旅游区;由于受到年龄、性别、学历的影响,个人的意象范围大小存在一定的差异。在此研究基础上,对大连市旅游规划及城市规划提出了相应的建议。     

海上距离元胞自动机分析法

针对障碍存在情况下距离变换研究较少的问题,提出了一种基于元胞自动机的绕障欧氏距离变换方法。以南海为例,基于海陆分布数据和目标点数据,以最短绕障路径长度为元胞状态,设计了包含距离算子的元胞状态转换规则。通过元胞自动机模拟距离扩散计算过程,得到绕障距离变换结果,并分析了绕障效果和精度。结果表明:本文方法动态直观地展示了绕障距离变换过程,能够自动计算绕过障碍的最短距离;具有更新机制,能够根据邻域的变化修正状态值;为绕障距离变换问题提供了一种近似的解决途径,错误率低于3.96%,可应用于航线设计、海上救助等领域。     

IRIS DMC的数据服务

介绍了IRISDMC的数据来源、数据服务内容和数据请求工具,这对于较好地使用其数据资源及做好中国的地震数据服务工作有一定的意义。     

Organic biomarkers in the twilight zone—Time series and settling velocity sediment traps during MedFlux

The transfer of material through the twilight zone of the ocean is controlled by sinking particles that contain organic matter (OM) and mineral ballast. During the MedFlux field program in the northwestern Mediterranean Sea in 2003, sinking particulate matter was collected in time series (TS) and settling velocity (SV) traps and analyzed for amino acids, lipids, and pigments (along with ballast minerals) [Lee, C., Armstrong, R.A., Wakeham, S.G., Peterson, M.L., Miquel, J.C., Cochran, J.K., Fowler, S.W., Hirschberg, D., Beck, A. Xue, J., 2009b. Particulate matter fluxes in time series and settling velocity sediment traps in the northwestern Mediterranean Sea. Deep-Sea Research II, this volume [doi:10.1016/j.dsr2.2008.12.003]]. The goal was to identify how organic chemical compositions of sinking particles varied as a function of their in-situ settling velocity. The TS record was used to define the biogeochemical character and temporal pattern in flux during the period of SV trap deployment. Temporal variations in organic and mineral compositions are consistent with particle biogeochemistry being driven by the seasonal succession of phytoplankton. Spring diatom bloom conditions led to a high flux of rapidly sinking aggregates and zooplankton fecal matter; summer oligotrophy followed and was characterized by a higher proportion of slowly sinking phytoplankton cells. Bacterial degradation is particularly important during the low-flux summer period. Settling velocity traps show that a large proportion of particulate organic matter sinks at 200–500 m d⁻¹. Organic compositions of this fast-sinking material mirrors that of fecal pellets and aggregated material that sinks as the spring bloom terminates. More-slowly sinking OM bears a stronger signature of bacterial degradation than do the faster-sinking particles. The observation that compositions of SV-sorted fractions are different implies that the particle field is compositionally heterogeneous over a range of settling velocities. Thus physical and biological exchange between fast-sinking and slow-sinking particles as they pass down the water column must be incomplete.     

北部湾盆地海中凹陷流三段沉积相研究及其意义

以频率、连续性、振幅、几何形态为划分依据,将海中凹陷流三段划分为6类地震相。通过区域沉积背景研究,分析其可能发育的沉积相类型,并根据其自身的地震反射特征和浅层有井层段沉积相分析,进行了地震相到沉积相的转化。海中凹陷流三段发育的沉积相类型主要有辫状河-冲积平原、滨浅湖、辫状河三角洲、近岸水下扇和半深湖。研究的意义在于证实了海中凹陷流三段储集层发育,同时推测凹陷深处发育的半深湖和大面积分布的浅湖可能发育大套湖相烃源岩。     

Changes in fine sediment size distributions due to interactions with streambed sediments

In the classical view of fine sediment transport and deposition in streams, particles are expected to be removed from flowing water simply by direct sedimentation onto the streambed. However, recent research has demonstrated that fine sediments can propagate into pore spaces in the streambed due to hyporheic exchange and be removed by a combination of physical and chemical processes. This behaviour can significantly alter fine sediment size distributions during in-stream sediment transport because the physical transport of fine particles and their attachment to bed sediment grains are both a function of the particle size. Herein, we present model simulations for deposition of suspended sediments with a bimodal size distribution. We also applied this approach to analyse the results of laboratory flume observations of suspended sediment deposition. Results from model simulations and flume experiments clearly show that the rate of particle deposition increases with increasing particle size. Thus, the larger particles are preferentially removed from mixtures and there is a fining of the mixed suspensions over time. Both particle deposition mechanisms, i.e. particle sedimentation and filtration, contribute to the fining of the mixed fine particle suspensions over time, and their effects are clearly demonstrated using the fundamental process-based model. These results clearly demonstrate the effects of stream-subsurface exchange on the temporal evolution of the suspended fine sediment size distribution in downstream transport.     

河西走廊中西部干旱区极端暴雨个例分析

利用常规、自动气象观测站资料、卫星资料及NCEP 1°×1°再分析资料,对2012年6月4 5日河西走廊中西部干旱区极端暴雨天气过程的影响系统配置、中尺度特征、水汽输送、不稳定能量等方面进行了诊断分析。结果表明:此次暴雨发生在地面冷锋过境后,降温冷凝作用明显,对流层高层存在强抽吸作用,中层高原低涡受其下游弱脊阻挡较长时间维持在暴雨区上空,低层存在切变线,高低空系统的耦合提供了中尺度对流系统发生、发展的有利条件;水汽主要来自对流层中低层东、西两路及高层南路三支水汽输送通道,西路水汽输送强度最大,东路水汽输送受小高压影响显著,暴雨开始后6 h才完整建立,暴雨中心整层大气可降水量达到了该地区夏季平均值的两倍多;通过降温、增湿作用近地面出现对流不稳定能量,自由对流高度较低;涡旋云系的冷空气侵入处,不断激发出6个β中尺度的对流单体,暴雨中心玉门两次受其中4个单体的影响,产生短时强降水。     

基于ArcGIS的1:80万吉林省地震构造图绘制技术

利用ArcGIS平台完成1:80万吉林省地震构造图绘制工作,由此表述专业图件的一般绘制过程与主要技术手段.对其项目的一般绘制过程,包括组织实施方式、原始资料规范化、图件的专业分层做简要说明.对绘制过程中的技术难点、技术手段,如:地理信息数据库的建立、数据导人、图像矢量化、空间归并、符号化等关键技术,做深人探讨.文中介绍...     

第二次世界大战后英国乡村景观研究的脉络走向及启示

英国是全球乡村景观建设和发展的典范。从地理学、生态学及规划学等综合的视角出发,首先从社会背景上分析二战后英国乡村景观的演变轨迹;其次从学术背景梳理英国乡村景观的研究历程,并从学科角度提炼不同阶段的研究重点及研究特征;最后从研究趋势方面讨论学者们最新的研究议题。在梳理和总结英国乡村景观研究的基础上,提出对中国乡村景观研究的启示和借鉴。