现代黄河三角洲土地利用变化分析

人类对海岸带的开发利用影响着海岸的变迁。土地利用和土地覆被变化可以说是自然与人文过程交叉最为密切的问题，是人地关系的具体体现。通过对黄河三角洲土地利用变化的研究，可了解人为因素对三角洲海岸带的开发利用状况及其对海岸侵蚀的影响。根据1987年和2001年两期卫星遥感图像和2001年野外调查数据，运用地理信息系统方法及数理统计方法，分析了现代黄河三角洲地区1987年至2001年土地利用／覆被的数量变化和空间变化特征；揭示了该地区各类土地利用数量变化的幅度、速度和土地利用空间变化的主要类型；阐明了该区各类土地利用变化的区域特点。该地区土地利用变化速度比整个环渤海地区速度快，草地、滩地和不明地类这3种类型大量减少，其他类型增多。从变化率来看，养殖区、库塘、油田用地增长最快。库塘、海滩养殖区等类型的增加，滨海草地的减少，使海岸侵蚀加剧。     

莺歌海盆地形成与演化的动力学机制

莺歌海盆地位于印支半岛与南海北部大陆边缘交接区,复杂的地质构造背景使其形成演化的动力学机制成为国内外的研究焦点。从区域动力学演化的角度,系统分析了影响莺歌海盆地发育的印支地块构造演化特征,认为莺歌海盆地构造演化主要受印支半岛早期的逃逸挤出构造和晚期的挤压-伸展构造系统影响(或控制),在此动力学驱动机制下,莺歌海盆地新生代以来的构造演化经历了3个阶段,即左旋走滑-伸展裂陷阶段、中下地壳韧性伸展-热沉降阶段和加速沉降阶段。     

海上浮动软管的三维静态分析

提出了海上浮动软管的三维静态分析模型。在四级海情下，对输送柴油的软管求得了解析解，得出了软管在侧向和垂直方向的偏移及其所受的拉力，认为此时的软管是不安全的。     

Modelling of flow around a near-bed pipeline with a spoiler

Flow around a pipeline with and without a spoiler near a smooth wall is simulated by solving the Navier–Stokes equations. Finite-difference formulation with a second-order upwind scheme in a curvilinear coordinate system is employed. The influences of the spoiler on hydrodynamic forces, pressure distribution, vortex shedding frequency, velocity profile under the pipe, as well as shear stress on the wall are investigated. The attachment of a spoiler significantly increases drag, root-mean-square (RMS) lift, flow through the gap between the pipe and the wall and shear stress on the seabed around the pipe. The spoiler also generates a non-zero mean downward force on the pipeline, which may enhance the self-burial of the pipeline.     

Bathymetry of the Tonga Trench and Forearc: a map series

Four new bathymetric maps of the Tonga Trench and forearc between 14 °S and 27 °S display the important morphologic and structural features of this dynamic convergent margin. The maps document a number of important geologic features of the margin. Major normal faults and fault lineaments on the Tonga platform can be traced along and across the upper trench slope. Numerous submarine canyons incised in the landward slope of the trench mark the pathways of sediment transport from the platform to mid- and lower-slope basins. Discontinuities in the trench axis and changes in the morphology of the landward slope can be clearly documented and may be associated with the passage and subduction of the Louisville Ridge and other structures on the subducting Pacific Plate. Changes in the morphology of the forearc as convergence changes from normal in the south to highly-oblique in the north are clearly documented. The bathymetric compilations, gridded at 500- and 200-m resolutions and extending along 500 km of the landward trench slope and axis, provide complete coverage of the outer forearc from the latitude of the Louisville Ridge-Tonga Trench collision to the northern terminus of the Tonga Ridge. These maps should serve as a valuable reference for other sea-going programs in the region, particularly the Ocean Drilling Program (ODP) and the National Science Foundation MARGINS initiative.     

Atmospheric forcing of the eastern tropical Pacific: A review

The increase in marine, land surface, atmospheric and satellite data during recent decades has led to an improved understanding of the air–sea interaction processes in the eastern tropical Pacific. This is also thanks to extensive diagnoses from conceptual and coupled ocean–atmosphere numerical models. In this paper, mean fields of atmospheric variables, such as incoming solar radiation, sea level pressure, winds, wind stress curl, precipitation, evaporation, and surface energy fluxes, are derived from global atmospheric data sets in order to examine the dominant features of the low level atmospheric circulations of the region. The seasonal march of the atmospheric circulations is presented to depict the role of radiative forcing on atmospheric perturbations, especially those dominating the atmosphere at low levels.In the tropics, the trade winds constitute an important north–south energy and moisture exchange mechanism (as part of the low level branch of the Hadley circulation), that determines to a large extent the precipitation distribution in the region, i.e., that associated with the Inter-Tropical Convergence Zone (ITCZ). Monsoonal circulations also play an important role in determining the warm season precipitation distribution over the eastern tropical Pacific through a large variety of air–sea–land interaction mechanisms. Westward traveling waves, tropical cyclones, low latitude cold air intrusions, and other synoptic and mesoscale perturbations associated with the ITCZ are also important elements that modulate the annual rainfall cycle. The low-level jets of the Gulf of California, the Intra-Americas Sea (Gulf of Mexico and Caribbean Sea) and Chocó, Colombia are prominent features of the eastern tropical Pacific low-level circulations related to sub-regional and regional scale precipitation patterns. Observations show that the Intra-Americas Low-Level Jet intensity varies with El Niño/Southern Oscillation (ENSO) phases, however its origin and role in the westward propagation and development of disturbances that may hit the eastern tropical Pacific, such as easterly waves and tropical cyclones, are still unclear. Changes in the intensity of the trade winds in the Caribbean Sea and the Gulf of Mexico (associated with eastern tropical Pacific wind jets) exert an important control on precipitation by means of wind–topography interactions. Gaps in the mountains of southern Mexico and Central America allow strong wind jets to pass over the continent imprinting a unique signal in sea surface temperatures and ocean dynamics of the eastern tropical Pacific.The warm pools of the Americas constitute an important source of moisture for the North American Monsoon System. The northeastern tropical Pacific is a region of intense cyclogenetic activity, just west of the coast of Mesoamerica. Over the oceanic regions, large-scale properties of key variables such as precipitation, moisture, surface energy fluxes and wind stress curl are still uncertain, which inhibits a more comprehensive view of the region and stresses the importance of regional field experiments. Progress has been substantial in the understanding of the ocean and atmospheric dynamics of the eastern tropical Pacific, however, recent observational evidence such as that of a shallow meridional circulation cell in that region, in contrast to the classic concept of the Hadley-type deep meridional circulation, suggests that more in situ observations to validate theories are still necessary.This paper is part of a comprehensive review of the oceanography of the eastern tropical Pacific Ocean.     

天然感潮河道水流紊动特性分析

采用多谱勒三相流速仪，在长江口徐六泾水文观测断面分别进行了涨潮、落潮时中泓与近岸垂线的流速观测，根据这些观测资料，对天然感潮河段潮流紊动的周期、频率、概率密度函数等进行了定量的数学描述，并对时均流速、紊动强度、雷诺应力等沿垂线分布进行了分析计算。     

Stress Sharing Behavior and Its Mechanism during Consolidation Process in Composite Ground Improved by Sand Compaction Piles with Low Replacement Area Ratio

In order to accurately design a sand compaction pile (SCP) with low replacement area ratio, it is important to understand the mechanical interaction between the sand pile and clay ground and its mechanism during consolidation process in composite ground. In this article, therefore, a series of numerical analyses on composite ground improved by SCP with low replacement area ratio were carried out. The applicability of numerical analyses, in which an elasto-viscoplastic consolidation finite element method was applied, were confirmed by comparing the results obtained from a series of laboratory model tests with the composite ground improved by SCP. Through the results of the numerical analyses, mechanical behavior of the sand pile and clay in composite ground during consolidation is elucidated, together with a stress sharing mechanism between sand pile and clay.     

基于荧光原理的叶绿素a传感器校准方法研究

利用传感器对水体叶绿素a 浓度进行原位测量是获取实时、连续、长时间序列数据的重要手段。本文在对RBR 传感器和ECO（Environmental Characterization Optics）传感器进行原理分析和线性度、稳定性、重复性等基本性能测试的基础上，利用单一藻种培养液和2020年南海北部海域现场数据校准传感器，并对新的传感器校准系数进行验证。结果表明：两台传感器使用新系数比原出厂系数的叶绿素a 浓度测量准确度有明显提高。RBR 传感器现场数据校准系数的计算结果与叶绿素a 标准值误差最小，平均绝对误差从1.93 μg/L 减小到0.35 μg/L，平均相对误差从55.1%减小到10.9%；ECO 传感器藻液系数明显优于出厂系数和现场数据校准系数的计算结果，平均绝对误差从1.76 μg/L 减小到0.59 μg/L，平均相对误差从50.3%减小到15.1%。传感器测量准确度的提高，可为海洋环境监测、海洋生态灾害预警等工作获取真实可靠数据提供支撑。     

埕岛油田海区海底地形变化及预防措施

综合在胜利石油管理局埕岛油田海区多年来工程测绘与地质勘察资料 ,对埕岛油田海区地形地貌特征及其变化与发育趋势进行了论述 ,同时讨论了埕岛油田海上工程中需要重视的问题以及有关的工程防护问题。