华北地区地震短期综合预测方法研究

在对华北地区114项骨干前兆观测资料进行地震短期异常前兆信息量提取与计算基础上，结合华北地区地质构造、地震活动、地壳厚度，特别是现今动力学环境因子等因素，研究了华北地区地震短期异常前兆信息量的时、空演化特征及其与地震的关系，给出了华北地区Ms≥5地震短期综合预测的指标和方法。经R值评分检验表明，该方法具有一定的地震预测效果。     

RATIONAL BASIS FOR SUSPENDED SEDIMENT MODELING

This paper presents a rational basis to model the transport of suspended sediment. The loose-boundary condition for 3D models and the adjustment coefficients for both the depth-integrated 2D and laterally integrated 1D models are treated comprehensively. A combination of Dirichlet and Neumann conditions is proposed as the loose-boundary condition. The adjustment coefficient for 2D models is obtained on the basis of the proposed boundary condition and analytical solutions developed for some simple cases of non-equilibrium transport of sediment in uniform flows. The adjustment coefficient for 1D models for natural rivers is further obtained from lateral integration. Comparisons with analytical solutions and a considerable amount of laboratory and prototype data show that mathematical models developed along the proposed line of attack would well simulate the transport of suspended sediment in practical problems.     

河网水流数值模拟方法研究

讨论了河网概化的一般原则,并在分析单一河段水流数学模型的基础上,建立了可以适用于一般河网体系水流数值计算的数学模型,并采用荆江—洞庭湖的相关资料进行了验证.结果表明,模型的计算值与实测值吻合较好,说明该模型具有较好的适用性.     

三极断面测深技术在第四系水源地勘探中的应用

介绍了三极断面测深技术在第四系水源地勘探中的应用。钻探验证结果表明，该方法能够准确地圈定第四系地层中的含水体，可为供水水源地选择提供必要的地质资料。     

人文地理学研究方法述要

人文地理学是地理学的重要分支学科，20世纪60年代在人文地理学领域内进行的计量革命引发了人们对地理学的理论建设以及地理学方法论 思考，但是计量革命从一开始就经历着种种责难，文章从对计量革命这一运动的观察开始，对人文地理学方法论进行了反思，在此基础上对当前人文地理学采用的方法进行概括总结，并对一些研究方法应用前景予以展望。     

Interannual and Interdecadal Variability of Winter Precipitation over China in Relation to Global Sea Level Pressure Anomalies

Based on the method of rotated principal component (RPC) analysis and wavelet transforms, the win-ter precipitation from 36 stations over China for the period 1881-1993 is examined. The results show thatthe three leading space-time modes correspond, in sequence, to winter rainfall anomalies over the reaches ofthe Yangtze River, the bend of the Yellow River, and the northeastern region of China. The three modes ex-hibit interannual oscillations with quasi-biennial and 8-year periods as well as interdecadal oscillationswith 16- and 32-year periods. The interannual oscillation (＜ 10 years) occurs in phase over the differentareas, and its maximum amplitude migrates northward considerably with prominent interdecadal variations.However, the interdecadal oscillations (10-32 years) are out of phase over the different regions, and theamplitude variations have the characteristics of stationary waves.The rainfall anomalies appear to be closely re lated to the anti-phase changes of mean sea-level pres-sure (SLP) over the Asian mainland and the North Pacific. When the SLP rises over the North Pacific anddecreases over the Asian mainland, the precipitation over East China increases noticeably. The linkage be-tween the rainfall over China and the SLP anomalies apparently results from the strength of the East Asianwinter monsoon and its associated temperature and moisture advection.     

耕地供需预测方法研究——以博白县为例

耕地是土地的精华，我国新一轮的土地利用总体规划突出了耕地保护和可持续发展，而作为土地利用总体规划调整指标中最重要的耕地指标如何确定。首要的前提是作好预测工作，文章结合博白县土地利用总体规划的实践，遵循供给帛约和引导需求的原则，探讨采用定性和定量相结合的手段进行耕地供需预测的方法。预测的结果不仅保证了耕地总量的动态平衡，同时保证了重点建设项目用地的需要，该研究可为土地利用总体规划的编帛工作提供科学依据。     

陕北洛川塬黄土崩滑及谷坡扩展模式

陕北洛川黄土塬是水土流失严重的地区。通过野外调查发现黄土崩滑作用是造成该区水土流失的主要之一，发育于黄土塬-沟谷过渡地带。该区黄土崩滑首次被划分为单面崩滑及栅格崩滑两种基本类型。黄土单面崩滑主要分布于冲沟、切沟地貌环境，而栅格崩滑主要分布于级别较高的沟道之中，活跃于区域Ⅲ、Ⅳ级沟道，显示出黄土崩滑与区域水文网之间的对应关系。根据地貌景观和沟谷几何特征第一次提出洛川黄土塬河道谷坡以陡倾加宽和鱼鳞状后退扩展为模式。黄土崩滑是蚕塬的重要方式，在水土保持过程中，就加强不同类型崩滑的针对性研究、预报和防护治理，促进水保效益的提高。     

基于观测值质量指标的GPS观测量随机模型分析

卫星高度角、载噪比及信号强度是反映GPS观测值质量的重要指标,基于这些指标的随机模型可进一步削弱GPS残余大气延迟、衍射以及多路径效应等误差的影响,但这些随机模型对不同误差的处理效果具有一定差异.为合理利用这些随机模型,利用实际观测数据进行了比较计算,结果表明信号强度和载噪比随机模型的效果基本一致,当观测数据中载噪比输出时,可用信号强度代替载噪比建立随机模型;信号强度和载噪比随机模型对削弱衍射误差十分有效,而高度角随机模型能更有效地削弱残余对流层延迟误差.