小良试验站三种植被类型地表径流效应的对比研究   总被引：13，自引：0，他引：13  

周国逸  余作岳 《热带地理》1995,15(4):306-312

本文分析研究了３种植被类型下的地表径流在汇流、洪峰及径流过程上的特征，差异是巨大的。在径流过程上桉树林和裸地的变地剧烈，几乎没有什么调蓄作用，洪峰流量占一次性降水径流量的绝大部分，涨水和退水流量都较小。本文应用灰色系统ＧＭ（２，１）模型，成功地预测了以年和以月为时间尺度的地表径流序列，其预测模型可以用来对这些时间尺度的地表径流进行预报。  相似文献   

兴1井水位的映震特征     

张文阁  迟恭财等 《地震》1995,(2):157-160

兴1井是辽宁省内最早建成的静水位观测井，已有近20年的观测历史。系统分析预测以来的资料，发现该井水位有很强的映震能力并有一定的映震规律，可进行单井水位异常预报地震震级与发震时间的科学试验。  相似文献   

Interrelation between fault zone structures and earthquake processes     

Keiiti Aki 《Pure and Applied Geophysics》1995,145(3-4):647-676

In order to develop capabilities for predicting earthquake processes on the basis of known fault zone structures and stress conditions, we need to find relations between seismogenic structures and processes. In the present paper we search for the scale dependence in various earthquake phenomena with the hope to find some structures in the earth that may control the earthquake processes. Among these phenomena, we shall focus on (1) geologic structures which play some role in nucleation and stopping of earthquake fault rupture, (2) depth ranges of the brittle seismogenic zone, (3) asperities and barriers distributed over a fault plane, (4) source-controlledf _max effect, (5) nonfractal behavior of creep events, and (6) temporal correlation between codaQ ^–1 and seismicity of earthquakes with magnitude characteristic to a given area. Our review of various scale-dependent phenomena leads us to propose a working hypothesis that the temporal change in codaQ ^–1 may reflect the activity of creep fractures near the brittle-ductile transition zone.  相似文献   

Multispectral remote sensing of biomass burning in West Africa     

J. Ricardo  A. De França  J. -M. Brustet  J. Fontan 《Journal of Atmospheric Chemistry》1995,22(1-2):81-110

Remote sensing measurements provide a vauable means of determining the extent of burning areas and of estimating the overall distribution of pollutant sources (identified from experimental studies) in time and space. This distribution has to be taken into account in the boundary conditions of chemistry atmospheric models.Recent methods developed for the remote sensing of active fires in tropical or temperated forest zones, have been found to be completely inadequate for fire detection on West African savannas. In order to accurately estimate the active fire distribution in the function of different sorts of West African savannas (Sahelian, Sudanian and Guinean) and forests, a multispectral methodology has been developed based on NOAA/11-AVHRR satellite data, with the purpose of eliminating as much as possible the problems related to large surface heterogeneity, confusion and bias, produced by clouds, smoke, haze, background emissivities, etc.Unlike other methods, the results show that the multispectral method, in spite of its selectivity, provides realistic results, and does not under- or over-estimate the number of fires that can be sensed by the satellite. Consequently, this methodology is more appropriate than the simplest ones for a systematic sensing of this phenomenon.  相似文献   

GBPP－100型地面雨滴谱仪测量的可靠性   总被引：6，自引：0，他引：6  

陈金荣  马生伟 《南京气象学院学报》1995,(2)

用ＧＢＰＰ－１００型地面雨滴谱仪与吸水纸斑，点法进行同步观测，对比分析ＧＢＰＰ－１００型地面雨滴谱仪测量的可靠性。结果表明：（１）两种方法测量雨滴谱所得资料除平均直径、均立方根直径相似性稍差外，其它特征量的线性相关显著性水平均为０．００５；（２）两种方法所得雨滴谱资料除平均直径、均立方根直径、降水强度稍有差异外，其它特征量均无显著差异。  相似文献   

Applications of satellite data in the study of monsoon variability     

R. R. Kelkar 《Journal of Earth System Science》1993,102(1):271-281

This paper discusses the use of satellite data for studying climate change, with particular emphasis on the inter-annual variability of the Indian southwest monsoon. Precipitation estimates made from INSAT-1B radiance data are shown to bring out the variations that occurred in the monsoon rainfall of 1987 and 1988. Outgoing Longwave Radiation derived from INSAT-1B shows good correspondence with precipitation patterns.  相似文献   

Areal extent of the 1988 flood in Bangladesh: How much did the satellite imagery show?     

Harun Rasid  M. A. H. Pramanik 《Natural Hazards》1993,8(2):189-200

This paper presents the methods and results of visual interpretation of satellite imagery for estimating areal extent of the 1988 flood in Bangladesh. The main limitation of this method was that cloud-free images were not available for the peak flood period in the first week of September. Relatively cloud-free images on three selected dates in the last three weeks of September showed that areas of inundation on those dates ranged from 44000 to 60000 km² ± 5% (31 to 42% of Bangladesh). The Government of Bangladesh official estimates of the areal extent of flooding were tentative in nature, since these were based on a choropleth map of relative proportions (percentages) of flooding in different parts of the country. The official estimate of the maximum extent of flooding was 82000 km² (57% of Bangladesh), i.e. 15 to 26% larger than the area shown on satellite imagery. The actual extent of flooding was certainly larger than the estimates from satellite imagery but, perhaps, smaller than the official estimates, since a reduction of 15 to 26% of flood area in one to three weeks seemed unlikely. An alternative method of mapping flood-affected areas by using newspaper-interpreted data was attempted, but the method had limited values because of reporting bias.  相似文献   

卫星测高研究应用新进展   总被引：3，自引：1，他引：3  

王广运  王海瑛 《地球科学进展》1993,8(6):36-43

卫星测高是利用空间技术进行海洋观测的崭新技术手段。GEOSAT卫星的升空又使得这一研究向前大大地推进。本文简要介绍卫星测高在确定大地水准面精度、研究岩石圈特性、探测海底深部构造、研究海洋动力环境以及其经济效益和社会效益的最新进展。  相似文献   

Landsat　TM及JERS－1　SAR数据在金矿探测中的应用研究     

张满郎  郑兰芬 《遥感学报》1996,(4)

金矿遥感探测之关键在于成矿构造及铁氧化物、含羟基蚀变矿物的信息提取。ＪＥＲＳ—１ＳＡＲ在构造探测方面具有很大的优势，可通过噪斑消除及边缘增强的空间滤波来提取构造信息。ＬａｎｄｓａｔＴＭ可通过主成分变换，比值分析－主成分变换来提取蚀变矿物波谱信息、抑制植被波谱干扰。这两种遥感数据的复合处理可综合蚀变与构造信息。  相似文献   

亚洲MAGSAT卫星磁异常图   总被引：9，自引：3，他引：9       下载免费PDF全文

安振昌  谭东海  王月华  徐元芳 《地球物理学报》1996,39(4):461-469

使用２０多万个ＭＡＧＳＡＴ卫星磁测数据，编绘亚洲卫星标量（△Ｆ）和矢量（△Ｘ，△ｙ，△Ｚ）磁异常图（２０°ｓ－６０°Ｎ，５０°Ｅ－１６０°Ｅ）．为了提取岩石层卫星磁异常，首先对ＭＡＧＳＡＴ卫星数据进行了筛选，然后进行主磁场、磁层场、电离层场和感应场改正，并消除虚假测点．将卫星数据分成黎明组、黄昏组和联合组，分别绘制相应的卫星磁异常图．根据１°×１°的网点值，用计算机编绘亚洲卫星磁异常图．初步分析了卫星磁异常与大地构造的关系．  相似文献