1993年9月份首都圈地区M＿L≥2．0级地震

１９９３年９月份首都圈地区Ｍ＿Ｌ≥２．０级地震１９９３年９月份在首都圈（３８．０°—４１．０°Ｎ，１１３．０°—１２０．０°Ｅ）范围内，共发生１７次Ｍ＿Ｌ≥２．０地震，其中１２次２—２．９级地震，５次Ｍ＿Ｌ＞３的地震。震级最大的一次为９月２７日发生在...     

1996年5月首都圈地区M_L≥2．0地震动态

１９９６年５月首都圈地区Ｍ_Ｌ≥２．０地震动态根据国家地震局地球物理研究所四室提供的资料，本月在首都圈（３８．０°～４１．０°Ｎ，１１３．０°～１２０．０°Ｅ）范围内，共发生ＭＬ≥２．０地震１４次，其中震级最大的为５月４日河北大城ＭＬ３．９地震。唐山?..     

1994年9月首都圈M＿L≥2．0地震动态

１９９４年９月首都圈Ｍ＿Ｌ≥２．０地震动态１９９４年９月份在首都圈（３８．０°─４１．０°Ｎ，１１３．０°─１２０．０°Ｅ）范围内，共发生Ｍ＿Ｌ≥２．０以上地震１１次，其中最为显著的是９月９日发生在河北卢龙Ｍ＿Ｌ≥３．２地震（见下表）。本月发生的２级...     

1994年5月份首都圈地区M_L≥2.0地震

本月在首都圈（38．0°－41．0°N，113．0°—120．0°E）范围内，共发生ML≥2．0地震20次，其中2至2．9的18次，震级最大为5月24日河北安平ML3．5地震（见下表人本月地震活动频度较上月有所增强，首都圈东西两区2级以上地震活动呈北东东向分布，北京及其邻近地区无2级以上地震发生。1994年5月份首都圈地区M_L≥2.0地震@王琳瑛$国家地震局地球物理研究所@舒曦$国家地震局地球物理研究所     

1996年9月首都圈地区M_L≥2．0地震动态

１９９６年９月首都圈地区Ｍ_Ｌ≥２．０地震动态根据国家地震局分析预报中心提供的资料，１９９６年９月份在首都圈（３８．０°～４１．０°Ｎ，１１３．０°～１２０．０°Ｅ）范围内，共发生ＭＬ≥２．０地震１２次，其中震级最大的为９月２４日河北卢龙ＭＬ３．１地?..     

1999年5月份首都圈地区ML≥2.0地震动态

根据中国地震局地球物理研究所四室提供的资料,１９９９年５月首都圈地区（３８０°～４１０°Ｎ,１１３０°～１２００°Ｅ）共发生ＭＬ≥２０地震３３次,其中ＭＬ≥３０地震５次,（见表１）。５月１５日１１时应县发生一震群,５月１５日１６时１１分和１８时３４分应县ＭＬ４６地震是本月最显著的事件。本月地震频度与上月相比,明显升高（包括应县地震１９次）,首都圈西部地震较为活跃,中部相对较为平静,东部保持原有的活动水平。表１　１９９９年５月份首都圈地区ＭＬ≥２０地震序号发　震　时　刻　　年月日时…     

1996年6月首都圈地区M_L≥2．0地震动态

１９９６年６月首都圈地区Ｍ＿Ｌ≥２．０地震动态根据国家地震局地球物理研究所北京遥测地震台网（ＢＳＴＮ）提供的资料，本月在首都圈（３８．０°～４１．０°Ｎ，１１３．０°～１２０．０°Ｅ）范围内，共发生ＭＬ≥２．０地震１５次（见附表），其中最显著的事件是...     

中国西南和印缅地区8级地震活动特征及趋势

本分析了１９００年以来北纬１５°－３２°,东红８５°－１０５°,中国西南及印缅地区７级以上地震的时空特征,得出Ｍ≥７．５级地震有密集－平静现中活跃期持续时间长、短交替、印缅地区７级地震启动是８级地震的重要标志,８级地震发生在７级地震密集区附近。     

地震活动的月相效应

本文利用中国大陆１９１０年以来６．０级以上和首都圈地区１９６６以来１．０级以上大量地震资料，对地震活动的月相效应进行了研究。结果表明，发生在各个月相上的地震频次明显受月相的调制和制约，并且有一定的规律性，月相效应的最大幅度可影响地震活动平均频次的２５％以上，证明了地震活动的月相效应明显存在，其影响不可忽略。结果还表明，月相效应的基本特征是具有半月和全月周期性，此外，对首都圈地区地震活动以及唐山，邢     

台湾海峡发生7．3级地震

台湾海峡发生７．３级地震１９９４年９月１６日，台湾海峡发生７．３级地震。据我国地震台网测定，这次地震发生于１４时２０分，震中位置：２３．°Ｎ，１１８．５°Ｅ。至１１月１０日１５时０７分止，共发生３．０级以上余震２１４次，其中３．０～３．９级１７３次；...     

A Monte Carlo study of rainfall forecasting with a stochastic model

A procedure for short-term rainfall forecasting in real-time is developed and a study of the role of sampling on forecast ability is conducted. Ground level rainfall fields are forecasted using a stochastic space-time rainfall model in state-space form. Updating of the rainfall field in real-time is accomplished using a distributed parameter Kalman filter to optimally combine measurement information and forecast model estimates. The influence of sampling density on forecast accuracy is evaluated using a series of a simulated rainfall events generated with the same stochastic rainfall model. Sampling was conducted at five different network spatial densities. The results quantify the influence of sampling network density on real-time rainfall field forecasting. Statistical analyses of the rainfall field residuals illustrate improvement in one hour lead time forecasts at higher measurement densities.     

Earthquake Engineering and Engineering Vibration Aims And Scope

正This journal is established by the Institute of Engineering Mechanics(IEM),China Earthquake Administration,to promote scientific exchange between Chinese and foreign scientists and engineers so as to improve the theory and practice of earthquake hazards mitigation,preparedness,and recovery.To accomplish this purpose,the journal aims to attract a balanced number of papers between Chinese and     

Foreword

Destructive earthquakes have caused great damage in China and the United States and collapsing buildings havecaused many deaths and injuries. The field of earthquake engineering studies earthquake hazards, the occurrence ofearthquakes of various magnitudes, the nature of the ground shaking during an earthquake, the vibration of structuresduring earthquakes, the strengthening of existing structures and the design of new structures to be earthquake resistant,and finally, how to cope with earthquake damage and restore a city to normal functioning. Such efforts are in progressin both countries, but unfortunately, the language barrier interferes with the free flow of information between China andthe Untied States. It would be mutually beneficial if some means could be developed to promote the exchangeof information across the Pacific Ocean. This new journal has been established for this purpose and its success willbe an important step in promoting earthquake engineering in China and the United States.     

WORLD ASSOCIATION FOR SEDIMENTATION AND EROSION RESEARCH(WASER)

正President:Giampaolo Di Silvio,Italy Vice Presidents:Ulrich C.E.Zanke,Germany Zhao-yin Wang,China The World Association for Sedimentation and Erosion Research(WASER),inaugurated on Oct.19,2004,is an independent non-governmental,non-profit organization.The mission of WASER is to promote international co-operation on the study     

Enhancing remote sensing research on global change to improve our understanding on Earth system processes

正Global Change includes climate change and other environmental changes caused by the joint interaction among various layers of Earth. From the positive side, global change provides new opportunities to human and other living forms on Earth. In the meantime, it creates tremendous challenges and negative impact. At present, the negative impacts have reached all primary processes of the global ecosystem and every aspect of human society, especially causing degradation of the ecosystem. For instance, intensive deforestation causes decline of biodiversity; global warming causes sea level rise and increases     

Dissolved Carbohydrate Concentration,Composition, and Bioavailability to Microbial Heterotrophs in Stream Water

Dissolved total carbohydrates (DTCH), dissolved free monosaccharides (DFMS), dissolved organic carbon (DOC), biodegradable DOC (BDOC), and humic substances (HS) were measured in White Clay Creek (WCC), a stream in southeastern Pennsylvania Piedmont, USA. Samples were collected over different seasons and under baseflow and stormflow conditions. DOC concentrations ranged from 1.0 to 12.8 mg/L C with the highest concentrations associated with stormflows. Carbohydrates ranged from 0.42 to 12.4 μM and accounted for 2.9 to 12.7% of the DOC. Humic substances represented the major DOC fraction, accounting for 55 to 72% of the DOC pool under all flow conditions. The humic fraction had a lower carbohydrate content (4.4%) than the non-humic fraction of DOC (7.2%). Stormflow DOC was enriched in carbohydrates relative to baseflow DOC, but the percentage of humic-C changed little. Carbohydrates were primarily present as dissolved polysaccharides (55%), but a significant fraction was bound to humic substances (40%), while a small proportion was present as monosaccharides (5%). The major monosaccharides in stream water, listed in order of decreasing concentration, included glucose, galactose, rhamnose, xylose, arabinose, mannose, and fucose. On average (30.6 ± 7.4)% (n = 44) of the stream water DOC was biodegradable, and carbohydrates accounted for 9.9 to 17.7% of the BDOC.