洪山泉流量动态系统分析

为查明洪山泉域的开采程度,在前人研究基础上,建立了现阶段泉流量-降雨量的线性模拟模型。通过对模型的系统辨识,对系统的"慢时变"现象作出了合理解释,并发现系统在1994年以后发生了"快时变",说明开采量从1995年开始迅猛增加。同时,由多年来泉流量序列的自相关分析,发现其宏观周期到2000年基本保持不变,说明虽然第二输入(即人为开采量)对该系统的作用已不可忽略,但尚未达到足以改变其宏观频率的程度。     

Neodymium isotopic variations in Northwest Pacific waters

Four vertical profiles of the concentration and isotopic composition of Nd in seawater were obtained in the western North Pacific. Two profiles from the Kuroshio Current regime showed congruently that although the Nd concentration increases gradually with depth, its isotopic composition varies significantly with depth depending upon the water mass occupying the water column. The high-salinity Kuroshio waters originating from the North Pacific Tropical Water (NPTW) carry the least radiogenic Nd (?_Nd = −7.4 to −8.7) to this region at ∼250 m from the western margin continental shelves, most likely from the East China Sea. The Nd isotopic compositions in the North Pacific Intermediate Water (NPIW) that occurs at 600 to 1000 m in the subtropical region are fairly uniform at ?_Nd = −3.7. The profile data from the ∼38° to 40°N Kuroshio/Oyashio mixed water region off Sanriku of Honshu, Japan, also suggest that the newest NPIW with ?_Nd = −3.2 is formed there by the mixing of various source waters, and the radiogenic component of Nd is derived mainly from the Oyashio waters.In the Pacific Deep Water (PDW) below ∼1000 m, the Nd isotopic composition is neither vertically nor horizontally homogeneous, suggesting that it serves as a useful tracer for sluggish deep water circulation as well. Two profiles from the Izu-Ogasawara Trench showed a minimum ?_Nd value at ∼2000 m, suggesting that there exists a horizontal advective flow in the vicinity of Honshu, Japan. There is some evidence from other chemical properties to support this observation. The waters below 4000 m including those within the trench in the subtropical region have ?_Nd values of around −5, suggesting that the deep waters are fed from the south along the western boundary, ultimately from the Antarctic Bottom Water (AABW) in the South Pacific. This extends up to ∼40°N along the Japanese Islands. In the subarctic region (>∼42°N), the waters have more radiogenic Nd with ?_Nd > −4.0 throughout the water column, presumably due to the supply of Nd by weathering in such igneous provinces as the Kuril-Kamchatska-Aleutian Island chain. The lateral inhomogeneity of the Nd isotopic composition in PDW suggests that there may be different circulation and mixing regimes in the North Pacific Basin.     

国内旅游文化开发研究综述

旅游文化是一种重要的旅游资源。是旅游地可持续发展的源泉。在旅游地开发过程中，文化事项如何转化为旅游产品，即旅游文化开发是一个极具实际应用价值的研究课题。目前，国内对于旅游文化开发的研究还没有能够形成一个完整的理论研究体系，并且缺少成熟的研究方法，具体到实践中可操作性还比较弱。在查阅了国内近20年中的众多相关研究文献的基础上，试图从应用理论、开发实践、方法探索3个方面对国内的旅游文化开发研究做一个系统的总结。     

科尔沁沙地土地沙漠化的历史与现状

科尔沁沙地是我国自然条件相对较好的一个沙地，有着广阔的治理前景。回顾科尔沁沙地的历史变化，认为科尔沁沙地是一个全球气候变化大趋势下由人类生产活动过度而形成的沙漠化区域，在金代至清代之间由于人为活动强度减弱，曾经发生明显的沙漠化逆转。根据全国沙漠化普查所获得的资料，研究分析了科尔沁沙地土地沙漠化现状及其特点，结合土地沙漠化发生的历史过程，讨论了这一地区沙漠化的治理策略。     

博斯腾湖向塔里木河输水风险分析方法

为了拯救塔里木河下游生态环境，塔里木河流域管理局根据博斯腾湖从1999年到2003年处于丰水期，湖泊处于高水位的有利时机，从2000年5月到2003年6月实施5次向塔里木河下游生态应急输水，结束塔里木河下游300多km河道近30年的断流历史。现在的问题是“博斯腾湖向塔里木河生态输水能否持续?”，“保证可持续输水的风险有多大?”本文以解决此问题为实例，介绍一般水库调节计算和水库特征水位确定方法；主要探讨水库(湖泊)向下游输水可持续性风险分析问题，提出的方法称为“水库输水可持续性风险计算时历试算法”，简称为“试算法”(T＆E方法)；并将此方法应用于实例中，计算博斯腾湖向塔里木河下游输水的可持续风险。     

海量地形数据的Web发布与交互浏览

阐述了基于CORBA的分布式平台实现异构网络环境下海量地形数据的Web发布与服务的关键技术 ,通过一个实验系统对上述方法进行了测试     

不同降水天气系统自然降水特征及火箭人工增雨潜力分析

统计分析了1981~2000年20年中15种降水天气系统影响下河北地区自然降水特征,并对火箭人工增雨的潜力进行了初步分析。统计分析表明:西来槽类、高空低涡类、冷锋、切变线和副高后部等天气系统是影响河北地区的主要降水系统,其降雨量和降雨日数占到了90%以上;不同的天气系统在不同季节对降水的贡献有所不同,其中西来槽类的降雨量和降雨日数均居首位,开展人工增雨催化作业机会最多;夏季降水系统最强,云水资源最为丰富,人工增雨潜力很大,是开展火箭人工增雨催化作业的最佳季节,春秋两季增雨潜力明显比夏季小,冬季最小;倒槽、副高后部、台风低压、高空低涡类和气旋类等系统最强,日降雨量和单位面积降雨量明显比其它系统大,尤其对蓄水型火箭增雨作业十分有利。     

2000年以来中国大陆5级以上地震近源区的相继发震特征与预测

通过对中国大陆除新疆和东北深震区以外的主要地区2000年以来5级以上地震活动特征的研究发现,5级以上地震近源区的相继发震是某些区域地震活动的重要特征。依据这一特征可以对今后研究区内5级以上地震的后续地震作中期预测。     

震群精定位问题讨论

本文利用一组高精度数字记录台站在新西兰北岛附近观测得到的一个地震群资料,选用合适的地壳结构,合理控制造成误差的因素,应用偏振技术提高地震波震相判定的分辨率,最后反演计算获得震源的定位解.虽然这个震群仅发生在15 km长的小条形区域内,由于较高的定位精度,能较清晰地反映出火山地区地震活动的特点,尤其是深度分布图像表现了一种非任意性.     

Thermodynamic conditions of framework grain dissolution of clastic rocks and its application in Kela 2 gas field

Feldspar and clastic debris are the most important constituent framework grains of sedimentary clastic rocks and their chemical dissolution plays an essential role in the formation and evolution of the secondary pore in the reservoir rocks. On the basis of thermodynamic phase equilibrium, this study investigates the chemical equilibrium relationships between fluid and various plagioclase and K-feldspar in diagenesis of the sediments, particularly, the impact of temperature and fluid compositions (pH, activity of K+, Na+, Ca2+ and so on) on precipitation and dissolution equilibria of feldspars. Feldspar is extremely easily dissolved in the acid pore water with a low salinity when temperature decreases. The dissolution of anorthite end-member of plagioclase is related to the Ca content of the mineral and the fluid, higher Ca either in the mineral or in the fluid, easier dissolution of the feldspar. Moreover, the dissolution of albite end-member of plagioclase is related to Na of both the mineral and fluid,