Seismic vulnerability of Kuwait and other Arabian Gulf countries: information base and research needs     

F. Bou-Rabee  E. VanMarcke 《Soil Dynamics and Earthquake Engineering》2001,21(2):817

This paper points to the need for seismic risk and vulnerability assessment of infrastructure systems, most notably tall structures and coastal facilities, in Kuwait and other Arabian Gulf countries. Building codes in the region currently lack seismic provisions, despite evidence of a potential threat from large-magnitude earthquakes originating from the southern part of the Zagros fold belt. The historical record of Iranian earthquakes that may have caused significant ground motion in the Gulf region is examined, as are reports of coastal damage from tsunamis. Various specific tasks, expected to constitute research priorities of a Joint Center for Risk Research, a cooperative research program involving Princeton and Kuwait Universities, are outlined.  相似文献   

甘肃省东部旱作区土壤水分变化规律的研究   总被引：13，自引：1，他引：13  

仇化民  邓振镛 《高原气象》1996,15(3):334-341

甘肃省东部旱作区的气候条件，降水补给作用及作物生长发育状况的特殊性，导致土壤水分具有独特的时空分布规律，麦田２ｍ土层水分的周年变化呈一峰一谷型，可划分为旱季失墒消耗阶段和雨季蓄墒贮水阶段；其垂直变化呈“Ｓ”型，可划分为水分多变层、过渡层及稳定层。  相似文献   

三江平原沼泽地碳循环初探   总被引：35，自引：1，他引：35  

马学慧  吕宪国 《地理科学》1996,16(4):323-330

在三江平原多年考察与研究的基础上，通过典型沼泽的定位观测，估算了三江平原沼泽土壤中的碳储量，探讨了沼泽植物对大气ＣＯ２的固定，碳素自沼泽土壤向大气的转移，沼泽近地气层ＣＯ２流，以及沼泽植物－土壤－大气之间的碳素流动。  相似文献   

ANALYSIS OF SOIL EROSION CHARACTERISTICS AND SEDIMENT SOURCES FOR THE YANTZE THREE GORGES REGION     

SHI Deming  YANG Yansheng  LU Xixi  and LIANG Ying 《国际泥沙研究》1992,(2)

In this paper the researches made in 1981-1990 have identified that the annual soil loss in the Three Gorges region is 157 million t. and the annual incoming sediment load of the Three Gorges reservoir is 40 million t. Soil erosion increases with the destruction of vegetative cover and its subsequent evolution. The annual amounts of sediment erosion for forest land, shrub land, grassland and farmland make up respectively 6.19%, 10.76%, 23.05% and 60% of the total erosion of the Three Gorges region; the quantities of incoming sediment load to the Yangtze River from the above four types of land account for 5.95%, 12.42%, 35.46% and 46.1 % of the total amount of sediment transported to the reservoir. The farmland of offers the main source of sediment. Gravitational erosion produces more bed loads, which will present serious threat to the Three Gorges Project if entering the reservoir. Resettlement of people to the upper parts of the mountainous areas for agricultural production will increase the sediment yield of the Three Gorges region by 10-20 million t and increase the incoming sediment of the Yangtze River by 50-60 million t. Consequently, it is necessary to make a realistic assessment of the soil erosion in the Three Gorges region.  相似文献   

Historical geomorphology and pedology of the Gandak Megafan,Middle Gangetic Plains,India     

R. Mohindra  B. Parkash  J. Prasad 《地球表面变化过程与地形》1992,17(7):643-662

The Gandak megafan of eastern Uttar Pradesh and northwestern Bihar lies in the Middle Gangetic Plains. The Gandak River has shifted about 80 km to the east due to tilting in the last 5000 years. This has created a soil chronoassociation similar to the chronosequences found on some flights of river terraces. This chronoassociation has five members, QGD1-5. They are distinguished on the basis of profile development, clay mineralogy and calcium carbonate content. Chlorite transforms to vermiculite on a large scale from QGD1 to QGD3 and decreases drastically in member QGD4. Kaolinite and interstratified kaolinite-smectite are abundant in the older members of the chronoassociation. The youngest soils (QGD1:? < 500 b.p.) are found on the floodplains of the major rivers. QGD2 soils, like those of the Young Gandak Plain, date from? > 500 b.p., while QGD3 soils, like those on the Older Gandak Plain and Old Rapti Plains date back to 2500 b.p. QGD4 soils, like those on the Oldest Gandak Plain, are dated as? 5000 years b.p., whilst the oldest QGD5 soils, as on the Old Ghaghra Plain and Ganga-Ghaghra Interfluve, date back to 10000 b.p. These soils, which include pedogenic calcite and a? saline epipedon, indicate a dry climatic spell during the period 9000-11000 b.p. Faults developed on the megafan are not related to the basement structures.  相似文献   

Geotechnical properties of a chemically stabilized soil from Malaysia with rice husk ash as an additive   总被引：1，自引：0，他引：1  

F. Haji Ali  A. Adnan  Chew Kam Choy 《Geotechnical and Geological Engineering》1992,10(2):117-134

Summary The stabilization of Malaysian soil by mixing with rice husk ash, a locally available waste material, to improve its engineering properties is described. Stabilizing agents, i.e. cement and lime, were added to produce the reaction products which are responsible for the enhancement of the engineering properties. Based on the strength development, it seems that lime is the more effective stabilizing agent. However, the cheap waste material can be used as partial replacement for the more expensive cement in the cement-treatment of the soil. A durability study was carried out to evaluate the effectiveness of this stabilization method.  相似文献   

亚热带山地土壤的地球化学特征及其与新构造运动的关系   总被引：1，自引：1，他引：1  

吴次芳  陆景冈等 《地理学报》1992,47(1):6-11

对亚热带峨眉山、天目山和凤阳山的列样品研究表明，高、低海拔土壤在矿质风化与淋溶、氧化铁富集与转化、粘粒矿物类型及分布等方面均酷为相似，而这些地球化学特性在相同温差水平带的土壤上却有明显区别，由此推算的新构造运动强度与前人研究结构基本一致。这对阐明山地土壤的发生分类及拓宽新构造运动研究方法等有一定参与价值。  相似文献   

不同覆盖条件对土壤水热分布影响的计算机模拟Ⅰ——数学模型   总被引：8，自引：0，他引：8  

隋红建  曾德超  陈发祖 《地理学报》1992,(1)

本文建立了用于数值解的不同覆盖条件下土壤二维水热运动数学模型。该模型中多孔材料覆盖层(砂砾、秸秆等)被当作传热多孔介质处理,对水分传输的影响被当乍具有一定阻力的阻挡层处理,且将油纸、塑膜及土面增温剂等均视为薄膜类材料。省略了许多假设条件,因而使覆盖效应的研究建立在更加科学的基础上,可以更为深入地了解覆盖层在不同气候条件下对土壤水分蒸发、入渗及地温影响机理和程度。为综合评价和选用农用覆盖材料及其参数提供了手段。  相似文献   

利用马氏过程模拟和预测土壤侵蚀的动态演变─—以安徽省岳西县为例     

李德成  徐彬彬  石晓日 《遥感学报》1995,(2)

本文根据安徽省岳西县１９５８－１９８２－１９９２年三个时期的遥感资料所编制的土壤侵蚀图，用点数转化法定量地分析岳西县上述两个阶段侵蚀演变和浸蚀类型之间的相互转化状况，确定相应的初始状态下（１９５８和１９８２）的转移概率矩阵，应用马尔科夫过程摸拟和预测岳西县土壤侵蚀及其格局的动态演变过程和未来演变趋势。  相似文献   

全球冻融地区土壤是重要的N₂0释放源的综合分析   总被引：3，自引：0，他引：3  

朴河春  刘广深 《地球科学进展》1995,10(3):283-288

Ｎ２Ｏ是重要的温室气体之一，它是微生物硝化作用和脱氮化作用过程的产物。有多种释放源，其中土壤圈是重要的释放源之一。在影响Ｎ２Ｏ释放通量的诸多因素中温度是关键因素之一。本文根据土壤冻融加强有机质矿化作用，以及对微生物群体产生非生物应力的性质，结合冻融地区土壤和冻土带湿地所具有的特征，进行综合分析，论述冻融地区土壤是重要的Ｎ２Ｏ释放源。  相似文献