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91.
92.
南水北调西线雅砻江调水工程温波引水枢纽坝址径流计算的研究 总被引:1,自引:2,他引:1
南水北调西线雅砻江调水工程(简称西线调水)是从长江的一级支流雅砻江上游区引水至黄河源头地区的跨流域调水工程,是补充黄河水资源不足与解决我国西北和华北部分地区干旱缺水的重大战略措施,由于引水枢纽坝址缺乏实测水文资料,我们依据附近孜水文站实测资料,采用一些非确定性的数理统计模型来计算温波引水坝址的设计年径流量,并对计算成果进行了合理性分析,结果表明,上述计算成果基本反映了温波引水坝址径流变化的客观情况,从而为南水北调西线雅砻江调水工程缺乏实测水文资料地区的水文计算提供了科学依据。 相似文献
93.
Roland Otto 《Hydrogeology Journal》2001,9(5):498-511
In the southeastern Holstein region, located to the east of the metropolitan zone of Hamburg, northern Germany, a groundwater
investigation program was conducted from 1984 to 2000 by the State Agency for Nature and Environment (Landesamt für Natur
und Umwelt, LANU) of Schleswig-Holstein, Germany, with the aim of providing long-term, ecologically acceptable groundwater
management plans for the region. The focal point of the investigation comprised the determination of groundwater recharge
rates. The investigation method was based on the transfer of available lysimeter results from other regions to comparable
regions within the area studied. With the help of lysimeter equations, potential amounts of percolation water were calculated.
The groundwater recharge rate was then determined after subtraction of the surface runoff which was calculated for the entire
area. All computations were performed with a spreadsheet program. Groundwater recharge rates were calculated for two areas.
One consisted of roughly determining groundwater recharge rates for the total region (1,392 km2) of southeastern Holstein. The overall goal of these investigations was to identify potential areas of water exploitation.
Areas in which groundwater recharge rates are high and groundwater outflow is low are particularly suited to water exploitation,
since inflow rates into deeper aquifers are high. These areas are located on the flanks of the Elbe and Stecknitz River valleys.
Subsurface groundwater runoff to these lowlands would be reduced through groundwater withdrawal. However, the resulting decline
in shallow groundwater tables would be so small that it would have no detrimental ecological effects. Groundwater recharge
rates were also calculated for a 110-km2 area in the outskirts of Hamburg (Grosshansdorf model area) which is intensively developed for water supply. These investigations
showed that the amount of groundwater recharge is already being withdrawn to a large extent. Approximately 65% of the recharge
rate is currently withdrawn by the waterworks in this area, thus making further increases in exploitation rates unjustifiable
from an ecological point of view.
Electronic Publication 相似文献
94.
Won Bae Kim 《GeoJournal》2001,53(1):47-56
The historic summit between the leaders of the two Koreas in June 2000 provided a new opportunity for inter-Korean dialogue. Despite many uncertainties regarding the form and substance of inter-Korean economic cooperation, Korean people believe that inter-Korean economic cooperation will expand and eventually lead to economic and territorial integration of the two Koreas. This essay discusses the progress and issues of inter-Korean economic cooperation including infrastructure development. In particular, the essay examines long-term planning issues surrounding the territorial integration of the Korean peninsula and their implications for balanced development. With the German case of economic integration as a point of reference, the essay points out a few strategic problems involved in inter-Korean economic cooperation and suggests an alternative strategy to achieve balanced development. 相似文献
95.
Yong-Woong Kim 《GeoJournal》2001,53(1):5-15
In the early stages of economic development in Korea, national territorial planning was used as a policy tool to guide spatial structure and to provide physical infrastructure for urban and industrial development. Such a top-down approach was inevitable because Korea maintained the centralized political and government system until the early 1990s. Circumstances, however, have changed recently since the 1990s with progress in democratization and localization. In addition, forces of globalization are making significant impacts on the parameters of national territorial planning. Reflecting these changes in both internal and external conditions, the Fourth National Territorial Plan (2000–2020) has adopted a different approach from the past three territorial plans. This paper reviews the socio-economic background that necessitated such changes in approaches to national territorial planning. A major thrust of the Fourth Plan, a focus on emergent or anticipated planning issues in Korea, is discussed. Finally, the paper examines the rationale for long-term strategic planning in the highly fluctuating situation facing Korean society in the new century. 相似文献
96.
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98.
A unique historical data set describing the 142 storms each producing losses in excess of $100 million in the United States during the 1950–89 period were analyzed to describe their temporal characteristics. The storms caused $66.2 billion in losses (in 1991 values), 76% of the nation's insured storm losses in this period. These extreme storm catastrophes (SCs) were most prevalent in the south, southeast, northeast, and central U.S., with few in and west of the Rocky Mountains. Storm incidences were high in the 1950s, low in the 1960s-early 1970s, and increased in the 1980s. Losses due to SCs peaked in the 1950s, again in the late 1960s, with a lesser peak after 1985. The areal extent of storm losses peaked after 1975 and was least in the 1960s. The temporal variations of the three storm measures (incidence, losses, and extent) did not agree except when they all peaked in the 1950s. Regionally-derived time distributions of SCs showed a marked north-south differences in the United States with a U-shaped 40-year distribution in the northern half of the nation, and a relatively flat trend until a peak in the 1980s in the southern regions. The temporal distributions of hurricane-caused catastrophes differed regionally with occurrences in the prime areas, the southern, southeastern, and northeastern U.S., each quite different. Temporal distributions of thunderstorm and winter storm catastrophes were regionally more uniform. 相似文献
99.
100.
城市地质信息系统建设的目标与解决方案 总被引:20,自引:0,他引:20
城市地质信息系统建设的基本功能目标是:支持多源异构地质空间数据的存储、管理、提取、传输与交叉访问,实现地下地质结构与关系的表达、分析和过程的三维可视化,支持政府决策并开展相关领域的信息社会化服务。为此,应当将其纳入“数字国土”和“数字城市”工程的统一规划中去,一方面借鉴地矿点源信息系统的设计思路与方法,研发并建造主题武的“城市国土资源基础数据平台”,以及相关的决策支持系统和服务应用系统;另一方面运用“多S”集成技术、联邦数据库技术、数据仓库技术、三维可视化技术和计算机网络技术,整合各种已有的和新建的多源异构的数据库、图形库、知识库、方法库、模型库和管理系统、决策系统。在具体设计时,可以将客户机/服务器(C/S)结构与浏览器/服务器(B/S)结构结合起来,并按市(局)—县(区、分局)两级联网的构架进行设置。 相似文献