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71.
《矿产资源法》颁布实施五周年,通过宣传贯彻,增强了广大干部、群众依法办矿的法制观念,推动了各项矿管工作的开展,依法办矿的矿山取得了采矿权,非法采矿的小矿山被关闭,违法行为受到查处,矿管部门的声望越来越高,促讲了依法治矿。宣传贯彻《矿产资源法》要领导首先学法,提高认识,加强领导,建立一支专兼结合的宣传队伍,采取多种形式有重点地进行宣传教育。我国、我省面临矿产资源形势是严峻的,浪费矿产资源的现象仍存在,要继续深入宣传贯彻《矿产资源法》。  相似文献   
72.
本文论述在新形势下地震台站体制、任务改革的必要性与可行性,认为地震台实行地震监测、科研、预报三结合和将单一观测型台站转化成观测--科研型台站系我国地震台站的发展方向。文中结合牡丹江等地震台的实践对三结合地震台站建设的实施办法和管理体制进行了讨论。  相似文献   
73.
线性规划在徐州地下水资源开发中的应用   总被引:1,自引:0,他引:1  
本文从地下水系统的观点出发,对徐州地区中寒武统—中奥陶统碳酸盐岩地下水系统进行了分析。并应用线性规划的原理和方法对徐州市西郊四个水源地地下水进行了水文地质计算。在规定水位允许降深的约束条件下,求得至2000年,该区地下水最大开采量为14万米~3/天及各水源地相应取水量的最佳分配。文中采用特定条件图解法计算多边界、多主井抽水干扰影响的方法,具有通用意义。  相似文献   
74.
Seismic risk of circum-pacific earthquakes I. Strain energy release   总被引:1,自引:0,他引:1  
Commonly used earthquake “whole process” frequency - magnitude and strain energy - magnitude laws are merged to obtain an analytic expression for an upper bound magnitude to regional earthquake occurrenceM 3, which is expressed primarily in terms of the annual maximum magnitudeM 1 and the magnitude equivalent of the annual average total strain energy releaseM 2. Values ofM 3 are also estimated graphically from cumulative strain energy release diagrams. Both methods are illustrated by application to the high seismicity of the circum-Pacific belt, using Duda’s (1965) data and regionalisation. Values ofM 3 obtained analytically, with their uncertainties, are in agreement with those obtained graphically. Empirical relations are then obtained betweenM 1,M 2, andM 3, which could be of general assistance in regional seismic risk considerations if they are found to be of a universal nature. For instance.M 3 andM 2 differ by one magnitude unit in subregions of the circum-Pacific.  相似文献   
75.
Nature-triggered hazards and disasters have traditionally been treated only from the lens of geophysical and biophysical processes, implying that the root cause of large-scale death and destruction lies in the natural domain rather than in a coupled human–environment system. Conceptually, the physical domain has been seen as discrete and separate from human entities, and solutions were sought in the technological intervention and control of the physical environment—solutions that often ended up being less effective than hoped for and sometimes even counter productive. At all levels, institutions have directed and redirected most of their financial and logistical resources into the search for scientific and engineering solutions without allocating due attention and resources towards the assessment of effects and effectiveness of the applications of such technological outcomes. However, over the last two decades, forceful criticisms of the ‘dominant’ technocratic approach to hazards analysis have appeared in the literature and consequently there has not only been a shift in thinking of causation of disaster loss in terms of human vulnerability, but also newer questions have arisen regarding distinguishing between the ‘physical exposure’ of people to threats and societal vulnerability, and linking them with propensity to hazards loss. Though the vulnerability/resilience paradigm has largely replaced the hazards paradigm within the social sciences and much of the professional emergency and disaster management communities, this shift of thinking has not progressed to much of the physical science community, decision-makers and the public, who have not yet accepted the idea that understanding and using human and societal dimensions is equally or more important than trying to deal and control nature through the use of technology. This special issue is intended to further the idea that the aspects of community and peoples’ power to mitigate, to improve coping mechanisms, to respond effectively, and recover with vigor against the environmental extremes are of paramount conceptual and policy importance.  相似文献   
76.
In this paper, a simple scenario and probabilistic approach is used to assess the potential groundwater risk due to proposed overdraft remedial actions in cone of depression, Jining City, China. Focusing on the concentrations of Chloride ions (Cl) and total hardness (TH), the impact of artificial recharge and reduced pumping on groundwater quality and quantity is analysed by using the three-dimensional finite difference groundwater flow and transport model, Visual MODFLOW, to simulate groundwater flow and transport within the study area based on scenarios, and utilizes SURFER software to map risk levels. Although 5, 10 or 15% reduced pumping with artificial recharge leads to more decrease in Cl and TH concentrations than the 25%, less volume increase is achieved for the remediation of land subsidence and other environmental problems in the cone of depression. The Cl concentrations in recovered groundwater are within the desired concentration of 200 mg/l; however, TH in some cases are above the maximum permissible limit of 500 mg/l, with an exceedence probability of about 0.67 for recharge and recharge with reduced pumping at 25%. The presence of fractures and hydrogeological complexity greatly determines impacts of remediation, and the 22% reduced pumping with artificial recharge offers an optimum strategy for overdraft remediation in the Jining cone of depression.  相似文献   
77.
岩体质量分级的风险分析方法   总被引:2,自引:0,他引:2  
提出了基于RMR岩体质量分级系统的岩体质量研究风险分析方法。该方法分析步骤如下 :(1)通过岩芯样品的现场观测和实验室试验获得分类所需的变量 ;(2 )统计分析拟合得出各变量的分布函数及参数 ;(3)运用Monte Carlo模拟方法获得 2万个RMR值 ,并将结果绘成岩体质量描述图 ;(4)利用以上结果作出岩体质量风险分析评价。该方法用于润扬长江公路大桥岩体质量评价研究获得良好效果  相似文献   
78.
三峡工程建成后枯水期运行的气候风险研究   总被引:2,自引:0,他引:2       下载免费PDF全文
通过蒙特卡罗试验, 探讨了三峡工程建成后枯水期运行风险的评估方法。以GCM模拟试验结果为未来气候情景, 随机模拟了三峡地区在该气候情景下枯水期月降水量分布; 建立了三峡地区月径流-降水模型和三峡水库调度模型; 初步分析了长江三峡工程建成后在当前气候背景和可能未来气候情景下的运行风险。结果表明, 三峡水库的运行对气候变化反应敏感, 春季和冬季的发电风险有明显改变。  相似文献   
79.
康慕谊  江源 《第四纪研究》2001,21(4):337-344
生态区评价是近年来出现在美国的一种新型区域生态系统管理方法的理论与实践科学研究,起始于美国总统森林会议(1993)后成立的森林生态系统管理评价组(FEMAT),目标是实现地区生态系统的科学管理.本文评介了生态区评价首项案例--美国西北太平洋沿岸区原始森林及其他各类森林经营管理方案的生态、经济、社会影响综合评价的科学与方法实践意义.指出FEMAT的生态区评价:1)迈出了生态区评价历史上坚实的第一步,实现了区域土地利用规划与生态系统管理方案从以行政疆域为准划分向以生态区域为准划定边界的转变;2)方案优化过程充分考虑区域生态、经济、社会的历史、现状与未来趋势等各方面,将科学、政策、管理融为一体,使之易于在实践中贯彻;3)促进了不同政府机构和利益团体间为实现资源开发与生态保育双重目标而共同协作.  相似文献   
80.
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   
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