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991.
The short term human exposure studies conducted on populations exposed to high concentrations of inorganic arsenic in soil have been inconsistent in demonstrating a relationship between environmental concentrations and exposure measures. In Australia there are many areas with very high arsenic concentrations in residential soil most typically associated with gold mining activities in rural areas. This study aimed to investigate the relationship between environmental arsenic and urinary inorganic arsenic concentrations in a population living in a gold mining area (soil arsenic concentrations between 9 and 9900 mg kg(-1)), and a control population with low arsenic levels in soil (between 1 and 80 mg kg(-1)). Risk factors for increased urinary arsenic concentrations were also explored. There was a weak but significant relationship between soil arsenic concentrations and inorganic urinary arsenic concentration with a Spearman correlation coefficient of 0.39. When participants with greater than 100 mg kg(-1) arsenic in residential soil were selected, the coefficient increased to 0.64. The geometric mean urinary inorganic arsenic concentration for the exposed group was 1.64 microg L(-1) (相似文献   
992.
Urban Metal Management The Example of Lead   总被引:1,自引:0,他引:1  
The metal metabolism of an urban region, the City ofVienna, was investigated to discuss urban metal management strategies in view of environmental protection and resource conservation. About 90% of the metal stock is located in Vienna's buildings and infrastructure, whilst only 10% is in the landfills. The city stock represents a potential source for diffusive emissions. However, the control of the current environmental policy concentrates mainly on landfill emissions. Diffusive emissions resulting from the losses over the use of metal containing goods in the city are widely dispersed and cannot be easily controlled due to numerous non-point sources. First investigations indicate that for certain applications, the diffusive stock emissions are as significant as other sources. At present, Vienna's known diffusive and point source lead emissions into air and water are about 40 to 50 times higher than comparable past loadings from geogenic Vienna. Furthermore, a life cycle approach from acid car batteries indicates that sustainable lead management should consider flows and stocks in the hinterland of the city too. The city metal stock also represents a potential resource. Leaded water pipes built-in in Vienna's city stock have the potential to produce 1.6 million traditional car batteries. In future such city mining strategies can partly replace ore mining.  相似文献   
993.
Landscape Metrics for Assessment of Landscape Destruction and Rehabilitation   总被引:24,自引:1,他引:23  
This investigation tested the usefulness of geometry-based landscape metrics for monitoring landscapes in a heavily disturbed environment. Research was carried out in a 75 sq km study area in Saxony, eastern Germany, where the landscape has been affected by surface mining and agricultural intensification. Landscape metrics were calculated from digital maps (1912, 1944, 1973, 1989) for the entire study area and for subregions (river valleys, plains), which were defined using the original geology and topography of the region. Correlation and factor analyses were used to select a set of landscape metrics suitable for landscape monitoring. Little land-use change occurred in the first half of the century, but political decisions and technological developments led to considerable change later. Metrics showed a similar pattern with almost no change between 1912 and 1944, but dramatic changes after 1944. Nonparametric statistical methods were used to test whether metrics differed between river valleys and plains. Significant differences in the metrics for these regions were found in the early maps (1912, 1944), but these differences were not significant in 1973 or 1989. These findings indicate that anthropogenic influences created a more homogeneous landscape.  相似文献   
994.
2000 years of mining activity at Wiesloch, Germanyleft behind a legacy of mining wastes, some of which haveextremely high contents of toxic elements like As, Cd, Tl,Sb, Pb and Zn. To evaluate their long-term impact ondifferent environmental compartments, the detailedenvironmental monitoring presented here focused on themineralogical and chemical characterization of thedifferent waste materials, consisting of dumpings with orefragments, flotation tailings and medieval metallurgicalslags. Leaching experiments with these materials, usingeluents of different compositions and pHs were carried outto assess the conditions governing the mobilization and re-fixation of these species. It was shown, that the carbonatehost rock of the mineralization, the loess blanket coveringthe area and the organically rich municipal sewage sludgesdeposited on top of the tailings, represent potentialbarriers to the dispersion of toxic elements over a muchlarger area. Moreover, particulate emissions from thesteep, unvegetated escarpments of the tailing heapsrepresent a continuous thread to the environment.  相似文献   
995.
西部开发中的煤矿区生态环境保护与重建问题   总被引:4,自引:0,他引:4  
杨梅忠 《重庆环境科学》2001,23(2):24-25,29
分析了西部尤其是西北地区煤矿区生态环境坡坏的现状,确定了矿区重庆重建工程的目标,提出了矿区生态环境保护与重建的具体措施。  相似文献   
996.
997.
东川是依托矿产资源开发利用而兴建起来的城市,其经济结构属于典型的矿业依赖性经济,随着铜资源的耗竭,经济发展停滞,城市散失可持续发展能力。矿业城市的经济发展,关键是将单一的矿业经济转化为矿产业与非矿产业并举的多元型经济结构。现以云南省昆明市东川区为例,对其发展特征进行分析,揭示矿业城市的发展对策,为此类城市的发展提供思路。  相似文献   
998.
为了保证列车在轨道上安全运行,铁路部门采用动态检测和静态检测两种方式对铁路轨道进行检查。笔者针对现有铁路轨道检测方式,提出根据检测数据评定轨道质量状态的方法。该法采用数据仓库技术存储检测数据,给出检测数据存储的双重粒度模式和数据分割模式。从时间和空间两个方面对检测数据进行分析,采用轨道局部状态、整体状态、超限点重复率和重点地段分析的方法。将轨道数据分为时间维、地理维、类别维3个维度,运用星型模式对轨道检测数据进行数据挖掘,发现轨道变化规律。将上述方法应用到南疆工务管理信息系统中,取得了较好的实用效果。  相似文献   
999.
矿区浅层地下水污染机理探讨   总被引:1,自引:0,他引:1  
通过对煤矿建设项目和发展规划项目做的环境影响评价和对重点煤矿的现场调查,揭示了矿区浅层地下水污染的内在形成机理:开采引起地表沉陷是主导因素;地下水位埋深浅,潜水含水层下伏的隔水层稳定,只变形而不破裂是客观条件;地下水变成地表水,从而改变水的存在形式,致使水体极易遭受强烈的污染则是根本原因。针对地下水的保护问题,提出具体的对策和办法:加强矿区的环境管理、及时回填采煤沉陷坑,加强对浅层地下水的利用和人工降低地下水位等措施。上述措施如与煤矿建设项目同时实施,则煤矿区的地下水安全、环境保护都会实现。  相似文献   
1000.
矿山事故具有突发性,企业作为第一响应者,只有建立了完善的应急体系,才能够确保采取及时有效的措施进行事态控制和人员救治。矿山企业完整的应急体系由组织管理、运作机制、制度建设和保障系统构成。本文针对矿山企业的特点,系统的提出了应急体系四个构成部分的详细建设要素,研究结果为矿山企业进行应急管理体系建设提供了科学依据。  相似文献   
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