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111.
矿山正常的生产经营活动势必形成一定的矿山地质环境问题。为全面贯彻生态文明思想,牢固树立“绿水青山就是金山银山”的理念,按照恢复生态、兼顾景观总体要求,因地制宜、多措并举,扎实开展废弃露天矿山地质环境修复。依据矿山地质环境保护与恢复的相关规范与要求,以汶川某废弃露天矿山为例,从矿山环境角度介绍了矿山地质环境的影响因素,开展矿山斜坡整体稳定性、采场边坡稳定性、弃渣堆稳定性及地形地貌景观破坏等地质环境影响评价,划分治理重点、次重点和一般3个基本的矿山地质环境保护与恢复防治区。结果表明: 矿山斜坡及弃渣堆现状基本稳定、采场边坡稳定性较差、地形地貌景观影响和破坏程度中等; 研究区矿山地质环境保护与恢复治理可划分为一般防治区和较严重防治区,其中一般防治区面积约554 m2(矿区无因采矿活动诱发的地质灾害,影响区内无居民居住,无威胁对象,矿区及周围地表水体未漏失,矿业活动对水土环境影响程度为影响程度小,未影响到矿区及周围生活供水)、较严重防治区面积186 m2(矿区与影响区地质灾害发生可能性小,地形地貌景观影响和破坏程度较严重)。针对评价结果提出的“坡面浮石清理+清除建筑垃圾、块石+植被重建”等修复建议,为同类型矿山绿色开采及地质环境保护措施提供了的重要技术参考依据。 相似文献
112.
Lead-210 methods have been used to establish a chronology of sedimentation extending back almost 80 years in Black Mountain Lagoon near Guyra on the New England Tablelands of north-eastern New South Wales, Australia. Estimates of the direct atmospheric fallout of unsupported 210Pb and historical records of the pattern of phosphorus input to the lake provide support for the 210Pb chronology. The sediments in the lake record an episode of disturbance which took place prior to c .1916, but after c .1790-1860. Since then, however, the site-specific rate of minerogenic sedimentation has been maintained at a relatively low and constant level of 0.93 kg m-2 a-1. [Note: the following symbols are used in this paper: a = year (annum), and d min-1 g-1 = radioactivity (spontaneous nuclear disintegrations per minute per gram of material).] This is despite major shifts in land use and intensification of agriculture, despite the occurrence of significant floods and droughts, and in the absence until recent times of the application of soil conservation practices. These rates may be contrasted with rates of 0.023 kg m-2 a-1 from the period 12.3-5.6 ka. These are at least an order of magnitude lower than those of the twentieth century. The lake sediments preserve evidence of the use of agricultural chemicals on the catchment during the twentieth century. These include phosphorus, zinc, arsenic and lead. Soils and sediments may act as long-term toxic stores for such chemicals, a problem often overlooked in rural areas. 相似文献
113.
合成了新型席夫碱试剂3,5-二溴水杨醛缩甘氨酸(DBSAGLY),建立该试剂荧光度法测定微量Zn(Ⅱ)的新体系,在pH=7.0~8.0时Zn(Ⅱ)与DBSAGLY形成1∶1的络合物,络合物最大激发和发射波长分别为λ 相似文献
114.
115.
矿产资源过度开发造成了严重的环境污染,可持续发展面临严峻挑战,矿山治理迫在眉睫。遥感信息提取技术能够便捷地获取矿山开发信息,为矿山治理提供依据。然而,目前信息提取的精度和自动化程度仍有提升空间,并且就矿产类型而言,关于石灰岩矿开采信息提取的研究甚少。针对以上现状,本文以唐山市的一处灰岩矿山为例,以Landsat-8影像作为基础数据,通过计算不同地物的纹理信息,包括地物均值、方差、信息熵、偏离度和数据范围,构造了能够突出露天灰岩矿开采区域的纹理指数模型(texture variance index,简称TVI)。结合已有的光谱和空间特征,设定准确的阈值并建立决策树,以面向对象方法为依托,进行露天灰岩矿山开采边界的信息提取。结果表明,将纹理方差指数作为灰岩矿山开发信息提取的规则之一,总体精度、用户精度和Kappa系数与原有决策树相比皆有所提高。以文中灰岩矿开采范围提取结果为基础,根据高分辨率影像的纹理特征,进一步实现了新矿区与待复垦旧矿区的分类,总体精度约为0.916。 相似文献
116.
为研究青藏高原金属矿山勘探、开采、闭坑阶段不同开发阶段河流重金属污染的严重程度,通过野外调查,室内测试分析,对比5个金属矿山河流重金属元素含量、污染指数沿程变化,得出以下结果:(1)勘探阶段和闭坑后河流水质污染较小,开采阶段矿业活动对河水水质污染较大。(2)As、Pb、Cd、Cu和Zn五种元素是金属矿山的特征污染物。开采矿区中德尔尼铜矿区、下柳沟铅锌矿、甲玛矿区河流均有重金属元素污染,微碱性环境中德尔尼铜矿区,主要污染物为As,单项污染指数为0~10.6;下柳沟铅锌矿Pb、Cd、Cu和Zn元素单项污染指数分别为0.2~2.1、0~55、0.4~24、0.3~1550;偏酸性环境中甲玛矿区的特征污染物主要为Cu、Cd。其中Cu、Cd单项污染指数为0~4174、0~4;勘探矿区大场金矿、闭坑矿区罗布莎铬铁矿区河流未出现污染元素。(3)青藏高原5处典型的高海拔山地矿山河流由于稀释作用重金属流经2km后达到安全水平,研究结果可为青藏高原矿山开采中河流水环境保护提供参考依据。 相似文献
117.
主要介绍了国土资源"一张图"系统手持GPS移动监管平台的构成与建立等内容,阐述了手持GPS技术在露天矿山边界范围监管中的应用及与传统方法比较所具备的优势,手持GPS技术在今后的国土资源露天矿山监管中将会得到普及应用。 相似文献
118.
Ilse Gräber Jørgen F. Hansen Svend E. Olesen Jens Petersen Hans S. Østergaard Lars Krogh 《Geografisk tidskrift / udgivet af Bestyrelsen for Det Kongelige danske geografiske selskab》2013,113(2):15-22
Geografisk Tidsskrift, Danish Journal of Geography 105(2):15–22, 2005 The change of Cu and Zn concentrations in Danish agricultural soils was studied in areas with intensive pig production. Cu and Zn are found in pig manure as the metals are added to pig feed as growth promoters. The changes in concentrations of total and 0.02 MEDTA extractable Cu and Zn in soils from 1986 to 1998 were determined from samples taken at two depths (0–25 cm and 25–50 cm) from 73 sites. Pig manure and mineral fertilizer was added to 60 sites whereas fertilizer only was used on 13 sites. During the survey period soil Cu concentrations increased in both depths but mostly in the sites where pig manure was added. Furthermore, the results indicated that some plant-available Cu and Zn were transported from the topsoil to the subsoil. No significant change in soil Zn concentration was found although a slight reduction was observed. Comparing soil metal concentrations observed in 1998 to the total pig manure application in a 12-year period, it was observed that application of manure caused an accumulation of Cu and of Zn in the upper 50 cm soil. The accumulation rates correspond to the Cu and Zn concentrations in the pig manure. 相似文献
119.
采空区群的稳定性分析是一个复杂的地质问题,而在区域内存在一种群效应。准确地掌握采空区群的三维形态和空间的相对位置是进行稳定性分析的前提。以石人沟铁矿为背景,利用空区探测系统(CMS)对采空区进行了精密探测,并对探测数据进行处理和转换,在此基础上,应用3Dmine建立了采空区群的三维空间模型,经过进一步处理实现了与FLAC3D的耦合,建立了三维数值计算模型。根据计算结果对采空区群区域的应力场、位移场进行了分析,对群区域内的群效应进行了阐述。在此基础上对群区域地表位移进行了分析,确定了地表最大位移面积和采空区水平面积的比值。研究结果表明,区域内的群效应使应力和位移较单个采空区时都有了较大增加,且增加幅度并不是单纯的叠加,这种效应加剧了采空区的危险等级,将CMS、3Dmine和FLAC3D三者的优势结合起来,为采空区群得稳定性分析提供了一个准确而有效的途径。 相似文献
120.
The mining industry has made outstanding contributions to China’s economic and social development, but a series of environmental problems remain. As Green Mines and ecological civilization concepts are put forward, the relationship between people and nature is receiving more attention, and especially mining ethics. Present construction standards encompass legal mining, management standardization, comprehensive utilization, technological advancement, energy saving and waste reduction, environmental protection, land reclamation, harmonious community and enterprise culture. As at 2014 the Chinese Ministry of Land and Resources had published 661 Green Mines. Here, we analyze the present situation and prospects of Green Mines in China by the distribution from regional and mine type perspectives. Green Mines are nearly spread over every province and mine type, but Eastern China participated earlier than other areas. We discuss constructing Chinese mining ethics on the basis of traditional ethics and Western ecological ethics as theoretical foundations and practices. We consider that the significance of building Chinese mining ethics in Green Mine construction includes promoting social responsibility, improving environmental protection awareness and accelerating society development. Under the guidance of Chinese mining ethics we propose mining enterprise development models for the future, such as comprehensive utilization, circular economy and community harmony. 相似文献