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王埝沟铁矿床为我国已探明的大型铁矿床,正处于开采初期阶段,年产铁精矿71.33万t,服务年限37.5a。矿山运营期间产生了废石、尾砂、锅炉灰渣等大量的固体废弃物。该文通过对废石、尾矿的伽玛能谱测量分析认为:废石和尾砂的放射性含量较低,开采、选冶过程及固体废弃物的综合利用,不会对人体及环境造成放射性危害。通过对废石、尾矿以及锅炉灰渣毒性浸出实验结果的分析研究,认为废石、尾矿为第Ⅰ类一般工业固体废物,其淋溶水不会导致地下水水质恶化及土壤的污染;锅炉灰渣属于第Ⅱ类一般工业固体废物,其存储场应按照Ⅱ类场要求执行,其淋溶水也不会导致地下水水质恶化及土壤的污染。该文对主要固体废弃物(废石和尾砂)的岩性组成、主要矿物特征和用途进行分析研究,参考以往矿山利用成果,提出了综合回收利用的具体方向,如用于建筑材料、路基填料、玻璃生产原料、研磨材料、陶瓷原料、水泥、石灰生产原料、土壤改良剂或肥料、化工原料等。 相似文献
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民间小规模金矿混汞冶炼活动因缺乏环保措施常常造成周围环境严重的汞污染,目前已被认定为全球最大的人为汞污染排放源。福建省德化县山区土壤汞含量异常升高和该地区民间小规模金矿冶炼活动密切相关,对当地土壤总汞、大气总汞污染分布及土壤表面汞释放的调查研究表明:金矿区周边村子稻田土壤汞平均质量分数达(5.180±7.191)mg/kg,距金矿最近民间冶炼活动最集中的邱村稻田总汞质量分数平均值达到(15.658±12.726)mg/kg,随着距离金矿点越远民间冶炼活动减少,土壤总汞含量呈下降趋势。[JP2]区域大气总汞平均质量浓度为(36.4±24.3)ng/m3,邱村大气总汞质量浓度平均值(77.2±42.4)ng/m3;工作区4个土-气界面汞通量均值分别为:华口(109.6±55.9)ng/(m2h),邱村(97.1±36.1)ng/(m2h),大安(63.5±12.6)ng/(m2h),中仙(25.9±23.5 ng/(m2h)。因地形复杂,微气象条件差异及土地利用差异等综合因素制约,土壤汞含量与大气总汞含量、释放通量间没有显著相关关系,华口测点土壤释汞通量最大。工作区民间金矿冶炼活动历史造成当地环境的汞污染及其环境影响将长期存在。 相似文献
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《广东海洋大学学报》2016,(4)
通过16SrRNA基因特异扩增测序,对惠州大亚湾大辣甲岛和小辣甲岛附近海域14种造礁石珊瑚16SrRNA基因片段序列进行了比较分析。结果表明,该片段序列的平均A+T含量为63.5%,所有物种的序列碱基AT含量大于GC含量,序列都处于高度饱和的状态。14种造礁石珊瑚的平均遗传距离为0.179。采用NJ、ML和ME法构建系统发育树,结果显示蜂巢珊瑚科单独作为分支处于发育树的基部,而第二支分支包括菌珊瑚科、鹿角珊瑚科、滨珊瑚科和枇杷珊瑚科。裸肋珊瑚科的腐蚀刺柄珊瑚聚到了蜂巢珊瑚科中,与传统形态学分类存在差异,提示造礁石珊瑚表型的变异性可能对传统分类存在影响。 相似文献
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对雷州常见的3种滨珊瑚科珊瑚：澄黄滨珊瑚（Porites lutea）、灰黑滨珊瑚（Porites nigrescens）、普哥滨珊瑚（Porites pukoensis）,共32个样本的12S rRNA基因序列进行了PCR扩增和测序,研究其系统发生关系。结果显示,所得的3种珊瑚的12S rRNA基因长度在728～908 bp之间,G+C含量在34.3%～39.2%之间,遗传距离在0.004~0.019之间。利用邻接（NJ）法、最大似然（ML）法和不加权对群分析(UPGMA)法构建的系统进化树显示：3种珊瑚被分成了2个支系,澄黄滨珊瑚和灰黑滨珊瑚聚合在一个分支上,而普格滨珊瑚在另一支,这一研究结果与传统形态学分类研究的结果存在一定差异。 相似文献
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《广东海洋大学学报》2017,(4)
通过ITS基因特异扩增测序,对大鹏半岛海域46种石珊瑚ITS基因片段序列进行了比较分析。结果表明,该片段序列长度在674~806碱基对(bp)之间,A、T含量在40%~55.5%之间,大部分物种的序列碱基A、T含量小于G、C含量。46种造礁珊瑚的平均遗传距离为0.261。采用邻位连接(NJ)和最小进化(ME)法分别构建15种复合型珊瑚的5.8S r DNA系统发育树和28种坚实型珊瑚的ITS2系统发育树,结果显示15种复合型珊瑚的5.8S r RNA序列系统进化聚类结果较符合传统形态学分类结果,而28种坚实型珊瑚的ITS2序列系统进化聚类结果与传统形态学存在较大的差异,提示石珊瑚表型的变异性可能对传统分类存在影响。 相似文献
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研究长江经济带矿区土壤重金属污染特征,是完善长江经济带矿区环境保护措施的前提.在收集２０００ 年以来有关长江经济带矿区土壤重金属污染特征资料的基础上,统计分析了矿区土壤重金属元素含量,并分区评 价了污染特征.结果表明:从地区来看,长江经济带的 As,Cr,Ni,Zn,Cd平均含量以中游地区最高,Cu,Pb,Hg平 均含量以上游地区最高.从元素来看,Cd,Hg是长江经济带矿区土壤重金属元素污染的主要元素,上游地区２种 元素的地累积指数 平 均 值 分 别 为 ６．３２ 和 ７．０４;中 游 地 区 分 别 为 １６．９３,－１４．１９;下 游 地 区 分 别 为 －１８．４１ 和 －１０５．２３.从分布来看,w(Cd)均值大于１．５mg/kg的矿区均匀分布在长江经济带内,w(Hg)均值大于２mg/kg 的矿区分布在长江中、上游地区.为今后长江经济带矿区土壤重金属元素污染预防和治理制定了健康风险评估、 开展农产品安全研究、合理调控开发总量的策略. 相似文献
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《广东海洋大学学报》2021,(3)
【目的】筛选盾形陀螺珊瑚最佳的活体饵料。【方法】共设3个实验组和1个对照组,每组设置5个重复,进行为期45 d的喂食实验,测定不同饵料喂食条件下(轮虫、卤虫、小球藻)盾形陀螺珊瑚生长率、蛋白质含量、脂肪含量及脂肪酸组成。【结果】轮虫、卤虫、小球藻等三种饵料中,盾形陀螺珊瑚最适宜的活体饵料是轮虫,其钙化率、蛋白质含量及脂肪含量均高于其他两种饵料,其钙化率比卤虫组和小球藻组分别高出59.3%和420%,蛋白质分别高出66.7%和60.7%,脂肪含量分别高出18%和71.7%。脂肪酸结果显示轮虫喂食下珊瑚C24:1、C22:6两种脂肪酸比例偏低。【结论】轮虫是盾形陀螺珊瑚较合适的饵料载体,能够显著增加珊瑚的钙化率、蛋白及脂肪含量,但仍需进一步解决其长链不饱和脂肪酸缺乏的问题,为珊瑚提供更均衡的营养。 相似文献
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荒漠露天矿区植被受损评估及环境修复是近年研究的热点方向。为了研究新疆五彩湾地区矿产开发对矿区及周边荒漠植被的扰动影响,采用1990-2017年90景Landsat数据分析煤矿开发前后矿区及周边荒漠植被的时空变化特征,并定量分析矿区植被长势对气候变化、矿区扩张的响应。结果表明：① 2006-2013年矿区植被所受的扰动最大,在周边植被长势转好的情形下出现明显的退化,在1990-2006年和2014-2017年,扰动较小,矿区与周边植被长势变化一致;② 生长季的月度NDVI分析显示,矿区中心样区的植被经历了一个先退化后恢复的过程;③ 矿区开发对周边植被长势的扰动距离分别为“西-东”方向的-17~21 km和“南-北”方向的-13~23 km,其中2013年对植被的干扰距离最大;④ 冬春季降水是五彩湾矿区及周边植被长势转好的主要因素,虽然矿区一直处于扩张的状态,然而随着降水的增加和矿尘防护措施的加强,2014年来矿区植被长势转好,与周边植被变化趋于一致。本文的研究为干旱区露天煤矿及周边荒漠植被变化动态监测及矿区开采的扰动范围提供了准确的数据支持,便于矿区管理者合理制定相关环保法规及矿区管理办法,实施相关环境保护和污染控制等措施。 相似文献
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《国土资源导刊(湖南)》2015,(1):75-76,89
<正>一、技术类型该技术属于深井采矿技术。二、适用范围适用于深井开采矿山和井下高温高压开采条件的矿山。三、技术内容(一)基本原理该技术主要通过深井采场地压控制技术、深井通风系统优化及降温技术、深井缓倾斜复杂薄矿脉开采综合技术、深井全尾砂胶结充填新材料,实现废石充填采空区,减少采矿对地面环境的影响。具体做法:1采用全尾砂胶结充填法改变薄矿脉采矿方法,实现地压控制;2利用空区充填,在中部34中段、35中段建立隔离层,并开掘2#主提升井进风,形成上下两个采区的分区通风系 相似文献
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王明远 《中国地理科学(英文版)》1993,3(4):376-380
We have made progress in medico-chemical geography as follows: the correlative law of organism with geochemical environment; the geochemico-ecological classification of chemical elements; the types of formative cause of biogeochemical provinces in China; the parabolic correlation between contents of iodine in drinking water and prevalence rate of endemic goiter; the discovery and proof of the low selenium zone in China; the successive discovery of endemic fluorosis of the types of pollution from burning coal, drinking high fluoride tea and high fluoride table salt from the year 1978; the study on chemical geography of schistosomiasis and the compilation of the Atlas of Endemic Diseases and Their Environments in the People's Republic of China. 相似文献
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随着信息社会的发展，新技术和新媒体的出现必然影响学校现代教育的发展。通过阐述发展学校电化教育的应注意的问题，探讨了解决问题的方法。 相似文献
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We used long term monitoring data to evaluate changes in abundance and species dominance of small-jellyfish (collected with zooplankton net whose bell diameter was less than 5 cm) between 1991 and 2009 in the Jiaozhou Bay, China. Zooplankton samples were vertically towed with conical plankton net from near-bottom to surface, identified microscopically, and mapped in time-space using Grapher 7.0 and Surfer 8.0. Results show that the abundance of small-jellyfish throughout the bay had been increasing during 2001-2009 on average of 15.2 ind./m 3 , almost 5 times higher than that between 1991 and 2000. The occurrence of peak abundance shifted from spring to summer after 2000, and two peaks appeared in spring and summer, respectively, after 2005. Both the abundance and the frequency of blooms of small-jellyfish increased after 2000 in the bay. In addition, the biodiversity of jellyfish has increased significantly in recent years with a change in dominant species. Several new dominant species appeared after 2000, including Rathkae octopunctata in winter, Phialidium hemisphaericum in spring, summer, and autumn, Phialucium carolinae in spring, and Pleurobrachia globosa in summer and autumn, while some previous dominant species throughout the 1990s (Eirene ceylonensis, Zanclea costata, Lovenella assimilis, and Muggiaea atlantica) were no longer dominant after 2000. The abundance of small-jellyfish was positively correlated with the density of dinoflagellates, and the abundance of zooplankton. We believe that the changes in smalljellyfish abundance and species composition were the result of eutrophication, aquaculture and coastal construction activities around the bay. Concurrently, seawater warming and salinity decrease in recent decades promoted the growth and reproduction of small-jellyfish in the bay. 相似文献
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Community participation in forest resource management in Nepal 总被引：2，自引：1，他引：1
KeshavL.Maharjan 《山地科学学报》2005,2(1):32-41
Livelihood of the people in Nepal hills depends much upon forest resources in addition to farming as forest plays a critical role in the well being of the farming households where access to alternative sources, such as energy for cooking, nutrition for animals, materials for fertilizer and constructing materials for shelter, are limited. Thus, the well being of the people in the hills is directly affected by the management of these forest resources. This issue was addressed in this paper by examining the forest resource management practices and its effect on well being of rural people in two different stages in a village lying in the steep hill of Mahabharat Range in the southern hills of Kathmandu valley, Lalitpur District. The main ethnic/caste groups in the villageare Brahmin/Chhetri (high Hindu caste),Magar/Tamang (Tibeto Burmans) and Kami (occupational caste: cobbler). Currently there are four community forest users groups, with mixed ethnic membership, organized to manage the forest resources. The endowments, weak institutional settings, before 1990 helped the Bhramins, Magars and Tamangs to get access into the private forest endowment, which made them easy to get access to the forest resources, mainly fuel wood, fodder and timber in 1990 and enhanced their well beings. But the socially backward Kami could not get benefit from the institutions that existed during that time and had less chance to enhance their well beings. After the set up of different endowments during late 199os, i.e.,hand over of forest management to users groups in line with the concept of community forest,environment to use the forest resources became better for all the groups, along with the management of the forest. This enhanced the well beings of all the groups in the study village. However, the ability of Kami to use the forest resources to enhance their well beings was still lacking behind. The reason was partially due to the difference in endowments carried over from the endowments before 199o, and partly due to their occupational work and location of their settlements. 相似文献
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刘希林 《中国地理科学(英文版)》1995,5(3):275-287
ＲＥＣＥＮＴＤＥＶＥＬＯＰＭＥＮＴＳＩＮＤＥＢＲＩＳＦＬＯＷＲＥＳＥＡＲＣＨＩＮＩＴＡＬＹＭａｒｃｈｉＬｏｒｅｎｚｏ；ＴｅｃｃａＰｉａＲ．（ＩｎｓｔｉｔｕｔｅｆｏｒＰｒｅｖｅｎｔｉｏｎｏｆＨｙｄｒｏｌｏｇｉｃａｌａｎｄＧｅｏｌｏｇｉｃａｌＨａｚａｒｄ... 相似文献