Comparison of methods for measuring heavy metals and total phosphorus in soils contaminated by different sources

The relationships between the concentrations of zinc (Zn), lead (Pb), copper (Cu), nickel (Ni) and chromium (Cr) as measured by X-ray fluorescence analysis (XRF), aqua regia, and HNO₃ pressure digestion were studied in soil samples covering a wide range of heavy metal concentrations. The soils were contaminated by sewage sludge, exhaust depositions, river sediments of mining residues, and dump material. The question was addressed whether the source of heavy metals or other soil properties affect the relationship between these three methods. The aqua regia-digestible fraction of the five heavy metals reached on average 64% of the XRF-detectable content. The pressure accelerated HNO₃-digestible fraction of the five heavy metals was on average 71% of the XRF-detectable content; the respective phosphorus (P) fraction reached a median of 75%. This suggests that HNO₃ pressure digestion can also be used for characterizing the total P content of soils. Aqua regia extraction and HNO₃ pressure digestion gave similar values for Zn, Pb, and Cu, which dominate the heavy metal load of most contamination sources. Significantly higher Cr values were obtained by HNO₃ pressure digestion than by aqua regia extraction. Additionally, the Cr contents were affected by the source, e.g. sewage sludge had relatively high contents of aqua regia and HNO₃ pressure extractable contents in comparison to the XRF values. The element-specific relationships between the three methods were all highly significant. However, the respective multiple linear regression models were in most cases affected by soil organic carbon (C), in some cases by clay or soil pH.     

高速公路建设中不同类型弃土场的土壤流失特征

 以沪蓉西高速公路(上海至成都高速公路西段)湖北宜长段(宜昌至长阳县)弃土场为研究对象,通过观测天然降雨、土壤、植物和土壤流失量等因子,探讨不同类型弃土场的土壤流失特性。结果表明:1)降雨量与降雨强度的乘积(PI)和次降雨造成的单位面积土壤流失量(E)之间,表现出较好的一元正线性相关关系。在不考虑影响坡面土壤流失的其他因素的前提下,随着降雨量和降雨强度乘积的增加,土壤流失量逐渐加大。2)采取工程措施和生物措施综合防护,可以有效减少弃土场的土壤流失量。3)弃土场表土物质组成对土壤流失起着重要作用,表土受雨水冲刷,砾石含量会逐渐增大,土壤流失量逐渐减小。     

矿山复垦中污泥复混基质对三种木本植物生长的影响

为了探讨污泥、粉煤灰、煤矸石和土壤复混基质对柠条、紫穗槐和二色胡枝子幼苗生长的影响,以污泥与粉煤灰、煤矸石和土壤按一定比例混配成复混基质,D1处理(污泥∶粉煤灰∶煤矸石∶土壤为30%∶10%∶10%∶50%)、D2处理(污泥∶粉煤灰∶煤矸石∶土壤为30%∶10%∶30%∶30%)和D3处理(污泥∶粉煤灰∶煤矸石∶土壤为30%∶10%∶50%∶10%),以土壤为对照播种柠条、紫穗槐和二色胡枝子。结果表明D1、D2和D3处理重金属含量符合"土壤环境质量标准",可以安全应用于植物栽培上。D1、D2和D3处理促进了紫穗槐和二色胡枝子幼苗生长,抑制柠条幼苗生长。其中D3基质可以为植株生长提供较为充足的养分,D3基质中紫穗槐幼苗株高29.12cm,地径3.73cm,二色胡枝子幼苗株高23.9cm,地径2.37cm。     

煤矸石主要物理特性及在栽培基质中应用的可行性分析

针对煤矿区煤矸石堆积,污染环境,堵塞河道,易造成地质安全等问题,谋求将煤矸石用于栽培基质的主要物料和低产土壤的改良剂。基于煤矸石在栽培基质中应用的可行性为主要研究目标,分别以采自陕西彬县、神木煤矸石为材料,研究了煤矸石的比重、斥水特性及改良措施与效果,结果表明:彬县和神木两地的煤矸石比重分别为1.89 g·cm^-3和2.06 g·cm^-3;神木煤矸石具有轻微斥水性,掺混6.31%以上的农田耕层土壤就能达到消除斥水性的目的;而彬县煤矸石具有严重斥水性,需用0.2%的湿润剂溶液喷洒煤矸石,就能达到消除斥水性的障碍,且效果较为持久。由此得出结论是,就煤矸石的物理性状而言,尽管存在着不同的斥水性障碍,但通过一定的改良,就可具备在栽培基质中使用的可行性。     

煤矸石充填型重构土壤中重金属的生物迁移及分布特征

为了研究不同类型煤矸石充填型重构土壤中重金属的生物迁移及分布特征,以淮北芦岭矿细矸、粗矸和洗矸3种煤矸石及其复垦地玉米(Zea mays L.)为研究对象,测定了其Cu、Pb、Zn、Sn、Hg、Cd、Cr等重金属元素含量,分析了重金属元素在煤矸石和玉米不同器官中的分布特征。结果表明,复垦所用煤矸石重金属含量整体呈洗矸细矸粗矸;复垦地玉米不同器官对重金属元素的富集能力差异较大,果实富集能力弱于其他器官,叶对Cu、Pb、Zn和Cd等重金属元素的富集能力较强。此外,各器官重金属含量与煤矸石中重金属含量之间存在不同程度的相关性。     

A STUDY ON THE STEEL PROTECTION PROPERTY OF GANGUE CONCRETE

In this paper,the effects of quality of gangue amount ofCaO added and w/c ratio upon the weight loss rate and potential of steelas well as pH value and structure of concrete cover of gangue concreteare analysed by means of mercury intrusion porosimetry,scanning electronmicroscopy,pH value measurement and soak-dry cycling.The results ofthis study confirm that the gangue concrete with appropriate proportiongives a good protection for steel.     

高寒矿区人工种草对露天排土场渣山表层基质的影响

露天煤矿开采引起了祁连山区高寒湿地生态环境的部分破坏,本文通过调查7个矿区植被恢复状况,研究了青海木里煤田矿区人工种草对排土场渣山表层基质理化性质的影响,为高寒矿区植被复绿提供参考。结果表明：人工种草可以有效改善排土场渣山表层基质含水量,增加土壤微生物的数量,影响排土场渣山表层基质有机质含量。种草区域细菌、真菌、放线菌平均数量分别是不种草区域的4.20,4.05和2.29倍。7个矿区排土场渣山表层基质速效氮分布极不均衡,差异显著（P<0.05）,种草区域明显高于非种草区域。人工种草后绝大多数矿区全氮、速效磷和速效钾含量明显增加,全钾含量降低。除汞元素外,种草对其它7种重金属（砷、铬、镉、铜、铅、镍、锌）含量产生不同程度的影响,7个矿区砷含量平均值从4.61 mg·kg^-1增加到6.06 mg·kg^-1。     

煤矸石场植被自然恢复初期草本植物生物量研究

以山西潞安矿业集团司马煤业有限公司煤矸石场为对象,采用空间序列代替时间序列的方法对植被自然恢复初期3年的草本植物生物量进行了分析。结果表明,1)各群落生物量之间存在显著差异(P<0.05),草本植物群落总生物量和总地下生物量变化呈现出先增后减的趋势,总地上生物量呈递减趋势。群落地下与地上生物量之比呈明显的上升趋势;2)群落总盖度、平均高度与群落生物量之间无显著相关性。群落物种组成相似性越小,生物量差异越显著。多年生植物地下生物量与总生物量呈显著正相关(P<0.05),而一年生植物的地上、地下和总生物量彼此间相关性不显著;3)依据综合优势比的大小,确定一年恢复期的优势种为野艾蒿,二年恢复期的为北京隐子草、羊草,三年恢复期的为羊草,而自然草地的优势种为阿尔泰狗娃花、羊草。优势种羊草的总生物量逐年增加,地上生物量与地下生物量呈彼此消长的关系。羊草在提高群落生产力以及加快复垦区植被恢复进程中起着重要作用。蒿类植物无论优势种野艾蒿还是伴生种黄花蒿,较大的平均盖度和平均高度会抑制其生物量的积累。     

Biology Migration and Distribution Characteristics of Trace Elements in Reconstructed Soil with Coal Gangue Filling

With mixed gangue,coarse gangue and washed gangue as well as the maize in the reclaimed land in Luling Mine of Huaibei as the research object,the biology migration and distribution characteristics of trace elements in the reconstructed soil with different types of coal gangue filling were studied,the contents of Cu,Pb,Zn,Sn,Hg,Cd and Cr were determined,and the distribution characteristics of the trace elements in the coal gangue and different organs of the maize were analyzed.The results showed that the contents of trace elements were the highest in washed gangue and the least in coarse gangue in the gangue used for the reclamation,and there were significant differences in the enrichment ability of trace elements in different organs of maizes that were planted in reclamation land,of which fruit was weaker than other organs,while leaf presented strong absorption ability.