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81.
广东大宝山矿区土壤重金属含量及其影响因素   总被引:4,自引:0,他引:4  
对大宝山矿区6个功能区进行土壤基本性质分析和重金属含量测定,并分析其相关性。结果显示,土壤Cu,Zn,Pb,Cr含量以露采区最高,土壤Mn和Cd含量以尾矿库最高,大部分区域土壤重金属含量高于国家三级标准,各区域土壤重金属含量变异性较大,与区域功能和土壤来源有关。Cu,Pb,Zn含量之间具有较强相关性,且这三种重金属都与沙粒含量呈正相关,说明可能是由于人为活动释放到土壤中,有机质与Cu、pH、速效钾,粉粒与Mn,CEC与Cr、速效钾,pH与Cr呈正相关;全氮、pH与Cu,碱性氮与Mn,有机质与Cr,全磷、全氮、pH与Cr呈负相关。  相似文献   
82.
大红山铁矿林草植被水土保持效益的研究   总被引:2,自引:0,他引:2  
以裸地为对照,分别对土壤物理性状及土壤的渗透性,土壤中含水量的动态变化,地表径流及土壤流失量等进行了定点定量观测。研究结果表明,林地与草地能有效改善土壤物理性状、增强土壤渗透性和降低土壤水分含量;能通过提高土壤抗蚀性、改善土壤养分含量来充分发挥水土保持效益。研究结果还表明,林地和草地减少侵蚀效益较好,裸地的土壤流失最严重。与裸地相比,林地和草地对地表径流的控制率达到63%~89%,对土壤流失的控制率达到69%~94%。  相似文献   
83.
Brown-coal opencast mining provides a virgin soil substratum at a scale of square kilometres that is open to primary succession. Focusing on this process, we investigated changes in collembolan species composition in a long-term study that lasted almost 40 years (1960–1998) at mine sites, afforested with deciduous trees. The geological overburden, which characterises the soil quality, consisted mainly of Pleistocene and Tertiary sands, interspersed with lignite and dark Tertiary loam and clay.

According to their appearance during the primary succession, we established eight colonising groups, representing 90 of 113 species found. Results from soil samples as well as from pitfall traps were taken into account for the definition of the groups. Thus, edaphic and epedaphic life forms were equally regarded. Generally, “initial”, “pioneer” and “woodland” groups were discernible.

Largest changes in species composition occurred during the first ten years, as indicated by decreasing species turnover rates and increasing alpha diversity. A comparison with other (essentially shorter) studies on Collembola of mine sites (12 in Europe, 3 in other parts of the world) showed that some pioneer species are cosmopolitan whilst others seem to be regionally specific. Important events in the ecosystem development of mine sites, as indicated by the collembolan community, are the first occurrence of other humiphagous soil animal groups, especially that of earthworms, followed by a disappearance of the ectohumus layer. The similarity between collembolan communities of mine sites and of adjacent native woodlands is greatest ten years after afforestation. Fifty years after afforestation, the collembolan community still differed markedly from that of native stands. Thus, a gradual development of the mine site collembolan communities to a comparable native woodland community is not evident from the data.  相似文献   

84.
晋陕蒙接壤区露天矿层状土壤水分入渗特征与模拟   总被引:4,自引:0,他引:4  
分析4种不同结构层状土水分入渗规律,为晋陕蒙接壤区露天矿排土场建设筛选合适的层状土体。设置沙土、砒砂岩、黄绵土和红黏土4种均质土柱以及黄-沙-红、黄-红-沙、沙-黄-砒、黄-砒-沙4种层状土,借助室内土柱自动观测系统测定矿区土壤的入渗过程,通过入渗速率、累积入渗量、湿润锋运移、剖面含水量变化分析不同结构层状土入渗特征,结合晋陕蒙接壤区自然条件,评价适合排土场建设的层状土体。结果表明:黄-沙-红、沙-黄-砒型层状土在短时间内能储存大量水分,且第三层土体阻水作用强,黄-沙-红型层状土下层红黏土阻水效果尤其显著,这两种层状土体是矿区排土场较理想的新土体结构。但是,黄-红-沙型层状土入渗速率慢,在强降雨条件下不能使水分迅速入渗。黄-砒-沙型层状土湿润锋到达第三层土体后运移速率仍很快,阻水效果差,水分容易渗漏到深层土壤,这两种层状土结构不宜应用到晋陕蒙矿区排土场建设中。最后探讨了HYDRUS-1D对入渗过程的模拟,利用均质土剖面含水量反演土壤水力参数模拟4种层状土的入渗过程,得到较好的模拟效果。本文对4种层状土入渗特征的测定与模拟,对于指导露天矿区排土场新土体构筑有一定的理论和现实意义。  相似文献   
85.
Summary We assessed vesicular-arbuscular mycorrhizal (VAM) fungi in coal, lignite, and calcite mine spoils. The level of VAM fungal infection and the population of VAM species in plants on the coal-waste sites were similar to those in plants on the calcite mine spoil. The plants on the coal-waste sites and their associated VAM fungi included Tephrosia purpurea (L.) Pers. with Glomus heterosporum and Sclerocystis microcarpus and Euphorbia hirta L. with G. botryoides and G. ambisporum. The recently revegetated lignite mine spoil supported Eragrostis sp. with G. globiferum, while the oldest revegetated lignite mine spoil supported Cocos nucifera L. with Scutellospora aurigloba and G. aggregatum, and Albizia lebbeck (L.) Benth. with Scutellospora dipapillosa and G. tenue. In the calcite mine spoil, roots of Mukia maderaspatana (L.) M. Romer with Sclerocystis sinuosa, G. dimorphicum, G. heterosporum and G. ambisporum and Datura metal L. with G. pustulatum and G. pulvinatum were found. The level of VAM infection and the population of VAM species in the oldest revegetated site (lignite mine spoil) were comparable with those in the coal-waste and calcite mine-spoil sites.  相似文献   
86.
We studied the behavior of the trace elements (TE) As, Cu, Pb and Zn associated with sulphide minerals in tailings of different age at the Guanajuato mining district, Mexico. The objective was to determine the dominant fractions into which the TE move as tailings age and to identify how much time is needed until the dominant metal fractions approach equilibrium. We collected 21 samples from the surface of mine waste deposits of different ages (0, 2 , 4, 16, 70, 75, and 100 years), and measured their aqua regia extractable contents of As, Cu, Pb and Zn. We also applied a sequential extraction procedure to quantify water soluble TE as well as TE associated with carbonates, iron oxides, sulphides and the residual fraction. The mineralogy was analysed by X-ray diffraction, and selected samples were studied on polished specimens through a stereoscopic microscope. The TE in samples extracted with aqua regia ranged between 10 and 168 mg kg− 1 for As, 12 to 194 mg kg− 1 for Cu, 31 to 308 mg kg− 1 for Pb, and 122 to 1129 mg kg− 1 for Zn, and varied in a wide range within each age group of tailings. Water soluble Cu, Pb and Zn contents were below detection limits in almost all samples, which was attributed to the alkaline pH (7.17 to 8.61) in the tailings. Water extractable As was detected only in tailings older than 16 years, and concentrations ranged between 0.06 and 7.58 mg kg− 1. The proportion of TE associated with sulphides decreased in the tailings as they age, while the proportion of TE associated with iron oxides increased with time of exposure to the atmosphere, approximating equilibrium after 60 years for As, Cu and Zn, and after 40 years for Pb. Observations of polished specimens suggests that oxidation proceeds until coatings of secondary minerals cover and protect sulphide mineral grains from further weathering. First order rate equations were adjusted to the proportions of TE associated with either sulphides or iron oxides. Assuming that the TE in sulphide fractions correspond to arsenopyrite (FeAsS), chalcopyrite (CuFeS2), galena (PbS) and sphalerite (ZnS), the relative oxidation rate of sulphides followed the order: PbS > ZnS > FeAsS ≈ CuFeS2, while the relative affinity of the elements with iron oxides followed the sequence Cu ≈ Zn > As > Pb.  相似文献   
87.
重庆市经历几十年的矿产资源开发,严重的矿山环境问题和诱发日益频繁的次生地质灾害,已经影响到区域社会和经济的发展。该文概述了重庆市矿山环境治理现状及存在的主要问题,探讨了矿山地质环境治理的对策和建议,并提出具体防治措施。  相似文献   
88.
采用WEB与数据仓库技术,从系统设计原则与设计目标、系统总体结构、系统部署、数据仓库设计与系统功能等方面,设计与实现了福建名木古树智能管理系统。该系统建立了一个B/S架构的服务器数据仓库,将数据挖掘与OLAP思想相结合,为不同层次的管理者提供智能决策信息。  相似文献   
89.
为揭示煤矿复垦区土壤氮素内循环中的矿化及硝化特征,探索不同复垦模式与不同复垦年限下复垦土壤的氮素转化效率,采集山西安太堡露天煤矿中复垦3年、9年、21年苜蓿地及3年荞麦地表层(0~20 cm)土壤,并以3年自然恢复和未复垦新排土为对照,采用间歇淋洗好气培养法与恒温培养法研究各采样地土壤矿化与硝化过程,利用一级反应动力学模型与Logistic方程对有机氮素的矿化与硝化数据进行拟合。结果表明,3年苜蓿地的矿化速率最高,21年苜蓿地的矿化速率最低,且土壤氮素快速矿化主要在培养前7 d,之后逐渐平缓,并在28 d趋于稳定。经一级动力学方程拟合可知,氮矿化势(No)的变化范围为89.28~124.51 mg·kg-1,21年苜蓿地 > 3年自然恢复地 > 3年苜蓿地 > 3年荞麦地 > 未复垦新排土 > 9年苜蓿地;矿化速率常数(k)的变化范围为0.022 6~0.051 9,3年苜蓿地 > 9年苜蓿地 > 未复垦新排土 > 3年自然恢复地 > 3年荞麦地 > 21年苜蓿地。氮矿化势与土壤有机质含量显著正相关(r=0.91)。复垦区各土壤随培养时间的延长硝态氮含量大致为"S"型曲线且可分为3个阶段:前期阶段(0~5 d)-上升阶段(5~14 d)-稳定阶段(14~28 d);Logistic方程拟合结果显示:复垦年限显著影响硝化高峰出现的时间(不同复垦年限苜蓿地最大相差6.85 d),21年苜蓿地硝化过程剧烈而短促,3年自然恢复地的硝化过程缓慢而漫长;耕地较草地有更大的硝化速率与更长的硝化时间。长期的种植苜蓿复垦显著提高了土壤的氮库容量,矿化过程更为平稳。  相似文献   
90.
Carbon (C) accreditation of forest development projects is one approach for sequestering atmospheric CO2, under the provisions of the Kyoto protocol. The C sequestration potential of reforested mined land is not well known. The purpose of this work was to estimate and compare the ecosystem C content in forests established on surface, coal-mined and non-mined land. We used existing tree, litter, and soil C data for fourteen mined and eight adjacent, non-mined forests in the Midwestern and Appalachian coalfields to determine the C sequestration potential of mined land reclaimed prior to the passage of the Surface Mining Control and Reclamation Act (1977). We developed statistically significant and biologically reasonable models for ecosystem C across the spectrum of site quality and stand age. On average, the highest amount of ecosystem C on mined land was sequestered in pine stands (148 Mg ha−1), followed by hardwood (130 Mg ha−1) and mixed stands (118 Mg ha−1). Non-mined hardwood stands sequestered 210 Mg C ha−1, which was about 62% higher than the average of all mined stands. Our mined land response surface models of C sequestration as a function of site quality and age explained 59, 39, and 36% of the variation of ecosystem C in mixed, pine, and hardwood stands, respectively. In pine and mixed stands, ecosystem C increased exponentially with the increase of site quality, but decreased with age. In mined hardwood stands, ecosystem C increased asymptotically with age, but it was not affected by site quality. At rotation age (60 yr), ecosystem C in mined hardwood stands was less on high quality sites, but similar for low quality sites compared to non-mined hardwood stands. The overall results indicated that the higher the original forest site quality, the less likely C sequestration potential was restored, and the greater the disparity between pre- and post-mining C sequestration stocks.  相似文献   
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