Floristic variation in plant communities on metalliferous mining residues in the northern and southern Pennines,England

Vegetation and soil surveys were conducted on metalliferous mine wastes in the northern and southern Pennines of England. Analyses of vegetation composition in relation to soil chemical variation were performed. Ordination analysis facilitated the detection of groups of co-occurring species which are characteristic of types of metal-contaminated soil. The results of regression analysis implied the importance of soil pH and concentration of available lead or zinc, depending upon region, in determining species distributions. A strong interactive effect was evident between soil phosphorus and zinc content in influencing species distributions in the southern Pennines sample.Regional similarities in the vegetation of apparently similar metalliferous soils existed. The unusually high species richness of some soils was associated with relatively low concentrations of heavy metals. Many species of relatively floristically-rich wastes were also colonists of surrounding grasslands or woodland. This indicated the potential importance of propagule availability and capability for rapid establishment on bare or unstable ground. Mechanisms of physiological stress avoidance, rather than heavy-metai tolerance, may explain the occurrence of non-metallophytes on soils contaminated with lead and zinc.     

锑矿区人发中铋的污染状况

采用氢化物发生-原子荧光光谱法（HG-AFS）,对经过硝酸-高氯酸消解后的锡矿山矿区和贵阳市人体头发样品中重金属铋（Bi）含量进行分析。结果表明,锡矿山矿区和贵阳市人体头发中Bi的检出率分别为95.5%、22.7%,矿区居民人体头发中Bi含量显著高于作为对照的贵阳市居民人体头发中的Bi含量。锡矿山矿区男性和女性居民人发中Bi质量分数范围分别为0.0079～0.1842μg？g-1、0.0080～0.1403μg？g-1,平均值（中位数）分别为0.0480（0.0280）μg？g-1、0.0482（0.0397）μg？g-1,矿区较高的人发Bi含量主要集中在30～49岁的中年人群中。通过独立样本t检验发现,锡矿山矿区男性和女性发样中Bi含量差异不显著（p〉0.05）。研究结果说明锑矿开采和冶炼区域重金属Bi对人体健康的危害明显比非矿区严重。     

Distribution and phytoavailability of antimony at an antimony mining and smelting area,Hunan, China

An investigation of the distribution, fractionation and phytoavailability of antimony (Sb) and other heavy metals in soil sampled at various locations in the vicinity of a Sb mine revealed elevated levels of Sb, most certainly due to the mining activities. The concentration of Sb in the soil samples was 100.6–5045 mg kg⁻¹; in comparison, the maximum permissible concentration for Sb in soil in The Netherlands is 3.5 mg kg⁻¹, and the maximum permissible concentration of pollutant Sb in receiving soils recommended by the World Health Organization is 36 mg kg⁻¹. The soil sampled near the Sb mine areas had also contained high concentrations of As and Hg. Root and leaf samples from plants growing in the Sb mine area contained high concentrations of Sb, with the concentration of Sb in the leaves of radish positively correlating with Sb concentrations in soil. The distribution of Sb in the soil showed the following order: strongly bound to the crystalline matrix > adsorbed on Fe/Mn hydrous oxides, complexed to organic/sulfides, bound to carbonates > weakly bound and soluble. Solvents showed varying levels of effectiveness in extracting Sb (based on concentration) from the soil, with , in decreasing order. The concentration of easily phytoavailable Sb was high and varied from 2.5 to 13.2 mg kg⁻¹, the percentage of moderately phytoavailable Sb ranged from 1.62 to 8.26%, and the not phytoavailable fraction represented 88.2–97.9% of total Sb in soils.     

Stabilization of the As-contaminated soil from the metal mining areas in Korea

Phytoextraction is a remediation technology with a promising application for removing arsenic (As) from soils and waters. Several plant species were evaluated for their As accumulation capacity in hydroponic culture amended with As. Cucumis sativus (cucumber) displayed the highest tolerance against As among 4 plants tested in this study (corn, wheat, sorghum and cucumber). The germination ratio of Cucumis sativus was more than 50% at the high concentration of 5,000 mg-As/l. In Cucumis sativus grown in a solution contaminated with 25 mg-As/l, the accumulated As concentrations in the shoot and root were 675.5 ± 11.5 and 312.0 ± 163.4 mg/kg, respectively, and the corresponding values of the translocation and bioaccumulation factors for As were 1.9 ± 0.9 and 21.1 ± 8.4, respectively. These results indicate Cucumis sativus is to be a candidate plant for phytoextraction of As from soils and water.     

Stabilization of the As-contaminated soil from the metal mining areas in Korea

The stabilization efficiencies of arsenic (As) in contaminated soil were evaluated using various additives such as limestone, steel mill slag, granular ferric hydroxide (GFH), and mine sludge collected from an acid mine drainage treatment system. The soil samples were collected from the Chungyang area, where abandoned Au-Ag mines are located. Toxicity characteristic leaching procedure, synthetic precipitation leaching procedure, sequential extraction analysis, aqua regia digestion, cation exchange capacity, loss on ignition, and particle size distribution were conducted to assess the physical and chemical characteristics of highly arsenic-contaminated soils. The total concentrations of arsenic in the Chungyang area soil ranged up to 145 mg/kg. After the stabilization tests, the removal percentages of dissolved As(III) and As(V) were found to differ from the additives employed. Approximately 80 and 40% of the As(V) and As(III), respectively, were removed with the use of steel mill slag. The addition of limestone had a lesser effect on the removal of arsenic from solution. However, more than 99% of arsenic was removed from solution within 24 h when using GFH and mine sludge, with similar results observed when the contaminated soils were stabilized using GFH and mine sludge. These results suggested that GFH and mine sludge may play a significant role on the arsenic stabilization. Moreover, this result showed that mine sludge can be used as a suitable additive for the stabilization of arsenic.     

Stabilization of the As-contaminated soil from the metal mining areas in Korea

The stabilization efficiencies of arsenic (As) in contaminated soil were evaluated using various additives such as limestone, steel mill slag, granular ferric hydroxide (GFH), and mine sludge collected from an acid mine drainage treatment system. The soil samples were collected from the Chungyang area, where abandoned Au–Ag mines are located. Toxicity characteristic leaching procedure, synthetic precipitation leaching procedure, sequential extraction analysis, aqua regia digestion, cation exchange capacity, loss on ignition, and particle size distribution were conducted to assess the physical and chemical characteristics of highly arsenic-contaminated soils. The total concentrations of arsenic in the Chungyang area soil ranged up to 145 mg/kg. After the stabilization tests, the removal percentages of dissolved As(III) and As(V) were found to differ from the additives employed. Approximately 80 and 40% of the As(V) and As(III), respectively, were removed with the use of steel mill slag. The addition of limestone had a lesser effect on the removal of arsenic from solution. However, more than 99% of arsenic was removed from solution within 24 h when using GFH and mine sludge, with similar results observed when the contaminated soils were stabilized using GFH and mine sludge. These results suggested that GFH and mine sludge may play a significant role on the arsenic stabilization. Moreover, this result showed that mine sludge can be used as a suitable additive for the stabilization of arsenic.     

Radon in soil gas and its relationship with some major faults of SW England

The south-west of England was designated by the National Radiological Protection Board (NRPB) as the first ‘Radon Affected Area’, as over 1% of the housing stock is estimated to have an indoor radon concentration in excess of the 200 Bq m⁻³ Action Level. The situation is even worse for houses situated above uraniferous granite intrusions, where over 30% are thought to be above the Action Level. The aim of this study is to investigate the relationship between the level of radon in soil gas and the local geology. Particularly high radon levels were measured along major fault zones. This could be explained by: increased rate of migration of the radon due to the permeable fault, the presence of radium or radon-bearing ground water within the fault, or secondary uranium mineralisation. Seasonal variations are also considered.     

Antimony speciation and contamination of waters in the Xikuangshan antimony mining and smelting area,China

Water samples from Xikuangshan (China), the world largest antimony (Sb) mine with a Sb mining and smelting history of more than 200 years, were analyzed. These water samples ranged from stream water in the vicinity of the mining and smelting area that received seepage from ore residues to the underground mine-pit drainage. The concentrations of total Sb, Sb (III) and Sb (V) of the samples were determined by HPLC-ICP-MS. In addition, water pH and concentrations of major cations and anions were analyzed. All 18 samples demonstrated total Sb concentrations with ppm levels from 0.33 ppm to 11.4 ppm, which is two to three orders of magnitude higher compared to the typical concentration of dissolved Sb in unpolluted rivers (less than 1 ppb). This is probably the first time that such high Sb contents have been documented with complete environmental information. Distribution of total Sb and Sb species was investigated, taking into account the respective local environment (in the mining area or close to the smelter, etc.). Sb (V) was the predominant valence in all 18 samples. Only trace levels of Sb (III) were detected in 4 of the 18 samples. Geochemical speciation modeling showed the dominant species was Sb(OH)₆⁻. It is also probably the first time that such high Sb contents have been documented in the natural environment with Sb speciation distribution information. Several potential oxidation pathways are also discussed that might have facilitated the oxidation of Sb (III) in the natural environment. Signs of intoxication were observed among local mine workers with extensive exposure to different forms of Sb for a long period of time.     

Arsenic contamination in water,soil, sediment and rice of central India

Arsenic contamination in the environment (i.e. surface, well and tube-well water, soil, sediment and rice samples) of central India (i.e. Ambagarh Chauki, Chhattisgarh) is reported. The concentration of the total arsenic in the samples i.e. water (n=64), soil (n=30), sediment (n=27) and rice grain (n=10) were ranged from 15 to 825 μg L⁻¹, 9 to 390 mg kg⁻¹, 19 to 489 mg kg⁻¹ and 0.018 to 0.446 mg kg⁻¹, respectively. In all type of waters, the arsenic levels exceeded the permissible limit, 10 μg L⁻¹. The most toxic and mobile inorganic species i.e. As(III) and As(V) are predominantly present in water of this region. The soils have relatively higher contents of arsenic and other elements i.e. Mg, Al, Si, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Ga, Zr, Sn, Sb, Pb and U. The mean arsenic contents in soil of this region are much higher than in arsenic soil of West Bengal and Bangladesh. The lowest level of arsenic in the soil of this region is 3.7 mg kg⁻¹ with median value of 9.5 mg kg⁻¹. The arsenic contents in the sediments are at least 2-folds higher than in the soil. The sources of arsenic contamination in the soil of this region are expected from the rock weathering as well as the atmospheric deposition. The environmental samples i.e. water, soil dust, food, etc. are expected the major exposure for the arsenic contamination. The most of people living in this region are suffering with arsenic borne diseases (i.e. melanosis, keratosis, skin cancer, etc.).     

Arsenic in garden soils and vegetable crops in Cornwall,England: Implications for human health

Total concentrations of arsenic in surface (0–15cm) garden soils in the historical mining area of Hayle-Camborne-Godolphin, Cornwall, England are large and range widely (144–892 g/g). Amounts of water soluble and acid-fluoride extractable soil arsenic are significantly correlated with total content.Examination of 6 salad and vegetable crops grown in 32 gardens has shown arsenic concentrations in the edible tissues to be only slightly elevated. There were strong correlations between arsenic in beetroot, lettuce, onion and peas and soil arsenic (total, water soluble and acid extractable). Regression equations have been calculated. Ridge regression analysis applied to test the importance of other soil variables has shown both iron and phosphorus to influence the uptake of arsenic.Arsenic in all the vegetables sampled was below the statutory limit in the U.K. of 1 mg/kg fresh weight. Implications for health should be assessed in relation to other exposure routesvia water, air and directly ingested dust and soil.     

Arsenic,antimony, and other trace element contamination in a mine tailings affected area and uptake by tolerant plant species

The study was conducted to characterize mineralogical and elemental composition of mine tailings in order to evaluate the environmental hazards, and identify the metal accumulation potential of native plant species from São Domingos mine, one of the long-term activity mines of the Iberian Pyrite Belt dating back to pre-Roman times. The mine tailings including soils and different plant species from São Domingos were analyzed for determination of tailings characteristics and chemical element contents in tailings and plants. The large amounts of mining wastes are causing significant adverse environment impacts due to acid mine drainage production and mobilization of potentially toxic metals and metalloids in residential areas, agricultural fields, downstreams, and rivers. The typical mineralogical composition is as follows: quartz, micas, K-feldspar, olivine-group minerals, magnetite, goethite, hematite, jarosite, and sulfides. The mine tailings were highly contaminated by As, Ag, Cr, Hg, Sn, Sb, Fe, and Zn; and among them, As and Sb, main contaminants, attained the highest concentrations except Fe. Arsenic has exhibited very good correlations with Au, Fe, Sb, Se, and W; and Sb with As, Au, Fe, Se, Sn, and W in tailings. Among the all plant species, the higher concentrations of all the metals were noted in Erica andevalensis, Erica australis, Echium plantagium, and Lavandula luisierra. Considering the tolerant behavior and abundant growth, the plant species Erica australis, Erica andevalensis, Lavandula luisierra, Daphne gnidium, Rumex induratus, Ulex eriocladus, Juncus, and Genista hirsutus are of major importance for the rehabilitation and recovery of degraded São Domingos mining area.     

The agricultural impact of opencast coal mining in England and Wales

Opencast coal mining in England and Wales can cause a wide range of environmental problems which are increasingly public issues due to the planned expansion in output and the impact this may have on agriculture and landscape. Opencast mining is reviewed on a county by county basis to identify the variations in the disturbance caused. A detailed review of restoration techniques and the agricultural quality of the restored land is presented, and the role of Planning Authorities is discussed. Significant variations in the impact of opencast operations are identified, especially in relation to the potential for derelict land reclamation and the grade of agricultural land affected. The latter is generally lower grade 3 and below, although in certain areas operations are entering land of higher agricultural and scenic quality. The quality of restoration, while good, still has scope for improvements, such as reducing soil compaction and the subsequent management of the land by the farmer. The impact on agricultural productivity is difficult to assess, but it appears to be only slight in those cases where recent restoration techniques were used and when lower grade agricultural land is taken.     

改良剂对土壤Sb赋存形态和生物可给性的影响

采用室内土壤培养法研究不同改良剂(骨炭、生物调理剂、沸石、石灰、油菜秸秆、生物炭、堆肥和赤泥)对土壤Sb化学形态转化和生物可给性的影响.结果表明,除堆肥处理外,添加5%的其他7种改良剂均显著地提高了土壤的p H值,其中石灰处理p H最为明显.BCR分级提取表明,土壤Sb主要以残渣态形式存在.添加生石灰、骨炭和生物调理剂显著地提高了土壤Sb的移动性,而添加赤泥、生物炭和堆肥却显著地降低了土壤Sb的移动性.添加不同的改良剂对土壤Sb的生物可给性也有影响,但是受不同培养时间影响较大.培养2个月后,添加5%的堆肥、5%赤泥和5%生物炭处理导致土壤Sb的生物可给性含量分别比对照降低38%、23%和20%;而添加5%的石灰、5%油菜秸秆和5%的生物调理剂处理导致土壤Sb的生物可给性含量分别比对照提高1.07倍、1.06倍和1.11倍.堆肥、赤泥和生物炭是钝化Sb污染土壤的潜力材料.     

Some effects of century old abandoned lead mining operations on streams in Missouri,USA

Lead has been mined in the Old Lead Belt region of southeastern Missouri, USA since the early 1700s. Mining operations ceased totally in 1972. Since no other major industries were associated with the region, an investigation was initiated to study the long-term environmental effects of lead mining activities on the water quality sediments and biota otarea receiving streams. The principal study area was Flat River Creek,. which drained the major mining operations of the region. The findings of this study indicated the water of the lower Flat River Creek below the mining elevation contained elevated levels of lead, zinc, calcium and magnesium. The sediments and biota of the same stream area were also found to contain significantly higher levels of lead and zinc as well as copper and cadmium. Algae, crayfish and minnows were all found to have concentrated these metals. The studies indicated that some type of abandonment plan must be developed for the control and treatment of heavy metal pollution for mining operations on a continuing basis.     

水、土环境中锑污染与控制研究进展

随着工业的发展,锑作为一种具有潜在毒性和致癌性的类金属元素,已经较为广泛地存在于水体和土壤环境中,显现出不可忽视的环境问题,并引起国际科学界的高度关注。文章综述了锑在水体和土壤环境中的污染现状、化学行为形态以及污染控制方面的研究进展。由采矿业、制造业带来的锑水土污染问题较为突出,目前的处理处置方法难以满足需求。今后需要在锑的水土环境化学方面加强研究,探讨锑的迁移转化规律;高效吸附材料的开发制备也是一个重要内容;植物组合修复土壤中的锑污染将是一个重要的突破口。     

水、土环境中锑污染与控制研究进展

随着工业的发展,锑作为一种具有潜在毒性和致癌性的类金属元素,已经较为广泛地存在于水体和土壤环境中,显现出不可忽视的环境问题,并引起国际科学界的高度关注。文章综述了锑在水体和土壤环境中的污染现状、化学行为形态以及污染控制方面的研究进展。由采矿业、制造业带来的锑水土污染问题较为突出,目前的处理处置方法难以满足需求。今后需要在锑的水土环境化学方面加强研究,探讨锑的迁移转化规律;高效吸附材料的开发制备也是一个重要内容;植物组合修复土壤中的锑污染将是一个重要的突破口。     

Heavy metals in soils in north Somerset,England, with special reference to contamination from base metal mining in the Mendips

A 2 × 2 km grid survey of surface soils was conducted over 600 km of North Somerset, England, to investigate the role of pollution from former base metai mines on soil heavy metal content. Soil contents of Pb, Zn, Cu and Cd were determined by atomic absorption spectrometry after extraction in hot, concentrated nitric acid. Most of the soils were contaminated by lead, zinc and cadmium. Isoline maps and perspective block diagrams showed this contamination to be most severe on the Mendip plateau, especially in the vicinity of Shipham, Wells and Priddy districts. Resurgences, polluted from mine drainage, also contaminated soils at the base of the Mendip slopes and, over the lowlands, trace element enriched Liassic shales caused significant local anomalies.     

Arsenic mobility in the amended mine tailings and its impact on soil enzyme activity

The objectives of this study were to elucidate the effects of soil amendments [Ferrous sulfate (Fe^II), red mud, Fe^II with calcium carbonate (Fe^II/L) or red mud (RM/F), zero-valent iron (ZVI), furnace slag, spent mushroom waste and by-product fertilizer] on arsenic (As) stabilization and to establish relationships between soil properties, As fractions and soil enzyme activities in amended As-rich gold mine tailings (Kangwon and Keumkey). Following the application of amendments, a sequential extraction test and evaluation of the soil enzyme activities (dehydrogenase and β-glucosidase) were conducted. Weak and negative relationships were observed between water-soluble As fractions (As_WS) and oxalate extractable iron, while As_WS was mainly affected by dissolved organic carbon in alkaline tailings sample (Kangwon) and by soil pH in acidic tailings sample (Keumkey). The soil enzyme activities in both tailings were mainly associated with As_WS. Principal component and multiple regression analyses confirmed that As_WS was the most important factor to soil enzyme activities. However, with some of the treatments in Keumkey, contrary results were observed due to increased water-soluble heavy metals and carbon sources. In conclusion, our results suggest that to simultaneously achieve decreased As_WS and increased soil enzyme activities, Kangwon tailings should be amended with Fe^II, Fe^II/L or ZVI, while only ZVI or RM/F would be suitable for Keumkey tailings. Despite the limitations of specific soil samples, this result can be expected to provide useful information on developing a successful remediation strategy of As-contaminated soils.