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1.
Taosha Ou Mengyun Guan Yongrui Mai Peiyan Deng Yutang Xiao Dayi Deng 《Journal of Soils and Sediments》2017,17(8):2202-2213
Purpose
Surface sediments contaminated with high levels of multiple heavy metal(loid) species are very common environmental problems. Especially, the labile and bioaccessible fractions of heavy metal(loid)s in the sediments are posing serious risks to the biota and the overlaying water quality. This study aimed at developing a potential method to manage the activity of the labile fractions of heavy metal(loid)s in surface sediments.Materials and methods
This study assessed the feasibility of adding iron powder, a low-cost industrial by-product, to sediments containing high levels of Pb, As, and Cd to adsorb labile fractions of heavy metal(loid)s onto the sorbent surfaces and to retrieve the heavy metal(loid) laden powders by applying external magnetic field. In addition, the redistribution of Pb, Cd, and As in different sediment fractions, the dissolved fraction and the sorbent-adsorbed fraction, was also investigated and characterized.Results and discussion
The results indicate that the bioactive labile fractions (exchangeable and carbonate-bound fractions) of heavy metal(loid)s are prone to concentrating onto iron powders and can be selectively removed from the sediments by magnetic retrieval. In addition, iron addition induces conversion of labile fractions of heavy metal(loid)s into more stabilized fractions.Conclusions
Overall, the process can effectively minimize the activity of labile fractions of heavy metal(loid)s in surface sediments.2.
Fulvio Onorati Cristian Mugnai Marina Pulcini Massimo Gabellini 《Journal of Soils and Sediments》2013,13(2):474-487
Purpose
In order to assess sediment quality and to account for the great geochemical heterogeneity of Italian coasts, Local Sediment Quality Guidelines (LSQGs) have to be defined for specific portions of the coastline based on the approach developed by ICRAM–APAT (2007). This paper describes the application of LSQGs to the harbour of Fiumicino (Rome, Italy). The aims were to evaluate the quality of dredging sediments through an integrated chemical–ecotoxicological approach and to define suitable management options.Materials and methods
Thirty-eight sediment cores, covering the planned dredging depth, were collected in the study area and sliced into 92 sediment samples. Chemical analyses, including inorganic and organic contaminants as well as microbiological parameters, were carried out for all the samples. A bioassay battery composed by the bacterium Vibrio fischeri, the sea urchin Paracentrotus lividus and the alga Dunaliella tertiolecta was applied on one third of the samples. LSQGs were derived from chemical and ecotoxicological data of the harbour area, and were integrated with those from the identified dumping site. The Baseline Chemical Level, corresponding to an absent or unlikely ecotoxicological hazard, and the Limit Chemical Level, corresponding to a probable ecotoxicological hazard, were the LSQGs derived for each chemical.Results and discussion
A gradient of increasing contamination, moving inland due to urban and agricultural effluents, was observed. Ecotoxicological analyses, similar to microbiological ones, confirmed the poor sediment quality, with the exception of a sample located at the port entrance, where hydrodynamics flush sediment away from the site. Principal component analysis allowed a clear discrimination of three areas, each affected by a different contamination degree and influenced by many sources related to industrial, commercial and/or urban activities. Using LSQGs and the results of bioassays, it was possible to classify the sediment quality of the whole harbour area and to define the most suitable management options. It was found that Fiumicino harbour sediment was not suitable for either beach nourishment or for offshore dumping, with the exception of a negligible amount located at the port entrance. In turn, most sediment seemed to be suitable for disposal in a properly sealed confined disposal facility or for mechanical/chemical treatment.Conclusions
This case study provided useful insights for implementing the development of LSQGs for more realistic sediment management and will assist in promoting its application to harbour dredging at the local level. 相似文献3.
Sandro R. Urban Albertina X. R. Corrêa Carlos A. F. Schettini Paulo R. Schwingel Rafael M. Sperb Claudemir M. Radetski 《Journal of Soils and Sediments》2010,10(1):65-76
Purpose
Most of the information concerning the effects of contaminated sediments on estuarine organisms deals with the impacts of bed forming sediments. The ecotoxicological potential at the time of a dredging operation is more difficult to assess, and few studies have dealt specifically with resuspended contaminated sediments. The aim of this study was to determine whether release of contaminants through sediment resuspension during a dredging operation in the Itajaí-açu estuary (Brazil) changed the water quality classification and had an ecotoxicological impact on the near-field water column during the critical moment of this operation.Materials and methods
Waters from two sites (control and dredged sites) were analyzed for physicochemical parameters before, during, and after a dredging operation. In parallel, a short-term, sensitive battery of biotests (bacteria, algae, and daphnids) was performed with water samples before and during this operation according to the ISO bioassay protocols.Results and discussion
No short-term toxicity was observed with waters collected before or during the dredging operation. The results showed that desorption of contaminants from suspended particles of sediments with a low level of contamination during a dredging operation lowered the water quality in the near-field water column but that this did not promote significant acute toxicity effects on the organisms tested.Conclusions
More detailed studies are needed (e.g., the question of the reliability of biotests under turbulent, particle-rich conditions) to fully understand this complex issue regarding water column ecotoxicity during the whole dredging operation and to support decisions on the management of dredging activities.4.
Adriana Alves Pereira Bert van Hattum Abraham Brouwer Peter Michiel van Bodegom Carlos Eduardo Rezende Wim Salomons 《Journal of Soils and Sediments》2008,8(4):239-252
Background, aim, and scope
In water systems, water quality and geochemical properties of sediments determine the speciation of trace metals, metal transport, and sediment–water exchange, influencing metal availability and its potential effects on biota. Studies from temperate climates have shown that iron-ore mining and tailing wastewaters, besides being a source of trace metals, usually show high levels of dissolved ions and particulate suspended matter, thus having the potential of indirectly changing metal bioavailability. For the first time in the tropics, we identified the effects of iron-ore mining and processing on metal bioavailability in a coastal lagoon. With an extensive sampling scheme, we investigated the potential sources of metals; the links among metal levels in water, sediments, and invertebrates; and the contrasting effects on metal speciation and bioavailability.Methodology
The metals Fe, Mn, Al, Cr, Zn, Cu, Ni, Pb, Cd, Hg, and As were measured in water, sediments (surface and profiles), and invertebrates from Mãe-Bá Lagoon and in the sites directly influenced by the mining operations (tailing dams and nearby rivers). In addition, samples from two other lagoons, considered pristine, were analyzed. The study area is located in the southeast of Brazil (Iron Quadrangle Region and a coastal area of Espírito Santo State). General water characteristics included pH, dissolved organic carbon, alkalinity, and anion composition. Water metal speciation was assessed by a speciation model (Chemical Equilibria in Aquatic Systems). Grain-size distribution, organic carbon, carbonate, and acid volatile sulfide (AVS) were determined in sediments. Statistical methods included comparison of means by Mann–Whitney test, ordination and correlation analyses, and analysis of regression for geochemical normalization of metals with grain size.Results and discussion
The dissolved metal concentrations, the total metal levels in sediments, and the normalization based on the fine sediment fraction showed that the mining operations constitute potential sources of Fe, Mn, Cr, Cu, Ni, Pb, As, and Hg to Mãe-Bá Lagoon. However, trace metal availability was reduced because of increased pH, hardness, and sulfide content (356 μmol/g) in the sites influenced by the mining. The lagoon showed similar water chemistry as in the mining sites, with metal bioavailability further decreased by the presence of dissolved organic carbon and chloride. Although AVS levels in the lagoon were low (0.48–56 μmol/g), metal bioavailability was reduced because of the presence of organic matter. Metal levels in invertebrates confirmed the predicted low metal bioavailability in Mãe-Bá Lagoon. The lagoon was considered moderately contaminated only by Hg and As.Conclusions
The iron-ore mining and processing studied here constitute potential sources of metal pollution into the tropical lagoon. Contrary to expectations, however, it also contributes to reducing the overall metal bioavailability in the lagoon.Recommendations and perspectives
These findings are believed to be useful for evaluating metal exposure in a more integrated way, identifying not only the sources of pollution but also how they can affect the components involved in metal speciation and bioavailability in water systems, leading to new insights. 相似文献5.
Bin Cui Meilin Zhu Yang Jiang Yanxue Jiang Hongbin Cao 《Journal of Soils and Sediments》2014,14(8):1456-1468
Purpose
Frequent mining activities and higher background values in soil have led to the contamination of the sediments of some rivers in southwest China by several metals and arsenic (As). This study combined multivariate analysis with geochemical approaches to differentiate mining activity from other sources, which may aid to evaluate the effectiveness of reducing mining release.Materials and methods
Sixteen sediment samples were collected along the Yuan River, China. The total concentrations of lead (Pb), zinc (Zn), copper (Cu), cadmium (Cd), chromium (Cr), mercury (Hg), and As were measured by inductively coupled plasma-atomic emission spectrometer (ICP-AES). The Pb isotopic composition was measured using a thermal ionization mass spectrometer (TIMES). Both geochemical approaches and multivariate statistical analysis were used to identify the sources of these metals. The fractionation of Pb was determined through a Community Bureau of Reference (BCR) sequential extraction procedure to aid the identification of the sources.Results and discussion
The concentrations and enrichment factors (EFs) of Pb, Zn, Cu, Cd, and As in the middle reach of the river were higher than those at the other sites, indicating anthropogenic sources. The factor analysis (FA) extracted “mining and smelting,” “mixture of anthropogenic and natural,” and “natural” factors. The Pb isotope composition of metal ores was similar (206Pb/207Pb?<?1.190 and 208Pb/206Pb?>?2.023) to that found in the sediments in the middle reach, indicating anthropogenic sources of mining activities. Compared with the narrow ranges of the δ34S ratios in the bedrock (+8.5 to +9.3?‰) and the metal ores (?1.4 to +1.9?‰), the sediment samples presented a relatively wide range of δ34S ratios from ?2.6 to +9.2?‰ with a mean of +2.6?‰, which suggests a mixed composition. The BCR sequential extraction procedure revealed that the proportion of the extractable fraction in the sediments in the middle reach was higher than that in other sites, suggesting anthropogenic sources as the cause of contamination in the study area.Conclusions
Lead, Zn, Cu, Cd, Cr, Hg, and As are mainly derived from natural materials in the upstream region. In the middle reach, these elements are the result of anthropogenic activities, particularly activities associated with the mining industry. In the downstream region, the origin of these elements is considered to be a mixture of anthropogenic and natural sources. In addition to geochemical approaches and multivariate statistical analysis, the BCR sequential extraction method is an effective procedure for the identification of the anthropogenic sources of sediment-associated metals. 相似文献6.
Barbara Palumbo-Roe Joanna Wragg Vanessa J. Banks 《Journal of Soils and Sediments》2012,12(10):1633-1640
Purpose
Past metal mining has left a legacy of highly contaminated sediments representing a significant diffuse source of contamination to water bodies in the UK and worldwide. This paper presents the results of an integrated approach used to define the role of sediments in contributing to the dissolved lead (Pb) loading to surface water in a mining-impacted catchment.Materials and methods
The Rookhope Burn catchment, northern England, UK is affected by historical mining and processing of lead ore. Quantitative geochemical loading determinations, measurements of interstitial water chemistry from the stream hyporheic zone and inundation tests of bank sediments were carried out.Results and discussion
High concentrations of Pb in the sediments from the catchment, identified from the British Geological Survey Geochemical Baseline Survey of the Environment (GBASE) data, demonstrate both the impact of mineralisation and widespread historical mining. The results from stream water show that the stream Pb load increased in the lower part of the catchment, without any apparent or significant contribution of point sources of Pb to the stream. Relative to surface water, the interstitial water of the hyporheic zone contained high concentrations of dissolved Pb in the lower reaches of the Rookhope Burn catchment, downstream of a former mine washing plant. Concentrations of 56???g?l?1 of dissolved Pb in the interstitial water of the hyporheic zone may be a major cause of the deterioration of fish habitats in the stream and be regarded as a serious risk to the target of good ecological status as defined in the European Water Framework Directive. Inundation tests provide an indication that bank sediments have the potential to contribute dissolved Pb to surface water.Conclusions
The determination of Pb in the interstitial water and in the inundation water, taken with water Pb mass balance and sediment Pb distribution maps at the catchment scale, implicate the contaminated sediments as a large Pb supply to surface water. Assessment of these diffuse contaminant sources is critical for the successful management of mining-impacted catchments. 相似文献7.
Rachel R Hurley James J Rothwell Jamie C Woodward 《Journal of Soils and Sediments》2017,17(11):2648-2665
Purpose
Manchester is often heralded as the first industrial city. Large volumes of physical and liquid contaminants were released into its river network throughout the industrial period up to the latter part of the twentieth century. Water quality has improved dramatically in recent decades, but, given their environmental significance, it is important to ascertain the extent to which a legacy of contamination persists in the modern bed sediments.Materials and methods
Fine-grained bed sediments were sampled at 40 sites in the Mersey and Irwell catchments. Sediments were wet sieved to isolate the <63-μm grain size fraction. Metal concentrations were determined using XRF. Particle size characteristics were also measured. Sediments were subjected to a five-step sequential extraction procedure to ascertain the environmental significance of metal concentrations. Alongside archival research of past industry, enrichment factors, multivariate statistical techniques and conditional inferences trees were used to identify sources of heavy metals.Results and discussion
Bed sediment-associated heavy metal(loid) concentrations were as follows: As (9.89–110 mg kg?1), Cr (76.5–413 mg kg?1), Cu (53.1–383 mg kg?1), Pb (80.4–442 mg kg?1) and Zn (282–1020 mg kg?1). Enrichment factors ranged from moderate to extremely severe, with Pb showing the greatest enrichment across the catchments. Chemical mobility was generally low, but metal(loid) partitioning identified the influence of anthropogenic sources. Statistical analysis highlighted a number of point sources associated with former industrial sites that operated during the industrial period. Conditional inference trees highlighted the role of the textile industry on Cu concentrations in addition to indicating the complexity of sources, fluxes and stores of sediment-associated contamination throughout the system.Conclusions
Fine-grained sediment-associated metal(loid)s in the Mersey and Irwell catchments are anthropogenically enriched. Concentrations also exceed sediment quality guidelines. A lack of distinct spatial patterning points to a complex network of contaminant inputs across the catchments, even in the headwaters. Whilst potential modern urban sources are likely to be important, spatial patterns and multivariate/data mining techniques also highlighted the importance of releases from former industrial sites as well as the reworking of historically contaminated floodplains and soils.8.
Isabel Párraga-Aguado Pedro Alcoba-Gómez Héctor M. Conesa 《Journal of Soils and Sediments》2017,17(10):2469-2480
Purpose
The use of municipal solid wastes (MSWs) as a low-cost source of organic matter for soils should be considered after discarding the environmental risks related to their metal(loid) load. The goal of this work was to assess the employment of a MSW as an organic amendment in two types of soil (an agricultural soil, A, and a metal(loid)-enriched mine tailings soil, T) attending to changes in soil properties and in plant growth, nutrition and metal(loid) translocation from roots to aerial parts of Zea mays L. (stalk, leaves, tassel, husk, cob and kernel).Materials and methods
After a comprehensive characterisation of each soil treatment (A, A + MSW, T, T + MSW), a pot-designed experiment was carried out. Soil solution was monthly monitored throughout the experiment, and metal(loid) concentrations were measured.Results and discussion
The MSW improved some fertility-related parameters in both soils, A and T: increased total and dissolved organic carbon, total nitrogen and soil microbiology. However, an increase in 0.01 M CaCl2-extractable metal(loid) concentration was also observed. No differences in dry biomass were found between amended and not amended treatments. A fractionation of metal(loid) concentrations among plant organs occurred. For instance, the highest Cu and Pb concentrations were found in roots, while for Zn occurred in the stalk and the cob. The amended treatments favoured the accumulation of Mn in all plant organs. Kernels showed in general the lowest metal(loid) concentrations.Conclusions
The addition of municipal solid wastes as organic amendment could be a suitable tool to increase soil fertility. However, due to the high metal(loid) content of this particular MSW, its use on agricultural soils would not be appropriate. By other hand, along with the improvement of soil fertility, the MSW was useful to promote plant development in the mine tailings soil which should be then considered as a potential tool to promote plant establishment in those metal(loid)-impacted soils.9.
Jana Vašíčková Tereza Kalábová Klára Komprdová Jan Priessnitz Michal Dymák Jan Lána Lucia Škulcová Lucie Šindelářová Milan Sáňka Pavel Čupr Radim Vácha Jakub Hofman 《Journal of Soils and Sediments》2013,13(5):906-915
Purpose
The toxicity of 36 dredged sediments from the Czech Republic was investigated using a large battery of bioassays. The aim of this study was to investigate the feasibility of ecotoxicity testing in general and of individual bioassays more specific and to investigate how the results of bioassays are determined by the physicochemical properties of sediment samples and/or sediment contamination.Material and methods
In 2008 and 2010, 36 sediment samples were collected from rivers and ponds and from sediment heaps in different parts of the Czech Republic. Both their physicochemical properties and their levels of contamination with POPs and heavy metals were analyzed. The ecotoxicities of the sediments were evaluated using the four bioassays from the new Czech directive 257/2009 Coll. concerning the application of dredged sediments on agricultural land (Enchytraeus crypticus reproduction, Folsomia candida reproduction, Lactuca sativa root elongation, and potential ammonium oxidation). The results of the four directive bioassays were compared with the results of other soil bioassays (Caenorhabditis elegans mortality, Eisenia fetida avoidance and reproduction) and eluate bioassays (Daphnia magna immobilization, Pseudokirchneriella subcapitata growth inhibition test, and Vibrio fischeri luminescence).Results and discussion
We demonstrate that the battery suggested in Czech directive 257/2009 Coll. is highly effective in identifying toxic samples; these bioassays clearly revealing different types of toxicity and different exposure routes. Shorter alternative bioassays may be added especially when fast toxicity identification is needed. Eluate bioassays identified samples potentially hazardous to aquatic ecosystems. Their inclusion into the assessment scheme should be considered if the goal of assessment is also the protection of aquatic ecosystems. The results of our multivariate analysis show that specific physicochemical properties and contamination may affect bioassay responses. C. elegans was the most sensitive bioassay to physicochemical properties and also to organic contamination, while eluate bioassays were sensitive to heavy metal pollution.Conclusions
Most effects detected by the bioassays could not be explained by the levels of toxicants measured or by the natural characteristics of sediments. Our results show that bioassays are irreplaceable in dredged sediment risk assessment because they complement information provided by chemical analyses. 相似文献10.
Dariusz Ciszewski Urszula Kubsik Urszula Aleksander-Kwaterczak 《Journal of Soils and Sediments》2012,12(9):1445-1462
Purpose
The Matylda catchment, in southern Poland, was polluted by the discharge of mine waters from a lead and zinc mine that inundated parts of a valley floor and caused the accumulation of metal-polluted sediments. After a partial reclamation of the mine site in the early 1980s, polluted sediments continue to accumulate on downstream floodplains and in fishponds. The aim of this study was to reconstruct the changes in metal dispersal during 100?years of mining and during the 40-year post-mining period and to propose a strategy for pollution mitigation in the area.Materials and methods
Analyses of Cu, Cd, Pb, Zn, Mn, Ca, Mg and Fe concentrations, speciation of heavy metals and mineralogical analyses were undertaken on overbank sediment cores and in stream sediments. Concentrations of the same elements and macro-ions soluble in stream waters were also determined.Results and discussion
Concentrations of Zn, Cd and Pb in the sediment profiles vary between 40,000 and 55,000, 300 and 600 and 30,000 and 50,000?mg?kg-1, respectively. Changes of metal concentrations and the stratigraphy of sediments from the floodplains, stream channels and fishponds suggest rapid changes of metal loads migrating downstream during both the mining and post-mining periods. Since the time of mine closure, fine-grained, mine-derived sediments (ca. 12?cm thick) have been the main source of pollution of post-mining sediments and surface waters. Closure of the mine was followed by a relatively short period of rapid redistribution of sediment-associated heavy metals in the stream channel. Since the 1980s, the floodplain and fishponds have received a constant supply of metals. It contrasts with the slow sediment accretion rate and a rapid decrease of metal concentrations in floodplain pools due to dilution by decomposed leaf litter. A fivefold increase of Cd content in waters over the 4.6?km reach of the Matylda stream indicates continuous leaching of this element from the contaminated valley floor.Conclusions
Unsuccessful mine site rehabilitation is due to leaching of mine-originated sediments dispersed over the valley bottom. However, the rate of metal remobilization over the last 40?years is low because of the small thickness and widespread anoxic conditions that prevail within both recent and mine-originated sediments and the alkaline pH of stream water, which reduces metal mobility. Distribution of the contaminated layer over a large area of the valley bottom precludes cost-efficient catchment rehabilitation. 相似文献11.
Manhattan Lebrun Florie Miard Romain Nandillon Gabriella S. Scippa Sylvain Bourgerie Domenico Morabito 《Journal of Soils and Sediments》2018,18(6):2188-2202
Purpose
Anthropic activities induce severe metal(loid)s contamination of many sites, which is a threat to the environment and to public health. Indeed metal(loid)s cannot be degraded, and thus accumulate in soils. Furthermore, they can contaminate surrounding ecosystems through run-off or wind erosion. This study aims to evaluate the phytostabilization capacity of Salix viminalis to remediate As and Pb highly contaminated mine site, in a biochar-assisted phytoremediation context and to assess biochar particle size and dose application effects.Materials and methods
To achieve this, mesocosm experiments were conducted using the contaminated technosol and four different size fraction of one biochar as amendment, at two application rates (2 and 5%). Non-rooted cuttings of Salix viminalis were planted in the different mixtures. In order to characterize the mixtures, soil pore waters were sampled at the beginning and at the end of the experiment and analyzed for pH, electrical conductivity, and metal(loid) concentrations. After 46 days of Salix growth, roots, stems, and leaves were harvested and weighed, and As and Pb concentrations and distributions were measured.Results and discussion
Soil fertility improved (acidity decrease, electrical conductivity increase) following biochar addition, whatever the particle size, and the Pb concentration in soil pore water decreased. Salix viminalis did not grow on the non-amended contaminated soil while the biochar amendment permitted its growth, with a better growth with the finest biochars. The metal(loid)s accumulated preferentially in roots.Conclusions
Fine biochar particles allowed S. viminalis growth on the contaminated soil, allowing this species to be used for technosol phytostabilization.12.
João Canário Laurier Poissant Martin Pilote Christian Blaise Philippe Constant Jean-François Férard François Gagné 《Journal of Soils and Sediments》2014,14(1):196-203
Purpose
This paper reports a toxicity survey of Canadian Arctic marine sediments. During the Amundsen scientific cruise, eight sites distributed across the Canadian Arctic and sub-Arctic regions were selected to highlight sensitive areas affected by either atmospheric deposition, ocean current, river drainage, or anthropogenic activities. As part of the Canadian-led ArcticNet research program, this study aims to monitor and to better understand potential changes likely to impact the Arctic.Materials and methods
Surface sediments were investigated with bioanalytical tests to assess sediment toxicity. Testing of sediment elutriates was undertaken with the ARTOXKIT M, Microtox liquid phase (MLPA), and ROTOXKIT M toxicity assays, while whole sediment testing was carried out with the Microtox solid phase assay (MSPA) toxicity test procedure. Sediment mercury (Hg) content was also determined in each sample since Hg transport and toxicity is specifically an important issue in the Arctic and is generally a key indicator of the pollution status in many aquatic ecosystems.Results and discussion
Based on bioassay results and sediment granulometric criteria, these Arctic sediments must be considered nontoxic. However, based on MSPA half maximal inhibitory concentrations (IC50s) and/or MLPA threshold effect concentration (TEC) values, some degree of toxicity may be measureable particularly in the sediments located in southern and northeast Hudson Bay. The Hudson Bay watershed drains 30% of Canadian rivers and extends to northern USA. Despite the large Hg concern in the Arctic, the input of local or long-range Hg sources does not appear to be a contributing factor to sediment toxicity.Conclusions
These initial results are valuable in that they set baseline quality levels for these sediments as of 2005. As such, future comparisons can be made to assess temporal and spatial trends. Human activity and climate change is expected to impact these regions in the future, resulting in further reduction of sea ice extent, access to new Arctic seaways, and drilling associated with the exploitation of natural resources. 相似文献13.
Andrés Rodríguez-Seijo Daniel Arenas-Lago Manoel Lago-Vila Flora A. Vega Luisa Andrade Couce 《Journal of Soils and Sediments》2014,14(4):785-793
Purpose
Metal mining is the main cause of soil contamination caused by heavy metals. Mine tailings and minespoils generally offer hostile environments for plant growth due to their low nutrient availability, low organic matter content, and high trace metal content. This study was carried out with the aim of characterizing the soils that have developed on the tailings from an abandoned lead and zinc mine in Galicia (NW Spain) and determining the soil factors that limit revegetation.Materials and methods
We selected three zones: (a) the minespoils, (b) in the mining area, and (c) the settling pond, where the sludge from the flotation process was deposited. A control soil was also sampled outside of the mining area. We analyzed the physicochemical properties and metal levels in the mine spoil and soil samples we collected.Results and discussion
The results indicate that the main physical limitations of minesoils are their low effective depth, high porosity and stoniness, while the main chemical limitations are low organic matter content and low CEC and an imbalance between exchangeable cations. These minesoils are strongly affected by high Zn and Pb levels which hinder revegetation.Conclusions
As high concentrations of toxic trace elements and a high pH are important factors in limiting the plant growth, the restoration procedure must overcome the oxidation processes by adding organic amendments that also contribute towards fixing heavy metals or by implanting spontaneous vegetation adapted to the mine conditions, such as common broom (Cytisus scoparius) or white birch (Betula celtiberica). 相似文献14.
Xinyu Mao Fengxiang X. Han Xiaohou Shao Zikri Arslan Jacqueline McComb Tingting Chang Kai Guo Ahmet Celik 《Journal of Soils and Sediments》2016,16(10):2344-2353
Purpose
Extensive deposition of Pb, As, and Cs in soils may damage ecosystems and human’s health. Soil washing is the most conventional remediation method, and its efficiency depends on metal solubility in soil. This study aims to optimize operating variables of electro-kinetic field (EKF)-enhanced soil washing procedures.Materials and methods
Soil samples from a Mississippi River Delta rice field were homogeneously spiked with Pb, As, and Cs, and contaminated soil was aged for 3 months. The remediation involved a first stage electro-kinetic process, followed by a soil washing procedure. Soil pH changes under EKF were studied. Effects of citric acid and reversed EKF were investigated for alleviating possible alkaline precipitation. In the washing procedure, soil washing time and cycles with different extractants were examined. The overall EKF-enhanced soil washing efficiencies were discussed as well.Results and discussion
The implement of EKF offered an acidic soil environment around the anode areas for solubilizing metal(loid)s. Combined with EKF, citric acid was more conductive to desorb metal(loid)s. In addition, the reversed EKF effectively alleviated metal(loid) precipitation caused by alkalization in the first stage cathode areas. The EKF significantly enhanced metal(loid) extractions in the anode area of soils using Na2EDTA, CaCl2, and citric acid at pH of 2. The most preferable removal of Pb (80–98 %), As (48–63 %), and Cs (10–13 %) was achieved with three extractants. CaCl2 and citric acid were proved to be suitable alternatives to Na2EDTA for Pb extraction. A washing process of 2 h extraction with double washing cycles was optimized.Conclusions
Soil washing time and cycles were major factors governing the metal(loid) removal from soil. Washing process of 2 h extraction with double cycles was optimized for further extraction based on higher washing efficiency. The EKF effectively improved washing efficiency while some electrical parameters need further studies for cost performance consideration.15.
Purpose
We investigated the effect of growth strategy (i.e., single or mixed plant types) of two emergent plants (i.e., Phragmites australis and Typha orientalis) on the distribution of phthalic acid esters (PAEs) and their monoester metabolites (PAMs) in the sediments and roots in two adjacent shallow lakes in Tianjin, China, as well as the removal of PAEs from the sediments.Materials and methods
Dibutyl phthalate (DBP), di-2-ethylhexyl phthalate (DEHP), and their PAMs were measured in sediments and roots sampled on 18th May 2010. PAE-degrading bacteria and phospholipid fatty acid (PLFA) of the sediment samples were also analyzed.Results and discussion
The results showed that DBP, DEHP, and their PAMs were detected in nearly all of the samples, and the PAE concentrations were 1 to 2 orders of magnitude higher than those of their corresponding monoester metabolites. The PAE distribution patterns in sediments from the two lakes were different and influenced by plant growth strategy. Phytoavailability of PAEs was also affected by plant growth strategy.Conclusions
Compared with the non-rhizosphere sediments, the total organic carbon-normalized PAE concentration in the rhizosphere sediments decreased in the presence of the emergent plants. The PAE removal from the rhizosphere sediments was related not only to plant species but also to growth strategy, which was consistent with the findings of PLFA. The enhancement of PAE biodegradation in the rhizosphere was mainly the result of changes in the microbial community structure for different plant species and in microbial biomass for the same plant species. 相似文献16.
Carmen Pérez-Sirvent Carmen Hernández-Pérez María José Martínez-Sánchez Mari Luz García-Lorenzo Jaume Bech 《Journal of Soils and Sediments》2017,17(5):1384-1393
Purpose
This study was undertaken to determine the feasibility of using three aquatic macrophytes, Phragmites australis, Juncus effusus and Iris pseudacorus, to phytoextract potentially toxic elements (PTEs) from a contaminated area by mining activities.Materials and methods
An artificial pond was constructed with two topsoils (yellow and black samples) collected from Portman Bay. In order to simulate the mixing with carbonate materials, which naturally occurs in this area, a stabilisation approach was applied by mixing with 30 % of limestone filler. Three replicates of each type of soil have been prepared in pots for the selected species. The total PTEs content (arsenic, cadmium, copper, iron, lead and zinc) was determined and the bioconcentration factor (BCF) and transfer factor (TF) calculated.Results and discussion
Soil samples showed high PTEs content as a result of mining activities. As regards the root contents, the PTEs is higher in yellow samples (YS) than in black ones, because in these samples the PTEs content that could be mobilised is higher. The BCF results were higher than unity for arsenic, copper, lead and cadmium for I. pseudacorus and P. australis growing on YS soil. Overall, copper and manganese showed a larger number of plants with BCF higher than unity. The PTEs content in leaves is low, and the TF results are lower than unity in almost all samples.Conclusions
The results indicate that it is possible to use the selected species for phytostabilisation of soils contaminated with PTEs. J. effusus, P. australis and I. pseudacorus could be considered as tolerant, and natural or artificial wetlands containing these species could be used for remediation purposes.17.
Hossain M. Anawar N. Canha I. Santa-Regina M. C. Freitas 《Journal of Soils and Sediments》2013,13(4):730-741
Purpose
The impacts of mining contaminations and physico-chemical properties and geochemistry of mine tailings on the density, richness, biodiversity, evolution and succession of plant species and vegetation recovery in the mining area is very poorly reported in the literature. Therefore, the present study conducted an investigation on vegetation development and succession of plant communities at the abandoned São Domingos pyrite mining area.Materials and methods
We conducted the field survey to estimate the vegetation development and succession of plant communities, collect vegetation (plant species, lichen and moss) and tailing (and soil) samples, and finally analyzed the physico-chemical and geochemical properties and metal levels in mine tailings, soil and vegetation samples.Results and discussion
The results showed that the communities of low height and biomass like grass, legume, shrub, moss and lichen were dominating on the mine tailings and waste dumps at the inner sites and center of the mine, and the vegetation coverage was explicitly very poor. The reddish brown colluvia had poor soil quality, but high acidity and metal concentrations. However, at the outer edge of the mine the loamy soil and relatively lower acidity and metal contamination favored the higher vegetation cover and a gradual increase in the number of species and plant succession, where the taller, higher biomass and broad leaf trees were abundantly grown forming a dense forest and canopy. The succession of several plant communities dominating in the mining area, vegetation coverage and species richness were strongly related to the different levels of contamination, soil properties and adverse factors of mine tailings.Conclusions
Although the high concentrations of toxic trace elements and low pH soil are important factors for limiting the plant growth, however, proper soil development with enriched nutrients and properties on mining wastes, by either natural or external soil aided process, can help to promote the high vegetation growth, mine rehabilitation and ecological restoration of the mining degraded lands. 相似文献18.
Rosa Devesa-Rey M. Luz Iglesias Rogelio Pérez-Moreira Francisco Díaz-Fierros M. Teresa Barral 《Journal of Soils and Sediments》2013,13(5):932-942
Purpose
This work explores the application of the use of Zn, Cu, and Pb relative contents as a new type of normalization method for geochemical properties of soils and sediments in an Atlantic Basin (Anllóns River, NW Spain). The method is based on the conservative behavior of these elements, which exhibit a certain concentration ratio that remains stable as long as there are no human disturbances.Materials and methods
The average relative contents of Zn, Cu, and Pb were calculated by dividing the concentration of each metal in soils or sediments, in the <63-μm fraction, by the sum of Zn, Cu, and Pb, expressed as a percentage. The evaluation of the sum of the average relative concentrations of Zn, Cu, and Pb (Ri), together with three standard deviations for each element, namely, Ri ± 3Si, allows a hexagon to be constructed, represented in ternary diagrams of Zn:Cu:Pb. Following the method proposed by Weng et al. (Environ Geol 45:79–85, 2003), those samples falling outside the hexagon must be considered outliers.Results and discussion
Results obtained confimed the conservative behavior between the relative contents of Zn, Cu, and Pb in surficial samples (soils, bed, and suspended sediments). Only sediment cores displayed nonconservative behavior, showing a marked Pb enrichment, with respect to the surficial samples. When Zn, Cu, and Pb relative contents were plotted in ternary diagrams, outliers were best classified when the hexagon was drawn with standard deviations of samples from the study area. The hexagon drawn with an international database of soils and sediments showed a poorer classification of outliers.Conclusions
The results showed that total Zn, Cu, and Pb relative contents may be employed to investigate anthropogenic disturbances of these elements in soils and sediments of the Anllóns River Basin, thus corroborating that this type of normalization may be employed as a tool to assess outliers in a contaminated area. 相似文献19.
Catrina Cofalla Sebastian Hudjetz Sebastian Roger Markus Brinkmann Roy Frings Jan W?lz Burkhard Schmidt Andreas Sch?ffer Ulrike Kammann Markus Hecker Henner Hollert Holger Schüttrumpf 《Journal of Soils and Sediments》2012,12(3):429-442
Purpose
Flood events are expected to increase both in intensity and frequency due to climate change in the near future. From an environmental toxicology perspective, there is concern that such flood events could lead to the remobilization of contaminated sediment layers in rivers. The aim of this pilot study was to establish a novel and interdisciplinary framework combining methods of hydrodynamic engineering and ecotoxicological assessment to enable investigation of the potential risks associated with such remobilization events.Materials and methods
Formulated sediment was prepared according to OECD guideline 218 and spiked with a mixture of four polycyclic aromatic hydrocarbons (phenanthrene, chrysene, pyrene, benzo[a]pyrene) at concentrations of 3.3?C8.3?mg?kg?1 dry weight. Rainbow trout (Oncorhynchus mykiss) were exposed as test animals to re-suspended sediments in three out of five experiments. The experiments were carried out in an annular flume designed to investigate transport behaviour of fine-grained sediments. Several physicochemical (e.g. pH) and sedimentological (e.g. turbidity) parameters were measured to characterise environmental conditions and erosion behaviour of sediments. Furthermore, exposure concentrations were measured by means of an in vitro assay (7-ethoxyresorufin-o-deethylase (EROD), RTL-W1 cell assay) and chemical analysis.Results and discussion
Preparation and spiking of large amounts of formulated sediments were feasible but not practical. Successful spiking could be confirmed by the bioanalytical methods with the spiked sediments showing significantly elevated EROD induction compared to control sediments. Conditions within the annular flume remained stable throughout all experiments and were adequate to support rainbow trout. Flood events were successfully simulated, resulting in re-suspension of formulated sediment. Different erosion behaviours of sediments during the simulated flood events were observed and could be associated with changes in microbial composition of sediments due to differences in storage conditions. Therefore, maintaining constant storage conditions of formulated sediments is crucial to enable consistency and comparability among erosion experiments.Conclusions
This study clearly demonstrated the feasibility of a combined hydro-toxicological approach in support of the investigation of the potential ecotoxicological relevance of sediment re-suspension events. However, based on the results presented here, it is recommended to include additional physicochemical parameters, such as redox potential and conductivity, and to extend the experimental setup to natural sediments and different aquatic organisms. Future studies will use natural sediments containing representative microbial communities and extracellular polymeric substances to enable extrapolation from the annular flume to conditions in natural flowing waters. 相似文献20.
Efrén Garcia-Ordiales Jorge Loredo Stefano Covelli José M. Esbrí Rocio Millán Pablo Higueras 《Journal of Soils and Sediments》2017,17(7):1893-1904