Accumulation of Heavy Metals by Amur Bay Sediments (the Sea of Japan) under the Effect of Biochemical Factors     

Polyakov  D. M.  Mar’yash  A. A.  Mozherovskii  A. V. 《Water Resources》2019,46(2):209-213

Water Resources - The average concentrations of elements Fe, Mn, Zn, Pb, Cu, Cr, V, Co, Cd, Ni, As, and Mo in the subcolloidal fraction of bottom sediments were determined in the northern and...  相似文献   

Evaluation of the removal of heavy metals in a natural wetland impacted by mining activities in Mexico     

Juan Miguel Gómez-Bernal  Esther Aurora Ruiz-Huerta  María Aurora Armienta-Hernández  Víctor Manuel Luna-Pabello 《Environmental Earth Sciences》2017,76(23):801

This research is focused on evaluating heavy metals (Cd, Cu, Fe, Mn, Pb, and Zn) uptake and removal by Eleocharis ovata, Cyperus manimae, Typha dominguensis, and Pteridium aquilinum in a natural wetland impacted by mining activities. We analyzed heavy metals content and distribution in native plants, soils, and water of a semipermanent natural wetland in Taxco de Alarcón, Guerrero, and we also determined the physicochemical characteristics of the water. Translocation factor (TF) and bioconcentration factor (BCF) were evaluated. Results showed that physical and chemical conditions are favorable for plants development. Correlation analysis showed a good and positive relation (0.95) between Cu and Pb in soils and plants. In the analyzed matrices: Zn (0.62–2.20 mg/L) exceeded the permissible limits in water, high concentrations of Pb and Zn (26.57–525.67 and 266.67–983.33 mg/kg, respectively) were detected in the studied soils, and Pb exceeded the normal range for E. ovata and P. aquilinum in the analyzed plants. Uptake of heavy metals in the tissues of different species was found in the following order: root > leaf. Data of TF and BCF showed that E. ovata is a tolerant plant with respect to heavy metals exposure since TF value was greater than 1. This study showed that E. ovata could be considered as a bioaccumulator of heavy metals in contaminated soils.  相似文献   

Erratum to: Flare-Shaped Acoustic Anomalies in the Water Column Along the Ecuadorian Margin: Relationship with Active Tectonics and Gas Hydrates     

Francois Michaud  Jean-Noël Proust  Alexandre Dano  Jean-Yves Collot  Grâce Daniella Guiyeligou  María José Hernández Salazar  Gueorgui Ratzov  Carlos Martillo  Hugo Pouderoux  Laure Schenini  Jean-Frederic Lebrun  Glenda Loayza 《Pure and Applied Geophysics》2016,173(4):1429-1429

  相似文献   

Paleoflood events recorded by speleothems in caves          下载免费PDF全文

Fernando Gázquez  José María Calaforra  Paolo Forti  Heather Stoll  Bassam Ghaleb  Antonio Delgado‐Huertas 《地球表面变化过程与地形》2014,39(10):1345-1353

Speleothems are usually composed of thin layers of calcite (or aragonite). However, cemented detrital materials interlayered between laminae of speleothemic carbonate have been also observed in many caves. Flowstones comprising discontinuous carbonate layers form due to flowing water films, while flood events introduce fluviokarstic sediments in caves that, on occasion, are recorded as clayey layers inside flowstones and stalagmites. This record provides a potential means of understanding the frequency of palaeofloods using cave records. In this work, we investigate the origin of this type of detrital deposit in El Soplao Cave (Northern Spain). The age of the lowest aragonite layer of a flowstone reveals that the earliest flood period occurred before 500 ka, though most of the flowstone formed between 422 +69/‐43 ka and 400 +66/‐42 ka. This suggests that the cave was periodically affected by palaeoflood events that introduced detrital sediments from the surface as a result of occasional extreme rainfall events, especially at around 400 ka. The mineralogical data enable an evolutionary model for this flowstone to be generated based on the alternation of flood events with laminar flows and carbonate layers precipitation that can be extrapolated to other caves in which detrital sediments inside speleothems have been found. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

Assessment of evaporation and water fluxes in a column of dry saline soil subject to different water table levels   总被引：1，自引：0，他引：1       下载免费PDF全文

María Fernanda Hernández‐López  Jorge Gironás  Isabelle Braud  Francisco Suárez  José Francisco Muñoz 《水文研究》2014,28(10):3655-3669

Dry saline soils are common in the arid and hyper‐arid basins located in the Chilean Altiplano, where evaporation from shallow groundwater is typically the major component of the water balance. Thus, a good understanding of evaporation processes is necessary for improving water resource planning and management in these regions. In this study, we conducted laboratory experiments with a natural saline soil column to estimate evaporation rates and assess the liquid and water vapor fluxes under different water table levels. Water content, electrical conductivity and temperature at different depths were utilized to assess the liquid and water vapor fluxes in the soil column. We observed movement of water that dissolves salts from the soil and transports them to areas in the column where they accumulate. Isothermal liquid flux was predominant, while thermal and isothermal liquid and thermal water vapor fluxes were negligible, except for deep water table levels where isothermal and thermal water vapor fluxes had similar magnitude but opposite directions. Differences observed in total fluxes for all water table levels were due to different upward and downward fluxes, which depend on changes in water content and temperature within the soil profile. Both the vapor flux magnitude and direction were found to be very sensitive to the choice of empirical parameters used in flux quantification, such as tortuosity and the enhancement factor for local temperature gradients in the air phase within the column. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

A smoothed ANOVA model for multivariate ecological regression   总被引：3，自引：3，他引：0  

Marc Marí-Dell’Olmo  Miguel A. Martinez-Beneito  Mercè Gotsens  Laia Palència 《Stochastic Environmental Research and Risk Assessment (SERRA)》2014,28(3):695-706

Smoothed analysis of variance (SANOVA) has recently been proposed for carrying out disease mapping. The main advantage of this approach is its conceptual simplicity and ease of interpretation. Moreover, it allows us to fix the combination of diseases of particular interest in advance and to make specific inferences about them. In this paper we propose a reformulation of SANOVA in the context of ecological regression studies. This proposal considers the introduction in a non-parametric way of one (or several) covariate(s) into the model, explaining some pre-specified combinations of the outcome variables. In addition, random effects are also incorporated in order to model geographical variation in the combinations of outcome variables not explained by the covariate. Lastly, the model permits the decomposition of the variance in the set of outcome variables into different orthogonal components, quantifying the contribution of every one of them. The proposed model is applied to the geographical analysis of mortality due to malignant stomach neoplasm among women resident in the city of Barcelona (Spain). The available outcome variables are deaths grouped into two time periods, and a socioeconomic deprivation index is included as a covariate. The model has been implemented through INLA, a novel inference tool for Bayesian statistics.  相似文献   

Adsorption of Arsenite from Groundwater Using Titanium Dioxide          下载免费PDF全文

Miriam Z. López Paraguay  José Apolinar Cortes  Juan F. Pérez‐Robles  María T. Alarcón‐Herrera 《洁净——土壤、空气、水》2014,42(6):713-721

  相似文献   

Immobilisation of Pb and Zn in Soils Using Stabilised Zero‐valent Iron Nanoparticles: Effects on Soil Properties          下载免费PDF全文

María Mar Gil‐Díaz  Araceli Pérez‐Sanz  María Ángeles Vicente  María Carmen Lobo 《洁净——土壤、空气、水》2014,42(12):1776-1784

  相似文献   

Fluoride Biomonitoring around a Large Aluminium Smelter Using Foliage from Different Tree Species     

Judith Hebelen Rodriguez  Eduardo Daniel Wannaz  María Luisa Pignata  Andreas Fangmeier  Jürgen Franzaring 《洁净——土壤、空气、水》2012,40(12):1315-1319

In order to study the pollution gradient in the vicinity of a large aluminium production facility in Patagonia (Argentina), a passive biomonitoring was performed employing foliage from three tree species. Primary scope was to identify pollution gradients and to select suitable tree species which can be used as biomonitor plants in the study area. Therefore, leaves of Eucalyptus rostrata, Populus hybridus and different needle ages of Pinus radiata were collected at different distances from the industry and the fluoride concentration was analysed in washed and unwashed samples in order to determine the amount of external fluoride. Washing reduced the F‐concentrations by 24, 39 and 51% on average in E. rostrata, P. hybridus and P. radiata, respectively, indicating that species‐specific characteristics determine the accumulation and wash‐off of dust‐associated fluorine. F‐concentrations varied from 6 to 3652 ppm F in unwashed samples indicating a steep pollution gradient in the study area. The influence of F‐emissions was discernible in all samples up to a distance of 3500 m from the smelter. E. rostrata accumulated more fluorine than the other species at equal distance from the emission source. The present study confirms that aluminium smelting results in high F deposition in the study area. Establishing a biomonitor network around large emitters is suitable and feasible to evaluate the efficiency of air control measures.  相似文献   

Coherent structure dynamics and sediment particle motion around a cylindrical pier in developing scour holes   总被引：1，自引：1，他引：0  

Oscar Link  Christian González  María Maldonado  Cristián Escauriaza 《Acta Geophysica》2012,60(6):1689-1719

Recent investigations on the dynamics of the turbulent horseshoe vortex system (THV) around cylindrical piers have shown that the rich coherent dynamics of the vortical structures is dominated by low-frequency bimodal fluctuations of the velocity field. In spite of these advances, many questions remain regarding the changes of the flow and sediment transport dynamics as scour progresses. In this investigation we carry out laboratory experiments to register the development of the scour hole around a cylindrical pier in a fine-sand bed (d ₅₀ = 0.36 mm). We use the bathymetry measured in the experiment to simulate the flow field employing the detached-eddy simulation approach (DES), which has shown to resolve most of the turbulent stresses around surface-mounted obstacles. From these simulations we compare the dynamics of the THV to the flat-bed case, and analyze the effects on particle transport and sediment flux using the Lagrangian particle model of Escauriaza and Sotiropoulos (2011b) to study the impact of the changes of the flow on the sediment dynamics.  相似文献