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The quality assessment of tropical soils and sediments is still under discussion, with efforts being made on the part of governmental agencies to establish reference values. Energy dispersive X-ray fluorescence (EDXRF) is a potential analytical technique for quantifying diverse chemical elements in geological material without chemical treatment, primarily when it is performed at an appropriate metrological level. In this work, analytical curves were obtained by means of the analysis of geological reference materials (RMs), which allowed for the researchers to draw a comparison among the sources of analytical uncertainty. After having determined the quality assurance of the analytical procedure, the EDXRF method was applied to determine chemical elements in soils from the state of Pernambuco, Brazil. The regression coefficients of the analytical curves used to determine Al, Ca, Fe, K, Mg, Mn, Ni, Pb, Si, Sr, Ti, and Zn were higher than 0.99. The quality of the analytical procedure was demonstrated at a 95% confidence level, in which the estimated analytical uncertainties agreed with those from the RM's certificates of analysis. The analysis of diverse geological samples from Pernambuco indicated higher concentrations of Ni and Zn in sugarcane, with maximum values of 41 mg kg and 118 mg kg, respectively, and agricultural areas (41 mg kg and 127 mg kg, respectively). The trace element Sr was mainly enriched in urban soils with values of 400 mg kg. According to the results, the EDXRF method was successfully implemented, providing some chemical tracers for the quality assessment of tropical soils and sediments. [ABSTRACT FROM AUTHOR]

The concentrations of several trace elements and iron were determined in 26 soil samples from Belyi Island in the Kara Sea (West Siberian sector of Russian Arctic). The major types of soils predominating in the soil cover were sampled. The concentrations of trace elements (mg kg) varied within the following ranges: 119-561 for Mn, 9.5-126 for Zn, 0.082-2.5 for Cd, <0.5-19.2 for Cu, <0.5-132 for Pb, 0.011-0.081 for Hg, <0.5-10.3 for Co, and 7.6-108 for Cr; the concentration of Fe varied from 3943 to 37,899 mg kg. The impact of particular soil properties (pH, carbon and nitrogen contents, particle-size distribution) on metal concentrations was analyzed by the methods of correlation, cluster, and factor analyses. The correlation analysis showed that metal concentrations are negatively correlated with the sand content and positively correlated with the contents of silt and clay fractions. The cluster analysis allowed separation of the soils into three clusters. Cluster I included the soils with the high organic matter content formed under conditions of poor drainage; cluster II, the low-humus sandy soils of the divides and slopes; and cluster III, saline soils of coastal marshes. It was concluded that the geomorphic position largely controls the soil properties. The obtained data were compared with data on metal concentrations in other regions of the Russian Arctic. In general, the concentrations of trace elements in the studied soils were within the ranges typical of the background Arctic territories. However, some soils of Belyi Island contained elevated concentrations of Pb and Cd. [ABSTRACT FROM AUTHOR]

We modified the robust analysis of variance (RANOVA) method to calculate sampling uncertainty of selected trace elements determined in soil samples from two heterogeneous remote historic metal ore mining areas. Classical RANOVA is down-weighting the outlying values by replacing them during the calculation process with mean ± c·σr. Because the arithmetic mean is greatly influenced by outliers, it cannot represent a robust statistic. The main novel contribution of this work is use of median value that is independent on outliers and replace all extreme values during the calculation process with median ± 2·σr. In our work, 18 duplicate, composite soil samples were collected, digested with aqua regia in a closed microwave system, and analyzed twice for selected trace elements. To extract homogenous groups within sampling areas and make the results more accessible for interpretation, a cluster analysis was done. Subsequently, histograms of each element were prepared and statistical tests were applied to determine the normal distribution of datasets. For abnormally distributed elements, the outlying values were identified by four different methods: boxplot, mean ± c·σr, mean ± c·σ, and median ± 2·σr. For five elements, the amount of outliers identified by the median ± 2·σr procedure was less than 10 %, and for these elements, the sampling uncertainty was computed using a modified RANOVA method. The sampling uncertainty computed with this method was 28.9 % for Cd, 15.2 % for Co, 14.5 % for Mn, 12.7 % for Ni, and 16.3 % for Zn, whereas that computed with a traditional model was 16.7 % for Cd, 9.2 % for Co, 20.5 % for Mn, 17.9 % for Ni, and 16.3 % for Zn. [ABSTRACT FROM AUTHOR]

Bogra city is highly susceptible to environmental pollution due to overpopulation, rapid industrialization, and urbanization during the last decades. The levels of six trace elements (chromium, nickel, copper, arsenic, cadmium, and lead) in seven different land use soils in Bangladesh were assessed. The ranges of Cr, Ni, Cu, As, Cd, and Pb in studied soils were 6.3-256, 8.3-271, 13-279, 7.5-87, 0.09-29, and 5.3-624 mg/kg, respectively. The pollution load index (PLI) values for all land uses were higher than 1, indicating the progressive deterioration of soil due to trace elements contamination. In view of the potential ecological risk (PER), soils from all land uses showed moderate to very high potential ecological risk. Among the elements, As and Cd showed a higher potential ecological risk than the others. [ABSTRACT FROM AUTHOR]

Understanding the spatial variability of soil microelements and its influencing factors is of importance for a number of applications such as scientifically formulated fertilizer and environmental protection. This study used descriptive statistics and geostatistics to investigate the spatial variability of available soil Fe, Mn, Cu, and Zn contents in agricultural topsoil (0-20 cm) in an ecological functional zone located at Yanqing County, Beijing, China. Kriging method was applied to map the spatial patterns of available soil Fe, Mn, Cu, and Zn contents. Results showed that the available soil Cu had a widest spatial correlation distance (e.g., 9.6 km), which for available soil Fe, Mn, and Zn were only 1.29, 2.58, and 0.99 km, respectively. The values of C/sill for available soil Fe and Zn were 0.12 and 0.11, respectively, demonstrating that the spatial heterogeneity was mainly due to structural factors. The available soil Mn and Cu had the larger values of C/sill (i.e., 0.50 and 0.44 for Mn and Cu, respectively), which showed a medium spatial correlation. Mapping of the spatial patterns of the four microelements showed that the decrease trend of available soil Fe and Mn were from northeast to southwest across the study area. The highest amount of available soil Cu was distributed in the middle of the study area surrounding urban region which presented as a 'single island'. The highest amount of available soil Zn was mainly distributed in the north and south of the study area. One-way analysis of variance for the influencing factors showed that the lithology of parental materials, soil organic matter, and pH were important factors affecting spatial variability of the available microelements. The topography only had a significant influence on the spatial variability of available soil Fe and Mn contents, parental materials, and the land use types had little influence on the spatial variability. [ABSTRACT FROM AUTHOR]

Topsoil samples ( n = 40) were collected from a heavily industrialized region in Turkey. The region includes several scrap processing iron-steel plants with electric arc furnaces (EAFs), a petroleum refinery, a petrochemical complex, steel rolling mills, a natural gas-fired power plant, ship-breaking yards and very dense transportation activities. The region has undergone a rapid transition from an agricultural region to a heavily industrialized region in the last three decades. Collected soil samples were analyzed for 48 trace elements using inductively coupled plasma-mass spectrometry (ICP-MS). The elemental distribution pattern in the region indicated that Nemrut area with dense iron-steel production activities was a hotspot for elemental pollution. In addition to crustal elements, concentrations of anthropogenic trace elements (i.e., Fe, Zn, Pb, Mn, Cu, Cd, Cr and Mo) were very high in the area influencing many parts of the region. Elemental compositions of fugitive sources polluting the soil (i.e., paved and unpaved roads, slag piles, EAFs filter dust piles and coal piles) were also determined. The methods (enrichment factors [EFs] and the index of geoaccumulation [ I]) used for determination of pollution status of soil showed that Cr, Ag, Zn, As and Pb were the strongly contaminating elements for the region. Principal component analysis (PCA) clearly indicated that anthropogenic sources (steel production, refinery and petrochemical processes and traffic) were important sources in this region. [ABSTRACT FROM AUTHOR]

Extraordinary geogenic concentrations of cadmium (Cd) have been reported for some Jamaican soils. However, the bioavailability of the metal in these soils remains unknown. Here, the bioavailability of Cd in selected Jamaican soils was investigated through the determination of total and sequentially extractable concentrations in paired soil-plant (yam; Dioscorea sp.) samples ( n = 24), using neutron activation analysis and atomic absorption spectroscopy as primary analytical techniques. Our results indicate that total soil Cd varied widely (2.2-148.7 mg kg), and on average, total extractable Cd accounted for ~55 % of the total soil Cd. The exchangeable and oxidizable species averaged 1.5 and 6.4 % of the total Cd, respectively, and, based on Spearman analysis, are the best predictors of yam Cd. There is also good evidence to suggest that variation in the bioavailability of the metal is in part controlled by the geochemical characteristics of the soils analyzed and is best explained by pH, cation exchange capacity (CEC) and organic matter content (% LOI). [ABSTRACT FROM AUTHOR]

The aim of the study was to determine concentrations of some trace elements (lead, cadmium, chromium, and nickel) in soils along State Road 51 leading from Olsztyn to Olsztynek, northeastern Poland. The traffic flow had a significant effect on the content of heavy metals in soils lying along the road. Further away from the road, and under a lower traffic flow intensity, the amounts of contaminants originating from the motor traffic decreased. There was a pine forest growing by the road near Olsztyn, which served as a buffer zone for all the analyzed heavy metals. At all the sampling locations, the content of chromium was approximately the same as its natural concentration. The statistical analysis demonstrated that there was a strong negative correlation between the concentrations of nickel, lead, chromium, and cadmium in soils and the distance from the road. The biggest differences in the content of an individual element were determined for lead and the smallest ones-for cadmium. Emissions of trace elements depended on the differences in the traffic flow intensity, number, type, and speed of vehicles and on the atmospheric conditions as well as the distribution of buildings. [ABSTRACT FROM AUTHOR]

A long history of urbanization and industrialization has affected trace elements in New York City (NYC) soils. Selected NYC pedons were analyzed by aqua regia microwave digestion and sequential chemical extraction as follows: water soluble (WS); exchangeable (EX); specifically sorbed/carbonate bound (SS/CAR); oxide-bound (OX); organic/sulfide bound (OM/S). Soils showed a range in properties (e.g., pH 3.9 to 7.4). Sum of total extractable (SUM TE) trace elements was higher in NYC parks compared to Bronx River watershed sites. NYC surface horizons showed higher total extractable (TE) levels compared to US non-anthropogenic soils. TE levels increased over 10 year in some of the relatively undisturbed and mostly wooded park sites. Surface horizons of park sites with long-term anthropogenic inputs showed elevated TE levels vs. subsurface horizons. Conversely, some Bronx River watershed soils showed increased concentrations with depth, reflective of their formation in a thick mantle of construction debris increasing with depth and intermingled with anthrotransported soil materials. Short-range variability was evident in primary pedons and satellite samples (e.g., Pb 253 ± 143 mg/kg). Long-range variability was indicated by Pb TE (348 versus 156 mg/kg) and Hg TE (1 versus 0.3 mg/kg) concentrations varying several-fold in the same soil but in different geographic locations. Relative predominance of fractions: RES (37 %) > SS/CAR (22 %) > OX (20 %) > OM/S (10 %) > EX (7 %) > WS (4 %). WS and EX fractions were greatest for Hg (7 %) and Cd (14 %), respectively. RES was predominant fraction for Co, Cr, Ni, and Zn (41 to 51 %); SS/CAR for Cd and Pb (40 and 63 %); OM/S for Cu and Hg (36 and 37 %); and OX for As (59 %). [ABSTRACT FROM AUTHOR]

A comprehensive environmental evaluation was completed on 20 metals: two reference metals (Fe, Al) and several minor trace metals (As, Ba, Co, Cr, Cu, Mn, Ni, Pb, V, and Zn) for surface soils and sediments collected from 50 sites in Everglades National Park (ENP), the coastal fringes of Biscayne National Park (BNP), and Big Cypress National Preserve. Samples were prepared by acid digestion (EPA3050) and analyzed by ICP/MS detection (EPA6020). Although no widespread contamination was detected across the two parks and one preserve, there were some specific areas where metal concentrations exceeded Florida's ecological thresholds, suggesting that some metals were of concern. A screening-level evaluation based on a proposed effect index grouped trace metals by their potential for causing negligible, possible, and probable effects on the biota. For example, Cu in BNP and Cr and Pb in ENP were considered of concern because their adverse effect likelihood to biota was assessed as probable; consequently, these trace metals were selected for further risk characterization. Also, stations were ranked based on a proposed overall contamination index that showed that: site BB10 in BNP and sites E3 and E5 in ENP had the highest scores. The first site was located in a marina in BNP, and the other two sites were along the eastern boundary of ENP adjacent to current or former agricultural lands. An assessment tool for south Florida protected lands was developed for evaluating impacts from on-going Everglades restoration projects and to assist State and Federal agencies with resource management. The tool consists of enrichment plots and statistically derived background concentrations based on soil/sediment data collected from the two national parks and one preserve. Finally, an equally accurate but much simplified approach is offered for developing enrichment plots for other environmental settings. [ABSTRACT FROM AUTHOR]

Sewage sludge may be used as an agricultural fertilizer, but the practice has been criticized because sludge may contain trace elements and pathogens. The aim of this study was to compare the effectiveness of total and pseudototal extractants of Cu, Fe, Mn, and Zn, and to compare the results with the bioavailable concentrations of these elements to maize and sugarcane in a soil that was amended with sewage sludge for 13 consecutive years and in a separate soil that was amended a single time with sewage sludge and composted sewage sludge. The 13-year amendment experiment involved 3 rates of sludge (5, 10, and 20 t ha). The one-time amendment experiment involved treatments reflecting 50, 100, and 200 % of values stipulated by current legislation. The metal concentrations extracted by aqua regia (AR) were more similar to those obtained by Environmental Protection Agency (EPA) 3052 than to those obtained by EPA3051, and the strongest correlation was observed between pseudo(total) concentrations extracted by AR and EPA3052 and bioavailable concentrations obtained by Mehlich III. An effect of sewage sludge amendment on the concentrations of heavy metals was only observed in samples from the 13-year experiment. [ABSTRACT FROM AUTHOR]

The biomonitors Hypnum cupressiforme and Xanthoria parietina were used to assess the deposition of trace elements and their possible origin in the Prades Mountains, a protected Mediterranean forest area of NE Spain with several pollution sources nearby. Al, As, Cd, Co, Cu, Cr, Ni, Pb, Sb, Ti, V, and Zn were determined in 16 locations within this protected area. Soil trace element concentrations were also ascertained to calculate enrichment factors (EF) and use them to distinguish airborne from soilborne trace element inputs. In addition, lichen richness was measured to further assess atmospheric pollution. EF demonstrated to be useful not only for the moss but also for the lichen. Cd, Cr, Cu, Ni, and Zn presented values higher than three in both biomonitors. These trace elements were also the main ones emitted by the potential sources of pollutants. The distance between sampling locations and potential pollution sources was correlated with the concentrations of Cu, Sb, and Zn in the moss and with Cr, Ni, and Sb in the lichen. Lichen richness was negatively correlated with lichen Cu, Pb, and V concentrations on dry weight basis. The study reflected the remarkable influence that the pollution sources have on the presence of trace elements and on lichen species community composition in this natural area. The study highlights the value of combining the use of biomonitors, enrichment factors, and lichen diversity for pollution assessment to reach a better overview of both trace elements' impact and the localization of their sources. [ABSTRACT FROM AUTHOR]

Soil amendment by phosphogypsum (PG) application becomes of increasing importance in agriculture. This may lead, however, to soil, plant, and groundwater contamination with trace elements (TEs) inherently present in PG. Monitoring of selected TEs (Pb, Zn, Cu, and Cd) distribution and mobility in a Mediterranean red soil profile has been performed in soil parcels applied with PG over a 16-month period. Concentrations were measured in soil and plant samples collected from various depth intervals at different points in time. TEs sequential extraction was performed on soil and PG samples. Results showed soil profile enrichment peaked 5 months after PG application for Cd, and 12 months for Pb, Zn, and Cu. Rainwater, pH, total organic carbon, and cationic exchange capacity were the main controlling factors in TEs accumulation in soils. Cd was transferred to a soil depth of about 20 cm. Zn exhibited mobility towards deeper layers. Pb and Cu were accumulated in around 20-55-cm-deep layers. PG increased the solubility of the studied TEs; PG-applied soils contained TEs bound to exchangeable and acid-soluble fractions in higher percentages than reference soil. Pb, Zn, and Cu were sorbed into mineral soil phases, while Cd was mainly found in the exchangeable (bio-available) form. The order of TEs decreasing mobility was Zn > Cd > Pb > Cu. Roots and leaves of existed plants, Cichorium intybus L., accumulated high concentrations of Cd (1-2.4 mg/kg), exceeding recommended tolerable levels, and thus signifying potential health threats through contaminated crops. It was therefore recommended that PG should be applied in carefully established, monitored, and controlled quantities to agricultural soils. [ABSTRACT FROM AUTHOR]

Selected trace metals were estimated by atomic absorption spectrometry in the water and soil samples collected from the remote region of Himalaya. The soil samples were analysed for soluble and acid extractable fraction of trace metals. In water samples, Ca, Na, Mg and K emerged as dominant contributors, whereas, Ca, Na, K, Mg, Fe and Pb were estimated at comparatively higher levels in the water extract of the soil. In case of acid extract of the soil samples, Ca, K, Fe, Mg, Mn and Na were found at elevated concentrations. Based on mean levels of the metals, following decreasing concentration order was observed in water samples: Ca > Na > Mg > K > Pb > Co > Cu > Zn > Mn > Cr > Fe > Cd > Li, however, in the acid extract of the soil, following order was noted: Ca > K > Fe > Mg > Mn > Na > Pb > Zn > Cr > Li > Cu > Co > Cd. The correlation study revealed appreciably diverse mutual relationships of trace metals in the water and soil samples. The multivariate cluster analyses exhibited divergent apportionment of trace metals in water and soil samples. Among the trace metals, Cd, Pb, Li, Zn, Cr, Cu, Mn and Co exhibited extreme to significant anthropogenic enrichment in the soil samples, while the rest of the metals were mostly contributed by the natural processes. [ABSTRACT FROM AUTHOR]

n investigation was performed to measure concentrations of major and trace elements in surficial wetland sediments in the southern Tibetan Plateau in order to assess the sediment quality. Results showed that most of elements have concentrations comparable to those of the Tibetan surface soil (TSS) except for As, Ca, Cs, Sr, and Cu. Correlation analysis indicated that most elements were highly associated with major crustal elements, suggestive of their common natural origin. Sediment quality assessment revealed that the wetlands are unpolluted with most of trace elements except for Cs and As, which are likely associated with organic matters and biological activities. Despite that the wetland sediments are minimally influenced by either local or long-transported anthropogenic pollutants, and no notable trace element pollutants were detected, As was found in elevated concentrations which far exceed the level above which harmful effects on wildlife and humans are likely to be observed. [ABSTRACT FROM AUTHOR]

In order to monitor changes in the concentrations of metals in the soil, different microbial indices such as BIOLOG®, microbial carbon (Cmic), basal respiration, and culturable microbe’s most probable number were used. We compared these methods and wanted to discover which method was the best at measuring slight changes in the amounts of heavy metals. Factor analyses were applied to the BIOLOG® data and metal concentrations so the combined effects of heavy metals on microbes could be analyzed via statistical data reduction and the distribution patterns of metal concentration could also be revealed. The results showed that the BIOLOG® method could barely detect subtle characteristic changes in the soil samples, while the Cmic method was more sensitive. Furthermore, different heavy metals did not have the same origin/source, and their effects on microbial indices should be analyzed separately. Significant positive correlations between Cmic and metals were observed and suggested the limitation of using traditional microbial parameters as metal pollution indicators. Among all the soil characteristics in our study, pH seemed to be the most active abiotic factor that affected microorganisms. [ABSTRACT FROM AUTHOR]

In this paper, we surveyed the concentration of nine trace elements (As, Cd, Cu, Fe, Mn, Ni, Pb, Tl and Zn) in bermudagrass ( Cynodon dactylon) 3 years after the mine spill in Aznalcóllar (south Spain). The results were compared with those that had been obtained for the same species in a previous study, 18 months after the accident. Three types of soil condition were determined: i) unaffected soils (UN, control); ii) cleaned up and amended soils (A, amended); and (iii) non-amended soils, inaccessible to the clean-up and remediation operations (NA, non-amended). The trace element concentrations in the plants were lower than those reported in the first sampling for both washed (plant tissues) and unwashed plants (as consumed by herbivores). Apart from Cd, trace elements concentrations (plant tissues) were similar in the A and the UN soils. In the NA soils, the Cd, Fe, Mn, Zn and Pb levels in unwashed plants were excessive for animal consumption. This wild grass seems to be suitable as a soil stabilizer for spill affected soils and as a biomonitor for soil pollution by some trace elements (As, Cu and Zn); however, its potential for phytoextraction is negligible. [ABSTRACT FROM AUTHOR]

Trace element contamination caused by mining is a serious environmental problem. The potential effects of exploiting the Yunfu pyrite mine (southern China) on soil were investigated by determining trace elements in 56 surface soil samples from the vicinity of the Yunfu pyrite mine. The samples were acid dissolved and measured by an inductively coupled plasma mass spectrometry (ICP-MS). Principal component analysis and hierarchical cluster analysis were used to identify factors influencing the trace element contents and possible sources of the trace elements. The degree of trace element pollution was determined using the geological accumulation index Igeo. Monte Carlo simulations were used to assess the health risks posed. The results show that (1) six factors (parent material, mining activities, ore composition, rainfall, terrain, and other inputs) strongly affected the trace element contents of the soil samples. (2) There were three groups of trace elements, according to their possible sources. One group (Cs, Ga, Ge, Hf, Nb, Rb, Ta, Th, Ti, U, and Zr) mainly originated in parent rocks. Another group (Cr, Ni, Sr, and V) was mainly supplied by industrial plants and traffic emissions. The third group (Ba, Co, Cu, Mn, Pb, and Zn) was mainly supplied through pyrite ore exploitation processes. (3) Some samples were slightly to moderately polluted with Cs, Ga, Ge, Nb, Rb, Ta, and Ti. Most samples were moderately to highly polluted with Ba, Co, Cu, Mn, Pb, and Zn. (4) Trace elements in soil pose strong non-carcinogenic and carcinogenic health risks to people (particularly children) living near the Yunfu pyrite mine. [ABSTRACT FROM AUTHOR]

The aims of this study were to investigate the occurrence and distribution of total mercury (Hg) and other trace elements of environmental concern, such as arsenic (As), copper (Cu), chromium (Cr), manganese (Mn), nickel (Ni), lead (Pb), zinc (Zn) and vanadium (V), in soils from the abandoned Merník cinnabar mine in eastern Slovakia. For this purpose, thirty soil samples from two depth intervals within the mine area (n = 60 soil samples) and additional sixteen soil samples from adjacent areas (n = 25 soil samples) were collected. Total Hg was measured by atomic absorption spectrometry, while As and other metals were analyzed using inductively coupled plasma atomic emission spectrometry. High mercury concentrations (> 100 mg/kg with a maximum of 951 mg/kg) were observed only in surface soils close to mine waste heaps and adits. Otherwise, Hg concentrations in the majority of surface soils were lower (0.14–19.7 mg/kg), however, higher than Hg in soils collected from sites outside the mine area (0.19–6.92 mg/kg) and even considerably higher than Hg in soils at sites not influenced by the Merník mine. Elevated Cr and Ni concentrations in soils regardless of their sampling sites (mean of 276 mg/kg and median of 132 mg/kg for Cr and 168 mg/kg and 81 mg/kg for Ni, respectively) were attributed to the lithology of the area; the soils are underlain by the sediments of the Central Carpathian Palaeogene, containing a detritus of ultrabasic rocks. As our geochemical data are compositional in nature, they were further treated by compositional data analysis (CoDA). Robust principal component analysis (RPCA) applied on centred (clr) log-ratio-transformed data and correlation analysis of compositional parts based on symmetric balances distinguished very well different sources of origin for the chemical elements. The following three element associations were identified: Hg association with the main source in mining/roasting, Cr–Ni association derived from bedrock and As–Cu–Mn–Pb–Zn–V association (natural background and minor sulphides/sulfosalts in mineralized rocks). The values of geoaccumulation index and enrichment factor suggested that concentrations of Hg in the soils were influenced by human industrial activities. [ABSTRACT FROM AUTHOR]

This study reports the contents and sources of Cu, Hg, Cr, Ni, Co, Zn, Pb, Cd, As, and B pollution in soil samples from Srem in the province of Vojvodina (Republic of Serbia). They are collected in the vicinity of local industrial facilities. The main objective of this study is evaluating the impact of the industrial facilities on the eventual contamination of soils used mostly for agricultural manufacturing. This paper describes the implementation of the combination of methods to estimate the ecological status and determine potential ecological risk. This study applies sequential extraction, pollution indices, comparison with the guidelines, and statistical analysis. Other soil parameters, such as organic matter content, pH, and clay content were measured to evaluate their influence on the trace element content. The investigated soil samples exhibited the raised contents of Ni, Hg, and Cu. Elevated contents of toxic elements observed in localities accommodated within an impact zone affected by industrial complexes, indicating a correlation between the contamination of surrounding soil and potential impact on plants. The most mobile elements are Hg, Cd, and B, while Cr is the least mobile and potential least bioavailable. The results indicate Cr and Ni content increase marking the presence of bedrock, notably in the area of underlying ultramafic rocks and the surface zones influenced by diluvial-proluvial and alluvial processes. The second source of Cr and Ni in the soils of Srem is industrial activities such as leather, cement industry, as well as the metal processing factory. [ABSTRACT FROM AUTHOR]

The legal regulatory/action levels of trace elements in soils are established at high concentrations, at which the crucial functions of soil are at risk or are eliminated. However, concentrations below these action levels, but above presumed natural levels, may also limit particular ecosystem services, including organic food production. Thus, defining the (ambient) background concentrations is an essential part of environmental or health risk assessment, e.g., on Chernozems, which are considered to be the most productive soils and ones that should be protected against all forms of contamination. Based on 28 profiles of chernozemic soils developed from loess in an agricultural region of SW Poland presumed to be free of industrial contamination, ambient geochemical baselines have been derived for Fe and six trace metals for four standardized soil layers, including the topsoil (plow layer) and parent material layers. The median values for the plow layer (1.89% for Fe, and 537, 49, 17, 14, and 26 mg kg−1 for Mn, Zn, Pb, Cu, and Ni, respectively) are lower than the values reported for other Chernozems in SE Poland/Europe/the world, and thus may serve as a general geochemical baseline for chernozemic soils developed from loess. The concentration of Cd, although lower than in other Chernozems around the world, is higher than in Ukrainian Chernozems and thus may serve as a local (or Central European) baseline only. The median concentrations of Fe, Cu, Mn, and Zn are very close to their concentrations in the Chernozem buried under the Neolithic kurgan. However, Pb and Cd concentrations are two times higher than in the buried soil, indicating the scale of general contamination of the topsoil horizons of arable soils. Concentrations of the elements under study, excluding Fe, in both the buried and surface soils are significantly higher in the topsoil layer compared to parent material (loess), and this justifies the separate baseline values for topsoil horizons, instead of background values derived universally for parent rock types. This is essential, in particular in soils texturally differentiated within profiles, where the subsoil material has a different origin and cannot be considered the parent material for topsoil horizons. Underlying or locally outcropped bedrock (e.g., serpentinite rocks) may naturally enhance the total concentration of trace elements in the entire soil profile by the addition of metal-rich regolith particles during the formation of surface covers, e.g., by eolian processes under periglacial conditions (Late Pleistocene). Such soils are naturally enriched with metals (with nickel in the case of serpentinite bedrock), cannot be considered contaminated, and thus require a separate legal treatment, including separate (or individually suited) background baselines for health risk assessments. [ABSTRACT FROM AUTHOR]

This paper presents the results of the preliminary testing of the selected trace elements in the soils of several parks in the city of Zagreb, Republic of Croatia. In each park, the samples were taken from several points—at various distances from the roads. The samples were taken at two different depths: 0-5 and 30-45 cm. Composite samples were done for each sampling point. Microwave-assisted wet digestion of the soil samples was performed and the determination by ICP-AES technique was done. Results obtained for Al, As, Ba, Mn, Ti, V, and K are in a good agreement with the results published in the scientific literature so far. The mass fraction values of Cd, Cr, Cu, Ni, Pb, and Zn are somewhat higher than the maximum values given in the Croatian Directive on agricultural land protection against pollution. Be, Mo, Sb, Se, and Tl in the samples were present in the concentrations that are lower than their method detection limit values. [ABSTRACT FROM AUTHOR]