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Generally, pesticides are the products containing at least one chemical substance which should protect plant or plant products against pests/diseases. Among them, the most important ones are herbicides, followed by insecti-cides and fungicides. As a result of intensive agriculture techniques, large amounts of pesticides are applied on agricultural soil. They remain and degrade in soil, but they can enter water bodies and negatively affect water quality and the aquatic ecosystem. The article deals with the level of pesticide load in soil, bottom sediment and surface water in chosen agriculture catchments in the Czech Republic. Results revealed that the main general problem is glyphosate and its metabolite AMPA, although their application has been constrained for several years. Furthermore, the difference in contents of chosen parent pesticide substances and their metabolites in soils and waters were pointed out.

In this paper we address total glomalin-related soil protein (T-GRSP) as a possible indicator of differences in forest soils related to reactive nitrogen and forest composition. We focused especially on the relationship between T-GRSP (g kg(-1)), soil organic carbon (SOC), and reactive nitrogen (N-r) availability among different categories of temperate forests and different horizons. Our study included 105 sampling sites divided into 5 categories, which vary in elevation and tree species composition (coniferous, deciduous, mixed). We detected significantly higher T-GRSP and SOC in the F+H horizon under conifers. We assume that this observation might be attributed to suppression of decomposition of T-GRSP and SOC by nature of coniferous litter. We found a significantly higher content of T-GRSP in the F+H horizon for all studied forest categories. However, the contribution of T-GRSP to SOC is significantly higher in the Ahorizon, which might be caused by stabilization of glomalin by mineral fraction, including clay minerals or by the belowground origin of glomalin. We found the increase of SOC with increasing N-r in the Ahorizon for most categories of forest. T-GRSP follows this trend in the case of deciduous forests (decid), mixed forest (mixed), and mountain forests (mount). On the other hand, we detected a decrease of T-GRSP with increasing N-r in the F+H horizon of coniferous forests (conif). The T-GRSP/SOC decreases with the increase of N-r in the Ahorizon of conif, mixed and mount, which points to the higher sensitivity of forest with prevalence of coniferous trees. Our observations have confirmed an ecosystem-specific relationship between T-GRSP, SOC and N-r. We concluded that T-GRSP in combination with T-GRSP/SOC has the potential to reveal qualitative changes in soil organic matter (SOM) connected with increasing N-r.

Retention of four selected risk elements (SRE)-arsen (As), cadmium (Cd), lead (Pb), zinc (Zn)-by manganese (Mn) and iron (Fe) oxides in different forest soils was investigated. The abundance of oxides and the association between oxides and SRE were observed in 91 soil samples of different forests divided into 5 categories covering the variability of forests in the Czech Republic. The sequential extraction procedure was used for dissolution of Mn and Fe oxide fractions (MnOF and FeOF) separately and together with the associated elements. It was found that Mn associated with MnOF is significantly higher in deciduous forests. These differences were ascribed mainly to the higher pH and lower DOC (dissolved organic carbon) in deciduous forests. The association of SRE with MnOF declines in the order Cd >> Pb > Zn > As and the association with FeOF in the order As approximate to Pb >> Cd > Zn. Despite their relatively lesser occurrence, MnOFs were found to be very significant for retention of Cd. FeOF is strongly associated with As and Pb. The category of forest has been identified to influence the amount of SRE retained by oxides especially in two cases: (1) the category of forests on Fluvisols differs from the other categories; (2) the retention of Cd by MnOF or FeOF is larger in deciduous forests compared with coniferous forests.

Extensive soil sampling and screening assessment of ecosystem risks combined with a multidimensional statistical analysis were used to estimate and spatially characterize the ecosystem risks stemming from the contamination of floodplain soils in the Czech Republic. We proved structural differences in regional pollution patterns where different regional/local pollution sources led to various nature and extent of the environmental load of floodplain soils. The established spatial patterns helped reveal the areas where soils do not meet soil quality standards and where the ecosystem risks were elevated. Furthermore, the results allowed to establish priority contaminants of flood affected areas in various catchments in the Czech Republic. Combining both the magnitudes of estimated ecosystem risks and structural characteristics of pollution profiles, the highest estimated risks showed the localities with high contents of organochlorine pesticides, several samples connected to geochemical anomalies of metallogenic zones (deposits), and localities with a long history of industrial load. Since extreme weather events have recently become more frequent, our results highlight the importance of a continual monitoring of pollutant turnover in floodplain soils with a high flood frequency.

The purpose of the presented study was to identify possible ecological and health risks by metal contamination in soil. More than 50,000 topsoil samples in agricultural soil were used to evaluate spatial concentrations and risks posed by selected metals on a national scale. Variograms and correlograms were used to identify metal spatial patterns and appropriate sampling distances. All metals were spatially dependent on short distances (up to 7 km). Optimal sampling densities to detect contamination at the local scale were estimated to be at around 1 sample per 0.5 km for Cd, Cu and Zn and 1.5–2 km for Pb, Hg and Ni based on Moran's index = 0.7. The concentrations of metals were partly influenced by precipitation and pH, but mostly by geology and industry. The Kriging method was used to create interpolated maps for individual metals. High concentrations of Cd, Pb and Zn were found in well-known mining areas (the Ore Mountains, the Upper Silesian Basin, the towns of Kutna Hora and Přibram). Elevated Ni and Hg concentrations resulted mainly from the nature of the parent rock material. Cu contamination was specifically influenced by Cu-based fungicides applied on soils where hop and wine are grown. Czech and European legal limits for various pH and soil textures were applied to identify potential risk areas. A relatively large area of agricultural soil (16%) is above the prevention limit for at least one metal. However, only a few localities exceed the limits with respect to food chain contamination and the inhibition of plant growth. Comparison of our results with European studies (LUCAS, GEMAS, FOREGS) points to the need for high density sampling in order to conduct accurate risk assessment and demonstrates that serious soil contamination happens (and needs monitoring) at the local and not the continental scale.

Although large amounts of pesticides are used annually and a majority enters the soil to form short- or long-term residues, extensive soil surveys for currently used pesticides (CUPs) are scarce. To determine the status of CUPs' occurrence in arable land in Central Europe, 51 CUPs and 9 transformation products (TPs) were analysed in 75 arable soils in the Czech Republic (CR) several months after the last pesticide application. Moreover, two banned triazines (simazine and atrazine) and their TPs were analysed because of their frequent detection in CR waters. Multi-residue pesticide analysis on LC-MS/MS after soil QuEChERS extraction was used. The soils contained multiple pesticide residues frequently (e.g. 51% soils with ≥5 pesticides). The levels were also noticeable (e.g. 36% soils with ≥3 pesticides exceeding the threshold of 0.01mg/kg). After triazine herbicides (89% soils), conazole fungicides showed the second most frequent occurrence (73% soils) and also high levels (53% soils with total conazoles above 0.01mg/kg). Frequent occurrence was found also for chloroacetanilide TPs (25% of soils), fenpropidin (20%) and diflufenican (17%). With the exception of triazines' negative correlation to soil pH, no clear relationships were found between pesticide occurrence and soil properties. Association of simazine TPs with terbuthylazine and its target crops proved the frequent residues of this banned compound originate from terbuthylazine impurities. In contrast, frequent atrazine-2-hydroxy residue is probably a legacy of high atrazine usage in the past. The occurrence and levels of compounds were closely associated with their solubility, hydrophobicity and half-life. The results showed links to CR water-monitoring findings. This study represents the first extensive survey of multiple pesticide residues in Central European arable soils, including an insight into their relationships to site and pesticide properties.

The proposal of hierarchical limit system of risk elements (RE) and persistent organic pollutants (POPs) for agricul tural soils is presented. The system is not proposed for forest soils (limits are still missing in the Czech Republic). Two levels of limit values were proposed. The first one is the prevention limit statistically derived from the back ground values of RE and POPs in Czech agricultural soils. The second one is indication limit derived from the risk of plant growth inhibition (RE phytotoxicity effects where the results of experimental trials were utilised), the risk of food chain contamination (RE transfer from the soil into the plants where the results of experimental trials testing the transfer of RE from soils into plants were used) and human health risks (RE and POPs inhalation, dermal and oral intake where the model following US EPA methodology was calculated). The limit values system should replace current version of legislative norm – Decree No. 13/1994 Coll. The principles of limit values assessment for individual levels of the limits are described.

The subject of this study is the assessment of the influence of climate and land use change on the potential re-emission of organochlorine pesticides (OCPs) from background and agricultural soils. A deterministic spatially and temporally explicit model of the air-surface exchange was created, fed with distributed data of soil and atmospheric concentrations from real measurements, and run under various scenarios of temperature and land use change for a case study area representative of central European conditions. To describe land use influence, some important features were implemented including effect of plowing, influence of land cover, temperature of soil, and seasonal changes of air layer stability. Results show that volatilization of pesticides from soil largely exceeded dry gas deposition in most of the area. Agricultural soils accounted for more than 90% of the total re-emissions both because of the generally higher soil fugacities (higher loads of chemicals and relatively low organic carbon content), but also due to physical characteristics and land management practices enhancing the dynamics of the exchange. An increase of 1 °C in air temperature produced an increase of 8% in the averaged total volatilization flux, however this effect can be neutralized by a change of land use of 10% of the arable lands to grassland or forest, which is consistent with projected land use change in Europe. This suggests that future assessment of climate impact on POP fate and distribution should take into consideration land use aspects.

The upper values of the extractability of trace elements (As, Be, Cd, Co, Cr, Cu, Ni, Pb and Zn) in 2 mol/L HNO3 and 0.025 mol/L ethylenediaminetetraacetic acid (EDTA) (compared with their pseudototal content in aqua regia) for determination of prevailing anthropogenic and geogenic soil load were proposed and compared with the results of the other 30 Fluvisol samples collected from the Labe fluvial zone. The increased geogenic load of Fluvisols was confirmed in the case of Be and As in some localities where low extractability with increased pseudototal contents were detected as opposed to the other elements when their increased pseudototal contents were followed by their increased extractability. The maps of probability of increased geogenic soil load in the area of the Czech Republic based on the comparison of geological substrates and trace element load were constructed. The combination of proposed elements extractability values for geogenic load together with developed maps is a suitable tool for the definition of prevailing Fluvisol or sediment load on some localities in the whole area of the Czech Republic. The results can be also a useful tool in the decision making processes regarding dredged sediment application on agricultural soil (support tool for legislative norms, Direction No. 257/2009 Sb.).

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. 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). 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. 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.

A new system of soil contamination limit values proposed for Czech legislation is described. The system is based on the hierarchical limit values system with two levels. The first one—prevention limit—defined background values of risk lements (REs) and persistent organic pollutants (POPs) in Czech agricultural soils supported by the data from soil monitoring system. The second one—indication limit—is defined for human health protection by two principles, the protection of food chain and the protection of direct human health risks by inhalation, dermal and oral intake of RE and POPs in soil particles on the field. The practical application of limit values proposal was applied in the roject focused on soil contamination influence on health and environmental risks in fluvial zones of Czech important river basins. The floodplain soils belong to the most contaminated soils in Europe generally and the project defined the potential fluvial areas with increased human health risks.

Concentrations of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), and polybrominated diphenyl ethers (PBDEs) in air and soil, their fugacities, and the experimental soil-air partitioning coefficient (KSA) were determined at two background sites in the Gt. Hungarian Plain in August 2013. The concentrations of the semivolatile organic compounds (SOCs) in the soil were not correlated with the organic carbon content but with two indirect parameters of mineralization and aromaticity, suggesting that soil organic matter quality is an important parameter affecting the sorption of SOCs onto soils. Predictions based on the assumption that absorption is the dominant process were in good agreement with the measurements for PAHs, OCPs, and the low chlorinated PCBs. In general, soils were found to be a source of PAHs, high chlorinated PCBs, the majority of OCPs and PBDEs, and a sink for the low chlorinated PCBs and γ-hexachlorocyclohexane. Diurnal variations in the direction of the soil-air exchange were found for two compounds (i.e., pentachlorobenzene and p,p'-dichlorodiphenyldichloroethane), with volatilization during the day and deposition in the night. The concentrations of most SOCs in the near-ground atmosphere were dominated by revolatilization from the soil.

The sediment characteristics (pH, CEC, Al-exchangeable, Cox, humus substances), the content of potentially toxic elements and persistent organic pollutants were analysed in the sediments and compared between sediment groups. The comparison of sediment contamination with Czech legislation for sediment use in agriculture was conducted. The village sediments were more loaded by potentially toxic elements and persistent organic pollutants than the others. The pH value of sediments was considered as the properties regulating the retention of potentially toxic elements and their mobility (Al, Cd, Zn). Polycyclic aromatic hydrocarbons (PAHs) were the most problematic POPs group in the sediments. The correlation showed poor dependency of POPs (especially PAHs) content on the content and quality of sediment organic matter.

A total number of 471 soil samples collected during the period of 1996-2006 from the agricultural and forest areas of the Czech Republic were analyzed for their content of persistent organic pollutants (POPs). Spatial variability of the POP concentrations was assessed using an IDW spatial GIS model analysis. For every grid of the network, resulting modeled levels of contamination allowed for estimation of the total burden of POPs in soils. Potential risks associated with contaminated soils were assessed as well. Database of the old ecological burdens counting 3061 sampling sites was used to adjust the model and incorporate the risks of heavily contaminated sites. The high levels of health risks were only found at less than 1% of the area of interest. The IDW modeling proved to be a useful tool for screening of the health risks in the large areas with scarce monitoring data. Presented approach can be applied in the risk management, to support an efficient targeting of the risk reduction measures, or to improve a design of the national monitoring.

Good quality data apt for an assessment of temporal trends of polychlorinated dibenzo-p-dioxins and furans (PCDDs/Fs) in soils are difficult to obtain since there is a general lack of information on their residues in soils. Variability of soil profiles, non-homogeneity of samples, and often also inconsistency of applied sampling procedures further complicate this problem. To assess spatial and temporal trends of contamination, three soil sampling campaigns have been performed over the period of 12 years at the mountain forest sites in the Czech Republic. Relation between the air, needle and soil contaminations was addressed in addition to time-related variability of soil. It has been confirmed that soil is a good matrix for evaluation of spatial distribution of persistent organic pollutants (POPs) but difficult for establishment of temporal trends. A slow rate of the soil-forming processes and their site-specificity was generally the major source of uncertainties.

Background concentrations of selected persistent organic pollutants (polychlorinated biphenyls, hexachlorobenzene, p,p'-DDT including metabolites) and polyaromatic hydrocarbons in soils of the Czech Republic were predicted in this study, and the main factors affecting their geographical distribution were identified. A database containing POP concentrations in 534 soil samples and the set of specific environmental predictors were used for development of a model based on regression trees. Selected predictors addressed specific conditions affecting a behavior of the individual groups of pollutants: a presence of primary and secondary sources, density of human settlement, geographical characteristics and climatic conditions, land use, land cover, and soil properties. The model explained a high portion of variability in relationship between the soil concentrations of selected organic pollutants and available predictors. A tree for hexachlorobenzene was the most successful with 76.2% of explained variability, followed by trees for polyaromatic hydrocarbons (71%), polychlorinated biphenyls (68.6%), and p,p'-DDT and metabolites (65.4%). The validation results confirmed that the model is stable, general and useful for prediction. The stochastic model applied in this study seems to be a promising tool capable of predicting the environmental distribution of organic pollutants.

Detailed soil screening data from the Czech Republic as a typical Central European country are presented here. Determination of a wide selection of organic and inorganic pollutants as well as an assessment of specific soil parameters allowed us to study the soil contamination in relation to the land use and soil properties. While HCHs and HCB were found at highest levels in arable soils, the higher concentrations of PCDDs/Fs, PCBs, PAHs and DDTs were observed in high altitude forest soils. Concentrations of these compounds strongly correlated with the soil organic carbon content. Several possible reasons have been suggested for the observed higher concentrations in mountain forest soils but the impact of each of these influencing factors remains to be identified. An inventory of the soil contamination is needed as a first step in our effort to estimate an extent to which the secondary sources contribute to the enhanced atmospheric levels of POPs.

In this study, the effects of road salting on the quality of forest soils near the road were monitored in the Krkonose Mountains (Czech Republic). Physical, chemical properties and microbial parameters of soils were determined and the toxic potentials of soil water extracts were evaluated using the bacterial tests (Microtox and Pseudomonas putida growth inhibition test). Increased concentrations of Na+ ions (up to 100 mg/kg) and PH values up to 8 were found closer to the road. Microbial biomass and respiration activity were significantly reduced at the roadside (ANOVA; P < 0.05), and the metabolic quotients showed that the microbial community was apparently under stress. Large stimulation of Pseudomonas putida growth was determined, especially for salinized samples closest to the road. Oppositely, results showed the unsuitability of bacteria toxicity tests in such cases of pollution. Assessment of intrinsic soil microbial communities is more ecologically relevant and shows the effects that cannot be detected by bacterial toxicity tests.

The aim of this study was to compare the pollution levels of risk elements in flooded and non- flooded alluvial soils as a function of inundation fre- quency and river distance, depth of soil horizon, and pollution origin. Totally, 43 soil profiles of flooded and non-flooded soils were sampled in two layers (topsoil and subsoil). The total contents of As, Cd, Co, Cr, Cu, Mo, Ni, Pb, V, and Zn were measured and grouped according to the assumed geogenic or anthropogenic origin. Flooded soils were classified according to inun- dation stage/river distance. Concerning the depth gradi- ent, it can be concluded that the content of anthropo- genic risk elements decreased with the depth, while geogenic risk elements revealed no trend. The distance from the river had no influence on the distribution of anthropogenic risk elements in soil. On the contrary, geogenic risk elements showed increasing concentra- tions with increasing distance. These results indicate that frequency of floods has no influence on the risk elements distribution in soil. The process of sedimenta- tion seems to be the main factor influencing the level of pollution, it differs between groups of anthropogenic and geogenic risk elements. The result of this country- wide study shows higher levels of soil contamination in flooded areas even without significant point sources of pollution, than in non-flooded areas in standard agricul- tural conditions.

Thallium (Tl) and its compounds are toxic to all organisms. Relatively high levels of thallium of pedogeochemical origin have been found in some areas of the Czech Republic. The contents of >2 mg kg−1 of Tl have been found in aqua regia soil extracts of soils originated from melanocratic porphyric hornblende-biotite granite or from hornblende-biotite granodiorite. The contents of Tl in the range of 0.45–1 mg kg−1 have occurred mainly in soils originated from paragneiss. A detailed study of some of these sites has been made. Content of thallium in soils was determined after extraction with aqua regia, 2 M HNO3, DTPA-TEA and 1 M NH4NO3. Plant samples (whole rapeseed kernels) were wet ashed and the total content of Tl was determined. The amount of Tl in soils extracted by the different extracting methods in comparison to aqua regia (100%) was approximately 14% for 2 M HNO3, 0.8% for 1 M NH4NO3 and only about 0.03% for DTPA-TEA. The content of Tl in the rapeseeds was approximately 75% of this element determin...

Part 5: Information Tools for Global Environmental Assessment; International audience; The goal of this study was to use the modeling tools for prediction of environmental concentrations and pools of pesticides (HCB and DDT) in soil. The characterization and quantification of secondary background sources of HCB, were computed using fugacity based deterministic model. Areas with a high potential for deposition and volatilization of HCB were identified. Results of modeling were maps showing spatial distribution of HCB and DDT in the Czech Republic which have been visualized on the web portal GENASIS (Global Environmental Assessment Information System) to provide information on environment contamination.