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The microstructural, physical, and sensory properties of low-fat sauces made with different rice starches, soy protein ,and inulin were analysed in order to obtain sauces suitable for celiac and lactose intolerant consumers. Soy protein and inulin could prevent starch degradation due to their high water-binding capacity. Moreover, protein molecules could diffuse into the starch granules and soluble inulin could interact with starch polymers within the granule. Both effects would hinder amylose leaching. Inulin provides better diffusion capacity of gelatinised granules and soy protein-starch granule aggregates than sunflower oil, which helps to decrease viscosity in modified rice starch sauces. Soy protein prevents syneresis in the sauces. Inulin affects colour parameters in native rice starch sauces, probably because of inulin and retrograded amylose polymers interactions. Sauces made with sunflower oil and modified rice starch are best rated by consumers. However, according to the statistical analyses, the replacement of oil by inulin could be suitable to prepare low-fat, gluten, and lactose free white sauces when modified rice starch is used.

The disulfide bonds and sulfhydryl in gluten were evaluated to investigate the effects of structural characteristics on the quality of white noodles. The free sulfhydryl concentration increased significantly, but disulphide bonds decreased initially, and then became stable with increasing sodium sulfite concentration. With a decrease in disulfide bond concentration from 56.78 μmol/g to 20.01 μmol/g in gluten added to noodles, microstructural graphs verified that the cross-section and surface of noodles became rougher and looser with more holes generated; optimal cooking time decreased from 4.4 min to 3.3 min for fresh noodles and from 10.11 min to 9.19 min for dried samples; water absorption and cooking loss increased from 159% to 203% and from 5.26% to 9.06%, respectively. A decreasing trend and marked differences were observed for hardness, springiness, chewiness as well as resilience of fresh and cooked noodles, but the cohesiveness of fresh noodles exhibited no significant changes (P < 0.05).

The cells of commercial strain Bifidobacterium animalis subsp. lactis Bb12 were encapsulated using emulsion encapsulation in a milk protein matrix. The volume based median of the microcapsules was 52.1 ± 6.2 µm. The stability of free and encapsulated cells was compared during 28 day-storage in pineapple juice and in strawberry-apple juice at 8 ± 1°C and 22 ± 1°C. Encapsulation ensured a higher number of cells compared to the free cells only at 8 ± 1°C. Strawberry-apple juice was found to be not suitable as probiotic vehicle. Both free and encapsulated cells lost their viability after 14 days at 22 ± 1°C. The number of bifidobacteria cells, pH and lactic and acetic acid content did not change in pineapple and strawberry-apple juice after 24 h cultivation at 37°C.

The uncontrolled release of arachidonic acid (ARA) and its metabolism by lipoxygenase (LOX) pathway can induce and aggravate cellular oxidative stress. Selenium (Se) is an integral part of some antioxidative selenoproteins and may protect cells from oxidative damage by modulating ARA release and metabolism. The present study aimed to investigate the protective response of Se against hydrogen peroxide (H₂O₂)-induced oxidative damage in bovine mammary epithelial cells (BMECs). The BMECs were incubated for 24 h in serum-free medium and then divided into four groups randomly. The cells in groups 1 and 2 were subsequently incubated for 30 h in serum-free medium containing 0 (control) and 50 nM Se (Se treatment group). The cells in groups 3 and 4 were incubated for 24 h in serum-free medium containing 0 and 50 nM Se, and then treated with 600 μM H₂O₂ for 6 h (H₂O₂ damage group and Se prevention group). The results showed that Se attenuated the H₂O₂-induced production of reactive oxygen species and the decrease of antioxidative enzymes as glutathione peroxidase (GPX), thioredoxin reductase (TrxR), selenoprotein P (SelP), superoxide dismutase, and catalase in BMECs. The preventive effects of Se on the decrease of selenoprotein activity were demonstrated further by the increase of mRNA expression for GPX1, TrxR1, and SelP, and protein expression for GPX1 and TrxR1. Pretreatment of cells with Se inhibited the H₂O₂-induced increase of mRNA expressions and activities for cytosolic phospholipase A2 and 5-lipoxygenase, ARA release, and 15-hydroperoxyeicosatetraenoic acid production. Se also blocked the H₂O₂-induced activation of p38 mitogen-activated protein kinase (MAPK) and c-Jun N-terminal kinase but not that of extracellular signal-regulated kinase. These results suggested that Se may protect BMECs against H₂O₂-induced oxidative damage by increasing selenoproteins synthesis, inhibiting MAPK pathway, and then decreasing ARA release and its metabolism by LOX pathway.

Evidence shows that oxidative stress associated with sperm cryopreservation may lead to a significant decrease of the structural integrity and functional activity of male gametes. Curcumin (CUR) has become a substance of scientific interest for its free radical-quenching abilities, which could enhance the post-thaw quality of male gametes. This study assessed the effects of CUR on the post-thaw vitality and selected oxidative stress markers of bovine spermatozoa. Thirty ejaculates collected from 10 breeding bulls were divided into two aliquots and cryopreserved in the absence (control) or presence of CUR (50 μmol/l). Immediately before use, the control or experimental straws were thawed at 37°C for 20 s. CUR administration led to a significantly higher preservation of spermatozoa motion (P < 0.001) as well as membrane (P < 0.05) and acrosomal (P < 0.01) integrity in comparison with the control. Moreover, spermatozoa exposed to CUR exhibited a significantly higher mitochondrial activity (P < 0.001). Significantly decreased amounts of reactive oxygen species (P < 0.01) and superoxide (P < 0.001) were detected following CUR supplementation. Finally, a significant decrease of oxidative damage to proteins (P < 0.01), lipids (P < 0.001), and DNA (P < 0.05) was recorded in samples to which CUR was administered in comparison to the control. In this study, CUR proved to act as an efficient antioxidant molecule offering protection to male gametes against oxidative damage during cryopreservation.

Wood ash production from power plants and the use of recycled ash for earthworks and forest peatland fertilization have increased markedly in Finland in recent decades. In this study, effects of wood-based ash on potted Scots pine seedlings were tested in a greenhouse. Seedlings were grown for one to two growing periods in peat with ash mulch thicknesses 0-8 cm. Seedlings grew well in ash thicknesses 0-4 cm during the first growing period. Seedling mortality (60%) occurred with the thickest ash mulch. Soluble nutrients in press water extracts were high compared with the control treatment. N and P levels were suboptimal also with ash mulch. During the second growing period, seedling mortality occurred (17%) already with the thinnest ash mulch. The results suggest that ash mulch around seedlings in quantities of less than 0.5 cm (or 7 kg.m^-2) is feasible and is not detrimental to Scots pine seedlings. The results provide foundation for further field research on the longer-term impacts of wood ash mulch on planted seedlings on boreal forest sites and on the feasibility testing of the mulch as a supplement to or substitute for the soil preparation for seedling planting.

The article analyses growth and quality of Northern red oak (Quercus rubra Linnaeus) based on 13 research plots (seven in red oak stands and six in sessile oak stands) with the ages between 17 to 159 years. The collected data includes height, DBH, crown diameter, stem and crown quality, health status of each tree on the plot. Analogous plots were chosen in sessile oak (Quercus sessilis Linnaeus) stands on similar sites to get reference data. The results proved the high wood production potential of red oak when compared to sessile oak being at the same or higher quality and health. The data propose the red oak to be a good additional species in lowland stands.

The aim of the present study was to develop allometric equations for predicting aboveground biomass of Norway spruce (Picea abies (Linnaeus) H. Karsten) applicable to the typically managed spruce forest on acidic and nutrient-medium sites in the Czech Republic. The models were based on an extensive data set of 139 spruce trees collected in 25 stands on 15 sites. The biomass in dry mass was modelled using linear regression equations with one (diameter at breast height - D), two (D, slenderness ratio - H/D) or three (D, H/D, site index - SI, or tree age - A) predictors. The models were validated using the leave-one-out method. The value of the root mean square error of cross-validation was chosen as the main criterion for the best-model selection. Both the total aboveground biomass and stem biomass were best predicted by three-variable models (D, H/D, SI). For crown and foliage biomass the simple one-variable model (D) is recommended.

The Scots pine (Pinus sylvestris Linnaeus) is one of the most important commercial tree species in Central Europe, yet we know very little about the variability of its wood properties. The aim of this study is to primarily analyse the impact of different tree growth rates and site characteristics on the shrinkage of Scots pine wood. The investigated forest stands are located at two sites of the Czech Republic that are characteristic for Scots pine silviculture. At each site, sample trees were selected from two stands representing two variants of the silvicultural treatment, i.e. a clear-cutting and shelterwood system with long regeneration period. Wood shrinkage in radial and tangential directions and volumetric shrinkage were determined in accordance with Czech standards. Lower values of shrinkage were found out in forest stands regenerated by the shelterwood method. The wood in the central part of the trunk shows lower shrinkage values than in the basal part in both stands. The unambiguous effect of the horizontal position in the trunk stem was demonstrated in forest stands regenerated by the clear-cutting method, whilst stands regenerated by the shelterwood method showed a more even distribution of shrinkage along the trunk width. Furthermore, it was found that the shrinkage of the Scots pine has a medium dependence on wood density.

The study was carried out in the experiment with 16 provenances of common ash (Fraxinus excelsior Linnaeus) and 2 provenances of narrow-leaved ash (Fraxinus angustifolia Vahl) at a series of 5 parallel trial plots established in a gradient from lowland riverine to upland ravine sites. The role of the site, ash species and the provenance of common ash proved to have significant effects on the intensity of ash dieback (ADB) associated with the infection by Hymenoscyphus fraxineus (T. Kowalski) Baral, Queloz & Hosoya at the age of 20 years. Narrow-leaved ash was healthier, surviving and growing better than common ash on the trials situated inside as well as beyond its natural range. The ADB intensity was lower in the medium altitude and more easterly located trial plots with a more continental climate. The provenance of forest reproductive material proved to have a significant effect on the ADB damage and survival rate as well as the growth of ash across the trial plots of the experiment.

Three sites including "less disturbed", "moderately disturbed" and "severely disturbed" were selected in Zagros forests in Kurdistan province (Iran). Three forest stands with similar physiographic conditions of each site were selected and three 400 m2 plots were assessed in each stand to record the floristic information and soil sample (0-30 cm). Different diversity indices were calculated for each sample. Cluster analysis and to collect soil samples detrended correspondence analysis were applied to categorize and investigate the vegetation trend. Indicator species analysis was used to determine the characteristic species. Tukey test was used to compare the variables amongst sites. The results showed that 47, 25, 15 species were exclusively observed in less disturbed, moderately disturbed and severely disturbed sites, respectively. Furthermore, cluster analysis illustrated the distinction amongst sites and detrended correspondence analysis result showed that the vegetation of the regions was ordinated by disturbance gradient. 21, 5, 7 characteristic species were respectively indicated in less disturbed, moderately disturbed and severely disturbed sites. In general, plant composition, plant diversity and soil quality were decreased dramatically along the disturbance gradient.

In order to increase productivity, sustainability and protection of the 5-year-old beech plantations of the Greater Caucasus northeastern slopes, 10 plots were established in large gaps and glades of four quarters of the Quba and Qusar forestry. Silvicultural treatments which were realized based on sowing and planting methods or applying both of them in a combined form were carried in this region. The sowing operations were carried out on sites of 1 × 1 m and 1 × 2 m in size and using an amount of 120-300 individuals per hectare, located across the slope. The best results in sowing sites in terms of the number of emerging beech seedlings and their survival were obtained in fresh herbage, and the worst in moist herbage forest growing conditions. In the stands created by planting, in fresh herbage forest growing conditions the best results were obtained in the middle mountain belt and satisfactory in the high mountain belt. Cultivated plants 6-8 years after sowing (planting) were transferred to a forest covered area. During this time, in the plants were carried out: with sowing - 10 treatments, with planting - 5 agrotechnical treatments.

This paper presents the first comprehensive checklist of vascular plants for an especially important area for biodiversity, namely National Park "Ethnikos Drymos Oitis" - Natura 2000 site (GR2440004) and the surrounding area in Greece. This list includes a total of 1,153 plant taxa, including 79 endemic taxa and two local endemic species (Allium lagarophyllum Brullo, Pavone & Tzanoudakis and Veronica oetaea Gustavsson). It is noteworthy that 551 plants are new records for the flora of Mt. Oiti. A total of 67 taxa are protected by national and international legislation, while 52 orchid taxa are also protected by the Convention of International Trade in Endangered Species of Wild Fauna and Flora (CITES). Veronica oetaea, a priority species of Annex II of the Directive 92/43, is also protected by the Berne Convention. The high plant species diversity and endemism make Mt. Oiti National Park an important area with high conservation value, thus providing baseline information which could be utilized for further research.

The paper analyses stand structure and production on two experimental forest stand series of mature pure and mixed Scots pine stands, growing on natural Scots pine sites in the Czech Republic. Sessile oak was the main admixed species. In mixed stands, Scots pine constituted the dominant level of the stand, admixed species grew mostly as subdominants. Admixture increased stand densities and aboveground biomass production compared to pure stands. Sessile oak with the 20-30% number share within the Scots pine stand led to an increase of the Scots pine tree dimensions and mean stem merchantable wood (DBH ≥ 7 cm) volume compared to the pure Scots pine stand of similar density. The Scots pine and sessile oak slenderness ratios increased in mixed stands compared to monocultures, however, the stand mechanical stability was not threatened.

The benefit of the entomopathogen Metarhizium anisopliae to early root development was evaluated. Two inoculating methods, conidia-suspension-drenching (T₁) and conidia-coating (T₂), were used when sowing peanut. The results showed that taproot length and lateral root number in T₁ significantly increased compared to the control (T₀) in days 4-10 after treatment, whereas no significant difference was found between T₂ and T₀. The fungal density by T₁ and T₂ fluctuated in the first 8 days, followed by a gradual decline. The ratio of the taproot length or lateral root number in T₁ and T₀ was significant relative to the fungal persistence. It suggested that M. anisopliae promotes peanut root development and should be considered as important factor in plant protection besides pest controls.

Changes of free amino acid (AA) contents (glutamic acid, glutamine, aspartic acid, asparagines, proline, hydroxyproline) in Noccaea caerulescens and Arabidopsis halleri under cadmium soil contamination (Cd1 = 30, Cd2 = 60, Cd3 = 90 mg/kg soil) are reported. Results of the pot experiment confirmed different effect of Cd on N. caerulescens in contrast to A. halleri and the higher stress adaptation of A. halleri. Total free AA contents in both plant species were not significantly modified by Cd contamination. The glutamic acid and glutamate contents in plant biomass were decreased under Cd2 and Cd3 stress. The declines of contents of both AA can be caused by intensive syntheses of plant defense elicitors, but declines in A. halleri were significantly lower in contrast to N. caerulescens. The content of aspartic acid was increased in N. caerulescens under Cd stress, but in A. halleri its changes were not observed. The different pathways of nitrogen utilization of tested plants were confirmed: the major AA forms used for nitrogen transport are glutamate for N. caerulescens and asparagine for A. halleri. The increase of proline content was determined only in N. caerulescens growing under Cd stress in the beginning of growing period.

For the purposes of assessment of long-term changes, two sets of Chernozems soil samples were analysed and compared in parallel: 'old' file samples obtained during the Soil Survey 1960-1970 in the former Czechoslovakia and a 'present' (2013) set of samples from exactly the same sites as the archive samples. The recently collected samples revealed worse qualitative parameters (lower humic acid to fulvic acid (HA/FA) ratios and higher colour quotient Q4/6 values) than the file samples, for all the localities. On the other side, the quantitative soil organic matter (SOM) parameters (oxidizable carbon (C_ox) and all its determined components) showed contrary results. The amount of total SOM at the same sites is higher now than it was about 50 years ago. It can be concluded that the current decline in SOM quality in Chernozems is partly compensated for by higher accumulation of SOM in the soils. All the analysed Chernozem samples were found to have much worse qualitative SOM parameters than the values mentioned for this soil type in the older literature. However, a comparison of the current data and the file data of Chernozem SOM quality can still be considered an open issue and require more complex research.

The influence of mineral fertilisers, liming, farmyard manure and sowing rate on the winter wheat grain yields was studied in a long-term field experiment at 4 sites under different soil and climatic conditions in the Czech Republic. A total of 135 partial fraction-factorial experiments were performed between 1980 and 2013 and evaluated using a statistical model with linear and quadratic terms for each factor. Yield trends demonstrated remarkable influence of fertilisation at two sites of lower starting productivity. Here, grain yields increased by 50% and 25% since the trial commencement, while the rate of yield increase was low at more productive sites. Yields were the most frequently influenced by nitrogen (N) fertilisation, uniformly at all sites. N response curves were strongly curvilinear, but these differed between sites and were affected by preceding crops. The relative frequency of statistically significant influences decreased in the following order: N (significant at α < 0.05 in 89% of all partial trials) > sowing rate (29%) > phosphorus (22%) > farmyard manure (15%) > potassium (12%) > liming (8%). This order and the frequencies of these influences are discussed with regard to relevant site and soil conditions.

Arbuscular mycorrhizal (AM) root colonization is known to have beneficial effects on plant growth especially under phosphorus (P) deficit conditions. The objectives of present study were: (i) to quantify changes in early wheat root development of AM-inoculated (AMI) and AM-free (AMF) roots under limited P availability; (ii) to assess possible mitigating effect of AM inoculation on photochemical efficiency under P deficit stress. AMI (inoculated with Rhizophagus irregularis) and AMF wheat plants were grown for 20 days in low (1 μmol/L) and high (50 μmol/L)P treatments. AM inoculation affected root morphology and shoot P concentration in low P treatment. AM inoculation alleviated reduction of the total root length in low P treatment, mainly due to an increase of fine roots length(< 0.5 mm). Contrastingly, shoot dry weight was reduced by AM inoculation in low P treatment. P deficiency decreased photochemical efficiency of wheat plants. However, due to increased sink capacity and facilitated nutrient concentrations AM inoculation alleviates phosphorus deficit stress and increased photochemical efficiency.

Field experiments were conducted at three sites: Yangling (YL); Zhouzhi-1 (ZH-1) and Zhouzhi-2 (ZH-2) of the Loess Plateau during summer maize crop, to investigate the effectiveness of N-(n-butyl) thiophosphoric triamide (NBPT) and NBPT + dicyandiamide (DCD) with urea on reducing NH₃ volatilization from different soils under different environmental conditions. Four treatments including control (no N), N-220 kg/ha, N-220 + NBPT and N-220 + NBPT + DCD were applied in two splits through the band placement method. Total NH₃-N loss observed were 65.8, 40.5 and 20.1 NH₃-N kg/ha (accounting for 29.9, 18.4 and 9.2% of N applied) from urea for YL, ZH-1 and ZH-2, respectively. The application of NBPT and NBPT + DCD significantly reduced NH₃ volatilization by 80-93% and 75-90%, respectively. The meteorologic factors such as precipitation, air temperature and wind speed significantly affected NH₃ volatilization. These results suggested that the amendment of urea with NBPT and NBPT + DCD have potential to mitigate NH₃-N losses from alkaline soils in the Loess Plateau.

The determination of a transport mechanism for genistin (genistein-7-O-glucoside) across the tonoplast was performed on vacuoles from a cell culture of Trifolium pratense L. Genistin levels were examined in vacuoles as well as in an assay medium by HPLC (high-performance liquid chromatography) after treatment with various substances. MgATP increased the uptake of added genistin by 25%, but the nucleotide-free samples also contained this glycoside. Applying bafilomycin A1, an H⁺-ATPase inhibitor, indistinctly inhibited genistin absorption. However, vacuolar absorption of genistin was significantly reduced by N,N´-dicyclohexylcarbodiimide. This inhibitor can suppress both H⁺-ATPase and H⁺-PPase; the effect of pyrophosphate alone was not investigated. An increase in genistein levels, as result of genistin hydrolysis, could also affect the transport mechanism. The results investigated with inhibitors suggest the possible involvement of proton pumps; however additional research is required to confirm the participation of multidrug and toxin extrusion (MATE) proteins in genistin transport.

A 5-year (2012-2016) field experiment was conducted to investigate the impacts of different fertilizer treatments (no fertilizer, mineral and organic fertilizer) on organic carbon and soil water-stable aggregates in a North China Plain Vertisol. Compared with no fertilizer (control), single mineral fertilizer did not significantly (P < 0.01) affect organic carbon content or aggregate mass proportion in bulk soil. Small and large macroaggregate mass proportions increased, but applying organic manure significantly decreased the silt + clay fraction and microaggregates. Organic manure amendment significantly enhanced organic carbon concentrations in aggregates (large macroaggregates, > 2000 μm; small macroaggregates, 2000-250 μm; microaggregates, 53-250 μm; and free silt + clay fraction, < 53 μm) and aggregate subfractions, including intraparticulate organic matter and silt + clay subfractions (< 53 μm). Single mineral fertilizer amendment increased organic carbon concentrations in macroaggregates, particularly intraparticulate organic matter. The results indicated that the organic carbon increase in organic manure-amended soil were possibly due to enhanced silt + clay subfractions, which then promoted macroaggregates formation. Applying organic manure could improve organic carbon sequestration and maintain its stability in aggregates, whereas mineral fertilizer only enhanced organic carbon in large macroaggregates, but with low stability.

The aim of the study was to evaluate the effect of cultivar, flesh colour, location, year and long-term cold storage on the total anthocyanin content (TAC) in the tubers of 12 potato cultivars with coloured flesh. TAC ranged from 17.0 to 750.1 mg cyanidin/kg fresh matter and was significantly affected by the genotype of the cultivar. The highest TAC was achieved in a three-year average in the cv. Vitelotte (371.0 mg/kg FM, 1.15-8.10 times higher than in the other cultivars). The purple or red colour of the flesh had no significant effect on the TAC. A significantly higher TAC (1.24 times) was determined in the Valečov location with a cooler climate in comparison with the Uhříněves location with a warmer climate. The TAC was significantly influenced by year, the highest values were found at both sites in the year with significant water stress. Storage (4°C, 6 months) significantly affected the TAC in seven out of eight cultivars; the TAC increased in four cultivars and decreased in three cultivars. This is probably due to different disposition of cultivars for the accumulation of sugars during cold storage.

Soil carbon transformation was observed in long-term stationary field experiments (longer than 20 years) at two sites with different soil-climatic conditions (Luvisol, Chernozem). The following crops were rotated within the trial: row crops (potatoes or maize)-winter wheat-spring barley. All three crops were grown each year. Four different fertilization treatments were used: (a) no fertilizer (control); (b) sewage sludge (9.383 t dry matter/ha/3 years); (c) farmyard manure (15.818 t dry matter/ha/3 years); (d) mineral NPK fertilization (330 kg N, 90 kg P, 300 kg K/ha/3 years). At the Luvisol site, the control treatment showed a tendency to decrease organic carbon (C_org) in topsoil. At organic fertilization treatments the content of C_org increased: sewage sludge - +15.0% (Luvisol) and +21.8% (Chernozem), farmyard manure - +19.0% (Luvisol) and +15.9% (Chernozem). At the NPK fertilization, the increase was +4.8% (Luvisol) and +4.7% (Chernozem). The increased C_org content was also associated with an increase of microbial biomass carbon (C_mic) and extractable organic carbon (0.01 mol/L CaCl₂ and hot water extraction). The ratio of C_mic in C_org was within the range 0.93-1.37%.

Humus substances (HS) influence the incorporation of carbon into soil aggregates in many ways. In this study the influence of HS and their fractions in the soil on the proportions of carbon (total organic, labile, non-labile) in water-resistant macro-aggregates (WSA) and differences between the amount of carbon in WSA in coarse-grained (CGS) and fine-grained (FGS) soils with dependence on the proportions of HS in the soil were determined. The experiment included three soils (Haplic Chernozem, Haplic Luvisol, Eutric Cambisol), each of them with two different soil textures (CGS, FGS) from four ecosystems (forest, meadow, urban, and agro-ecosystem). In CGS, higher proportions (52 and 50%) of smaller (< 1 mm) dry-sieved macro-aggregates (DSA) and also WSA were determined, while in FGS, higher proportions (51 and 53%) of larger DSA (> 7 mm) and WSA (> 2 mm) were detected. A negative correlation was recorded between the content of organic carbon in the fractions of WSA and the amount of extracted humic acids (HA) in CGS, and fulvic acids (FA) in FGS. In CGS, the correlation between the carbon content in WSA and HA bound with Ca²⁺ and Mg²⁺, which forms humates (HA2), was negative. In FGS, a negative correlation was recorded between the carbon content in WSA and free aggressive FA (FA1a) and free FA and those, which are bound with monovalent cations and mobile R₂O₃ (FA1) in the soil. In the case of FA1a, a negative correlation was recorded in FGS and also in CGS, however this influence was more marked in CGS than in FGS (by about 21% higher correlation). In CGS, the influence of HA and FA in soil on the content of labile carbon in aggregates was stronger than in FGS. In CGS, a higher proportion of carbon in aggregates was detected in the case of lower stability of HS and HA and, on the contrary, in FGS, a higher content of carbon in aggregates was detected in the case of their higher stability.

The concentrations of 16 polycyclic aromatic hydrocarbons (PAHs), which are on the United States Environmental Protection Agency (US EPA) priority pollutant list, were studied in ten different soil samples from Shengli Oil Field, China. The total PAHs concentrations in the sampled soils attained 1214.9-2965.1 ng/g (2159.6 ng/g on average). The highest total PAHs concentration was in the soil with a huge content of oil sludge, while the lowest was in fine soil environment areas. The soil contamination with PAHs in the study areas was classified as severe. The major pollutants were naphthalene, phenathrene, fluorine (Flu), pyrene (Pyr), while the detected concentration of benzo(a)pyrene (BaP), benzo(b)fluoranthene was relatively low. Among the 16 kinds of PAHs, the concentration increased in the order: 6 rings < 5 rings < 4 rings < 2 rings < 3 rings. The ratios of Flu/(Flu + Pyr) and indeno benzene(1,2,3-c,d)pyrene (IP)/(IP + BaP) were 0.46-0.48, and 0.36-0.64, respectively. Our results suggest that the main sources of PAHs were petroleum extraction and petroleum combustion. In addition, a small amount of PAHs originated from combustion of grass, woods, and coal.

The Štiavnické vrchy Mts. were strongly affected by pollution mostly from an aluminium plant in 1953-1989. This paper compares contamination of soils between Štiavnické vrchy Mts. and the neighbouring little polluted Kremnické vrchy Mts. from results of a 25-year study. After a decrease of emissions in Slovakia at the beginning of the 1990s the sulphate sulphur content, acidity and conductivity of soil water have decreased only on the surface and at a depth of 0.10 m at the study site in the Štiavnické vrchy Mts. At the depth 0.25 m the increase of sulphurization (23.68 kg/ha S-SO₄^2- per year) and acidity (pH 4.92) was observed. During the research, the total sulphate sulphur influx to this soil depth was 568.3 kg/ha. The average sulphur input in the study areas of the Kremnické vrchy Mts. decreased with depth: from 18.48 kg/ha/year in the surface humus to 6.85 kg/ha/year at a depth of 0.25 m. The maximum sulphur influx at the open plot was 24.06 kg/ha/year and in total 553.34 kg S-SO₄^2-. A small increase of acidity at soil depths of 0.25 m at some sites was observed also in the Kremnické vrchy Mts. Regression analysis revealed a statistically significant influence of sulphate sulphur content in the atmospheric precipitation on the sulphur amount in the soil water. A significant correlation was also observed between the precipitation amount and the sulphur content in soil water. Data from monitoring revealed significant differences between the sulphur amounts at depths of 0.10 m and 0.25 m in these study areas.

The leakage of pharmaceuticals present in soils towards groundwater is largely controlled by sorption of those compounds in soils. In some soils, soil aggregates are covered by coatings, which may have considerably different composition in comparison to that in an inner part of the aggregates. The aim of this study was to evaluate the sorption of three pharmaceuticals, which were applied in single or all compounds solutions, onto soil samples taken from the Bt horizon of a Haplic Luvisol. Analyses were performed on three types of disturbed soil samples: (1) entire aggregates, (2) aggregates from which coatings were removed, and (3) clay-organic coatings. Sorption of atenolol onto material from coatings was slightly higher than that onto material from the inner parts of the aggregates. On the other hand, sorption of sulfamethoxazole onto material from the coatings was lower than that from the aggregate interior. Both associates with a dominant fraction of clay particles (that are mostly negatively charged) in the coatings in comparison to soil composition in interiors and thus larger cation exchange capacity, which increased sorption of the positively charged atenolol and decreased sorption of the negatively charged sulfamethoxazole. Sorption of carbamazepine, which was in neutral form, did not substantially differ. The sorption of all three compounds did not decrease due to the competition between these compounds for the same sorption sites when applied simultaneously. Atenolol sorption was similar for both applications. Sorption of sulfamethoxazole increased when applied in solution with the other two compounds in comparison to its negligible sorption measured for the single compound solution likely due to sorption of the positively charged molecules of atenolol onto the negatively charged surface of soil components and reduction of repulsion between the soil components and the negatively charged molecules of sulfamethoxazole. Carbamazepine sorption also increased probably due to ionization of molecules due to dipole - induced dipole interaction between non-polar and polar molecules in solution.

Humic substances (HS) are an important stabilizing element in the formation of soil aggregates. The experiment included 6 soil types (Haplic Fluvisol, Haplic Chernozem, Cutanic Luvisol, Haplic Cambisol, Haplic Planosol, Rendzic Leptosol), each in four types of ecosystems (forest, meadow, urban, and agro-ecosystems). Soil macroaggregates were separated with the sieve (dry and wet sieve) to size fractions of net aggregates; humic acids (HA) and fulvic acids (FA) were divided into 3(4) fractions: free and bound with mobile R₂O₃, bound with Ca²⁺, and bound with mineral components and stable R₂O₃. The influence of HA and FA fractions on the proportion of dry-sieved macroaggregates (DSA) and wet-sieved macroaggregates (WSA) was different. Mainly HA bound with polyvalent cations had a positive influence. In the case of HS, their influence depends also on the components with which HA and FA are bound. WSA of the 0.5-1 mm size fraction that is an important indicator of changes in ecosystems, had a higher proportion in the ecosystems influenced by man (agro-ecosystem > urban >) than in the ecosystems close to nature (> meadow > forest ecosystems). The influence of ecosystem was reflected in the proportion of those fractions of DSA and WSA on which the effect of soil type and HS was not shown, and vice versa.

Non-exchangeable K release can greatly influence soil K fertility. This study was carried out to study the release of non-exchangeable K from 22 surface and subsurface soils of southern Iran using successive extraction with 10 mmol/l of CaCl₂ and oxalic acid in a period of 2-1368 h at 25 ± 1°C. Alfisols, Aridisols, Entisols, Inceptisols, Mollisols, and Histosols were among the studied soil orders. Illite, smectite, chlorite, vermiculite, kaolinite and palygorskite clay minerals were identified. The amount of non-exchangeable K varied from 95 to 506 mg/kg. Results showed that CaCl₂ and oxalic acid released 60 and 55% of non-exchangeable K from soils, respectively. The discontinuity in slope was found when the cumulative amount of released K was plotted versus time, supporting the multi-reactive nature of K exchange sites. The cumulative K release in soils ranged from 87 to 300 mg/kg for CaCl₂ and 78 to 300 mg/kg for oxalic acid which was well described by simplified Elovich and power function equations. The b constant of simplified Elovich as an index of non-exchangeable K release rate was in the range of 10 to 36 mg/kg for CaCl₂ and 11 to 36 mg/kg for oxalic acid. The highest b constant was measured in Inceptisols and Alfisols, while the lowest values were found in Entisols and Histosols. In conclusion, the K release pattern was similar for both extractants and affected by clay content and type, and soil depth.