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Objective: The aim of this study was to develop quantitative structure–pharmacokinetics relationship (QSPKR) models for a group of xanthine derivatives with proven pharmacological activity and to investigate its applicability for the prediction of the pharmacokinetics of these compounds. Methods: The SYBYL-X, KowWin, and MarvinSketch programs were employed to generate a total of fourteen descriptor variables for a series of new compounds: 7- and 7,8-substituted theophylline derivatives (GR-1–GR-8) and three well-known methylxanthines. Pharmacokinetic profiles of all compounds were determined after intravenous administration of studied compounds to cannulated male rats. Pharmacokinetic parameters were calculated using noncompartmental analysis. Results: Multiple linear regression revealed that logD was the main determinant of the variability in Vss, λz, and CL of the studied compounds. Moreover, λz and CL depended on LUMO and HEFO, while for Vz COAR was the only explanatory variable. The developed QSPKR models accounted for most of the variation in Vss, λz, CL, and fraction unbound (fu) (R2 ranged from 0.68 to 0.91). Cross-validation confirmed the predictive ability of the models (Q2 = 0.60, 0.71, 0.34, and 0.32 for Vss, λz, CL, and fu, respectively). Conclusions: The multivariate QSPKR models developed in this study adequately predicted the overall pharmacokinetic behavior of xanthine derivatives in rats.

Soil erosion and the loss of soil organic carbon (SOC) pools are considered serious environmental problems in undulating landscapes on loess covers, accompanied in some areas, such as south Poland, by the physical degradation of chernozemic soils. The aim of the present study was to identify the scale and reasons for spatial variation of the SOC pools in the intensely cultivated Luvic Phaeozems in one of the unique patches of chernozemic soils in Poland. This study, carried out in a soil catena located in the undulating Carpathian Foreland in south-east Poland, has demonstrated that the SOC pools can greatly differ on a very small scale, even in relatively less differentiated landscapes and in soils classified into the same group. The scale and reasons for the differentiation of the SOC pools depend on the method (depth) of calculation. The spatial differences were smaller and were mainly related to the SOC concentrations and the bulk density of the topsoil horizons, when calculated for depths of 0–30 cm and 0–50 cm. On the other hand, the SOC pools calculated for the 0–100 cm soil layer differed most significantly between the profiles in the catena, representing a continuous growing trend from the uppermost towards the lowermost part of the catena, and were clearly related to the total thickness of the humus horizon(s). The latter findings confirm that sheet erosion has a major impact on the spatial variation of SOC pools in an agricultural landscape. However, soil morphology and the distribution of SOC across the soil profiles suggest additional influences from historical pedogenesis and modern farming technology. The presence of black, thick and humus-rich chernic horizons in all soils across the catena indicates that modern farming must not degrade the soils, but, on the contrary, it can help in the restoration of even neo-formation of chernozemic soils (Phaeozems), if oriented towards the conservation of humus content, soil structure, and biological activity.

Artificial intelligence is already developed enough to perform mechanical and computerised tasks, but the ability to convey emotions and recreate human consciousness is currently being studied. This article will primarily deal with AI-generated literature, focusing mainly on short text extracts and poetry. The selected research method in this article is qualitative research. A linguistic analysis of individual texts was carried out, as well as a comparison of the texts themselves. An experiment was conducted in which a group of participants decided whether the presented text was written by a human or artificial intelligence. In addition, I examined the positions in the discussion whether AI poetry can be considered authentic.

Amphiphilic compounds in aqueous environment can aggregate and form structures with different physicochemical properties. This process enables, inter alia, the formation of lipid bilayers, which constitute the skeleton of cell membranes, but also intracellular membrane structures, the properties of which ensure the proper course of life processes. Other self-assembly structures are vesicles and three-dimensional structures, which in recent years have been used as drug delivery systems, especially for drugs poorly soluble in water. Self-assembling and formation of stable structures are caused by two opposing phenomena: hydrophobic and hydrophilic interaction. These intermolecular interactions of amphiphiles in the water environment determine the optimal area of the molecule at the interface surface and the entire three-dimensional structure of this molecule, which can be described by successive characteristic quantities: the volume of the hydrocarbon chain and the maximum effective length of this chain. A convenient and frequently used parameter, which contains information about the above values, is the critical packing parameter (CPP). Physiological factors (temperature, pH and digestive enzymes activity) affect amphiphilic compounds, which is reflected in the change of the CPP parameter value and the structures formed by these molecules. Knowing the CPP of a compound and how it changes in the physiological environment, course of the self-organization of the compound in the organism can be predicted. This review presents the literature values of CPP of amphiphilic compounds present in biological membranes, administered as drugs and used as drug delivery systems, as well as the changes in the value of this parameter during physiological processes. The presented articles report on structural changes occurring during the digestive processes, antimicrobial activity, and also pathological processes. The described methods for determining the CPP value, both experimental and theoretical, show that this parameter is a convenient tool that can be used in the process of designing drugs or drug delivery systems, as well as in assessing the side effects of drugs and other biologically active compounds administered to the organism.

Excessive agricultural intensification adversely affects soil quality, particularly in hilly terrain, leading to increased erosion. Anthropogenic denudation, intensified by tillage erosion, results in the displacement of soil material from hilltops and shoulders to their bases. The research hypothesis posits that tillage erosion adversely affects the microbiological and chemical properties of soils, especially at the hilltops of intensively cultivated areas. The study aimed to assess the microbiological and chemical properties of Luvisols cultivated under conventional plowing in the moraine region of the Southern Krajna Lakeland, Poland. The evaluation focused on the results of soil sample analyses taken from the hilltops and foothills of eroded mounds. Microbiological investigations included determining the abundance of actinomycetes, filamentous fungi, heterotrophic bacteria, cellulolytic microorganisms, copiotrophs, and oligotrophs. Additionally, pH values and the contents of phosphorus, potassium, magnesium, total organic carbon, and nitrogen were determined. A higher abundance of bacteria, actinomycetes, and copiotrophs was observed at the foothills. Statistically significant differences due to slope effects were noted for all chemical parameters, with higher concentrations of organic carbon, nitrogen, potassium, and phosphorus found in the foothill areas. Understanding denudation processes can contribute to sustainable soil resource use and agrocenosis conservation.

Peat organic soils play a major role in the accumulation of soil organic matter (SOM) and the mercury (Hg) cycle. Large mercury resources in peatlands can be a source of methylmercury for many decades and centuries, even if deposition is significantly reduced. The organic matter of peatland soils drained for agricultural use is subject to secondary transformation, which may affect the accumulation and resources of mercury. The aim of our work is to assess the secondary transformation of organic matter in the soils of drained peatlands of the temperate climate zone and to examine whether it affects mercury resources and profile distribution in organic soils. Field research was conducted in peatlands located in eastern Poland. In the present study, evaluation of secondary transformations occurring after drainage was based on observations of soil morphological characteristics, physical and chemical properties as well as fractional composition of organic matter of the identified soil horizons (to depth 70 cm). Standard cold vapor atomic absorption spectrometry (CV-AAS) was used to measure the total mercury content. In our research, we found a significant effect of the secondary transformation of organic matter occurring in drained peatlands of the temperate climate zone on the total mercury content and stock in soils. The highest content and differentiation of mercury occurred in murshic horizons (up to a maximum depth of 43 cm). The average mercury content of the distinguished soil horizons is grouped in the following series (in μg kg−1): M1 (212.0) > M2 (182.8) > M3 (126.3) > Pt (84.9). The mercury stock, up to a depth of 70 cm in the tested soils, ranged from 17.5 to 39.6 mg m−2. As much as 82.2% of soil mercury was found in the upper murshic horizons. We found strong correlations between soil properties characteristically variable in the secondary transformation process and total mercury content. The increased content of humic substances in murshic horizons caused a significant increase in the total mercury content. Our research is of great importance for soil monitoring, as the amount of determined mercury was greatly influenced by the depth of sampling (up to 25 cm). The results of the research should be taken into account when planning the restoration of peatlands of the temperate climate zone. There is a potential risk that elevated mercury concentrations in the upper murshic horizons may be a source of methylmercury for a long period of time. In peat soils with a high concentration of mercury, the risk of contamination with this toxic metal should be determined before re-irrigation.

ABSTRACT Background Radiation‐related screening guidelines for survivors of childhood cancer currently use irradiated regions (IR) to determine risk for late effects. However, contemporary radiotherapy techniques utilize volumetric dosimetry (VD) to determine organ‐specific exposures, which could inform need for late effect surveillance. Methods This cross‐sectional cohort study involved patients treated for cancer using computerized tomography‐planned irradiation at Children's Hospital Los Angeles from 2000–2016. Organs at risk were identified using both VD and IR. Under each method, Children's Oncology Group Long‐Term Follow‐Up Guidelines were applied to determine radiation‐related potential late effects and their correlative recommended screening practices. Patients served as their own controls. Mean number of potential late effects per patient and recommended screening practices per patient per decade of follow‐up were compared using paired t‐tests; comparisons were adjusted for diagnosis and gender using random effects, repeated measure linear regression. Results In this cohort (n = 132), median age at end of treatment was 10.6 years (range, 1.4–20.4). Brain tumor was the most common diagnosis (45%) and head/brain the most common irradiated region (61%). Under IR and VD, the mean number of potential late effects flagged was 24.4 and 21.7, respectively (−11.3%, p

Formalized classification of the class Isoëto-Nanojuncetea has not been performed in Poland. We used 69,562 relevés stored in Polish Vegetation Database. Based on the literature and expert knowledge we selected 63 diagnostic species for the Isoëto-Nanojuncetea class. Unequivocal classification was applied in this work according to Cocktail method. A set of formal definitions was established using a combination of logical operators of total cover of species in case of high-rank syntaxa while sociological species groups and cover of particular species were used for logical formulas describing class, alliances and associations. An Expert System was prepared and applied to classify the whole data set of PVD and 1,340 relevés were organized at the class level. We stratifies the data and finally we used data set of 903 relevés to prepare synoptic tables, distribution maps and descriptions of the syntaxa. Twelve associations and two plant communities were identified. Vegetation of the Isoëto-Nanojuncetea class occur in Poland’s central and southern part, with scattered stands in northern region. We described two new plant communities within Eleocharition and Radiolion alliance. The first formal classification of the Isoëto-Nanojuncetea class revealed a high diversity of ephemeral vegetation wetland found in Poland in the eastern boundary of their geographical distribution in Europe.

The research objective of this study was to determine whether and to what extent the form of use of Fluvisols (arable soil and grassland) of a Lower Vistula floodplain valley (Fordonska Valley, Poland) determined their relative organic matter properties, as compared with nearby riverbank sediments. Riverbank sediments were sampled from a depth of 0–20 cm, and soil samples from 0 to30 cm, all in three replicates. Basic physico-chemical soil properties were determined: texture, pH, and the contents of total organic carbon (TOC), total nitrogen (TN), dissolved organic carbon (DOC) and dissolved organic nitrogen (DON). Humic acids (HAs) were extracted by the Schnitzer method and analysed to assess their spectrometric parameters in the UV–VIS range and hydrophilic and hydrophobic properties. Riverbank sediment samples contained significantly lower TOC and TN contents than Fluvisols, regardless of land-use type. The TOC, TN, DOC and DON contents and properties of humic acids in the Fluvisol surface layer depended on land-use type, because the arable soils had significantly lower TOC, TN, DOC and DON contents than the grasslands, despite having a similar grain size (texture). Based on the A2/4, A2/6, A4/6 ratios, it was found that HA molecules isolated from the humus horizon of arable soils had a higher degree of maturity than HAs isolated from grassland soil samples. The spectrometric properties of humic acids isolated from riverbank sediments showed a higher degree of maturity than those from Fluvisols. This research showed that the properties of humic acids in Fluvisols are determined by the quantity and quality of organic matter transported in suspended matter that accumulates annually in flood valleys during flood events. The current land-use type of Fluvisols significantly influenced the properties of organic matter, and thus of humic acids. Therefore, these properties can be used to evaluate the transformation of organic matter that occurs in Fluvisols depending on the type of use.

Introduction: The high concentration of some trace elements in medicinal plants may lowering the value of herbal material, and may cause poisoning effects.

Parkinson’s disease (PD) is a progressive, neurodegenerative disorder primarily affecting dopaminergic neuronal systems, with impaired motor function as a consequence. The most effective treatment for PD remains the administration of oral levodopa (LD). Long-term LD treatment is frequently associated with motor fluctuations and dyskinesias, which exert a serious impact on a patient’s quality of life. The aim of our study was to determine the pharmacokinetics of LD: used as monotherapy or in combination with ropinirole, in patients with advanced PD. Furthermore, an effect of ropinirole on the pharmacokinetics of 3-OMD (a major LD metabolite) was assessed. We also investigated the correlation between the pharmacokinetic parameters of LD and 3-OMD and the occurrence of motor complications. Twenty-seven patients with idiopathic PD participated in the study. Thirteen patients received both LD and ropinirole, and fourteen administered LD monotherapy. Among 27 patients, twelve experienced fluctuations and/or dyskinesias, whereas fifteen were free of motor complications. Inter- and intra-individual variation in the LD and 3-OMD concentrations were observed. There were no significant differences in the LD and 3-OMD concentrations between the patients treated with a combined therapy of LD and ropinirole, and LD monotherapy. There were no significant differences in the LD concentrations in patients with and without motor complications; however, plasma 3-OMD levels were significantly higher in patients with motor complications. A linear one-compartment pharmacokinetic model with the first-order absorption was adopted for LD and 3-OMD. Only mean exit (residence) time for 3-OMD was significantly shorter in patients treated with ropinirole. Lag time, V/F, CL/F and tmax of LD had significantly lower values in patients with motor complications. On the other hand, AUC were significantly higher in these patients, both for LD and 3-OMD. 3-OMD Cmax was significantly higher in patients with motor complications as well. Our results showed that ropinirole does not influence LD or 3-OMD concentrations. Higher 3-OMD levels play a role in inducing motor complications during long-term levodopa therapy.

The aim of the research was to evaluate the chemical properties and enzymatic activity of arable soils which, for the period of 10 years, were fertilized with poultry manure (PM). Fertilization with PM resulted in a significant increase in the content of organic carbon and total exchangeable bases in soil. The application of that fertilizer increased the pH value. Fertilization with PM also slightly increased the total content of copper, manganese and iron. There was found, however, a significant increase in the total content of Zn. The annual application of 10 tonnes of PM significantly increased the content of phosphorus and potassium available to plants. That fertilizer inhibited the activity of both alkaline and acid phosphatase, which must be related to a very high content of phosphorus available to plants. Poultry manure resulted in higher values of the biological index of fertility of soil, whereas the activity of phosphomonoesterases was significantly lower.

Wprowadzenie na pokłady okrętów Marynarki Wojennej RP nowych okrętowych systemów rozpoznawczo-ogniowych (OSRO) wymusza potrzebę określenia prawidłowości ich wykorzystania w warunkach normalnych i zmiennych. W opracowaniu przedstawiono wybrane elementy projektu odzwierciedlającego czynniki charakterystyczne dla wyróżnionych badań na pozycji ogniowej w trzech obszarach: I; II i III. I obszar to pojęcia podstawowe niezbędne przy prowadzeniu badań, II obszar jest związany z prawidłowościami przygotowania OSRO do badań, III obszar odnosi się do prawidłowości wykonywania zadań rozpoznawczo-ogniowych z OSRO podczas ruchu jego nosiciela.

BACKGROUND: Elevated serum cancer antigen 125 (CA-125) is observed in some cervical cancers (CCs). Is the correlation of CA-125 with the presence of nodal events useful in predicting early metastasis to the lymph nodes?

The aim of the research has been to assay the contents of Zn, Cu, Mn, Fe, and Pb in soil and in the organs of wild Thymus serpyllum L. acquired from three natural habitats from the Kuyavia-Pomerania Province (Poland) not exposed to contamination with metals. As compared with the contents of the geochemical background of the soils in the region and the value of enrichment factor (EF), there was noted a considerable content of Pb in the soil from two locations. The Pb content in plant tissues in one of the three locations was higher than the admissible content specified by the World Health Organization WHO (above 10 mg kg−1 d.w.). As for the Zn content, only the plants from the locations with the relatively youngest phytocenosis met the conditions for herbs to be used for phytotherapy. The Zn content in the dry weight of the plants collected from the other two locations exceeded 50 mg kg−1. The risk of an elevated content of Zn and Pb in the plants makes it necessary to monitor the soil environment and to limit the collection of the plants from natural habitats, as well as to encourage the collection from controlled habitats.

Experimental surface pressure (π) and electric surface potential (ΔV) isotherms were measured for membrane lipids, including the following phosphatidylcholines (PCs)—1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC); 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC); 1,2-diarachidoyl-sn-glycero-3-phosphocholine (DAPC); and 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC). In addition, other phospholipids, such as phosphatidylethanolamines (represented by 1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine (DPPE)) and sphingolipids (represented by N-(hexadecanoyl)-sphing-4-enine-1-phosphocholine (SM)) were also studied. The experimental apparent dipole moments (μAexp) of the abovementioned lipids were determined using the Helmholtz equation. The particular contributions to the apparent dipole moments of the investigated molecules connected with their polar (μ⊥p) and apolar parts (μ⊥a) were theoretically calculated for geometrically optimized systems. Using a three-layer capacitor model, introducing the group’s apparent dipole moments (calculated herein) and adopting values from other papers to account for the reorientation of water molecules (μ⊥w/εw), as well as the for the local dielectric permittivity in the vicinity of the polar (εp) and apolar (εa) groups, the apparent dipole moments of the investigated molecules were calculated (μAcalc). Since the comparison of the two values (experimental and calculated) resulted in large discrepancies, we developed a new methodology that correlates the results from density functional theory (DFT) molecular modeling with experimentally determined values using multiple linear regression. From the fitted model, the following contributions to the apparent dipole moments were determined: μ⊥w/εw=−1.8±1.4 D; εp=10.2±7.0 and εa=0.95±0.52). Local dielectric permittivity in the vicinity of apolar groups (εa) is much lower compared to that in the vicinity of polar moieties (εp), which is in line with the tendency observed by other authors studying simple molecules with small polar groups. A much higher value for the contributions from the reorientation of water molecules (μ⊥w/εw) has been interpreted as resulting from bulky and strongly hydrated polar groups of phospholipids.

An irrevocable effect of the process of tillage erosion is truncation of the surface horizon and the translocation and accumulation of the eroded soil material at the foot of the slope. It concerns mostly fine soil fractions, humus and nutrients (C, N, P). The rate of that process depends on the original morphology of soil profiles and the susceptibility to erosion, the amount and intensity of precipitation, but mostly on the method and period of soil use. The aim of the paper was to determine the effect of the use of eroded Luvisols on the content of available phosphorus and the activity of phosphomonoesterases against the physico-chemical properties selected. Based on the analysis of variance, there was found a significant effect of the use of soils on the activity of phosphatases in the surface horizons of the analysed soils. There was found a significantly higher activity of alkaline phosphatase (0.094–1.896 mM pNP·kg–1·h–1) and acid phosphatase (0.152–2.905 mM pNP·kg–1·h–1) in the soil material sampled from the herbicide strips of 30-year apple tree orchards, as compared with the activity of those enzymes in arable soils, with a similar soil profile morphology (without Et horizon), grain size composition and the properties of the parent material. Activity of phosphatases in the soil surface horizon of the herbicide strips was positively and significantly correlated with organic matter. There was reported no significant effect of the use of the eroded Luvisols on the content of available phosphorus in surface horizons.

The chemical properties and enzymatic activity of the surface soil horizon were compared between an organic farm (OF) (crop rotation with legume plants, fertilisation with manure) and a conventional farm (CF) (simplified crop rotation, mineral fertilisation, chemical crop protection products). In the years 2001-2017 on the OF (near the village of Juchowo, northern Poland), a reduced tillage system (ploughless) was used, while plough cultivation was used on a CF located in its immediate vicinity. The parameters used to assess the properties of soils were: particle size composition, pH, total organic carbon (TOC) and total nitrogen (TN), dissolved organic carbon (DOC) and dissolved organic nitrogen (DON). The activity of dehydrogenases (DEH), catalase (CAT), alkaline phosphatase (AlP) and acid phosphatase (AcP) and the content of easily extractable glomalin-related soil protein (EEGRSP) were also determined. Sixteen years of soil use in accordance with ecological principles significantly increased the average content of TOC, NT, DOC and DON. Soil samples rich in TOC and DOC showed significantly higher DEH and AcP activity, and EEGRSP content. Statistical analysis showed that the activity of DEH, AlP and CAT in the soil was significantly higher for the OF than for the conventional cultivation system. Limiting soil cultivation procedures on the OF improved the balance of soil organic matter (SOM) and pH value, and significantly increased the content of EEGRSP as compared to the cultivation system used on the CF.

To assess the soil quality of Phaeozems and Luvisols from Kujawy region (Kujawy-Pomerania Province, Poland), the soil quality indicators such as: content of organic matter and nutrients, as well as bulk density were used. The soils showed similar inherent properties (soil texture, depth to parent material, type of clay) and management practices (tillage, crop rotation, nutrient application). The following properties were determined: bulk density, grain size composition, exchangeable acidity, concentration of available forms of potassium, phosphorus and magnesium, and the content of total organic carbon (TOC) and nitrogen (Nt). The amounts of dissolved organic carbon (DOC) and dissolved nitrogen (DN) were measured in the solution obtained after extraction with 0.004 M CaCl2. The stock of TOCs, Nts and DOCs, and DNs were calculated. The total organic carbon content in surface horizon of Phaeozems was significant higher (13.9-20.1 g·kg-1) than in Ap horizon of Luvisols (8.3-11.0 g·kg-1), which is a consequence of their origin. The stock of organic carbon in Ap horizon fell within 5.89 to 8.49 kg·m2 in Phaeozems and 3.80 to 4.81 kg·m2 in Luvisols. Although Phaeozems demonstrated a significant higher content of TOC, as compared with Luvisols, the amount of dissolved organic carbon was similar in both soil types, which points to a higher share of DOC in the total organic carbon content in Luvisols (up to 17.5% in Et horizon). The amounts of dissolved organic carbon and dissolved nitrogen and their stock do not depend on the type of soils if the management practices are similar.

This paper presents the results of an assessment of macro- and microelements in the sediments of lakes laying within protected areas in Poland – the Drawa National Park, the Wel Landscape Park and the Górzno-Lidzbark Landscape Park. In each lake two grab sediment sample were collected: one in the littoral zone and the other in the deepest part of the lake basin. Sediment samples analysed for their content of inorganic carbon (IC) and the loss on ignition (LOI at 550°C) and, according to these parameters classified into three sediment types. Micro elements were detected with SEM-EDX system and the bioavailability of Zn, Cu, and Fe was evaluated after an extraction with DTPA (diethylenetriaminepentaacetic acid) solution. The most diverse chemical composition of the sediments was observed in the lakes of the Wel Landscape Park Lacustrine sediments were characterized by the heterogeneous content of organic matter (from 11.70 to 52.89%), calcium carbonate (from 0.0 to 42.73%) and mineral fractions (from 38.24 to 79.46%). They consisted of three different types of gyttja (fine grain-size, clayey-calcareous, clayey). The highest content of trace elements was determined in fine grain-size gyttja, which results from their current sorption properties, as well as alimentation by river waters flowing into the lakes. The sediments contained relatively low concentrations of the analysed elements, which was reflected in the low values of the contamination factor (CF), the contamination degree (Cdeg), the geo-accumulation index (Igeo) and the enrichment factor (EF). Values of the Igeo point out also that these lake sediments were not contaminated by heavy metals. The total content of zinc and copper in some analyzed sediments was higher than the content assumed as acceptable for protected areas. The contribution of bioavailable forms of Zn and Cu ranges from 2.3 to 29.1% for Zn, and from 4.6 to 18.4% for Cu. The type of sediment, and the surface area largely determined the lake sediment chemical composition, while land-use in the catchments had a minor effect. This applies to both lakes of different parks and lakes within each of the parks.

For 10 years (1999-2008) there was investigated the effect of liming on soil pHKCl and on organic carbon, available forms of macroelements and DTPA-extracted forms of some metals in 6 different fertilization objects in a long-term experiment set up in 1948: without fertilization (0), straw + NPK (STR NPK), NPK, farmyard manure (FYM), FYM NPK, FYM NPKMgCa. As a result of the application of 12.0 t/ha of lime (4.3 t Ca/ha), an increase was found not only in soil pH value but also in organic carbon, plant available phosphorus, zinc and copper contents and a decrease in manganese content. Despite significant changes in the soil properties, they still varied across the long-term fertilization objects.

Próbki gleby ryzosferowej oraz pozaryzosferowej pobrano z 6 powierzchni użytków zielonych w obrębie Doliny Dolnej Wisły. Badaniom poddano tereny dolin zalewowych pomiędzy korytem Wisły a wałem przeciwpowodziowym w obrębie mezoregionów Doliny Fordońskiej i Kotliny Grudziądzkiej. Teren badań, znajdujący się w obrębie Chełmińskiego i Nadwiślańskiego Zespołu Parków Krajobrazowych, podlega corocznym zdarzeniom powodziowym. Osady fluwialane są deponowane w trakcie krótkotrwałych i najczęściej wiosennych wezbrań Wisły. Ilość deponowanego materiału w dolinach zalewowych zależy od zasięgu powodzi oraz lokalnych uwarunkowań związanych z rzeźbą terenu. W glebie ryzosferowej mniszka lekarskiego stwierdzono wyższą zawartość frakcji iłowej oraz materii organicznej w porównaniu do materiału glebowego strefy pozaryzosferowej. Całkowita zawartość Fe, Mn, Cd i Ni oraz ich form ekstrahowanych roztworem DTPA wykazywały zróżnicowanie w glebie ryzosferowej oraz pozaryzosferowej. Niższą całkowitą zawartość badanych metali stwierdzono w glebie ryzosferowej we wszystkich miejscach poboru próbek. Zawartość form FeDTPA i MnDTPA w badanych glebach była znacząco wyższa od zawartości, poniżej której rośliny odczuwają niedobór tych metali. Relatywnie wysoka zawartość materii organicznej oraz frakcji iłowej w glebie ryzosferowej powoduje, że metale zostają związane przez kompleks sorpcyjny, przez co ograniczona zostaje ich biodostępność. Zgodnie z Rozporządzeniem Ministra Środowiska z dnia 9 września 2002 r. określającym standardy jakości gleby dla obszarów poddanych ochronie na podstawie przepisów o ochronie przyrody - całkowita zawartość Cd i Ni w glebie pozaryzosferowej nieznacznie wyższa była od dopuszczalnej (odpowiednio 1.0, i 35.0 mg • kg−1). Z uwagi, że nie wykazano niekorzystnego oddziaływania pierwiastków śladowych na środowisko oraz że tereny dolin zalewowych są użytkowane rolniczo - do oceny zanieczyszczenia przyjęto standardy dla użytków rolnych. Według tych kryteriów badane gleby nie kwalifikują się do zanieczyszczonych kadmem i niklem.

Ocena wpływu wieloletniego użytkowania sadowniczego na całkowitą zawartość Cu, Zn, Mn i Fe w glebie oraz zawartość tych metali ekstrahowanych DTPA była celem niniejszych badań. Do badań wytypowano 3 sady jabłoniowe założone na glebach brunatnych wytworzonych z gliny zwałowej w regionie Doliny Brdy. Poziomy próchniczne badanych gleb charakteryzowały się znacznie wyższą całkowitą zawartością Cu i Zn w porównaniu do koncentracji tych metali w skale macierzystej. Udział miedzi ekstrahowanej roztworem DTPA w stosunku do jej całkowitej zawartości był wysoki i dochodził w poziomie próchnicznym do 24,6%. Stwierdzono istotną dodatnią korelację między całkowitą zawartością Cu i Zn oraz zawartością tych metali ekstrahowanych DTPA a zawartością węgla organicznego. Kwaśny odczyn w poziomach próchnicznych badanych gleb miał istotny wpływ na wzrost zawartości Cu, Mn i Fe ekstrahowanych DTPA, co potwierdziły dodatnie, statystycznie istotne współczynniki korelacji między tymi parametrami. Stwierdzone zawartości Cu, Zn, Mn oraz Fe nie przekroczyły dopuszczalnych norm przyjętych dla gleb nie zanieczyszczonych tymi metalami.

A tillage system can affect significantly the concentration of some heavy metals and their availability to plants which grow on the tilled soil. The purpose of this study has been to determine the impact of different tillage systems on the chemical properties of arable sandy loam soils under the same crop rotation, organic residue management and mineral fertilization. A single-treatment field experiment in a randomised block design was performed on sandy loam soils. Four-year tillage study data were compiled and compared with respect to full-inversion tillage (FIT), strip-till (ST) and reduced tillage (RT) systems. Soil samples were mineralised in a mixture of HF and HClO4 acids to determine the total content of metals. Total organic carbon (TOC) and total nitrogen (Nt) were also assayed. The content of available metal forms was determined using diethylene triamine pentaacetic acid (DTPA). The soil maintained in the FIT system contained significantly more Zn and Fe available to plants than the soil cultivated according to the RT and ST systems. The FIT and ST systems decreased the total Zn, Cu, Mn and Fe content in soil significantly compared with the RT system. Relative accumulation of the heavy metals at the depth of 30-50 cm can be related to the distribution of the clay fraction in soil profiles. In the topsoil (0-30 cm), the average content of TOC was significantly higher under the RT than under FIT and ST systems. The results confirm that a tillage system is one of the factors affecting the content of heavy metals, TOC accumulation and heavy metal distribution in sandy loam soils, although the pedogenic processes determining the quality of arable soils quality must be considered as well. [ABSTRACT FROM AUTHOR]

The aim of the study was to determine the influence of lithogenic and pedogenic processes on the distribution of iron forms in soils formed from glaciolimnic sediments, in basins of ice-dammed lakes in north-eastern Poland. The examined soils contained high amounts of clay minerals. However, when they are dry, they shrink and may form large deep cracks, which is unfavourable from the environmental point of view. Therefore, observation and recognition of processes occurring in these soils is crucial. The redox potential and oxygen diffusion rate were measured with a redox potentiometer. The free iron oxides were analysed in sodium citrate and dithionite extract, while amorphous iron oxides were analysed in ammonium oxalate according to the Tamm method. The content of crystalline iron oxides, crystallinity index and weathering index were calculated on the basis of the iron content. Total amounts of iron and manganese were measured after mineralisation in aqua regia. Redox potential results suggest anaerobic conditions in the soils studied. Correlation coefficients revealed statistically positive relationships between the content of total iron and manganese (r = 0.295) as well as manganese and redox potential values (r = 0.262). The soil parent material contained considerably more iron silicates, which suggests less intensive weathering, and was also distinguished by lower amounts of free iron. The results of the iron content determinations and calculated indices suggest that the analysed soils are young and the features of soil forming processes are merely marked. [ABSTRACT FROM AUTHOR]

Ash from incineration of cereal crop and oilseed rape straw can be used for soil fertilisation since it is a source of elements available to plants. At the Experimental Station in Mochełek (53°13' N; 17°51' E), owned by the UTP University of Science and Technology in Bydgoszcz, a pot experiment was performed to determine changes in the content of boron, copper, manganese, zinc and iron forms available to plants owing to the application of barley, wheat and rape straw ash at doses corresponding to 0.08-2.68 g kg-1. The pots were filled with loamy sandy soil. The paper provides evidence that the use of ash produced from incinerating straw of cereals and oilseed rape in soil fertilisation is a good way of ash waste management since such ash can be a valuable source of microelements essential for plants. Ash from barley, wheat, and oilseed rape straw can be used as fertiliser. Its application increases the soil pH values after application of a dose of 0.34 g kg-1 i.e. 1.0 Mg ha-1. Applied in the pot experiment, barley, wheat and oilseed rape straw ash at doses of 1.34-2.68 g kg-1 increased the richness of uncropped soil with forms of microelements available to plants by several to tens of per cent. Ash from straw of barley, wheat and oilseed rape affected similarly the chemical properties of soil. A higher content of microelements was observed in soil fertilised with ash from oilseed rape straw, as compared with the effects of barley straw ash application. Slight differences in the effects of the application of the tested types of ash to soil resulted from the differences in their chemical composition and different ash doses. [ABSTRACT FROM AUTHOR]

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