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The purpose of our study was to evaluate the spatial arrangement of carbon pools and humic substances maturity in cultivated chernozem soil adjacent to black locust shelterbelt. A plot on arable land adjacent to midfield shelterbelts in southern Poland (Proszowice Plateau) was chosen. Soil samples were taken at different distances from the shelterbelt from a depth of 0-25 cm. Samples were also collected from under the shelterbelt. The pools of organic carbon were highest in samples taken from the farmland closest to the black locust trees. As distance from trees increased, content of humic substances and fulvic acids was found in cultivated soil to be significantly lower. Based on the van Krevelen diagram, it can be concluded that the most mature and the most stabilized humic acids are those in the soil located directly adjacent to the trees.
The objective of the study was to monitor the activity of soil enzymes related to C, N and P transformations as well as some chemical parameters as influenced by an area covered with black locust (Robinia pseudoacaciaL). Samples of typical brown soil were collected from the surface layer of a cultivated field (0 - 24 m, every 2 m) adjacent to a planted area under black locust trees. Activities of the enzymes of the C-cycle (β-glucosidase), N-cycle (nitrate reductase, arginine deaminase and urease), P-cycle (alkaline and acid phosphatases) and dehydrogenases were determined colorimetrically. Moreover, pH in KCl, CORG, NTOT, PE-R and N-NH₄⁺ determinations were made. Significant differentiation of chemical parameters and enzymatic activity (except for acid phosphatase activity) was noted with increasing distance from black locust trees. CORG, NTOT concentrations and dehydrogenases, alkaline phosphatase, urease andβ-glucosidase activitiesdecreased with the distance fromR. pseudoacaciawhile PE-Rand N-NH₄⁺contents as well as nitratere ductase and deaminase arginine positively correlated with the distance from the black locust stand.
The aim of the present research work was to evaluate the influence of lithogenic conditions on the physico-chemical properties, quantity and quality of humus components in the black earths from the Małopolska Upland. Soil samples were collected from 5 soil profiles which represented proper black earth (profiles No. 1-4) and degraded black earth (profile No. 5). All the investigated soils were under sward. The examined black earths were characterised by different physico-chemical properties strongly related to the parent rock type. Their pH level and sorption capability were decreasing with a decrease in the clay content of the soil texture. Humus resources were the lowest in sandy black earths (average 212 t ha-1) and the highest in the black earh derived from clay (454 t ha1). In the humus composition of the examined black earths, humic acids dominated over fulvic acids. In the A horizons, the Ch:Cf ratio was close to 1, and lower in the upper parts of these horizons which is typical of turf soils. Humus horizons in some of the investigated black earths were classified as epipedon anthropoid according to phosphorus content soluble in 1% citric acid (109 P kg-1 soil).
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Odpornosc gleb poludniowej Polski na zmiany odczynu

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The buffering curves (determined after Arrhenius method) (fig. 2) have been drafted and the buffering areas have been measured (tab. 2) in order to estimate the buffer capacities of the South Poland soils. The influence of the physico-chemical soil properties on the buffer capacities of soils has been estimated for all genetic horizons of 30 soil profiles (tab. 1 and 2 contain results for 10 selected profiles) which belong to various taxonomic units of the Proszowice Plateau, the Niepołomice forest, the Podhale region and the Tatra Mts. The buffering of soils depends mainly on the soil reaction, the total exchangeable bases and the hydrolitic acidity (tab. 3). Podzols and brown soils (especially under forestes) are the most sensitive to the acid effect, while the most resistant are chernozems and alluvial soils as well as low peat soils. High peat soils and podzols are the most resistant to the base effect while chernozems are the least resistant ones (fig. 4). The resistance of different genetic horizons of the examined soils is not alike and results from the presence of differentiated buffers conditioned by various soil forming processes (fig. 3).
The aim of studies was to determine the total contents of Zn, Pb, Ni and Cd in soil profiles and in sward plants on selected grasslands of Wieliczka Foothills and Podhale, as well as to estimate the correlation between the concentration of above mentioned metals in the soils, soil pH-values, and their contents in overground parts of the plant. The influence of pH on the absorption of investigated heavy metals by plants of grassland sward in case of Cd and Ni was statistically significant. The Cd content in dry matter of sward plants taken from the major part of investigated grasslands exceeds the admissible limit of this metal concentration in the fodder. Only in sward taken from carbonate soils, the content of Cd is lower than 0.5 mg/kg d.m.
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The bedrock opoka has been lately reported as an appropriate reactive media for onsite wastewater treatment systems due to its high phosphorus (P) sorption capacity. However, variations on its chemical composition may affect its reactivity with P, therefore leading to a variable P removal effi ciency. In this paper, the P-sorption capacity of three different types of opoka from the region of Miechów, Poland, is reported. According to the silica and carbonate content, opoka samples were classifi ed as light--weight and heavy-weight opoka. When heated over 900°C, opoka showed a very high P-sorption capacity that was well correlated to its Ca content. P-sorption isotherms from batch experiments with an artifi cial P solution were plotted and fi tted to the Langmuir and Freundlich adsorption models. The Freundlich isotherm appeared to model better the P-sorption of light opoka and the Langmuir isotherm of heavy opoka, suggesting different dominating mechanisms of P-sorption by light and heavy opoka.
The effect of pesticides used in apple orchards as chemical protection on the activity and selected physico-chemical and chemical properties of soils in this orchard was studied. Pesti­cides and especially herbicide fallow applied to the soil have decreased a content of humus and an amount of excrements of soil fauna, both: earthworms and mesofauna.
Phosphorus (P) in wastewater is an important source of pollution, but properly managed, it can become a resource. Reactive filter media with a high affinity for P are promising in reducing P from effluents al­lowing nutrient recycling. In this study, three calcium-rich substrates (Filtra P, Polonite, wollastonite) with ability to remove P from wastewater have been saturated with P and tested as potential fertilizers in a pot experiment. Polonite had a relatively higher P content than Filtra P and wollastonite after saturation. all three materials tended to improve the yield of barley compared with the control treatment. Polonite induced the highest yield per unit of amendment from all three materials due to its higher P content, which could be shown in a higher ammonium lactate (AL)-extractable P in soil after harvesting. The application of the substrates slightly increased soil pH and decreased the hydrolytic acidity.
In this paper, the current problems associated with the classification of brown earths, are presented. According to the Polish Soil Classification (PSC) (1989, 2011), base saturation is the main parameter for identifying eutrophic and dystrophic brown soils. In practice, however, it is not possible to determine the base saturation value in the field. Therefore, the aim of this study was to estimate the base saturation using a regression equation and create a field guide for brown earths, based on the pH value, measured using a Hellige indicator, and the calcium carbonate content. Determination of the pH ranges enabled the classification of brown earth types in the field. These results suggest that pH can be used as a proxy for base saturation especially in the field. A change in the hierarchy of soil (sub)types is proposed for the new Polish Soil Classification.
In recent years, sustainable crop development has played a key role in current strategies to improve roots activity, which increase nutrients uptake in pulse crop. Our study presents the relationship between root system morphology, inoculant application with and without foliar fertilization and nitrogen accumulation in soil and plants. Two inoculants: Nitragina and IUNG, foliar fertilizer (Photrel), as well as two pea cultivars were studied in three years (2009–2011) period. The research has shown that bacterial inoculants have signifiant inflence on the selected parameters of pea root systems. Gel inoculant signifiantly increased mean root diameter (0.44 mm), compared to control (0.33 mm), whereas combination of Nitragina inoculant with micronutrient fertilization signifiantly increased root length density (1.05 cm·cm⁻³), compared to control (0.85 cm·cm⁻³). Additionally, the bacterial inoculant IUNG has signifiantly decreased the root length density in roots classes between 0.2–0.5 mm in the most humid year. The impact of inoculants on roots parameters was strongly related to weather conditions. In a dry year, a signifiant decrease of mean root diameter, specifi root length and increase of root dry mass were observed. Nitrogen accumulation in seeds signifiantly increased after gel inoculant application. A higher N content was proven in the fodder cultivar, but the edible cultivar was observed to accumulate more N in the seeds, which caused a Nitrogen Harvest index for this plant (80.0%).
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