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Our objective has been to determine the total content of magnesium, iron, chromium and zinc, as well as the heavy metal fractions in selected natural fertilisers, such as swine and bovine manure and poultry litter from laying hens and broilers. The total content of the metals was determined by the ICP-AES method following dry mineralisation in a muffle furnace at 450°C and dissolving the ash in HCl (1:1). Fractions of Fe, Zn and Cr were isolated by the 3-step sequential fractionation method proposed by the Community Bureau of Reference (BCR). This study has shown that the analysed organic materials had different content of the determined metals. The largest amount of Mg was found in litter from laying hens and the largest amounts of Fe, Cr and Zn were in litter from broiler chickens. The smallest amount of Mg was found in swine manure, Fe and Cr were the least abundant in litter from laying hens, and the lowest Zn content was in bovine manure. The content of these four heavy metals was significantly differentiated by the origin of fertiliser. The exchangeable fraction F1 had the smallest share in the total Fe content among all the fertilisers. As for chromium, this fraction made the smallest contribution to the total Cr content in litter from laying hens and broilers while the reducible fraction F2 was the smallest part of the total content in both types of manure. Fraction F1 of zinc was the smallest in the total content in swine and bovine manure and while the oxidisable fraction F3 made up the smallest share in the total content of this metal in litter from broilers.
The research aimed to assess the effect of bottom sediment on the content, bioaccumulation and translocation of heavy metals in maize biomass. The investigations were conducted in 2006-2007 as a pot experiment on light soil of the granulometric composition of weakly-loamy sand. The experimental design comprised 3 treatments: without sediment (I), a 5% sediment admixture (II) and a 10% sediment admixture to the soil (III). Bottom sediment was added to the soil in the first year of the investigations. The content of Zn, Cu, Ni. Pb, Cd and Cr was determined using the ICP-EAS method in the plant material after its dry mineralization and ash solution in HNO3. The uptake of the above-mentioned metals by maize was computed alongside their bioaccumulation and translocation coefficients. The effect of bottom sediment admixture on heavy metal concentrations in maize was determined to be varied, e.g. a 5% dose of sediment added to soil decreased the content of all the analyzed heavy metals in the biomass of maize aerial parts, whereas a 10% admixture increased the content of Cu, Ni, Pb and Cr. The values of bioaccumulation coefficients revealed that an admixture of both doses of bottom sediment led to a decreased accumulation of Zn, Cu, Cd, Cr and Ni (5% dose) in maize aerial biomass. Moreover, the plant more easily accumulated Zn, Cd and Cu than Cr, Ni or Pb. Permissible amounts of heavy metals in plants to be used as animal fodder were not exceeded in the maize biomass.
The aim of this study has been to determine the influence of sewage sludge on the content of selected trace elements in Virginia mallow and in the soil after harvesting these plants. Sewage sludge was the source of nitrogen and phosphorus for the plants, while potassium was supplied in the form of mineral fertilisers. Virginia mallow plants grown without fertilisation served as the contnrol. The form and dose of sewage sludge did not have any larger effect on the concentrations of copper and zinc in the plants. The content of manganese and chromium increased as the the dose of either form of sewage sludge increased. In turn, the content of nickel in Virginia mallow tended to decrease as the doses of sludge rose. The biomass of Virginia mallow contained significantly more cadmium when fertilised with sewage sludge. Significantly more Mn and Pb accumulated in the soil which had been enriched with wet sewage sludge, while the soil treated with pelleted sewage sludge contained more Cd. The soil content of Zn, Mn, Pb and Cr tended to increase as the dose of sewage sludge increased. With respect to nickel and cadmium, their soil content was significantly differentiated by the applied doses of sewage sludge but the direction of these modifications was inconsistent. The forms or doses of sewage sludge applied left the content of copper in soil unaffected. Concerning the accumulation in the aerial parts of Virginia mallow plants, the heavy metals can be ordered as follows: Cd < Cu < Cr < Ni < Zn < Mn. Generally, sewage sludge applied in doses that covered the demand of Virginia mallow for nitrogen and phosphorus did not cause excessive increase in the content of heavy metals in the crop’s aerial biomass. However, an increase in the dose of sewage sludge tended to raise the content of mobile forms of heavy metals in soil after harvest of Virginia mallow.
Throughout 13 months, the municipal sewage sludge from sewage-treatment plant in Stalowa Wola was composted with fly-ash from combusted hard coal from the Stalowa Wola power plant; they were mixed in the following proportions: 80% sludge + 20% ash, 70% sludge + 30% ash, 60% sludge + 40% ash, 100% sludge. In order to assess the changes in Pb, Zn, Cu and Cd contents in composted wastes, composts were sampled on the day the experiment started, then on the 8th and 29th days of composting, as well as after 2, 4, 6, 8 and 13 months after the experiment beginning. Two types of wastes used for composting: the municipal sewage sludge and the hard coal ash, had similar contents of lead (19.8 and 19.5 mg·kg⁻¹) and copper (62.8 and 52.8 mg·kg⁻¹), while lower contents of zinc (43.2 mg·kg⁻¹) and cadmium (0.36 mg·kg⁻¹) were found in ash. Composting resulted in changes of heavy metal contents in the fertilizers obtained, depending on the composition of material composted and the time for which the process was carried out. Considering metals present in the 6-month compost (the standard), the fertilizers examined fell into following series: Pb: sludge + 30% ash > sludge > sludge + 20% ash > sludge + 40% ash; Zn: sludge > sludge+20% ash > sludge + 30% ash > sludge + 40% ash; Cu: sludge > sludge + 30% ash > sludge + 20% ash > sludge + 40% ash; Cd: sludge > sludge + 20% ash > sludge + 40% ash > sludge + 30% ash.
Species composition, density and biomass of earthworms were studied on 84 differently managed and polluted sites (field, grassland, deciduous forest, coniferous forest, alluvial sites and mine spoil). All these sites are constantly monitored since a decade. In 13 sites amounts of heavy metals increased from: Cd – 3 to 6 mg kg⁻¹, Zn – 303 to 606 mg kg⁻¹, Pb – 95 to 317 mg kg⁻¹, Ni – 31 to 55 mg kg⁻¹, Cr – 58 to 80 mg kg⁻¹, and Cu – 59 to 114 mg kg⁻¹ soil, that is up to 2000, 880, 1090, 295, 320, and 520% higher, respectively, than in unpolluted field sites. Results show that metal pollution is not a dominating factor determining the species diversity and densities of earthworms. Remarkable differences in the distribution of ecological groups were found between biotope types. The endogeic species (Aporrectodea caliginosa Savigny, Aporrectodea rosea Savigny, Allolobophora chlorotica Savigny, Octolasion cyaneum Savigny) dominate in field and grassland habitats. The anecic species (Lumbricus terrestris L., Aporrectodea longa Ude), however, appear mostly in grassland. Epigeic species (Lumbricus rubellus Hoffmeister, Lumbricus castaneus Savigny, Dendrobaena octaedra Savigny) are found exclusively (in addition to the other two life forms) in grassland and the forest habitats. Differences in earthworm biomass between monitoring sites are not related to ecological risk assessment. These differences may be largely dependant on soil properties e.g. pH and organic matter. A matrix with the ecological requirements of earthworm species was developed.
Research concerning the influence of sludge and ash composts on the heavy metal contents in reclaimed soil was conducted on experimental plots located on the area of mechanically devastated and intensively acidified soil. Once the plots of 15 m² surface area were deacidified with floated lime, 6-month-old composts were used on each in the ratio of 3, 6, and 9% of dry matter (90, 180 and 270 t·ha⁻¹) in the following variations: compost of municipal sewage sludge; compost: sludge (80%) + ash (20%); compost: sludge (70%) + ash (30%). Fertilizing the devastated soil with composts examined brought about an increase in the contents of analysed heavy metals, proportional to the dosage, but the values were still lower than the permissible levels for soils where sludge is used both for recultivation and agriculture. Taking into account metals present in the soil of 0-20 cm layers, the composts examined fell into following series: Pb, Cu, Zn: sludge + 30% ash compost > sludge compost > sludge + 20% ash compost; Cd: sludge + 30% ash compost > sludge + 20% ash compost; sludge compost.
The accumulation of heavy metals (Cd, Cu, Ni, Pb and Zn) by 19 plant species cultivated in the soil with natural content of those metals and contaminated with them was compared under pot experiment conditions. The elements were jointly applied into the soil as water soluble salts in a single dose (Me-1) and triple dose (Me-3). Cummulative capacity (on an everage) of all five studied heavy metals in the compared plants, irrespective of the metals contents in soil, raises in the following order: maize < oats < wheat < oil radish < ryegrass
Assessment of soil phosphatase activity, phosphorus and heavy metals content depending on the mineral fertilization. The paper presents the results of research into the activity of alkaline and acid phosphatase, the content of available phosphorus, heavy metals and total organic carbon, against in soil with mineral fertilization only. The first experimental factor was phosphorus, potassium, magnesium, calcium and sulphur fertilization in six fertilizer combinations: 1 – PKMgCaS, 2 – KMgCaS, 3 – PMgCaS, 4 – PKCaS, 5 – PKMgS, 6 – PKMgCa. The second factor was made up of nitrogen fertilization at the rates of: 0, 50, 100, 150, 200, 250 kg·haˉ¹ of N. Increasing nitrogen rates and a lack of liming increased the soil acidity inhibiting alkaline phosphatase, decreasing the content of available phosphorus in soil. A lack of phosphorus fertilization resulted in an intensive increase in the activity of both alkaline and acid phosphatase in soil. Due to the experimental factors applied, the content of the heavy metals assayed was as follows: zinc > copper > lead > cadmium.
17 samples of common sorrel were collected from natural sites in the Małopolska region. The content of selected heavy metals (zinc, copper, manganese, iron, chromium, nickel, lead and cadmium) were determined in individual plant organs. The greatest diversification occurred for cadmium, manganese and zinc; the smallest differences were noted for copper. Correlation coefficients between total soil heavy metal concentrations and their content in sorrel were generally low and very low; only the coefficients for cadmium and lead may be considered as high and very high. Allowable lead content was exceeded in all samples of sorrel leaves, whereas cadmium concentrations were in about 90% of the samples. Sorrel roots most strongly accumulated the metals, whereas the smallest content was found in the stems.
The studies were conducted to determine the impact of the anthropogenic factors in the form of horticultural cultivation and urban environment on soils of allotment and household gardens and the role of humus substance in binding heavy metals and the distribution of elements in a soil profile. The research covered the area of south-eastern Poland, where 3 cities were selected for sandy soils and 3 for silty soils. The high enrichment factor of humus horizons for Cd, Cr and Ni was observed in sandy soils but it was lower in the silty soils. Significant negative correlation coefficients between fractional composition of humus and content of Cd, Cr and Ni were only observed in sandy soils. There were no significant relations in terms of the content of mercury.
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