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The aim of this study was to evaluate changes in lead and chromium amounts in sequentially separated fractions and available forms of four sewage sludge (SS). Lead and chromium sequential extraction in SS was performed using BCR method. Single extractants were used to assay available and bioavailable forms of metals. It was found that Pb and Cr were detected in the largest amounts in organic forms, while the lowest levels were recorded for exchangeable ones. Sewage sludges from the small installations contained significantly lower amounts of metals (both available, bioavailable and sequentially separated fractions of sewage sludge) in comparison with those originating from the large treatment installations. Generally amounts of metals detected in sewage sludge were small in the years of this study, which should be considered a positive trend. Additionally, the bioavailability index (φ) and risk assessment code (RAC) indicated no negative impact of metals contained in the analysed SS on the soil environment.

This work presents quantitative changes of nickel in soil and plants under the influence of compost and fly ash. The research was carried out in a 3-year experiment on medium soil fertilised with compost or fly ash. The plants: narrow leaf lupine (Lupinus angustifolius L.), camelina (Camelina sativa L.), and oat (Avena sativa L.) were planted in consecutive years. The soil from the experiment was subjected to extraction by sequential analysis with the Community Bureau of Reference (BCR) method, and single extractions using 1 mol&middot, dm&minus, 3 HCl and DTPA solutions, obtaining the amount of nickel in various combinations with the soil solid phase. Total contents of the metal in soil and cultivated plants were determined. On the basis of Ni contents in the soil and cultivated plants, the bioconcentration factors and the risk assessment code were calculated. The type of amendments had a significant impact on the nickel content in lupine, for camelina and oat was the greatest in the control conditions. The differences between the amounts of Ni determined for bioconcentration factors were significant and depended on the amendments and nickel obtained by different methods. Regardless of the experimental conditions, the amount of Ni in the exchangeable bonds (Fr. I) had the greatest impact on the content of Ni in lupine and oat, whereas NiDTPA in the case of camelina.

This research deals with the effects of soil amendment with sewage sludge compost (SSC) on the accumulation of microelements (Cu, Zn, Mn, Ni, Fe) in plants&mdash, white mustard (Sinapis alba), triticale (Triticale) and white lupine (Lupinus albus)&mdash, cultivated on two contrasting soils (light vs. medium agronomic class). Additionally, the influence of experimental factors on variability of the harvest index (HI) was determined for individual plants and micronutrients. A 3-year pot experiment was conducted and SSC at the rate of 6 t&middot, ha&minus, 1 was applied into the soils. These changes were determined by ANOVA and subject to regression analysis and subsequently visualized. The study clearly demonstrated that SSC as an organic fertilizer had a significant, but weak effect on the microelements level variability in the shoots and grains of plants cultivated in crop rotation. Regardless of the experimental factors, on average, the plants accumulated higher amounts of Cu, Zn and Mn in the grains, and Fe and Ni in the shoots. Harvest index values confirmed the significance and variable translocation of microelements within plant organs. The influence of SSC on micronutrient contents in plant organs was more significant in the case of medium soil.

This research deals with the effects of soil amendment with sewage sludge compost (SSC) on long–term quantitative changes of available microelements [iron (Fe), zinc (Zn), manganese (Mn), copper (Cu)] in two types of soils using various extraction solutions [diethylenetriaminepentaacetic acid (DTPA) and hydrochloric acid (HCl)]. These changes were visualized using principal component analysis (PCA) and hierarchical cluster analysis. A 3-year pot experiment was conducted in a randomized, factorial design with two soils (light vs. medium) and a treatment with SSC at the rate of 6 Mg ha−1. The application of SSC to the light soil increased the HCl-extractable Cu, Zn, Mn, and Fe. The effect of SSC application on the microelement quantitative changes was lower in the medium soil, as shown primarily by DTPA extraction. The results of the PCA highlighted that one can correctly conclude on the basis of the limited collection of data without loss of information, which is incorporated by individual microele...

The study discusses changes in lead contents in soil and crops after application of compost and fly ash. A three-year experiment was conducted on narrow-leaved lupine (Lupinus angustifolius L.), camelina (Camelina sativa L.) and oat (Avena sativa L.), which were grown on medium soil fertilised with compost or fly ash (FA). The lead amounts in various combinations were evaluated using sequential (BCR analysis) and single (DTPA solution) methods. The total contents of lead and amounts of selected macronutrients were assessed in the biomass of plants. The Pb contents in the soil and plants were used to calculate the risk assessment code (RAC), individual contamination factor (ICF), bioconcentration factor (BCF) and contamination coefficient level (CCL). Lower amounts of bioavailable Pb in the soil were observed as a result of compost and FA application. Fly ash immobilised Pb more effectively, as evidenced by the BCF and CCL values. The increase in the Pb contents in the sequentially separated fractions and in plant biomass were caused by applied compost or FA. The Pb contents in exchangeable forms decreased, whereas its contents in residual forms increased.

Sewage sludge derived from municipal sewage treatment plants is an important source of macronutrients, micronutrients and organic matter. For this reason composting of sewage sludge, along with combustion and co-combustion, is a new management priority in Poland. In this study six composts of different origin and composition were evaluated in terms of their abundance in phosphorus, because it is an essential nutrient for all living organisms. Analyses were conducted on the samples at the initial and at the maturation phase of composting. The bioavailability of phosphorus was estimated on the basis of amounts of the nutrient in isolated fractions using the sequential extraction method. First of all quantitative changes of the total nutrient content and its amounts in separated fractions were dependent on the mixture composition. Irrespective of compost type, 34.5–75.0% of the total amounts of phosphorus were found in hardly available combinations (Fr. III), while available phosphorus forms (Fr. I) accounted for only 6.6–21.6%. As a result of composting together different organic wastes an increase was observed both in the total content and the amounts of this nutrient in separated fractions. This phenomenon was observed particularly in composts with smaller levels of sewage sludge (30–40%), characterised by rapid organic matter decomposition, which was indicated by higher bioavailable amounts of phosphorus. Under such conditions the content of P ranged between 3.68 and 7.4 g kg−1. In comparison to the labile pool of P obtained for matured composts C5 and C6 (65 and 75% of sewage sludge in their composition) amounting to 2.45–3.0 g kg−1 the above values were considerable. Bioavailable phosphorus contents potentially introduced to soil with composts doses calculated at 170 kg total N/ha/yr ranged from 69.8 to 80.2 kg for compost with the lowest share of sewage sludge and from 11.2 to 20.7 kg for compost with the highest share of sewage sludge.

The article presents the work of the Water Treatment Plant in the town of Otoczna, located in the Wielkopolska province, before and after the modernization of the technological line. It includes the quality characteristics of the raw water and treated water with particular emphasis on changes in the quality indicators in the period 2002 -2012 in relation to the physicochemical parameters: the content of total iron and total manganese, the ammonium ion as well as organoleptic parameters(colour and turbidity). The efficiency of technological processes was analysed, including the processes of bed start up with chalcedonic sand to remove total iron and manganese and ammonium ion. Based on the survey, it was found that the applied modernization helped solve the problem of water quality, especially the removal of excessive concentrations of iron, manganese and ammonium nitrogen from groundwater. It has been shown that one year after modernization of the technological line there was a high reduction degree of most parameters, respectively for the general iron content -99%, general manganese - 93% ammonia - 93%, turbidity - 94%. It has been proved, that chalcedonic turned out to be better filter material than quartz sand previously used till 2008. The studies have confirmed that the stage of modernization was soon followed by bed start-up for removing general iron from the groundwater. The stage of manganese removal required more time, about eight months for bed start-up. Furthermore, the technological modernization contributed to the improvement of the efficiency of the nitrification process.

In recent years, sewage sludge production in Poland has increased sharply. Composting is one of the most preferable methods for sewage sludge utilization. Compost can improve the physical and chemical properties of soil. However, the quality of sewage sludge composts should be assessed before soil application by using biological and chemical methods. A germination test is used as a biological index to determine the possible phytotoxic effect of composts. Chemical methods are helpful in assessment of availability of metals to plants. This study has been conducted to validate the effect of composting process on phytotoxicty, speciation and availability of copper and nickel in sewage sludge composted with sawdust and wheat straw. The composting process of organic wastes was carried out in chambers of a bioreactor for 28 days; afterwards each chamber was emptied and the content was stored in a closed room for 3 months to allow the maturation process to complete. Samples for analysis were collected at three characteristic phases of the composting process: mesophilic, thermophilic and mature compost. Determinations of the changes in metal speciation as well as metal bioavailability were achieved, respectively, with the technique of BCR sequential analysis and single extraction method using DTPA. Phytotoxicity of the analyzed composts was evaluated with the germination index using cress seeds. It was found that an increasing proportion of sewage sludge in composted mixtures increased copper and nickel content in compost fractions as well as bioavailable quantities of these metals. The germination index increased only during the composting process of a mixture containing 30% of sewage sludge. The compost with 75% share of sewage sludge strongly inhibited germination of cress seeds. The process of compost maturation resulted in an increase of copper in fractions I and III. However, the smallest amounts of copper were determined in exchangeable bonds and the highest ones were determined in bonds with organic matter and sulphides. Composting sewage sludge with sawdust and wheat

In the present work, we aimed to study the effect of quantitative changes of micronutrients (Cu, Zn, Mn) in soil and plants caused by wood ash applied into the soil in increasing doses. A pot experiment with medium textured soil, white mustard as a test plant and six amendment treatments (doses of wood ash: 0, 1, 5, 10, 20, 30 Mg·ha-1) was performed. Total contents of Cu, Zn and Mn were determined in soil and plant samples. Single (DTPA and HCl) and sequential (BCR) extractions were used to evaluate the available amounts of metals and their distribution in fractions. A plant’s ability to accumulate metals from soils was estimated using the bioconcentration factor (BCF), which is defined as the ratio of metal concentration in the plants to that in soil. The increasing doses of wood ash increased total and available contents of trace elements, especially Cu and Mn. The distribution of metals among particular fractions depended mainly on their geochemical character. The highest content of Cu was found in the reducible and oxidisable fractions, whereas, the greatest amounts of Zn and Mn were in the exchangeable and reducible fractions, and the lowest in the oxidisable fraction. Despite small wood ash influence on metal distribution in the individual soil fractions, increasing doses of wood ash increased the amounts of Cu, Zn, Mn in easily soluble fractions, which are potentially available to plants. As a result of wood ash increasing doses application, the higher amounts of Cu, Zn and Mn in plant tissues were found. However, only in the case of Zn, the value of BCF indicated on such accumulation in the plants.