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Mushroom production generates a considerable amount of spent mushroom substrate, difficult to utilize at the site of production. The high amount of organic matter and nutrients in the waste justifies its environmental use. However, waste entering the environment undergoes transformations, the direction and intensity of which depend on, among other things, environmental conditions. Extreme environmental conditions (such as very low or high pH) can significantly change the properties of introduced material and, as a result, pose a risk to the environment. The aim of this study was to determine the effect of pH value during leaching on chemical properties of the leachates obtained from the spent mushroom substrate. The leaching behaviour test was conducted taking into account the effect of pH on leaching with the initial acid/base addition (the procedure was conducted according to the PN-EN 14429 standard). The content of selected macroelements and heavy metals in the leachates was determined by inductively coupled plasma optical emission spectroscopy. The leachates were obtained at nine pH values (from 3 to 11.5, including natural pH of the material amounting to 7). The highest element content was recorded in the leachates obtained after the strongest acidification of the spent mushroom substrate. As a rule, the content of leached macroelements decreased as the pH increased. The content of leached Mn and Zn also decreased as the pH increased (contrary to the case of Cu). In the case of Fe, after the initial reduction in its content, an increase was recorded in strongly alkaline samples. Element content in acid leachates was as follows: Ca > K > P > Mg > Mn > Zn > Fe > Cu > Cr > Cd > Ni. Only traces of Pb were found in the leachates (regardless of pH) as well as traces of Ni, Cd and Cr (except the leachates with the lowest and/or highest pH). [ABSTRACT FROM AUTHOR]

Waste application, beneficial in terms of soil abundance in nutrients, cannot lead to soil contamination. The incubation experiment aimed at assessing the effect of applying sulfur pulp (waste material containing elemental sulfur) and ground phosphate rock on the availability of heavy metals in soils. The experiment was conducted on two soils with different soil category: medium and heavy, both of acid reaction and not contaminated with heavy metals. Doses of sulfur pulp and phosphate rock were set based on soil abundance in sulfur and phosphorus, guidelines on the limit content of these elements in soils, and on the principles of crop fertilization. Doses of 20 and 40 mg S as well as 40 and 80 mg P · kg-1 DM were added to medium soil; 30 and 60 mg S as well as 60 and 120 mg P · kg-1 DM were added to heavy soil. The experiment comprised: control soils (without additions), soils with only sulfur addition (in both doses), soils with simultaneous sulfur and phosphorus addition (in both doses). The content of available forms of heavy metals (Zn, Mn, Ni, Cd, Pb) in the soils was determined after 90 days of incubation. The elements were extracted with: 1) a mixture of 0.1 mol ∙ dm-3 hydroxylammonium chloride and 1 mol ∙ dm-3 ammonium acetate; 2) 0.01 mol ∙ dm-3 calcium chloride. The element content in the solutions was determined by inductively coupled plasma optical emission spectroscopy (ICP-OES). A higher content of trace elements was recorded after extraction with a mixture of hydroxylammonium chloride and ammonium acetate than after extraction with calcium chloride. Trace content of Cd and Pb was extracted with calcium chloride from both soils. Moreover, trace content of Ni was extracted from the medium soil with both reagents and trace content of Cd was extracted from the heavy soil with the mixture of hydroxylammonium chloride and ammonium acetate. Introduction of sulfur pulp and phosphate increased the content of manganese extracted with calcium chloride (especially from the medium soil). In other cases, no significant effect of the applied materials on the content of the analyzed forms of trace elements in both soils was recorded, or the effect was small and concerned only certain fertilization treatments. The element content in eluates obtained after extraction with calcium chloride was as follows: Mn > Zn > Ni (regardless of soil category). The element content in eluates obtained after extraction with the mixture of hydroxylammonium chloride and ammonium acetate was as follows: Mn > Zn > Pb > Cd > Ni (medium soil) and Mn > Pb > Zn > Ni (heavy soil). [ABSTRACT FROM AUTHOR]

The capacity of macroalgae for bioaccumulation of harmful elements is beneficial from the point of view of water treatment processes. Nevertheless, it is a threat to marine biocenoses, particularly to organisms on the individual levels of the trophic chain. Since algae have a great potential to bind trace elements, these organisms are often used as indicators of marine environment pollution. The aim of this study was to assess the content of Pb, Cd, B and Ba in water and algae collected in the region of Makarska Riviera. To achieve the pursued objective, in August 2016 samples of water and algae (Cystoseira barbata and Ulva rigida species) were collected from nine sampling points located in the following towns: Makarska, Podgora, Baška Voda, Split (John Paul II Street), Stobreč, Podstrana, Omiš, Mimice and Drvenik. The laboratory samples of algae were subjected to wet mineralization in a closed system with the use of microwave energy. The content of elements in the water and in the digested algae samples was determined using the emission spectrometry, on Optima 7600 DV manufactured by Perkin Elmer. The results of the conducted research indicate slight anthropogenic water enrichment with all the investigated elements. Generally, the highest content of the studied elements was determined in the water collected in Split, Stobreč, Podstrana and Omiš, compared to samples from other sampling points. On the other hand, the content of elements in the algae does not point to a risk to the natural environment and is characteristic for unpolluted regions. The content of the studied elements in the water decreased in the order: B > Pb > Ba > Cd; in the biomass of algae of the Cystoseira barbata species in the order: B > Pb > Ba > Cd; and of the Ulva rigida species – B > Ba > Pb > Cd. With the exception of cadmium, considerable differences in the concentration of the studied elements with respect to the algae genus were recorded. Higher amounts of boron were determined in the biomass of Cystoseira barbata, whereas Ulva rigida contained more lead and barium. The mean bioaccumulation factors of individual elements in the biomass of the algae ranged between 15.39 and 3728. The highest value of the bioaccumulation factor was determined in the case of barium, whereas the lowest – in the case of boron. [ABSTRACT FROM AUTHOR]