Olive oil production is one of the most relevant agroindustrial activities in the Mediterranean region and generates a huge amount of both solid and semi-solid wastes, the uncontrolled disposal of which might lead to serious environmental problems. Due to its organic matter and mineral nutrient content, the waste material can be applied to agricultural soil as a fertilizer. However, due to its high organic matter content, dry olive residue (DOR), commonly called "alperujo," has the potential to immobilize risk elements in contaminated soils. The main objective of this study was to assess the possible effect of DOR on sorption of risk elements such as cadmium (Cd), lead (Pb), and zinc (Zn) in the soil. A set of batch sorption experiments were carried out to assess the ability of DOR to adsorb Cd, Pb, and Zn where the effect of the preceding biotransformation of DOR by four species of fungi: Penicillium chrysogenum, Coriolopsis floccosa, Bjerkhandera adusta, and Chondrostereum purpureum was compared. The Freundlich and Langmuir sorption isotherms were calculated to assess the sorption characteristics of both transformed and non-transformed DOR. The results showed good potential sorption capacity of DOR, especially for Pb and to a lesser extent for Cd and Zn. Better sorption characteristics were reported for the biotransformed DOR samples, which are expected to show higher humification of the organic matter. However, the desorption experiments showed weakness and instability of the DOR-bound elements, especially in the case of Zn. Thus, future research should aim to verify the DOR sorption pattern in contaminated soil as well as the potential stabilization of the DOR element bounds where the increase of the pH levels of the DOR samples needs to be taken into account.

• Klíčová slova
• Dry olive residue, Fungal pretreatment, Risk elements, Sorption,
• MeSH
• adsorpce MeSH
• biotransformace MeSH
• houby metabolismus   MeSH
• kadmium chemie   metabolismus   MeSH
• látky znečišťující půdu chemie   metabolismus   MeSH
• odpadní produkty analýza   MeSH
• Olea chemie   metabolismus   MeSH
• olovo chemie   metabolismus   MeSH
• půda chemie   MeSH
• půdní mikrobiologie MeSH
• zinek chemie   metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Středomoří MeSH
• Názvy látek
• kadmium MeSH
• látky znečišťující půdu MeSH
• odpadní produkty MeSH
• olovo MeSH
• půda MeSH
• zinek MeSH

On the basis of a previous study performed in our laboratory, the use of organic and inorganic amendments can significantly modify the Hg mobility in soil. We have compared the effectiveness of organic and inorganic amendments such as digestate and fly ash, respectively, reducing the Hg mobility in Chernozem and Luvisol soils differing in their physicochemical properties. Hence, the aim of this work was to compare the impact of digestate and fly ash application on the chemical and biochemical parameters in these two mercury-contaminated soils in a model batch experiment. Chernozem and Luvisol soils were artificially contaminated with Hg and then incubated under controlled conditions for 21 days. Digestate and fly ash were applied to both soils in a dose of 10 and 1.5 %, respectively, and soil samples were collected after 1, 7, 14, and 21 days of incubation. The presence of Hg in both soils negatively affected to processes such as nitrification, provoked a decline in the soil microbial biomass C (soil microbial biomass C (MBC)), and the microbial activities (arylsulfatase, and β-glucosaminidase) in both soils. Meanwhile, the digestate addition to Chernozem and Luvisol soils contaminated with Hg improved the soil chemical properties (pH, dissolved organic carbon (DOC), N (Ntot), inorganic-N forms (N-NH4 (+) and N-NO3 (-))), as consequence of high content in C and N contained in digestate. Likewise, the soil MBC and soil microbial activities (dehydrogenase, arylsulfatase, and β-glucosaminidase) were greatly enhanced by the digestate application in both soils. In contrast, fly ash application did not have a remarkable positive effect when compared to digestate in Chernozem and Luvisol soil contaminated with mercury. These results may indicate that the use of organic amendments such as digestate considerably improved the soil health in Chernozem and Luvisol compared with fly ash, alleviating the detrimental impact of Hg. Probably, the chemical properties present in digestate may determine its use as a suitable amendment for the assisted-natural attenuation of mercury-polluted soils.

• Klíčová slova
• Digestate, Fly ash, Mercury, Microbial activity, Microbial biomass, Nitrification, Soil pollution,
• MeSH
• arylsulfatasy chemie   MeSH
• bakteriální proteiny chemie   MeSH
• hexosaminidasy chemie   MeSH
• koncentrace vodíkových iontů MeSH
• látky znečišťující půdu analýza   chemie   MeSH
• oxidoreduktasy chemie   MeSH
• popel uhelný chemie   MeSH
• půda chemie   MeSH
• půdní mikrobiologie * MeSH
• regenerace a remediace životního prostředí MeSH
• rtuť analýza   chemie   MeSH
• znečištění životního prostředí MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• arylsulfatasy MeSH
• bakteriální proteiny MeSH
• hexosaminidasy MeSH
• látky znečišťující půdu MeSH
• oxidoreduktasy MeSH
• popel uhelný MeSH
• půda MeSH
• rtuť MeSH