The aim of this study was to investigate the heavy metal effect on enzymatic activity in acidic soil samples during spring, summer, and autumn. The four metal fractions, acid-soluble and exchangeable (F1), reducible (F2), oxidizable (F3), and residual (F4) using BCR method in soil samples, were evaluated. The highest percentage share of zinc and copper was determined in F4 (45.8, 54.9%, respectively) and cadmium in F3 (45.6%). The enzymatic activity in soil was differentiated in seasons. During spring, the significant relationship was noted between F1/zinc/dehydrogenase, during summer F2/cadmium/phosphatase as well as F4/cadmium/dehydrogenase and autumn F3/zinc/dehydrogenase. Fraction F1/zinc/copper influenced phosphatase activity, whereas F3/Zn increased dehydrogenase and F2/Cd protease activity. The results indicate that the heavy metals affected dehydrogenase activity the most.

Total metal content is not representing its availability and thus does not provide the details about potential environmental hazards, including the impact on soil enzyme activities. To understand metal availability, chemical fractions must be considered. The goal of this study was to evaluate the influence of Ni, Cr, and Pb fractions on the enzymatic activity of soils cultivated by the simplified method, which is rare not only in Poland. The percentage of studied metals in fractions was determined according to the Community Bureau of Reference (BCR) method. Four fractions were extracted: acid soluble and exchangeable (F1), reducible (F2), oxidizable (F3), and residual (F4). The highest Ni and Cr percentages were noted in fraction F4, and for Pb, they were noted in fraction F2. The smallest Ni and Pb percentages were observed in fraction F1 (most mobile) and for Cr, they were observed in fraction F2. In soil samples collected in spring, the significant relationship was stated between F1/Ni/dehydrogenase, F2/Pb/dehydrogenase, and F2/Pb/urease. Such dependence occurred between F1/Ni/phosphatase and F4/Ni/urease during summer as well as between F1/Ni/phosphatase and F4/Ni/dehydrogenase in autumn. F1/Pb caused a drop in phosphatase activity, whereas F4/Cr influenced its increase. The study results indicated that metal fractions influenced phosphatase activity the most, while protease activity in the soil was not affected.

In the fresh municipal solid waste incineration (MSWI) of bottom ash, samples the fractional composition of Zn, Cr and Co was investigated. The BCR method was utilised to evaluate the acid soluble and exchangeable fraction (F1), reducible fraction (F2), oxidizable fraction (F3) and residual...