Microbially mediated cadmium sorption/desorption processes in soil amended with sewage sludge

Mobilization of cadmium from festuca ovina roots and its distribution between operational fractions in soil

“…Moreover, positive values of correlation were determined between the amounts of organically bound Cd and bacterial and fungal numbers ( Table 2). This observation confirmed that of earlier studies (Majewska and Kurek 2007) which also showed the significant effect of microbial activity on the changes in distribution of Cd in soils. Thus, in accordance with earlier work, soil organic matter, besides generating bound metal oxides, are an important factor in immobilizing toxic metal in soil (Shaheen et al 2013, Bolan et al 2014).…”

“…2): ion exchangeable (8%), bound to Fe and Mn oxides (42%), organically bound (30%), and residual (20%). The distribution of Cd between tested fractions resembled its distribution as found in the uncontaminated soil (sandy loam, 1 µg Cd g -1 DW) as investigated in previous studies (Majewska and Kurek 2007). On the day of pot transplanting, about 420 µg Cd was found to be present in the grass roots, and this was introduced into 200 g DW of soil.…”

“…Based on ways of their binding by soil constituents and the strength of the created bounds, seven geochemical fractions of metals can be described: (1) a mobile fraction containing soluble and non-specifically sorbed metals, as well as metal-organic complexes, (2) an easily mobilizable fraction including metals specifically sorbed on the particle surface and bound to carbonates, (3) occluded in manganese oxides, (4) bound to soil organic matter, (5) occluded in amorphous iron oxides, (6) occluded in crystalline iron oxides, and (7) structurally bound in soil minerals (Conesa et al 2010, Stritsis et al 2014). Chemical speciation of metals determined in soil changes over time, and their redistribution between operational fractions is possible (Majewska and Kurek 2007, Kabata-Pendias 2011, Oves et al 2012). However, a dynamic equilibrium between the processes of mobilization and immobilization of metals comes about (Bolan et al 2014).…”

Application of grass char for Cd(II) treatment in column leaching test

“…Previous studies have shown the potential of biomass in heavy metal contained wastewater treatment after pyrolysis at increased temperature [6,8,[15][16][17]9]. The sorption affinity and capacity of pyrolysed biomass, which are determined by batch test, appears to be higher than most of the reported sorbents [18].…”

Application of different organic wastes in a soil polluted by cadmium: Effects on soil biological properties

“…The properties influencing the concentration of Cd in the soil aqueous phase include soil pH, redox potential, soil texture, mineral composition (proportion of clays, iron and manganese oxides), cationexchange capacity, the amount and type of soil organic compounds, temperature, moisture content, heavy metal presence (other heavy metals may compete for adsorption sites), and the number and type of microorganisms inhabiting the soil (Leadin, 2000;Kabata-Pendias and Sadurski, 2004;Majewska et al, 2007).…”