Cadmium Chemical Forms in Two Calcareous Soils Treated with Different Levels of Incubation Time and Moisture Regimes

Abstract

Sequential extraction is used effectively to determine the chemical forms of heavy metals. Since few studies have been conducted in calcareous soils of Iran, the current research has been carried out to evaluate the effect of moisture regimes and incubation time on the chemical forms of cadmium in two calcareous soils. Treatments included three levels of cadmium (0, 30 and 60 mg/kg of soil as CdSo 4), three incubation times (2, 4 and 8 weeks), two soils (clay and sandy clay loam) and two moisture regimes (Waterlogged and Field capacity). The experiment was performed as factorial on the basis of randomized complete blocks design with two replications. At 2, 4, and 8 weeks after treatment, the Tessier et al. (1979) sequential extraction method was applied to measure the cadmium concentration in water soluble-exchangeable (WsEx.), iron and manganese oxide (Fe-MnOx.), carbonate (Car.), organic matter (Om.) and residual forms (Res.). The results showed depending on the soil texture, 68 to 72 percent of the cadmium was in water soluble-exchangeable and iron-manganese oxide forms. Flooding condition decreased the concentration of cadmium in water soluble + exchangeable form and increased the concentration of cadmium in the forms of Fe-Mn oxides, carbonate and organic matter. Concentration of cadmium in residual form was higher in clay soil. In sandy clay loam soil, water soluble-exchangeable, carbonate and organic matter forms were higher than clay soil. The iron-manganese oxides form showed no significant difference in two soils at field capacity regime. In flooding conditions, the concentration of the water soluble-exchangeable form decreased and the concentration of other forms increased. In contrast to the oxidizing conditions at the reduction conditions, no significant difference was observed in the residual and organic matter forms in two soils.

Organic amendment additions to cadmium-contaminated soils for phytostabilization of three bioenergy crops

“…All soil amendments increased Cd accumulation by shoots and roots in jatropha and acacia by factors of up to 1.3 to 1.7 and 1.0 to 1.7, respectively. Cadmium levels in soil, on the other hand, have been demonstrated to increase with time as a result of increased sorption of Cd on OM 23 . Studies have also demonstrated that jatropha can serve as an accumulator for a variety of heavy metals; however, it is not a suitable accumulator for all heavy metals as it accumulates some at only very low quantities in shoots.…”

Impact of polystyrene microplastics on cadmium uptake in corn (Zea mays L.) in a cadmium‐contaminated calcareous soil

“…22,[33][34][35][36] Long-term accumulation of Cd in soil can pose a risk to the food chain and human health. [37][38][39][40][41] Studies have shown that Cd adsorbs onto MPs, and its uptake and accumulation can impact nutrient delivery. 42,43 PS is an aromatic polymer commonly used in various products, including CDs, toys, toothbrushes, and styrofoam.…”

“…Cadmium (Cd) is a highly toxic element that can contaminate soil through various sources, such as aerial deposition, irrigation, fertilizers, pesticides, and industrial waste 22,33–36 . Long‐term accumulation of Cd in soil can pose a risk to the food chain and human health 37–41 . Studies have shown that Cd adsorbs onto MPs, and its uptake and accumulation can impact nutrient delivery 42,43 .…”

Effect of monocalcium phosphate on the concentration of cadmium chemical fractions in two calcareous soils in Iran

“…Temperatures in the climate vary (the mean monthly maximum ranges from 6.30°C to 29.50°C), and November to May is when most rain falls (346 mm on average). The terms xeric and thermic refer to the soil's warmth and moisture (Rassaei et al, 2019a). This region's geology is evidenced by lucostrin deposits, calcareous marls, and gypsiferous marls.…”

“…Sequential extraction is employed effectively to work out the chemical types of heavy metals. By using the extractants which boosts from low acidic extraction solution to high acidic extraction solution we will have some data about the bioavailability of metals and their association with soil components (Rassaei et al, 2019a). One of the most important factors in increasing the yield production is phosphorus fertilizer.…”