The use of indigenous plant species and calcium phosphate for the stabilization of highly metal-polluted sites in southern Poland

Abstract

Highly metal-polluted (Pb, Cd, Zn) soil from a non-ferrous mine and smelter site in southern Poland, further referred to as ''Waryn´ski'' soil, was used to test indigenous plant species for stabilization effectiveness of heavy metals in soils. Results of pilot investigations with commercially available cultivars of plant species showed that these cultivars could not grow on this highly polluted soil even with the application of soil amendments to stabilize the heavy metals. Based on these results, mesocosm and field experiments with an indigenous, metal-tolerant ecotype of Deschampsia cespitosa from the Warynski site were carried out. The mesocosm experiment showed that applications of calcium phosphate (3.8% w/w) as a heavy metal-stabilizing amendment decreased Cd and Zn concentrations 2 and 3-fold respectively in leachates, whereas lead content was not significantly changed. This decrease in the concentration of heavy metals in leachates was correlated with a lower accumulation of Pb, Cd and Zn in the roots and shoots of D. cespitosa, ecotype Warynski. In the field experiment, lower accumulations of Cd in roots and shoots and Zn in shoots in the amendment added plot were observed during the second year of investigations. In the first growing season, D. cespitosa plant cover in the amendment enriched mesocosms ranged from 95 to 100%, compared to 10% in mesocosms without calcium phosphate. In the second year of the experiment, in non-amendment enriched mesocosms D. cespitosa was substituted with Cardaminopsis arenosa (95% cover). C. arenosa is an undesirable species for phytostabilization, as it accumulates high amounts of zinc and cadmium in its shoots, even thought it provided better growth cover in not amended soils. However, in amended mesocosms, soil surface cover by D. cespitosa was still very high (90%). Similar results were obtained in field experiments. Addition of calcium phosphate to the soil also resulted in excellent D. cespitosa root system development when compared to soils without amendment. In amended mesocosms, high plant cover and root system development significantly decreased the volume of leachates and improved water retention. These results indicate that the use of D. cespitosa, ecotype Waryn´ski in combination with calcium phosphate as a heavy metals immobilizing agent is sufficient to restore a dense vegetative cover to highly heavy metal-polluted soil.

The Rengen Grassland Experiment: soil contamination by trace elements after 65 years of Ca, N, P and K fertiliser application

“…A decrease in the mobility of Cd, Zn and Pb in limed soil and an effective decrease in the uptake of these elements by several crops has been investigated and confirmed in pot experiments and under field conditions (Lee et al 2004;Kucharski et al 2005;Castaldi et al 2005). In long-term field experiments (from 15 to 63 years) Gavi et al (1997) also observed a more apparent effect of soil pH on the mobility of Cd compared to N and P fertilisation.…”

Ecotoxicological and microbiological characterization of soils from heavy-metal- and hydrocarbon-contaminated sites

“…The primary minerals of concern were zinc, lead and cadmium ore, dolomite, silt, and grave. The enterprise operated for 70 years, and in 1989, production was closed down, and activities toward the revitalization of 460 ha property were started (Kucharski et al 2005). The area of concern is situated in the immediate vicinity of the former smelter.…”

Predicting the Phytoextraction Duration to Remediate Heavy Metal Contaminated Soils

“…A loamy sandy soil collected from the 0-20 cm soil layer at the Waryński smelter site, an abandoned industrial site near Katowice located in the south-central part of Poland, was used as a source of Cd, Pb, and Zn contaminated soil (see Kucharski et al (2005) for a site description). An uncontaminated, sandy soil was sampled from the plough layer (0-25 cm) of arable land cropped with forage maize (Zea mays L.) near Sellingen located in the north of the Netherlands.…”

“…However, for soils directly affected by mine and ore processing waste, this is more difficult, because these matrices can in fact not be considered as soil, and comparable, uncontaminated matrices are difficult to find. On the other hand, these matrices are usually heavily contaminated with HMs (e.g., Kucharski et al, 2005) and less appropriate for phytoextraction, due to the very long phytoextraction duration needed to complete remediation (Robinson et al, 1998;Zhao et al, 2003).…”

“…Under natural conditions without soil amendments to decrease the availability of HMs, plant growth in the soil from Katowice is severely hampered due to phytotoxic levels of HMs (Kucharski et al, 2005). To create a moderate degree of HM contamination, a relatively small amount of contaminated soil was mixed with a relatively large amount of uncontaminated soil.…”