Use of White Lupin Plant for Phytostabilization of Cd and As Polluted Acid Soil

Abstract

Cadmium and arsenic are two of the most important and toxic pollutants ubiquitous in the environment. The occurrence of numerous polluted areas as the affected by the accident of Aznalcóllar pyrite mine has promoted the employment of the phytoremediation as a feasible technology able to control and reduce the risk of this contamination at low cost. White lupin plant is proposed as a candidate for phytoremediation. This work aims to study if it is possible to use white lupin in phytoremediation of soils affected by acid pyrite sludge, with simultaneous As and Cd pollution. Pot and field experiments with sludge-affected soil were carried out. The pot trial showed that the NTA treatment increased Cd and As concentrations in lixiviates, exceeding the maximum permissible levels, so that its use in field experiments was avoided. In the field experiment, phytoextraction of Cd and As by lupin plants was very low, suggesting that it was not recommended for phytoextraction. However, lupin culture in the field produced several benefits as: increase of acid soil pH probably by citrate excretion, decrease in soluble As and Cd fractions in soil, high concentration of As and Cd in roots with accumulation of heavy metals in root nodules. All these results support the use of Lupinus albus for phytostabilization and revegetation of the spill polluted soils.

Zinc and cadmium accumulation by Lupinus uncinatus Schldl. grown in nutrient solution

“…Overall, the results support the hypothesis that L. uncinatus could be used in the combined strategies to recover Zn-and Cd-contaminated soils. The use of L. uncinatus could associate the advantages of using leguminous plants and the efficiency in phytostabilization (Ehsan et al 2009) as also demonstrated for other trace elements in the case of white lupin (Vazquez et al 2006;Esteban et al 2008) and also in case of other plants such as Viguiera dentata, Parthenium bipinnatifidum, Flaveria angustifolia, F. trinervia, and Sporobolus indicus which could be used to vegetate soils with large amounts of As, Cu, Pb, and Zn (Franco-Hernández et al 2010). Its efficiency in accumulating Cd in the roots, with very low translocation rate to the shoots, could make it a good choice in phytostabilization, preventing leaking of Cd from contaminated soils.…”

“…Some Lupinus species are able to accumulate Zn (Pastor et al 2003), Cd (Brennan and Bolland 2003), Mg and Al (Reay and Waugh 1981), Hg (Vera et al 2002;Esteban et al 2008), and Pb and Cr (Ximenez-Embun et al 2001). Moreover, white lupin (Lupinus albus L.) tolerance to Cd and As with few toxic visual symptoms has been reported (Zornoza et al 2002;Vazquez et al 2005), as well as its ability for phosphateassisted phytoextraction of As (Tassi et al 2004) and for phytostabilization of acidified multi-contaminated soils (Vazquez et al 2006). Ximenez-Embun et al (2001) reported that L. albus, L. luteus, L. angustifolius, and L. hispanicus were able to grow under extreme conditions (wastewater, pH lower than 2) and to remove 98 % of the initial amount of toxic metals present in the sample.…”

Exploring the Potential of Bacteria-Assisted Phytoremediation of Arsenic-Contaminated Soils

“…found that E. cladocalyx had the highest biomass and did not to affect As availability making it a good candidate for phytostabilization of As in gold mine tailings. In an earlier study, Vazquez et al (2006) reported that white lupin reduced Cd and As solubility in the soil while it accumulated significant amounts of the metals in its roots and nodules.…”

“…Although generally, beans are sensitive to metals, some leguminous plants have the capacity to tolerate metals. Lupinus albus was found to be a good candidate for stabilizing As and Cd in soils (Vazquez et al, 2006). Several benefits in using this legume include improvement in soil properties due to atmospheric N fixations, increase in the pH of acidic soils, decrease in CaCl 2 -extractable As and Cd, and retention of these elements in the roots.…”

Using Mediterranean shrubs for the phytoremediation of a soil impacted by pyritic wastes in Southern Spain: A field experiment

“…The experimental plot has been described by Vázquez et al (2006), and has a wide range of pH (2e8), low contents of organic matter (<2%), nitrogen (<0.1) and carbonates (<0.1%) and a loamy-sandy texture.…”