Assessment of using bentonite, dolomite, natural zeolite and manure for the immobilization of heavy metals in a contaminated soil: The Copșa Mică case study (Romania)
The research paper investigates the effectiveness of various organic and inorganic amendments—specifically Na-bentonite, dolomite, natural zeolite, and manure—in immobilizing heavy metals (cadmium, lead, and zinc) in contaminated soils, focusing on the Copșa Mică area in Romania. The study is motivated by the increasing threat of heavy metal contamination to soil quality and human health, particularly in agricultural settings.
A field experiment was conducted over two years, where different amendments were applied to assess their impact on soil pH and metal availability. Results indicated that all treatments significantly increased soil pH, with dolomite and Na-bentonite showing the most substantial effects. Following the application of these amendments, there was a notable decrease in the availability of heavy metals compared to control plots, although the extent of reduction varied by metal and amendment type.
The study found that while dolomite and Na-bentonite effectively reduced lead and zinc concentrations in plants, the levels remained insufficient for producing healthy food or fodder. Manure application increased biomass yield but had a moderate effect on metal extractability. The findings highlight the potential of Na-bentonite and dolomite for reducing heavy metal toxicity in contaminated soils, although the authors caution about the temporary nature of these effects and the possibility of metal remobilization over time.
The research paper emphasizes the importance of long-term monitoring and the need for repeated applications of amendments to ensure sustained effectiveness in immobilizing heavy metals in contaminated soils.
This research paper is significant in the field of environmental science and soil remediation, particularly concerning heavy metal contamination. It contributes to ongoing discussions about sustainable agricultural practices and soil health by providing empirical evidence on the effectiveness of various amendments in immobilizing heavy metals. The findings are particularly relevant for regions with historical industrial pollution, offering insights into cost-effective and practical remediation strategies. The study also underscores the need for further research into the long-term effects of these amendments, which can inform policy and management practices aimed at protecting human health and the environment.
