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ARS Home » Northeast Area » Beltsville, Maryland (BARC) » Beltsville Agricultural Research Center » Sustainable Perennial Crops Laboratory » Research » Publications at this Location » Publication #380542

Research Project: Characterizing and Evaluating the Genetic Diversity and Horticultural Value of Genetic Resources for Cacao and Other Tropical tree crops Economically important to the United States

Location: Sustainable Perennial Crops Laboratory

Title: Comparative effectiveness of activated dolomite phosphate rock and biochar for immobilizing cadmium and lead in soils

item LIU, BEIBER - University Of Florida
item HE, ZHENLI - University Of Florida
item LIU, RULIANG - University Of Florida
item MONTENEGRO, ANDREA - Colombian Corporation Of Agriculture And Livestock- Agrosavia
item ELLIS, MARTIN - Green Carbon Solutions
item LI, QINFEN - Chinese Academy Of Tropical Agricultural Sciences
item Baligar, Virupax

Submitted to: Chemosphere
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/2/2020
Publication Date: 12/4/2020
Citation: Liu, B., He, Z., Liu, R., Montenegro, A.C., Ellis, M., Li, Q., Baligar, V.C. 2020. Comparative effectiveness of activated dolomite phosphate rock and biochar for immobilizing cadmium and lead in soils. Chemosphere.

Interpretive Summary: Soil pollution by toxic metal (loid)s (TMs) is a serious environmental and a human health issue especially in sandy soils due to their low nutrient retention capacity which makes these soils more vulnerable to TM pollution. In this paper we report our findings that activated dolomite rock phosphate (ADPR) has greater potentials than biochar for remediating toxic levels of cadmium and lead in contaminated sandy soils. This information will be useful to researchers and soil pollution remediation workers to develop technology to remediate contaminated soils there by reducing the entry of toxic metals into the food chain.

Technical Abstract: Sandy soils in Florida are vulnerable to toxic metal pollution, and it is necessary to identify desirable amendments for the remediation of metal contaminated soils. Sorption and incubation experiments were conducted to compare the effectiveness of dolomite phosphate rock (DPR), humic acid activated dolomite phosphate rock (ADPR) and biochar (BC) in immobilizing Cd2+ and Pb2+ in two representative agricultural soils in south Florida (Alfisol-Riviera and Spodosol -Ankona series). The results showed that the soils had a low sorption capacity for metals with maximum sorption of 0.767-3.30 mg/g. Application of amendments increased the maximum sorption by 4.2-4.8 times for Pb2+ and1.5-2.2 times for Cd2+ in Alfisol soil, and 7.1-7.9 times for Pb2+ and 1.7-3.1 times for Cd2+ in Spodosol soil. ADPR was the most effective amendment for increasing the soil’s sorption capacity for Cd2+ and Pb2+. 0.01 M CaCl2 extractable metals in the contaminated soils were significantly decreased by all the amendments, especially ADPR, which reduced extractable Cd2+ and Pb2+by 87.2 and 76.0% in Alfisol and 91.3 and 76.3% in Spodosol soil as compared to control. The amounts of extractable Cd2+ and Pb2+ were negatively correlated with soil pH and available P, indicating that the change of soil characteristics by amendments was the dominant mechanism for enhanced immobilization of metals in the contaminated soils. These results indicate that ADPR has great potential for remediating toxic levels of Cd2+ and Pb2+ in contaminated soils.