Influence of organic and inorganic passivators on Cd and Pb stabilization and microbial biomass in a contaminated paddy soil
- 229 Downloads
Soil contamination with heavy metals, such as Cd and Pb, has caused severe health and environmental risks all over the world. Possible eco-friendly solutions for Cd and Pb immobilization were required to reduce its mobility through various cost-effective amendments.
Materials and methods
A laboratory incubation study was conducted to assess the efficiency of biochar (BC), zeolite (ZE), and rock phosphate (RP) as passivators for the stabilization of Cd and Pb in paddy soil as well as soil microbial biomass. Various extraction techniques were carried out: a sequential extraction procedure, the European Community Bureau of Reference (BCR), toxicity characteristic leaching procedure (TCLP) test, and single extraction with CaCl2. The impact of passivators on soil pH, dissolved organic carbon (DOC), and microbial biomass (carbon, nitrogen, and phosphorus) was examined in the metal contaminated soil.
Results and discussion
The results showed that the exchangeable portion of Cd in soil was significantly reduced by 34.8, 21.6, and 18.8% with ZE, RP, and BC at a 3% application rate, respectively. A similar tendency of reduction in Pb soluble portion was observed by ZE (9.6%), RP (20%), and BC (21.4%) at a 3% application rate. Moreover, the TCLP leachate of Cd and Pb was apparently reduced by 17 and 30.3% with BC at a 3% application dose, respectively, when compared to the control. Soil pH, nutrients, and microbial biomass C, N, and P were significantly increased with the addition of BC, RP, and ZE passivators.
The results showed that the incorporation of BC, ZE, and RP significantly reduced the Cd and Pb mobility in paddy soil as well as enhanced soil nutrients and microbial biomass. Overall, among all the amendments, rice straw derived-BC performed better for Cd and Pb immobilization in paddy soil.
KeywordsBiochar Heavy metals Immobilization Microbial biomass Rock phosphate Zeolite
The study was financially supported by National Science and Technology Support Plan of China (2015BAD05B02).
- Bashir S, Hussain Q, Akmal M, Riaz M, Hu HQ, Ijaz SS, Iqbal M, Abro S, Mehmood S, Ahmad M (2018a) Sugarcane bagasse-derived biochar reduces the cadmium and chromium bioavailability to mash bean and enhances the microbial activity in contaminated soil. J Soils Sediments 18:874–886CrossRefGoogle Scholar
- Bashir S, Zhu J, Fu Q, Hu HQ (2018c) Comparing the adsorption mechanism of Cd by rice straw pristine and KOH modified biochar. Environ Sci Pollut Res. https://doi.org/10.1007/S11356-018-1292-Z
- Frišták V, Pipíška M, Lesny J, Soja G, Friesl-Hanl W, Packová A (2015) Utilization of biochar sorbents for Cd2+, Zn2+, and Cu2+ ions separation from aqueous solutions: comparative study. Environ Monit 9:14–40Google Scholar
- Gee GW, Bauder JW, Klute A (1986) USA. Particle-size analysis. Methods of soil analysis. Part 1. Phys Mineral Method 9:383–411Google Scholar
- Houben D, Evrard L, Sonnet P (2013) Mobility, bioavailability and pH dependent leaching of cadmium, zinc and lead in a contaminated soil amended with biochar. Chemosphere 92:1450–1457Google Scholar
- Liang XF, Han J, Xu YM, Sun YB, Wang L, Tan X (2014) In situ field-scale remediation of Cd polluted paddy soil using sepiolite and palygorskite. Geoderma 9–18:235–236Google Scholar
- Lu RK (2000) Methods of inorganic pollutants analysis. In: Soil and agro-chemical analysis methods. Agricultural Science and Technology Press, Beijing, pp 205–266Google Scholar
- Mohamed I, Zhang G, Li Z, Liu Y, Chen F, Dai K (2015) Ecological restoration of an acidic Cd contaminated soil using bamboo biochar application. Ecol Eng 84:67–76Google Scholar
- Querol X, Alastuey A, Moreno N, Alvarez-Ayuso E, Garcia-Sanchez A, Cama J, Ayora C, Simon M (2006) Immobilization of heavy metals in polluted soils by the addition of zeolitic material synthesized from coal fly ash. Chemosphere, 62:171–180Google Scholar
- Shaaban M, Abid M, Qi-An P (2013) Short term influence of gypsum, farm manure and commercial humic acid on physical properties of salt affected soil in rice paddy system. J Chem Soc Pak 35:1034–1040Google Scholar
- Shaheen SM, Rinklebe J, Selim HM (2015) Impact of various amendments on the bioavailability and immobilization of Ni and Zn in a contaminated floodplain soil. Inter J Environ Sci Techn, 12:2765–2776Google Scholar
- USEPA (1992) Test methods for evaluating solid waste, physical/ chemical methods. US Environmental Pollution Agency USA, Washington, DCGoogle Scholar
- Zin ZZ, Zulkifli H, Tarmizi AM, Hamadan AB, Khalid Raja ZRO (2005) Rock phosphate fertilizers recommended for young oil palm planted on inland soils. MPOB Information Series, ISSN 1511-7871. Malaysian Palm Oil Board, Ministry of Plantation Industries and Commodities, MalaysiaGoogle Scholar