Document Type : Research Paper
Author
Salahhadin University/ Education College/ Biology Department
Abstract
Soil contamination with heavy metals, particularly copper (Cu), poses a significant challenge to environmental health and agricultural. This study evaluates the potential of organic amendments, including walnut shell biochar (produced at 700°C), sunflower husk biochar (produced at 500°C) and nutshell flour, to reduce Cu availability in contaminated soils. The amendments were applied at two concentrations (2.5% and 5%) to soils spiked with 2,000 mg/kg Cu. The untreated control soil exhibited the highest mean Cu availability (342.7 mg/kg), highlighting the severity of contamination. Upon treatment with 2.5% walnut shell biochar, Cu availability decreased significantly to 231.6 mg/kg, while 2.5% sunflower husk biochar, further reduced Cu availability significantly to 222.2 mg/kg. A more substantial reduction was achieved with 2.5% nutshell flour, which lowered Cu availability significantly to 181.4 mg/kg. At the higher application rate (5%), the amendments showed enhanced efficacy. Walnut shell biochar and sunflower husk biochar reduced Cu availability to 223.2 mg/kg and 190.7 mg/kg, respectively. Notably, 5% nutshell flour exhibited the highest immobilization potential, decreasing Cu availability significantly to 142.9 mg/kg. While in other hand study also investigates the effects of walnut shell biochar, sunflower husk biochar, and nutshell flour on the pH of Cu-contaminated soil (2,000 mg/kg Cu), The untreated control soil had a neutral pH of 7.52, while Cu contamination significantly reduced pH to 6.47, reflecting increased acidity. Application of 2.5% and 5% walnut shell biochar and 2.5% sunflower husk biochar significantly elevated the pH to 8.0, 8.21 and 7.96, respectively, achieving near-neutral or slightly alkaline conditions. Conversely, 2.5% nutshell flour resulted in a marginal pH increase to 6.59, indicating limited neutralizing potential.
Keywords
Main Subjects
- Alloway BJ. 2013. Sources of heavy metals and metalloids in soils. Heavy metals in soils: trace metals and metalloids in soils and their bioavailability:11-50 https://doi.org/10.1007/978-94-007-4470-7_2
- He ZL, Yang XE, Stoffella PJ. 2005. Trace elements in agroecosystems and impacts on the environment. Journal of Trace elements in Medicine and Biology 19:125-40
https://doi.org/10.1016/j.jtemb.2005.02.010 - Minkina TM, Fedorenko GM, Nevidomskaya DG, Pol’shina TN, Fedorenko AG, et al. 2021. Bioindication of soil pollution in the delta of the Don River and the coast of the Taganrog Bay with heavy metals based on anatomical, morphological and biogeochemical studies of macrophyte (Typha australis Schum. & Thonn). Environmental Geochemistry and Health 43:1563-81
https://doi.org/10.1007/s10653-019-00379-3 - Shruthi K, Pavithra M. 2018. A study on utilization of groundnut shell as biosorbent for heavy metals removal. International Journal of Engineering and Technology 4:411-5.
- Witek-Krowiak A, Szafran RG, Modelski S. 2011. Biosorption of heavy metals from aqueous solutions onto peanut shell as a low-cost biosorbent. Desalination 265:126-34 https://doi.org/10.1016/j.desal.2010.07.042
- Qaiser S, Saleemi AR, Umar M. 2009. Biosorption of lead (II) and chromium (VI) on groundnut hull: Equilibrium, kinetics and thermodynamics study. Electronic journal of Biotechnology 12:3-4
https://doi.org/10.2225/vol12-issue4-fulltext-6 - Liang L, Liu W, Sun Y, Huo X, Li S, Zhou Q. 2017. Phytoremediation of heavy metal contaminated saline soils using halophytes: current progress and future perspectives. Environmental Reviews 25:269-81 https://doi.org/10.1139/er-2016-0063
- Ali H, Khan E, Sajad MA. 2013. Phytoremediation of heavy metals—concepts and applications. Chemosphere 91:869-81 https://doi.org/10.1016/j.chemosphere.2013.01.075
- Park JH, Choppala GK, Bolan NS, Chung JW, Chuasavathi T. 2011. Biochar reduces the bioavailability and phytotoxicity of heavy metals. Plant and soil 348:439-51 https://doi.org/10.1007/s11104-011-0948-y
- Ahmad M, Rajapaksha AU, Lim JE, Zhang M, Bolan N, et al. 2014. Biochar as a sorbent for contaminant management in soil and water: a review. Chemosphere 99:19-33
https://doi.org/10.1016/j.chemosphere.2013.10.071 - Chao X, Qian X, Han-Hua Z, Shuai W, Qi-Hong Z, et al. 2018. Effect of biochar from peanut shell on speciation and availability of lead and zinc in an acidic paddy soil. Ecotoxicology and environmental safety 164:554-61 https://doi.org/10.1016/j.ecoenv.2018.08.057
- Zha Y, Zhao L, Wei J, Niu T, Yue E, et al. 2023. Effect of the application of peanut shell, bamboo, and maize straw biochars on the bioavailability of Cd and growth of maize in Cd-contaminated soil. Frontiers in Environmental Science 11:1240633 https://doi.org/10.3389/fenvs.2023.1240633
- Ryan J, Estefan G, Rashid A. 2001. Soil and plant analysis laboratory manual. ICARDA.
- Bakshi S, He ZL, Harris WG. 2014. Biochar amendment affects leaching potential of copper and nutrient release behavior in contaminated sandy soils. Journal of environmental quality 43:1894-902
https://doi.org/10.2134/jeq2014.05.0213 - Meier S, Curaqueo G, Khan N, Bolan N, Cea M, et al. 2017. Chicken-manure-derived biochar reduced bioavailability of copper in a contaminated soil. Journal of Soils and Sediments 17:741-50
https://doi.org/10.1007/s11368-015-1256-6 - Yang W, Pan Y, Yu X, Xiao S, Wang W, Lu M. 2022. Biochar & cropping systems changed soil copper speciation and accumulation in Sweet Corn and Soybean. Plants 11:2375
https://doi.org/10.3390/plants11182375 - Salam A, Bashir S, Khan I, Shahid Rizwan M, Afzal Chhajro M, et al. 2018. Biochars immobilize lead and copper in naturally contaminated soil. Environmental Engineering Science 35:1349-60
https://doi.org/10.1089/ees.2018.0086 - Lehmann J, Joseph S. 2024. Biochar for environmental management: science, technology and implementation. Taylor & Francis.
- Verheijen F, Jeffery S, Bastos A, Van der Velde M, Diafas I. 2009. Biochar application to soil-a critical scientific review of effects on soil properties, processes and functions. EUR 24099:149pp.
- Yao Y, Gao B, Zhang M, Inyang M, Zimmerman AR. 2012. Effect of biochar amendment on sorption and leaching of nitrate, ammonium, and phosphate in a sandy soil. Chemosphere 89:1467-71
https://doi.org/10.1016/j.chemosphere.2012.06.002 - Xu C, Chen H-x, Xiang Q, Zhu H-h, Wang S, et al. 2018. Effect of peanut shell and wheat straw biochar on the availability of Cd and Pb in a soil–rice (Oryza sativa L.) system. Environmental Science and Pollution Research 25:1147-56 https://doi.org/10.1007/s11356-017-0495-z.
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