Goethite modified biochar simultaneously mitigates the arsenic and cadmium accumulation in paddy rice (Oryza sativa) L

Muhammad Kashif Irshad; Ali Noman; Yang Wang; Yingjie Yin; Chong Chen; Jianying Shang

doi:10.1016/j.envres.2021.112238

Goethite modified biochar simultaneously mitigates the arsenic and cadmium accumulation in paddy rice (Oryza sativa) L

Environ Res. 2022 Apr 15:206:112238. doi: 10.1016/j.envres.2021.112238. Epub 2021 Oct 21.

Authors

Muhammad Kashif Irshad¹, Ali Noman², Yang Wang³, Yingjie Yin³, Chong Chen³, Jianying Shang⁴

Affiliations

¹ College of Land Science and Technology, China Agricultural University, Beijing, China; Department of Environmental Sciences and Engineering, Government College University Faisalabad, Pakistan.
² Department of Botany, Government College University Faisalabad, Pakistan.
³ College of Land Science and Technology, China Agricultural University, Beijing, China.
⁴ College of Land Science and Technology, China Agricultural University, Beijing, China. Electronic address: jyshang@cau.edu.cn.

PMID: 34688646
DOI: 10.1016/j.envres.2021.112238

Abstract

Cadmium (Cd) and arsenic (As) contamination of paddy soils is a serious global issue because of the opposite geochemical behavior of Cd and As in paddy soils. Rice plant (Oryza sativa L.) cultivation in Cd- and As- contaminated paddy soil is regarded as one of the main dietary cause of Cd and As entry in human beings. This study aimed to determine the impact of goethite-modified biochar (GB) on bioavailability of both Cd and As in Cd- and As- polluted paddy soil. Contrary to control and biochar (BC) amendments, the application of GB amendments significantly impeded the accumulation of both Cd and As in rice plants. The results confirmed an obvious reduction in Cd and As content of rice grains by 85% and 77%, respectively after soil supplementation with GB 2% amendment. BC 3% application minimized the Cd uptake by 59% in the rice grains as compared to the control but exhibited a little impact on As accumulation in rice grains. Sequential extraction results displayed an increase in immobile Cd and As fractions of the soil by decreasing the bioavailable fractions of both elements after GB treatments. Fe-plaque formation on the root surfaces was significantly variable (P ˂ 0.05) among all the amendments. GB 2% treatment significantly increased the Fe content (10 g kg^-1) of root Fe-plaque by 48%, which ultimately enhanced the sequestration of Cd and As by Fe-plaque and minimized the transport of Cd and As in rice plants. Moreover, GB treatments significantly changed the relative abundance of the microbial community in the rice rhizosphere and minimized the metal(loid)s mobility in the soil. The relative abundance of Acidobacteria, Firmicutes and Verrucomicrobia increased with GB 2% treatment while those of Bacteroidetes and Choloroflexi decreased. Our findings confirmed improvement in the rice grains quality regarding enhanced amino acid contents with GB application. Overall, the results of this study demonstrated that GB amendment simultaneously alleviated the Cd and As concentrations in edible parts of rice plant and provided a new valuable method to protect the public health by effectively remediating the co-occurrence of Cd and As in paddy soils.

Keywords: Fe-plaque; Metal(loid)s; Oryza sativa L.; Paddy soil; Soil microbes.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Arsenic* / analysis
Cadmium / analysis
Charcoal
Humans
Iron Compounds
Minerals
Oryza* / chemistry
Soil / chemistry
Soil Pollutants* / analysis

Substances

Iron Compounds
Minerals
Soil
Soil Pollutants
biochar
Cadmium
goethite
Charcoal
Arsenic