Mobility, speciation of cadmium, and bacterial community composition along soil depths during microbial carbonate precipitation under simulated acid rain

TY - JOUR

T1 - Mobility, speciation of cadmium, and bacterial community composition along soil depths during microbial carbonate precipitation under simulated acid rain

AU - Li, Weila

AU - Cai, Yiting

AU - Li, Yilin

AU - Achal, Varenyam

N1 - Publisher Copyright: © 2024 Elsevier Ltd

PY - 2024/2/27

Y1 - 2024/2/27

N2 - An overexploitation of earth resources results in acid deposition in soil, which adversely impacts soil ecosystems and biodiversity and affects conventional heavy metal remediation using immobilization. A series of column experiments was conducted in this study to compare the cadmium (Cd) retention stability through biotic and abiotic carbonate precipitation impacted by simulated acid rain (SAR), to build a comprehensive understanding of cadmium speciation and distribution along soil depth and to elucidate the biogeochemical bacteria-soil-heavy metal interfaces. The strain of Sporosarcina pasteurii DSM 33 was used to trigger the biotic carbonate precipitation and cultivated throughout the 60-day column incubation. Results of soil pH, electrical conductivity (EC), and quantitative CdCO3/CaCO3 analysis concluded that the combination of biotic and abiotic soil treatment could reinforce soil buffering capacity as a strong defense mechanism against acid rain disturbance. Up to 1.8 ± 0.04 U/mg urease enzyme activity was observed in combination soil from day 10, confirming the sustained effect of urease-mediated microbial carbonate precipitation. Cadmium speciation and distribution analyses provided new insights into the dual stimulation of carbonate-bound and Fe/Mn-bound phases of cadmium immobilization under microbially induced carbonate precipitation (MICP). As confirmed by the microbial community analysis, outsourcing urea triggered diverse microbial metabolic responses, notably carbonate precipitation and dissimilatory iron metabolism, in both oxygen-rich topsoil and oxygen-depleted subsurface layers. The overall investigation suggests the feasibility of applying MICP for soil Cd remediation under harsh environments and stratagem by selecting microbial functionality to overcome environmental challenges.

AB - An overexploitation of earth resources results in acid deposition in soil, which adversely impacts soil ecosystems and biodiversity and affects conventional heavy metal remediation using immobilization. A series of column experiments was conducted in this study to compare the cadmium (Cd) retention stability through biotic and abiotic carbonate precipitation impacted by simulated acid rain (SAR), to build a comprehensive understanding of cadmium speciation and distribution along soil depth and to elucidate the biogeochemical bacteria-soil-heavy metal interfaces. The strain of Sporosarcina pasteurii DSM 33 was used to trigger the biotic carbonate precipitation and cultivated throughout the 60-day column incubation. Results of soil pH, electrical conductivity (EC), and quantitative CdCO3/CaCO3 analysis concluded that the combination of biotic and abiotic soil treatment could reinforce soil buffering capacity as a strong defense mechanism against acid rain disturbance. Up to 1.8 ± 0.04 U/mg urease enzyme activity was observed in combination soil from day 10, confirming the sustained effect of urease-mediated microbial carbonate precipitation. Cadmium speciation and distribution analyses provided new insights into the dual stimulation of carbonate-bound and Fe/Mn-bound phases of cadmium immobilization under microbially induced carbonate precipitation (MICP). As confirmed by the microbial community analysis, outsourcing urea triggered diverse microbial metabolic responses, notably carbonate precipitation and dissimilatory iron metabolism, in both oxygen-rich topsoil and oxygen-depleted subsurface layers. The overall investigation suggests the feasibility of applying MICP for soil Cd remediation under harsh environments and stratagem by selecting microbial functionality to overcome environmental challenges.

KW - Bioremediation

KW - Heavy metals

KW - Immobilization

KW - Iron metabolization

KW - Microbial diversity

KW - Urease

UR - http://www.scopus.com/inward/record.url?scp=85184142415&partnerID=8YFLogxK

U2 - 10.1016/j.jenvman.2024.120018

DO - 10.1016/j.jenvman.2024.120018

M3 - 文章

C2 - 38271885

AN - SCOPUS:85184142415

SN - 0301-4797

VL - 353

JO - Journal of Environmental Management

JF - Journal of Environmental Management

M1 - 120018

ER -