Chemodiversity of dissolved organic matter in cadmium-contaminated paddy soil amended with different materials.
Sci Total Environ
; 825: 153985, 2022 Jun 15.
Article
in En
| MEDLINE
| ID: mdl-35189242
ABSTRACT
Dissolved organic matter (DOM) in soil is a key factor affecting the bioavailability of heavy metals, but very few studies have focused on the role of DOM in the use of soil amendments to mitigate heavy metal accumulation in crops. Here, eleven materials were added to cadmium (Cd)-contaminated paddy soil in greenhouse pot trials; rice was grown and harvested, the chemodiversity of post-harvest soil DOM was characterized using Fourier-Transform Ion Cyclotron Resonance Mass Spectrometry, and the specific associations between soil DOM traits and water-extractable soil Cd concentration were identified at the molecular level. The results showed that the endogenous release caused by altering soil pH had a greater effect on soil DOM concentration than did the exogenous chemical input due to the application of organic amendments, which in turn contributed to the chemodiversity of DOM. After one season of rice cultivation, soil DOM molecules were mainly dominated by relatively low molecular weight heteroatom-free lignins. C/N, C/H ratios of organic materials influenced DOM molecular fingerprint patterns, and soil pH and redox potential were the main driving forces affecting the chemodiversity of DOM. Furthermore, the low molecular weight, high saturation, low aromaticity, and heteroatom-free DOM molecules are more likely to dissolve Cd from the soil solid phase, thus increasing the potential risk of Cd to the environment. The results provide critical information about amendments-induced changes in DOM chemodiversity and will inform the selection of appropriate soil amendments.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Oryza
/
Soil Pollutants
/
Metals, Heavy
Type of study:
Prognostic_studies
Language:
En
Journal:
Sci Total Environ
Year:
2022
Document type:
Article
Affiliation country: