Simultaneously decreasing arsenic and cadmium in rice by soil sulfate and limestone amendment under intermittent flooding

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Water management in paddy soils can effectively reduce the soil-to-rice grain transfer of either As or Cd, but not of both elements simultaneously due to the higher mobility of As under reducing and Cd under oxidizing soil conditions. Limestone amendment, the common form of liming, is well known for decreasing Cd accumulation in rice grown on acidic soils. Sulfate amendment was suggested to effectively decrease As accumulation in rice, especially under intermittent soil flooding. To study the unknown effects of combined sulfate and limestone amendment under intermittent flooding for simultaneously decreasing As and Cd in rice, we performed a pot experiment using an acidic sandy loam paddy soil. We also included a clay loam paddy soil to study the role of soil texture in low-As rice production under intermittent flooding. We found that liming not only decreased rice Cd concentrations but also greatly decreased dimethylarsenate (DMA) accumulation in rice. We hypothesize that this is due to suppressed sulfate reduction, As methylation, and As thiolation by liming in the sulfate-amended soil and a higher share of deprotonated DMA at higher pH which is taken up less readily than protonated DMA. Decreased gene abundance of potential soil sulfate-reducers by liming further supported our hypothesis. Combined sulfate and limestone amendment to the acidic sandy loam soil produced rice with 43% lower inorganic As, 72% lower DMA, and 68% lower Cd compared to the control soil without amendment. A tradeoff between soil aeration and water availability was observed for the clay loam soil, suggesting difficulties to decrease As in rice while avoiding plant water stress under intermittent flooding in fine-textured soils. Our results suggest that combining sulfate amendment, liming, and intermittent flooding can help to secure rice safety when the presence of both As and Cd in coarse-textured soils is of concern.

Medienart:

E-Artikel

Erscheinungsjahr:

2024

Erschienen:

2024

Enthalten in:

Zur Gesamtaufnahme - volume:347

Enthalten in:

Environmental pollution (Barking, Essex : 1987) - 347(2024) vom: 15. Apr., Seite 123786

Sprache:

Englisch

Beteiligte Personen:

Fang, Xu [VerfasserIn]
Colina Blanco, Andrea E [VerfasserIn]
Christl, Iso [VerfasserIn]
Le Bars, Maureen [VerfasserIn]
Straub, Daniel [VerfasserIn]
Kleindienst, Sara [VerfasserIn]
Planer-Friedrich, Britta [VerfasserIn]
Zhao, Fang-Jie [VerfasserIn]
Kappler, Andreas [VerfasserIn]
Kretzschmar, Ruben [VerfasserIn]

Links:

Volltext

Themen:

00BH33GNGH
Alternate wetting and drying (AWD)
Arsenic
C7X2M0VVNH
Cadmium
Calcium Carbonate
Calcium Compounds
Clay
Deprotonation
Dimethylarsenate
Food safety
H0G9379FGK
Journal Article
Lime
Methylation
N712M78A8G
Oxides
Sand
Soil
Soil Pollutants
Soil remediation
Soil texture
Sulfates
Sulfur Oxides
T1FAD4SS2M

Anmerkungen:

Date Completed 08.04.2024

Date Revised 08.04.2024

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1016/j.envpol.2024.123786

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM369746538