Back to Search
Start Over
Long-Term Manure Application Changes Bacterial Communities in Rice Rhizosphere and Arsenic Speciation in Rice Grains.
- Source :
-
Environmental science & technology [Environ Sci Technol] 2021 Feb 02; Vol. 55 (3), pp. 1555-1565. Date of Electronic Publication: 2021 Jan 15. - Publication Year :
- 2021
-
Abstract
- Bioavailability and speciation of arsenic (As) are impacted by fertilization and bacteria in the rice rhizosphere. In this study, we investigated the effects of long-term manure application on As bioavailability, microbial community structure, and functional genes in a rice paddy field. The results showed that manure application did not affect total As in the soil but increased soluble As forms by 19%, increasing arsenite (As(III)) accumulation in rice grains and roots by 34 and 64% compared to a control. A real-time quantitative polymerase chain reaction (qPCR) and high-throughput sequencing analysis demonstrated that manure application increased the relative abundance of Rhizobium , Burkholderia , Sphingobium , and Sphingomonas containing arsenate reductase genes ( arsC ) in the rhizosphere soil, consistent with the 529% increase in arsC , which may have promoted arsenate (As(V)) reduction and increased As availability in pore water. In addition, manure application significantly altered the iron (Fe)-plaque microbial community structure and diversity. The microbes, particularly, Bradyrhizobium , Burkholderia , and Ralstonia , were mostly associated with As, Fe, and sulfur (S) cycles. This result was consistent with changes in the functional genes related to As, Fe, and S transformation. Although manure application promoted As(V) reduction ( arsC) in Fe-plaque by 682%, it inhibited Fe and S reduction by decreasing Fe <superscript>III</superscript> reduction bacteria (Geobacteraceae) and the sulfate-reducing gene ( dsrA ) abundance. Further, manure application changed the composition of the microbial community that contained the arsC gene. In short, caution needs to be excised even in the soil with a low As concentration as manure application increased As(III) accumulation in rice grains.
Details
- Language :
- English
- ISSN :
- 1520-5851
- Volume :
- 55
- Issue :
- 3
- Database :
- MEDLINE
- Journal :
- Environmental science & technology
- Publication Type :
- Academic Journal
- Accession number :
- 33449628
- Full Text :
- https://doi.org/10.1021/acs.est.0c03924