Temporal and spatial differentiation characteristics of soil arsenic during the remediation process of Pteris vittata L. and Citrus reticulata Blanco intercropping

Yunxian Yan; Jun Yang; Xiaoming Wan; Huading Shi; Junxing Yang; Chuang Ma; Mei Lei; Tongbin Chen

doi:10.1016/j.scitotenv.2021.152475

Temporal and spatial differentiation characteristics of soil arsenic during the remediation process of Pteris vittata L. and Citrus reticulata Blanco intercropping

Sci Total Environ. 2022 Mar 15:812:152475. doi: 10.1016/j.scitotenv.2021.152475. Epub 2021 Dec 21.

Authors

Yunxian Yan¹, Jun Yang², Xiaoming Wan¹, Huading Shi³, Junxing Yang¹, Chuang Ma⁴, Mei Lei¹, Tongbin Chen¹

Affiliations

¹ Center for Environmental Remediation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China.
² Center for Environmental Remediation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China. Electronic address: yangj@igsnrr.ac.cn.
³ Technical Centre for Soil, Agricultural and Rural Ecology and Environment, Ministry of Ecology and Environment, Beijing 100012, China.
⁴ Henan Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration, Zhengzhou University of Light Industry, Zhengzhou 450000, China.

PMID: 34952060
DOI: 10.1016/j.scitotenv.2021.152475

Abstract

The intercropping of hyperaccumulators and fruit trees has great application prospects owing to its environmental and economic benefits. However, the variation tendency and spatial distribution characteristics of pollutants in soil are unclear. A 19-month pot positioning experiment was conducted to clarify the spatio-temporal characteristics of arsenic (As) during Pteris vittata L.-Citrus reticulata Blanco intercropping process. The results showed that: (1) In the early stage, the solubilization of soil As by P. vittata was dominant. At 3 months, the water-soluble As in P. vittata rhizosphere soil increased by 19.4-55.4% compared with the initial state. In the later stage, the As extraction from soil by P. vittata was dominant. At 19 months, the water-soluble As in P. vittata rhizosphere soil decreased by 24.6-71.2% compared with the initial state. The water-soluble As in C. reticulata rhizosphere soil in intercropping, under the role of P. vittata, reached 1.75-2.35 times that of monoculture at 7 months, and was not significantly different from that of monoculture at 19 months. (2) The spatial distribution characteristics of soil As, affected by As-hyperaccumulation of P. vittata, showed that the As variability of intercropping and P. vittata monoculture was greater than that of C. reticulata monoculture. The area of P. vittata remediating soil was approximately 15 cm horizontally around its planting point and at least 25 cm vertically. (3) P. vittata-C. reticulata intercropping did not affect the phytoremediation efficiency and effectively reduced the risk of As pollution for C. reticulata. The As concentration in C. reticulata leaves of open intercropping decreased by 39.0-64.2% (early-maturity) and 25.6-59.1% (late-maturity) compared with that of monoculture, similar to that in clean soil. This study analyzed the As migration characteristics during P. vittata-C. reticulata intercropping through time and space and provides important theoretical support for the remediation and safe use of As-contaminated farmland.

Keywords: Arsenic; Hyperaccumulator; Intercropping mode; Pteris vittata L.; Rhizosphere soil.

MeSH terms

Arsenic* / analysis
Biodegradation, Environmental
Citrus*
Pteris*
Soil
Soil Pollutants* / analysis

Substances

Soil
Soil Pollutants
Arsenic