Issue 8, 2021, Issue in Progress

Effects of amendments on the bioavailability, transformation and accumulation of heavy metals by pakchoi cabbage in a multi-element contaminated soil

Abstract

This study aims to assess the effect of green waste compost (GWC), biochar (BC) and humic acid (HA) amendments of an alkaline heavy metal-contaminated soil. In this study, amendments with GWC, GWC + BC and GWC + HA were applied to the heavy metal-contaminated soil in four application rates (0, 1, 2 and 5%), and was aimed at substantially mitigating the bioavailability of heavy metals for pakchoi cabbage from the sewage irrigation soils. The addition of different ratios of amendments can increase the pH of the soil by 0.11–0.30 units and also increase the organic matter content by 3.1–35.1%. The concentration of available arsenic (As), cadmium (Cd), zinc (Zn) and copper (Cu) in the CaCl2 extract was decreased effectively by all the amendments, except for the increase in the available concentration of As by compost–humic acid (T8) in the soil. Compared with the control, the CaCl2 extractable Cd was decreased by 33–48% after the addition of different ratios of amendments in the soil. Moreover, by increasing the content of compost and compost–biochar in combinations, easily exchangeable fractions of As, Cd, Zn and Cu were decreased, while the oxidation fraction and residual fractions were increased. When the soil amendments were applied, fresh weight of the root and shoot increased by 29–63% and 39–85%, respectively. Cd concentration in the roots and shoots of the pakchoi cabbage decreased by 21–44% and 26–53%, respectively, after adding different ratios of amendments. All the amendments were effective in reducing the Cd, Zn and Cu uptake by the roots and shoots of the pakchoi cabbage, and simultaneously reduce the absorption of As in the roots of pakchoi cabbage. As soil amendments, GWC alone or GWC + BC/GWC + HA application can significantly reduce the heavy metal levels in pakchoi cabbage while increasing the biomass production and higher application rate is more effective than the lower application rate.

Graphical abstract: Effects of amendments on the bioavailability, transformation and accumulation of heavy metals by pakchoi cabbage in a multi-element contaminated soil

Article information

Article type
Paper
Submitted
03 Nov 2020
Accepted
23 Dec 2020
First published
22 Jan 2021
This article is Open Access
Creative Commons BY-NC license

RSC Adv., 2021,11, 4395-4405

Effects of amendments on the bioavailability, transformation and accumulation of heavy metals by pakchoi cabbage in a multi-element contaminated soil

S. Li, X. Sun, S. Li, Y. Liu, Q. Ma and W. Zhou, RSC Adv., 2021, 11, 4395 DOI: 10.1039/D0RA09358K

This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence. You can use material from this article in other publications, without requesting further permission from the RSC, provided that the correct acknowledgement is given and it is not used for commercial purposes.

To request permission to reproduce material from this article in a commercial publication, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party commercial publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements