Do soil amendments used to improve agricultural productivity have consequences for soils contaminated with heavy metals?
Kaninga, Belinda; Chishala, Benson H.; Maseka, Kakoma K.; Sakala, Godfrey M.; Young, Scott D.; Lark, R. Murray; Tye, Andrew; Hamilton, Elliott M.; Gardner, Amanda; Watts, Michael J.. 2020 Do soil amendments used to improve agricultural productivity have consequences for soils contaminated with heavy metals? Heliyon, 6 (11), e05502. 10.1016/j.heliyon.2020.e05502
Before downloading, please read NORA policies.Preview |
Text (Open Access Paper)
1-s2.0-S2405844020323458-main.pdf - Published Version Available under License Creative Commons Attribution 4.0. Download (1MB) | Preview |
Abstract/Summary
This study presents an analysis of the effects of manure and lime commonly used to improve agricultural productivity and evaluates the potential for such soil amendments to mobilise/immobilise metal fractions in soils contaminated from nearby mine tailings in the Zambian Copperbelt. Lime and manure were applied at the onset of the study, and their effects were studied over two planting seasons, i.e. 2016-17 and 2017–18. Operationally defined plant-available Cd, Cu, Ni, Pb and Zn in the soil, were determined by extraction with DTPA-TEA (diethylenetriaminepentaacetic acid-triethanolamine) and 0.01 M Ca(NO3)2, before, and after, applying the amendments. In unamended soils, Cd was the most available and Ni the least. Lime application decreased extractable Cd, Cu, Ni, Pb and Zn. The response to lime was greater in soils with an initially acidic pH than in those with approximately neutral pH values. Manure increased DTPA extractable Zn, but decreased DTPA and Ca(NO3)2 extractable Cd, Cu and Pb. Combined lime and manure amendment exhibited a greater reduction in DTPA extractable Cd, Ni, Pb, Zn, as well as for Ca(NO3)2 extractable Cd compared to separate applications of lime and manure. The amendments had a significant residual effect on most of the soil fractions between season 1 and 2. The results obtained in this study showed that soil amendment with minimal lime and manure whilst benefiting agricultural productivity, may significantly reduce the mobility or plant availability of metals from contaminated agricultural soils. This is important in contaminated, typical tropical soils used for crop production by resource poor communities affected by mining or other industrial activities.
Item Type: | Publication - Article |
---|---|
Digital Object Identifier (DOI): | 10.1016/j.heliyon.2020.e05502 |
ISSN: | 24058440 |
Date made live: | 28 Apr 2021 12:40 +0 (UTC) |
URI: | https://nora.nerc.ac.uk/id/eprint/530181 |
Actions (login required)
View Item |
Document Downloads
Downloads for past 30 days
Downloads per month over past year