Unveiling a New Perspective on Cadmium-Induced Hormesis in Soil Enzyme Activity: The Relative Importance of Enzymatic Reaction Kinetics and Microbial Communities

Junyang Wu, Zhongwei Wu, Evgenios Agathokleous, Yongli Zhu, Diwu Fan () and Jiangang Han ()
Additional contact information
Junyang Wu: College of Ecology and Environment, Nanjing Forestry University, No. 159 Longpan Road, Nanjing 210037, China
Zhongwei Wu: College of Ecology and Environment, Nanjing Forestry University, No. 159 Longpan Road, Nanjing 210037, China
Evgenios Agathokleous: Key Laboratory of Agrometeorology of Jiangsu Province, Institute of Ecology, School of Ecology and Applied Meteorology, Nanjing University of Information Science & Technology (NUIST), Nanjing 210044, China
Yongli Zhu: College of Ecology and Environment, Nanjing Forestry University, No. 159 Longpan Road, Nanjing 210037, China
Diwu Fan: College of Ecology and Environment, Nanjing Forestry University, No. 159 Longpan Road, Nanjing 210037, China
Jiangang Han: School of Chemical Engineering and Materials, Changzhou Institute of Technology, No. 666 Liaohe Road, Changzhou 213032, China

Agriculture, 2024, vol. 14, issue 6, 1-19

Abstract: Hormesis in soil enzymes is well-established, yet the underlying mechanism remains elusive. In this novel study, we investigated the effects of low-dose Cd exposure (0, 0.03, 0.3, 3, and 30 mg·kg −1 ) in farmland soil within a typical constructed wetland environment. We assessed the activities of four soil enzymes (urease (URE), denitrification enzyme (DEA), dehydrogenase (DHA), and alkaline phosphatase (ALP)) at varying exposure durations (0 h, 24 h, and 48 h), evaluating hormetic characteristics across these time intervals. Additionally, we determined kinetic parameters, specifically the Michaelis constant ( K m ) and maximum reaction velocity ( V max ), for these enzymes while examining potential alterations in microbial community structure. Our findings revealed hormesis in all four soil enzymes at 24 h of exposure, with varying stimulus width and maximum hormesis rates. Interestingly, heavy metals did not significantly influence the diversity of soil microbial communities, but they did inhibit the ability of soil microbial communities to secrete extracellular enzymes. This resulted in a reduction in the soil enzyme pool and a consequential shift in overall soil enzyme activities. The conclusion of this study is that low-dose Cd primarily reduced extracellular enzyme secretion by soil microorganisms, leading to a reduction in the size of the soil enzyme pool and thereby inducing hormesis in soil enzyme activities.

Keywords: hormesis; cadmium; dose–response relationship; soil enzyme; bacterial community composition (search for similar items in EconPapers)
JEL-codes: Q1 Q10 Q11 Q12 Q13 Q14 Q15 Q16 Q17 Q18 (search for similar items in EconPapers)
Date: 2024
References: View references in EconPapers View complete reference list from CitEc
Citations:

Downloads: (external link)
https://www.mdpi.com/2077-0472/14/6/904/pdf (application/pdf)
https://www.mdpi.com/2077-0472/14/6/904/ (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:gam:jagris:v:14:y:2024:i:6:p:904-:d:1410743

Access Statistics for this article

Agriculture is currently edited by Ms. Leda Xuan

More articles in Agriculture from MDPI
Bibliographic data for series maintained by MDPI Indexing Manager ().