Abstract
Liming has widespread and significant impacts on soil processes and crop responses. The aim of this study was to describe the relationships between exchangeable cation concentrations in soil and the relative yield of spring barley. The hypothesis was that yield is restricted by the concentration of a single exchangeable cation in the soil. For simplicity, we focused on spring barley which was grown in nine years of a long-term experiment at two sites (Rothamsted and Woburn). Four liming rates were applied and in each year the relative yield (RY) and the concentrations of exchangeable cations were assessed. Liming had highly significant effects on the concentrations of most exchangeable cations, except for Cu and K. There were significant negative relationships (either linear or exponential) between the exchangeable concentrations of Mn, Cd, Cr, Al, Fe, Cu, Co, Zn and Ni in soil and soil pH. The relationships between RY and the concentrations of selected exchangeable cations (Mn, Ca and Al) were described well using log-logistic relationships. For these cations a significant site effect was probably due to fundamental differences in soil properties. At both sites the concentrations of exchangeable soil Al were excessive (> 7.5 mg kg−1) and were most likely responsible for reduced barley yields (where RY ≤ 0.5) with soil acidification. At Rothamsted barley yield was non-limited (where RY ≥ 1) at soil exchangeable Mn concentrations (up to 417 mg kg−1) greater than previously considered toxic, which requires further evaluation of critical Mn concentrations.
Highlights
Acidic soils are a challenge to agriculture and acidification has been identified as one of the most significant degrading processes of soils at the global scale (FAO 2015)
Liming and site effects on soil pH and the concentrations of exchangeable cations in the soil. Treatment effects and their interaction were tested on measurements of soil pH and the concentrations of exchangeable cations in the soil for 1967 at each site (Rothamsted and Woburn) (Table 2)
Site differences in exchangeable cation concentrations are influenced by the exact composition of cations, which influences whether divalent cations such as Mg2? or Ca2? are displaced by trivalent cations such as Al3? or Fe3? (White 2013)
Summary
Acidic soils are a challenge to agriculture and acidification has been identified as one of the most significant degrading processes of soils at the global scale (FAO 2015). Identifying constraints to crop (Holland et al 2019) and grassland (Stevens and Laughlin 1996) production on acid soils is an important target for current research (Holland et al 2018). Acidic soils (\ pH 4.5) have elevated concentrations of those exchangeable cations (e.g. Al, Mn), which can restrict plant growth. Much research has been focused upon the effects of acidity on plant growth, and root growth in particular. Liming is a common management strategy to ameliorate acidic soils that has multiple long-term effects on soils, crops and biodiversity (Holland et al 2018). Liming can reduce the uptake of potentially harmful cations such as Cd or Zn by crops in contaminated soils (Hooda and Alloway 1996)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
