The role of liming in improving soil health

Publication date: 10/10/2022
Extent: 40 pages

Contributions by: Richard C. Hayes, Jason R. Condon and Guangdi D. Li, New South Wales Department of Primary Industries, Australia

Chapter synopsis: Soil acidity is a threat to a healthy soil with far-reaching consequences, both direct and indirect, on soil chemical and physical properties, impacting the growth, health and composition of organisms growing in a soil and with potential for negative off-site impacts. All agricultural production systems are acidifying meaning that the amelioration of acidity is essential in maintaining and improving the health of agricultural soils. The application of finely-ground limestone (CaCO3) remains the most efficient means of ameliorating low soil pH due to its high neutralizing value. However, the sparingly soluble nature of lime increases the time it takes to react with the soil volume. The mixing of lime through cultivation goes some way to overcoming this barrier but is only effective to the depth of incorporation in the short term. Lime movement below the depth of incorporation is very slow. As a consequence, acidic subsurface soils are common and lime can have limited effect on the amelioration of subsurface acidity in the short term. Liming, therefore, needs to be a pro-active, long-term strategy, aiming to avoid degradation of the soil resource by minimizing the inevitable acidification of subsurface depths.

DOI: 10.19103/AS.2021.0094.19