Almost half of the world’s potentially arable land area occurs on acidic soils. In Australia, 77–90 million hectares of agricultural land are affected by soil acidity, and these areas are expanding due to ongoing acidification.
This acidity affects agricultural productivity. Amelioration of soil acidity is expected to increase crop residue inputs (stems, roots and other plant matter left in the soil after harvests), but this may also accelerate organic matter decomposition.
In the 29th Annual GW Leeper Memorial Lecture, Professor Caixian Tang will report on his team’s research on the impacts of soil acidity (pH) on soil organic matter dynamics.
In the lecture, Professor Tang will provide an overview on the short and long-term impacts of lime application on the dynamics of soil organic carbon in acid soils, followed by a summary of the effects of crop residues on soil pH and associated mechanisms. Finally, he will discuss how plant roots affect the decomposition of soil organic matter through the rhizosphere priming effect and by changing pH in the rhizosphere, the dynamic soil microbiome immediately adjacent to plant roots.
The Leeper Lecture is hosted by Soil Science Australia (Victoria Branch) and the Faculty of Veterinary and Agricultural Sciences as part of the Dean's Lecture Series.