Use of a zeolite synthesised from alkali treated kaolin as a K fertiliser: glasshouse experiments on leaching and uptake of K by wheat plants in sandy soil.
The research paper presents research conducted by Naoko Zwingmann, Ian D.R. Mackinnon, and Robert J. Gilkes on the effectiveness of a synthetic zeolite, referred to as K-zeolite N, derived from alkali-treated kaolin, as a potassium (K) fertilizer for wheat plants grown in sandy soil. The study aimed to evaluate the bioavailability of K from this zeolite compared to a conventional soluble K fertilizer (KCl) through glasshouse experiments.
The researchers conducted experiments in both highly-leached and non-leached conditions over four weeks. They found that K-zeolite N exhibited a high cation exchange capacity (CEC) of approximately 500 meq/100g, which significantly reduced the leaching of ammonium (NH4+) fertilizers. In non-leached pots, wheat plants fertilized with K-zeolite N were slightly larger than those fertilized with KCl, and the elemental composition of the plants was similar, except for a significantly higher concentration of silicon (Si) in the K-zeolite N group. This higher Si concentration is suggested to enhance the plants' resistance to fungal diseases.
In highly-leached pots, both K sources experienced rapid leaching, with over 85% of K from KCl and 75% from K-zeolite N lost within three days. The plants in these pots were severely K deficient, resulting in significantly smaller growth compared to non-leached pots. The study concluded that while K-zeolite N is effective as a K fertilizer under non-leaching conditions, its performance diminishes in highly leached sandy soils.
This research paper is significant in the field of agricultural science, particularly in the study of soil amendments and fertilizers. It contributes to ongoing discussions about sustainable agricultural practices by exploring alternative fertilizers that can reduce nutrient leaching, which is a major environmental concern. The findings suggest that K-zeolite N could be a viable option for improving K availability in sandy soils, which are often nutrient-poor and prone to leaching. The research highlights the importance of considering both the agronomic effectiveness and environmental impact of fertilizers, offering insights that could benefit farmers, agronomists, and environmental scientists.
