Linkages Between Exchangeable Cations, Maize Growth and Yield After Prescribed Fire and Amendment Interaction in a Tropical Environment
摘要
Exchangeable cations are depleted by prescribed fire and are directly linked to maize growth and yield. However, the incorporation of amendments can improve cations and enhance maize growth and yield after fire. Therefore, the study aimed to investigate the interaction of different fire intensities and mulch with different amendment types and how exchangeable cations, maize growth parameters, and yield responded to these interactions. The study employs a factorial design arranged in a randomized complete block design of 12 treatment combinations of three amendment types and four land preparation and management methods (200 °C, 500 °C, mulch, and no-fire) replicated three times to give 36 experimental plots. The Ca2+ content reduced while the Mg2+, K+, and Na+ content increased in fire plots compared to no-fire and mulched plots one day post-fire, before amendments incorporation. Plant height was higher with and without amendments in fire plots by 17.3% and 12.7% than in the no-fire plot, respectively, while in the mulched plot, it was higher with and without amendments by 14.7% and 12.7% than in the no-fire plot, respectively. After harvesting, the Mg2+ content increased in the mulched treatment with amendment by 32% than without amendment. Grain yield reduced without amendment in the no-fire plot by 21.3%, 21.6% and 5.8% compared to 200 °C, 500 °C, and mulched treatments, respectively. With sole urea incorporation, grain yield was lower in the no-fire plot by 5.5%, 16.4% and 18.4% compared to 200 °C, 500 °C, and mulched treatments, respectively. This study highlights the importance of incorporating amendments to fire and mulched-treated soils, as it increases the availability of soil nutrients, especially magnesium. This results in sustainable maize growth and yield. However, considering the negative environmental effect of fire (as regards global warming), the study encourages farmers to adopt mulching with and without amendments incorporation as a viable land management practice for maize cultivation.