Zewide (2024) A coffee biochar-mineral NP interaction: Boon for soil health. The Scientific Temper. Doi: 10.58414/SCIENTIFICTEMPER.2024.15.2.09

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In southwestern Ethiopia’s Gawata district, low soil fertility is a significant challenge for potato farmers, leading to suboptimal yields. To address this issue, a field study was conducted in 2024, during both the Belg (February to May) and Meher (June to October) cropping seasons, to evaluate the effects of combining coffee biochar with nitrogen (N) and phosphorus (P) fertilizers on soil properties and potato yields.

The experiment tested twelve treatments, including various combinations of biochar (2.5, 5, 7.5 t/ha) and inorganic NP (25%, 50%, and 75% of the recommended dose), alongside control treatments with no fertilizer or 100% recommended NP dose. The goal was to find the optimal mix that improves soil health and boosts potato production.

Results showed that using 7.5 t/ha of biochar with 75% of the recommended NP dose significantly improved soil conditions. This treatment increased soil pH, organic carbon, total nitrogen, available phosphorus, cation exchange capacity, and exchangeable calcium and magnesium. It also decreased soil bulk density, exchangeable acidity, and aluminum levels. These changes in soil properties are crucial for better nutrient availability and overall soil fertility.

The study concludes that the combined use of 7.5 t/ha of biochar and 75% inorganic NP during the Belg season, or 25% of it during the Meher season, is an optimal strategy for enhancing soil health and potato productivity in the Gawata district. This integrated nutrient management approach can help mitigate the effects of low soil fertility and support sustainable agricultural practices in similar regions.