Maize is an important staple in Africa, which necessitates immediate drying to preserve the postharvest quality. The traditional drying of maize in the open sun is prone to adverse weather and extraneous contamination. In this study, the drying performance of an inflatable solar dryer (ISD) was compared to direct sun drying (DSD) in Gombe Town, Wakiso District (Uganda) by analysing the moisture content, yeasts, moulds, aflatoxin, and colour. The maximum temperature inside the ISD reached 63.7 °C and averaged 7 °C higher than the ambient temperature. Maize was dried using both methods to a moisture content below 14% after two days. In one of the received maize lots that was already heavily contaminated after harvest, drying with DSD and ISD reduced the aflatoxin content from 569.6 µg kg⁻¹ to 345.5 µg kg⁻¹ and 299.2 µg kg⁻¹, respectively. Although the drying performance in terms of drying time and product quality regarding colour, yeast, and mould was similar for both drying methods, the advantage of ISD in reducing the risk of spoilage due to sudden rain is obvious. A strategy for the early detection of aflatoxins in maize is recommended to avoid contaminated maize in the food chain.

This study assessed the relative influence of agroecological zones (AEZs) and altitude on soil nutrient dynamics to guide site‑specific management. Soil samples from 20 marshlands across seven AEZs, spanning 944 to 1900 m a.s.l., were collected from 0 – 30 cm and analysed for pH, exchangeable bases (Ca, Mg, K, and Na), organic carbon (OC), total nitrogen (TN), available phosphorus (P), and texture using ANOVA, Welch’s tests, and PCA. Fertility varied markedly among AEZs: the Imbo zone exhibited near‑neutral pH and higher base cations, while Mayaga and the Congo Nile Watershed Divide were acidic and nutrient‑poor. Low‑elevation sites (944 – 1044 m a.s.l.) had higher pH (6.32) and base cations, whereas high‑altitude soils (>1800 m a.s.l.) were acidic (pH 4.92) and depleted. Effect size analysis confirmed altitude’s stronger explanatory power for Ca ( η² = 0.53 vs. η² = 0.49), Mg ( η² = 0.54 vs. η² = 0.37), K ( η² = 0.47 vs. η² = 0.29) and pH ( η² = 0.45 vs. η² = 0.33), while AEZs better explained TN ( η² = 0.27 vs. η² = 0.09), though altitude produced a notable mid‑elevation TN peak (1345 – 1544 m a.s.l.), and OC ( η² = 0.31 vs. η² = 0.10). Integrating altitude with AEZ‑based frameworks and applying organic amendments in high‑altitude acidic zones can improve nutrient use efficiency, rice yield, and sustainable marshland productivity in Rwanda.