MULTIVARIATE EFFECTS OF CLIMATE VARIABILITY ON MAIZE YIELD AND IMPLICATIONS FOR FOOD SECURITY IN EJULE, KOGI STATE, NIGERIA

This study investigates the multivariate effects of climate variability on maize (Zea mays L.) yield and their implications for food security in Ejule, Ofu Local Government Area, Kogi State, Nigeria, over a thirty-one-year period (1992–2023). Climatic data including rainfall, temperature, soil temperature, solar radiation, relative humidity, and wind speed were obtained from the Nigerian Meteorological Agency (NIMET), Lokoja station, while maize yield data were sourced from the Kogi State Agricultural Development Project (KADP) and cross-validated with the Federal Ministry of Agriculture and Rural Development (FMARD). Descriptive statistics, trend analysis, and multivariate regression were applied to examine long-term climatic trends, yield responses, and their interactions. Results revealed strong inter-annual rainfall variability without a clear long-term trend, alongside a significant warming trend in temperature (+0.3–0.4°C per decade) mirrored by rising soil temperatures. Maize yields exhibited three distinct phases: stagnation in the 1990s and early 2000s (≈1.3–1.5 t ha⁻¹), moderate growth in the 2010s (≈1.8–2.0 t ha⁻¹), and stabilization after 2019 around 2.13–2.17 t ha⁻¹ following a peak of 2.49 t ha⁻¹ in 2019. The regression model was highly robust (R² = 0.959, F = 24.1, p < 0.001), with rainfall exerting a modest positive effect (β = +0.192, p < 0.05), while temperature (β = –0.355, p < 0.01) and soil temperature (β = –0.312, p < 0.05) had significant negative effects. Solar radiation, relative humidity, and wind speed were not statistically significant predictors. The study concludes that maize production in Ejule is more constrained by thermal stress than by rainfall deficits alone, highlighting a growing risk of climate-induced yield stagnation. To safeguard food security, adaptation measures must include the adoption of heat- and drought-tolerant maize varieties, soil moisture conservation practices, small-scale irrigation, and strengthened climate information services. Policy interventions such as input subsidies, credit facilities, and enhanced extension services are also essential to build the resilience of smallholder farmers in the Guinea Savanna zone.