Assessment of the Effect of Climatic Variables on Vegetation in North Central, Nigeria

Abstract

This study assessed the effects of temperature and precipitation on vegetation dynamics in North-Central Nigeria from 2000 to 2020. The study integrated Landsat-derived Normalised Difference Vegetation Index (NDVI), MODIS Land Surface Temperature (LST), and CHIRPS precipitation datasets. Google Earth Engine was used for image preprocessing and annual compositing, while ArcGIS 10.8 was employed for spatial harmonisation, projection standardisation, and raster-to-point conversion. Ordinary Least Squares (OLS) regression, Pearson correlation, partial correlation, Multiple Linear Regression (MLR), and residual analysis were applied to quantify climate–vegetation relationships and distinguish climate-driven change from anthropogenic influence. Mean NDVI exhibited a marginal positive trend (β = 0.0018 yr⁻¹), suggesting regional vegetation stability. However, spatial disaggregation revealed that 42.7% of the area experienced greening while 18.8% showed degradation, particularly around urbanising centres, mining corridors, and intensively cultivated landscapes. Temperature increased persistently at +0.0976 °C yr⁻¹, while rainfall showed a weak declining tendency (−0.1474 mm yr⁻¹) with strong interannual variability. Correlation analysis revealed a stronger negative NDVI–temperature relationship (r = −0.4925) than NDVI–precipitation (r = 0.2699). Residual analysis identified negative clusters around Abuja, Jos, and Lokoja, indicating anthropogenic pressure beyond climatic expectations. Vegetation dynamics in North-Central Nigeria are governed by the combined effects of rising temperature, rainfall variability, and human disturbance. Thermal intensification constitutes the dominant climatic constraint. The study recommends climate-responsive land-use planning, afforestation, soil–water conservation, and routine geospatial monitoring to enhance ecosystem resilience in the Guinea Savannah transition belt.