Effect of Climate Change on Food Crop Production in Southeast, Nigeria: A Co-Integration Model Approach (Published)
This paper studied the effect of climate change on selected food crop production in Southeast, Nigeria. The data were sourced from National Root Crops Research Institute, Umudike, National Bureau of Statistics and the Central Bank of Nigeria (CBN) bulletin. Data on crop yield and climate variables from 1984 to 2014 were collected. Descriptive Statistics, Co-integration analysis and Error Correction Model were adopted. The finding reveals unsteady climatic pattern with peak points across the period under review. The Augmented Dickey-Fuller test for unit root reveals that yam; maize and cassava outputs were non stationary but became stationary after the differencing. All climate variables showed stationary at first level. Result shows the existence of one co-integrating vector in the three models. The results shows that the coefficients of ECM(-1) which indicates speed of adjustment of the crop outputs to the equilibrium when a disturbance has occurred are -0.365 (p<0.01), -0.211 (p<0.05) and -0.599 (p<0.001) for yam, maize and cassava output models respectively. The coefficients of multiple determination (R2) for yam, maize and cassava were 0.611, 0.440 and 0.2669 respectively. In yam model, the coefficients show that all variables except lagged yam output and temperature have positive relationship with the yam output; the coefficients of lagged maize output, rain days and temperature are negative while rainfall volume, humidity and sunshine are positive in maize model and in cassava model, coefficients of rainfall volume, rain days, sunshine and lagged cassava output are positive while temperature and humidity are negative. Results show that climate change impacted yam and maize output. It is recommended that adequate mitigation and adaptive measures be put in place to reduce the effect of climate change in order to achieve an appreciable agricultural productivity.