THE EFFECTS OF CLIMATE VARIABILITY ON MAJOR CASH CROP YIELD IN NIGERIA

Abstract

This study aims at investigating the effect of climatic variables on some major cash crop yield in Nigeria; It made use of climate data (rainfall, relative humidity, maximum and minimum temperature) and crop (cocoa, groundnut, cotton, rubber, and palm produce) yield data for individual zone for a period of 10 years (1995 to 2004). Climate and crop yield were collected from the Nigeria Meteorological Agency and Bureau of Statistics, Lagos respectively. The climate data was grouped into four according to seasons i.e Dry season (DJF), Pre-WET Season (MAM), Wet Season (JJA) and Pre-Dry Season (SON). Descriptive and inferential statistics were used to investigate the characteristics of each dataset. Correlation and regression analyses were both employed to analyze the data so as to establish a relationship between seasonal climatic variables and crop yield. Results show that DJF’s maximum temperature and MAM’s minimum temperature, JJA’s maximum temperature had significant effect on cocoa yield (Multiple Regression and correlation coefficient (r2 of 0.71); DJF minimum temperature and rainfall, MAM’s maximum temperature and relative humidity, and JJA’s rainfall, maximum temperature and relative humidity had significant effect on cotton yield (multiple Regression of 0.97 and correlation coefficient (r2) of 0.96) DJF rainfall, JJA’s rainfall and minimum temperature and SON’s rainfall, maximum temperature and correlation coefficient (r2) of 0.92); DJF’s minimum temperature, JJA Rainfall and maximum temperature and SON Rainfall, maximum temperature and minimum temperature had significant effects on Groundnut yield (Multiple Regression of 0.87 and correlation coefficient (r2) of 0.76); MAM rainfall, JJA relative Humidity and SON minimum temperature are the most significant effect on cotton yield (multiple Regression of 0.88 and correlation coefficient (r2) of 0.79). There is a need to ensure that planning integrate risks of climate change and variability, and thereby reduce who vulnerability. Climate information itself needs to be delivered and disseminated in ways that increase its practical value to the farmers. For this to be achieved co-ordination across all sectors is required.