By Onoja, Anthony Ojonimi
The study analyzed the effects of climate change on arable crops’ productivity, food security and adaptation strategies in Nigeria. It specifically ranked climate change risks affecting farmers in Nigerian agro-climatic zones; estimated the effects of climate factors on farm productivity (yield and net revenue variability); determined the effects of climate and socioeconomic variables on the level of household food security; ascertained the influence of farmers’ perception of climate change’s effects and household characteristics on choice of adaptation technologies adopted in coping with climate variability. It also evaluated the influence of gender on level of adoption of climate change adaptation technologies by the farmers. Five null hypotheses were tested. The study relied mainly on institutional and primary data for its analysis. Data were obtained using a set of structured questionnaire administered in a multi-stage, stratified random sampling manner on arable crop farmers (maize, rice, cassava, yam and cowpea farmers). Sixty (60) farmers each were randomly selected from 5 states in each of the five agro-climatic zones in Nigeria giving a total sample size of 300 farmers. Data collected were analyzed using Kendall’s W statistics, Ricardian model, OLS (three functional forms), Heckman’s Probit Selectivity Model, Gross Margin, Per Capita Household Food Consumption Expenditure and ANOVA. Soil nutrients loss (x̅ = 2.12), flood ( x̅ = 2.59) and increased temperature (x̅ = 2.50) were the most risky climate change factors in Swampy Forest, Tropical Forest, and Guinea Savannah zones respectively. In the Sudan and Sahel Savannahs, the most risky threat was drought (x̅ = 1.53 & 1.72 respectively). Five factors, namely, rainfall and temperature variations, planting materials costs, household size and labour cost exerted significant (0.05) effects on level of gross margins. Their elasticities were 1.20, 8.22, 0.11, 0.10 and 0.12, respectively. Rainfall, temperature, planting materials’ cost, gender, farmers’ age, years of formal education, household size and cost of labour significantly (0.05) influenced yield. Their elasticities were 2.61, 1457.25, 0.35, 2.71,-6.83, 130.03, 484.31 and 0.01, respectively. Rainfall, temperature, personal income and educational attainment significantly (0.05) determined food security with respective elasticities of 0.75, -10.96, 0.19 and -2.34. Food security index varied significantly (0.05) across agro-climatic zones. Extension contact, gender of the head of household, temperature and rainfall levels significantly (0.05) determined the decision to adapt to climate change. Their Z estimates were 5.75, 5.30, 2.32 and -9.50, respectively. Perception of climate change effect was significantly (0.05) influenced by education and agricultural extension access. Mean annual rainfall, temperature and location significantly (0.05) determined the level of adoption of climate change adaptation strategies by the farmers with elasticities of -0.70, -8.84 and -6.66, respectively. Gender exerted no significant effect on the level of adaptation to climate change. The rest four null hypotheses were rejected. Seven recommendations were made to address the issues found in the study. These included the need to resettle displaced farmers, promote investment on irrigation, provide weather stations to farmers and early warning information, capacity building of farmers, investing in research and gender mainstreaming in climate change policies.