Abstract

The study assessed household vulnerability to climate change and its effect on yam and cassava production in Oyo state, Nigeria. Primary and secondary data were used for the study. Data on yam and cassava yield between 1990 and 2009 were obtained from the Oyo State Agricultural Development Programme (ADP) while data on climate variables between 1976 and 2010 were obtained from the Nigeria Institute of Meteorology, Oshodi. Primary data on the components of vulnerability that is adaptive capacity, sensitivity and exposure were also obtained from cassava and yam farmers using structured questionnaire to assess their vulnerability to climate change. Multistage sampling technique was employed to select 120 respondents across the three agro-ecological zones of the study area. This was done by purposively selecting five farm villages in each of the three agro-ecological zones in the study area and randomly selecting eight farmers from each of the villages. Trend, regression and principal component analytical tools were used to analyze data collected. The integrated vulnerability assessment approach was adopted using the vulnerability indicator. The result showed that the mean annual temperature and mean annual sunshine hour have been increasing by an average of 0.012oC (p<0.01) and 0.004 hours (p<0.01) per year respectively. This confirms the occurrence of global warming in the study area. The study revealed that sunshine hour significantly (p<0.05) affected yam yield. Household’s vulnerability to climate change in the three agro ecological zones as measured by the vulnerability index (VI) was found to be highest in the derived savannah (VI=-0.99) followed by the savannah (VI=0.46) and lowest in the rain forest (VI=0.53). The derived savannah zone recorded the highest vulnerability with a relatively low proportion of the population having access to quality home (2.5%), insecticide (30%), fertilizer (30%), improved seedlings (30%), road (15%), health services (15%), primary and secondary schools (15%), veterinary services (0.03%), food market (42.5%), and microfinance institutions (0.03%). The study recommended among others that crop-breeding researchers should work towards developing improved varieties of cassava and yam that can cope with future expected change in climate. Also, integrated rural development schemes aimed at increasing access to basic social amenities should be established by the government with the cooperation of the residents as this will improve adaptive capacity and thereby reduce vulnerability of farmers to climate change  in the study area.

Key words: Climate change, Vulnerability, Food, Crop production, Oyo State