Yam Production Risks Analysis for Food Security Under Climate Change in Gontougo Region (Côte D'ivoire), West Africa

Abstract

Yam, a staple food crop in Côte d'Ivoire, is the main source of livelihood for many inhabitants in the Gontougo region. Changes and variations in climate have significant impacts on its productivity. Soil depletion, variations in cropping seasons and dropping down of some agronomic practices due to climatic variability, varieties not adapted to the current climate and growing up of perennial crops such as cashews which dominating the landscape, are the main issues confronting the yam sector in the Gontougo region. This research aims to examine yam production risks and adaptive methods implemented by farmers using different methods. Firsly, we computed LULC changes and examined the vegetation healthy (NDVI) using Landsat 8 images and evaluate their effect on land surface temperature (LST). The Pearson correlation between the two parameters indicated that LST is hot when vegetation is low (strong negative coorelation) and the LULC classes forest and annual crops loose 48.13% and 65.14%, respectively of their areas for the benefit of perennial crops from 2015 to 2022. In the next step, a total of eight composite soil samples were collected ranging from 0 – 40 cm horizon on the yams farming in Tanda’s and Bondoukou’s department which are respectively forest and savannah zones and underwent physicochemical analysis. We discovered that soil under savannah is mainly coarse sandy (52.61%) as opposed to soil under forest which is less coarse sandy (41.63%). By computing some climate indices and surveyed communities, we discovered that yam farmers are mostly worried about rain uncertainties, decreasing of suitable land to grow and surface temperatures due to the decline of vegetation. The effects are felt most in Bondoukou’s department (92.48%) than in Tanda’s department (61%). Finally, the climate change scenarios coupled model intercomparison project phase 6 (CMIP6) historical and future model data including ssp2-4.5 and ssp5-8.5 have been used in the statistical Multiple Linear Regression model. The results of the simulations were carried out over 30 years (2025 - 2054) and indicate that both climate scenarios (ssp2-4.5; ssp5-8.5) show that yam yields will be lower than in the reference period. Yield variations could vary between -10% to -45% depending on the climate scenario. Effective and robust adaptation strategies, agricultural innovation, and substantial investment will be crucial to mitigate these negative impacts and sustain yam production in the face of rapid climate change.