Climate Change Impact and Variability on Cereal Productivity among Smallholder Farmers under Future Production Systems in West Africa

Dilys S Maccarthy,Mouhamed Ly,Pierre S Traore,Peter A Y Ampim,Bright S Freduah,Benedicta Yayra Fosu-Mensah,Myriam Adam,Samuel G K Adiku

doi:10.3390/su13095191

Abstract

Agriculture in West Africa is constrained by several yield-limiting factors, such as poor soil fertility, erratic rainfall distributions and low input systems. Projected changes in climate, thus, pose a threat since crop production is mainly rain-fed. The impact of climate change and its variation on the productivity of cereals in smallholder settings under future production systems in Navrongo, Ghana and Nioro du Rip, Senegal was assessed in this study. Data on management practices obtained from household surveys and projected agricultural development pathways (through stakeholder engagements), soil data, weather data (historical: 1980–2009 and five General Circulation Models; mid-century time slice 2040–2069 for two Representative Concentration Pathways; 4.5 and 8.5) were used for the impact assessment, employing a crop simulation model. Ensemble maize yield changes under the sustainable agricultural development pathway (SDP) were −13 and −16%, while under the unsustainable development pathway (USDP), yield changes were −19 and −20% in Navrongo and Nioro du Rip, respectively. The impact on sorghum and millet were lower than that on maize. Variations in climate change impact among smallholders were high with relative standard deviations (RSD) of between 14% and 60% across the cereals with variability being higher under the USDP, except for millet. Agricultural production systems with higher intensification but with less emphasis on soil conservation (USDP) will be more negatively impacted by climate change compared to relatively sustainable ones (SDP).

Highlights

IntroductionThe increasing population of West Africa, which is projected to become three-fold by 2050 over the baseline value in 2010 [1] has implications for food security in the sub Sustainability 2021, 13, 5191
This study provides a quantification of the climate change impact on yields of cereals in two semi-arid communities in Ghana (Navrongo) and Senegal (Nioro du Rip), as well as the diversity in the magnitude of climate change among smallholder farmers under two future production systems scenarios
The nature of future production systems will influence the magnitude of the climate change impact among smallholder farmers in West Africa

Summary

Introduction

The increasing population of West Africa, which is projected to become three-fold by 2050 over the baseline value in 2010 [1] has implications for food security in the sub Sustainability 2021, 13, 5191. Sultan et al [6] reported significant projected increases in temperature across the entire West African sub region by 2050, which could alter the climatological hydrology and crop physiological behaviour. Increased temperatures could accelerate crop development, shorten life cycles and increase crop respiration. These effects would result in a reduction in crop yields. The projected changes in these weather variables would pose challenges to the livelihoods of farmers

Objectives

Methods

Results

Discussion

Conclusion