VULNERABILITE DE LA PRODUCTION DU MANIOC AUX CHANGEMENTS CLIMATIQUES ET PRIORITE D’ADAPTATION DANS LES AGGLOMERATIONS FRONTALIERES BENIN-TOGO (VALLEE DU MONO, AFRIQUE DE L’OUEST)

Abstract

In the south of the Mono Valley and in its Benin-Togo border towns, the production of cassava roots is hampered by fluctuating climatic conditions. It is in this context that this study is conducted, in order to analyze climatic variations and their impact on cassava production. Thus, climatological data (rainfall, temperature, relative humidity, potential evapotranspiration) and agricultural data (sown areas, yield and production of cassava) made it possible to characterize the major agroclimatic situations. Documentary research and field surveys formed the basis of the research methodology. In addition, data analysis reveals that the study area has a bimodal rainfall regime. The annual evolution of rainfall over the period 1988-2018 is marked by 45.16% of surplus years, 12.90% of normal years and 41.93% of deficit years. Therefore, the index of the deviation from the minimum value was calculated in order to see the years where the minimum need was not satisfied for certain years. In addition, an upward trend in average temperatures is noted with an average annual rate of 0.04°C/year. The linear correlations established between cassava yields and climatic parameters showed that there is no explicit linear relationship between cassava production and temperature and between cassava production and insolation. The rainfall and humidity dependence of cassava production are also low: 27% and 20% respectively. Thus, climatic parameters taken in isolation are not sufficient to explain agricultural yields. In addition, other factors could also play an inhibiting or enhancing role in yields. However, the producers have developed adaptation strategies in the face of climatic variability in the study area that deserve to be accompanied. KEYWORDS : Climate change, Cassava, Lower Mono Valley, border agglomeration, Benin and Togo