Impact of Climate Change on Agropasture in Mali and Adaptation Strategies

Abstract

In Mali, like other developing countries, agropastoralists are particularly vulnerable to the effects of climate change. This study was conducted to examine the impacts of climate change on crop yields (sorghum and groundnut) and to assess the adaptability of agropastoralists to the impacts of climate change. To this end, an analysis of daily rainfall and temperature data covering 60years (1960 to 2020) from the Ségou, Sikasso and Bamako stations was carried out using Instat+ v3.36, Rstudio, XLSTAT and Rclimdex software. Four climate models were used for the climate projection, (GFDL-ESM4, INM-CM4-8, INM-CM5-0 and NorESM2-MM) of phase 6 of the coupled model intercomparison project (CMIP6) under scenarios SSP2-4.5 and SSP5-8.5 of the annual rainfall, solar radiation and temperature for a period of 2021-2050 and 2070-2100 in the region of Ségou, Niono, Sikasso, Kolondieba and Bamako. MAKESENS was used for the realization of a linear model to estimate the magnitude of the trend in the time series. Field survey were conducted among 355 agropastoralists in three regions of Mali to assess the impacts and adaptation strategies of agropastoralists. The analysis of climate data shows a downward trend for rainfall. As for temperature, there was an upward trend in the series from 1960 to 202 at the station of Ségou, Sikasso and Bamako. Intercomparison of coupled models (CMIP6) under scenarios SSP2-4.5 and SSP5-8.5 of annual rainfall, solar radiation and temperature in the near future period 2021-2050 and far future 2070-2100 in the region of Ségou, Niono, Sikasso, Kolondieba and Bamako was conducted. According to the scenario SSP2-4.5 in the near future period 2021-2050 an upward trend in average annual temperatures of 0.14°C for five localities of Mali (Ségou-Niono, Sikasso-Kolondieba and Bamako) compared to the scenario SSP5-8.5 with an upward trend of 0.43°C. Scenario SSP5-8.5 in the far future period, 2070-2100 revealed an upward trend in annual average temperatures of 0.27°C. On the other hand, for the scenario SSP5-8.5 the upward trend is 0.58°C. Experimental tests were carried out on sorghum and groundnut crops during the 2021 agricultural campaign. Six varieties of sorghum CSM63E, CSM388, DT-15, KIT19, Tiandougou-Coura and Soubatimi and two varieties of groundnut (ALLASSON Fleur 11 and ICVG 26024) were studied. The DSSAT Model was used to calibrate and simulate crops yields and also determine crop growth of the six sorghum varieties studied. The calibration has been carried out to determine the genetic coefficients of these four based on the results obtained from the experiments. The climate projection of crop yields from 2015-2099 in the different regions of Mali for a spatial model was evaluated. It indicates a low tops weight simulated yield with an average of 9761kg/ha and 17% coefficient of variation for five varieties (CSM388, DT15, KIT19, Soubatimi and Tiandougou-coura). As for CSM63E gave a better tops weight of 10141kg/ha with 17.20% coefficient of variation. As for grain yield shows a higher yield of 3449 kg/ha for fives varieties (CSM388, DT15, KIT19, Soubatimi and Tiandougou-coura) with 18% coefficient of variation unlike CSM63E which has the lowest yield 1694kg/ha with 10%.