This study is entitled «Analysis of the rainfall aggressiveness on the soils of the N’Zi watershed. The objective is to analyze the importance of precipitation on soil erosion. To achieve the objective, daily, monthly and annual rainfall data on the N’zi watershed were collected over the period 1960 to 2019. The analysis of rainfall risks was possible for the index of erosivity of Arnoldus and Rango-Arnoldus rainfall, to graphical and spatial representations with R software and ArcGIS software. The results of the analysis of the interannual variability of precipitation show that the temporal aggressiveness generally declined during the 1970s. The rainfall aggressiveness indicates on a monthly scale a weak aggressiveness in general and the strongest would be seasonal at the level of the localities of the basin. It highlights three levels of rainfall aggressiveness on an annual scale: very aggressive aggressiveness (32%), less aggressive (48%) and more or less aggressive aggressiveness (20%), at the basin scale. Five (5) classes were distinguished; excess dominance (41%) qualified as high rainfall aggressiveness, dry period (30%) qualified as low rainfall aggressiveness, a minimum period (18%) qualified as very low rainfall aggressiveness, a maximum period (9%) qualified very high rainfall aggressiveness and a normal period (2%) qualified as average rainfall aggressiveness.

This study aims to assess the evolution of water balance parameters watershed Comoe in a context of climate change. Using the GR2M hydrological model, climate data from the climate model RegCM3 under the A2 emission scenario were simulated to get infiltration, runoff and evaporation and plant transpiration for the periods 1991-2000, 2031-2040 and 2091-2100. Similarly, monthly hydrological and climatic data were used to calibrate the parameters of GR2M hydrological model over the period 1961-1990. The calibration of the hydrological model gave Nash values between 57% to 72%. At validation, Nash criterion varies from 51% to 75%. The results of projection, revealed a decrease in runoff of 18.8% to 34% in 2031-2040 and 40% to 73% in 2091-2100 horizon in different localities. Refills of sheets that are through infiltration could decrease by 7% to 13% in 2031-2040 horizon and 49.3% to 70% in 2091-2100. The decrease in these two consecutive hydrological parameters is, firstly, to falling precipitation of 7.17% and, secondly, an increase in the evaporation and plant transpiration via the temperature increase of 3.6

This study aims to identify the optimal time of planting upland rice in the Center-west of C