La variabilité pluviométrique et ses incidences sur les rendements agricoles dans la région des Terres Neuves du Sénégal oriental

Abstract

The New Lands, like the region of Tambacounda (eastern Senegal), are rich in agricultural potential. The cultivation of cereals such as millet, sorghum, maize and peanuts occupies a prominent place in food security and improves farmers’ incomes. The spatio-temporal variability of rainfall, initiated since the 1970s, has had considerable impacts on agricultural activities. Indeed, the disruption of the rainy season (heavy rains or showers, recurrence of rainfall, late start and early end of wintering) is not without effects on crop productivity.This present study seeks to show the rainfall variability in the New Earth and its influence on agricultural production. The methodology adopted is based primarily on a statistical approach with the use of the Pettitt test (1979), the Standardized Rainfall Index (SPI) (McKee et al., 1993), the deviation from the mean of the series and the cartography of the spatial evolution of the isohyets. These methods allowed us to understand the evolution of rainfall in the New Earth and to determine the years with excess rainfall and those with deficit. Through the Pettitt test (1979), we observed a break in the Tambacounda station (1969) and the absence of a rupture in Koumpentoum. This deterioration has, however, impacts on the agriculture of the area. Indeed, the analysis of the results on yields also shows that during certain years, the variation of the rains affects the agricultural production.

Keywords

• rainfall variability
• impacts
• agricultural yields
• New Land
• Eastern Senegal