Analysis of the Efficiency of Precipitation on the Evolution of Agricultural Production in Upper-Casamance (South Senegal) between 1985 and 2018

Abstract

In Senegal, rainfall is the main factor affecting agricultural production. In Upper-Casamance, it is a major equator for the development of agriculture, makes farmers vulnerable, and leads to changes in farming systems. The objective of this study is to analyze the evolution of agricultural production over the last 34 years in Upper-Casamance and the impact of rainfall variability on yields. To this end, data on cereal production (millet, sorghum, corn, rice and fonio) and industrial production (groundnut, cotton and cassava) in tons between 1985-1986 and 2018-2019 from the Regional Directorate of Rural Development (RDRD) of Kolda and precipitation data over the same period acquired at ANACIM was used. Production data are processed on the basis of statistical tests, including descriptive statistics, Pearson correlation, and simple linear regression. The calculation of rainfall data is based on the calculation of the annual average rainfall, the Standardized Precipitation Index (SPI), the number of rainy days per year, the average precipitation per day of rain, and the start and end date of the "agronomic" monsoon, and its duration. Analysis of the results showed an increase in agricultural production as rainfall conditions are good. The simple linear regression calculation for each product at the p<0.05 threshold indicated that rice, corn, groundnuts and cassava are the crops that depend significantly on the annual rainfall period. Analysis of the start and end dates showed that the length of the agronomic season (on average 112 days) appears to be favorable for the production of millet and groundnut.

Keywords

• Agricultural production
• Rainfall variability
• Agronomic monsoon,

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