Assessing Rainwater Adequacy for Crop Cultivation under Varying Rainfall Probabilities in the Blue Nile Region, Sudan

الملخص

The amount of rainfall and the period between rainfall events play a fundamental role in watering rainfed crops, thereby improving productivity. rainfed agriculture in Blue Nile region is one of the important areas in the Sudan. This study evaluated the adequacy of seasonal rainfall compared to crop water requirements for major rainfed crops grown in the Blue Nile region under five climatic conditions: wet, semi-wet, normal, semi-dry, and dry seasons. Daily climate data were obtained from Sudan Metrological Authority (SMA) records during the period from 1971 to 2021. Start, end and length of the growing season were determined for the five season types. Rainwater before, during and after the growing season was calculated. Seven summer crops were studied, namely: sorghum, millet, sesame, sunflower, groundnuts, soya bean and cotton. Crop life cycle, length of growth stages and crop coefficients were used to calculate ETc. The results indicated that while early-season rainfall often meets crop demands, mid and late-season deficits are common, particularly in semi-dry and dry seasons. Though total rainfall was adequate, its uneven distribution underscores the necessity for using suitable crop management and soil moisture conservation practices. The study concluded that all studied crops are viable under current rainfall regimes in Blue Nile region, however, suitable crop management and soil moisture conservation practices have to be considered during mid and late season.