Abstract:
Establishing food security in sub-Saharan African countries requires a comprehensive
and high resolution understanding of the driving factors of crop production. Poor soil and adverse
climate conditions are among the major drivers of poor regional crop production. Drought and
rainfall variability challenges are not fully being addressed by rainfed producers in semiarid areas.
In this study, we analysed the spatiotemporal rainfall variability (STRV) and its effects on pearl millet
yield using two seasons of data collected from 38 rain gauge stations scattered randomly in farm
plots within a 1500 ha area of semiarid central Tanzania. The STRV effects on pearl millet yield under
flat and tied ridge management were analysed. Our results show that seasonal rainfall can vary
significantly for neighboring fields at distances of less than 200 m, which impacts yield. The STRV for
daily rainfall was found to be more critical than for total seasonal rainfall amounts. Scattering fields
can help farmers avoid total harvest loss by obtaining at least some yield from the areas that received
adequate rain. The use of tied ridges is recommended to conserve soil moisture and improve yields
more than flat cultivation in semiarid areas.
