Findings from this study indicate that tree cover, daily rainfall intensity, and the interaction between the two strongly influenced soil water dynamics in an agroforestry parkland in semiarid West Africa.

Tropical regions are likely to experience more intense rainfall events in the future. Such an increase in rainfall intensities will affect soil and groundwater recharge, with potential consequences for millions of people. However, little is known about the impact of tree cover on soil and groundwater recharge under higher rainfall intensities. Here, wthe authors investigated the effect of tree cover and rainfall intensity on soil water drainage in an agroforestry parkland in West Africa.

The isotopic signature of soil water drainage suggested less evaporation and a higher degree of preferential flow in small compared with large open areas. The results suggest that maintaining or promoting an appropriate tree cover in tropical African drylands may be key to improving deep soil and groundwater recharge under a future climate with more heavy rainfall.