Cover Cropping and Fallow Management for Soil Fertility Enhancement in the Nigerian Middle Belt

This study examines cover cropping and fallow management systems for soil fertility enhancement in the Nigerian Middle Belt, covering North Central states including Benue, Kogi, and Niger. Cover crops and managed fallows are traditional soil management strategies that are increasingly recognised within conservation agriculture frameworks as sustainable alternatives to mineral fertiliser dependency. Understanding which cover crop species and fallow management approaches are most effective under Middle Belt conditions is important for designing extension recommendations. This study uses a long-term comparative field experiment across three research sites in the three states, testing six systems: bare fallow, natural vegetation fallow, Mucuna pruriens cover crop, Tephrosia vogeli cover crop, Stylosanthes guianensis pasture-cover crop, and Canavalia ensiformis, each managed for two seasons before planting a test maize crop. Soil nitrogen, phosphorus, organic carbon, microbial biomass, and subsequent maize yield are measured. Economic analysis compares system costs and returns. Findings reveal that Mucuna pruriens produces the highest nitrogen addition of 186 kilograms per hectare and the strongest subsequent maize yield benefit at 4.8 tonnes per hectare. Tephrosia provides significant weed suppression benefits in addition to nitrogen contributions. Natural vegetation fallow produces intermediate soil fertility benefits. The study concludes that legume cover crops outperform unmanaged fallows for soil fertility improvement in the Middle Belt. It recommends Mucuna pruriens as the priority cover crop species for extension promotion.

Keywords: cover cropping, soil fertility, Middle Belt, Mucuna pruriens, fallow management.