Evaluation of Different Crop Covers as Improved Short-Term Fallow in the Improvement of Soil Fertility and Weed Control in the Southeastern Nigeria

Decades of cropping without fallow have decreased soil fertility, reduced levels of soil organic matter, an invasion of noxious weeds and acidified soils. Weeds have invaded the land, forcing small-scale farmers to abandon their plots. Thus, achieving food security for a rapidly growing population will require intensification of food production on existing cropland through improving soil fertility and agronomic practices. In an attempt to improve on soil conservation and land management that are economically viable, ecologically sound, and socially acceptable, the study tend to evaluate different plant species in the rehabilitation of an ultisol of Ishiagu that has been under cultivation. Four treatments; (Mucuna, Cowpea and Maize), including the control were built into a randomized complete block design (RCBD) with three replications. Soil chemical properties tested were soil pH, organic carbon, total nitrogen exchangeable K+, Mg2+, Na+ and Ca2+. Others were CEC; percent base saturation, exchangeable acidity and available phosphorus, while the weed weight was also measured. The results showed that soil pH, organic carbon and total nitrogen were significantly improved by legume covers better than maize cover and control. It was obtained that plots planted with legumes significantly (P < 0.05) increased the exchangeable Mg2+, Ca2+, BS, CEC and available P relative to the maize and control plots. In addition, there was a significant higher reduction in weed suppression by the legume crop covers than maize cover and the control.