Short-Term Effects of Tillage Systems, Fertilization, and Cropping Patterns on Soil Chemical Properties and Maize Yields in a Loamy Sand Soil in Southern Mozambique

Sub-Saharan Africa (SSA) agriculture is characterized by dependence on erratic rainfall, inadequate conservation practices, and a decline in soil fertility resulting in low crop productivity. Therefore, conservation agriculture (CA) has been proposed as an alternative to improve soil fertility and productivity. Hence the aim was to investigate the effects of tillage systems, fertilization, and cropping patterns on selected soil chemical properties (pH, organic carbon, total nitrogen, extractable phosphorus, exchangeable cations, and cation exchange capacity) and identify which cropping pattern maximizes stover and grain maize–legume productivity and land use. A two-year (2016/17–2017/18) field experiment in a loamy sand soil was conducted at Nhacoongo Research Station, southern Mozambique. Two tillage systems (conservation (CA) and conventional tillage (CT)), two fertilization treatments (fertilized and unfertilized), and seven cropping patterns (four sole crops and three maize–legume intercrops) were evaluated in a randomized complete block design with split–split plot arrangement and replicated four times. CA practices resulted in significantly higher soil chemical properties and increased stover and grain yields as compared to CT practices, but fertilization demonstrated insignificant effects on soil chemical properties and significant influences on stover and grain yield of maize and legumes. Cropping patterns induced no significant effect on soil chemical properties and either stover or grain yield. Estimated indices like land equivalent ratio (1.18–2.67) and competitive ratio index (0.01–1.72) confirmed the advantage of intercropping against sole cropping. This is largely supported by the estimated values of aggressivity and relative crowding coefficient. Smallholder farmers can therefore benefit by adopting CA.