Influence of various intercropping systems on soil quality characteristics and their potential for climate change adaptation in Dedza, Malawi

Abstract

Malawi’s food security, mainly dependent on subsistence crop production by poor smallholder farmers, is seriously affected by the negative impacts of land degradation due to climate change and poor production practices. The effects of climate change and the increasing population also exacerbate the situation. As opportunities for land-extensive agricultural growth are reduced, modern production technologies such as intercropping have become essential for producing sufficient food for the country. The study aims to describe the effects of different cereal-to-legume intercropping systems on soil quality characteristics and crop yield for climate change adaptation in Dedza District, a case of Lobi Extension Planning Area (E.P.A.). Data on soil characteristics and crop yields were collected. The methodology involved soil sampling from 0–5 cm and 5–20 cm on the ridge, then 0–5 cm and 5–20 cm on the fallow from each plot, and later laboratory analyses for soil physical and chemical analyses. Results of one-way ANOVA showed that cereal-legume intercropping combinations in this study affected the soil chemical properties such as soil nitrogen, organic matter, particulate organic matter, and exchange capacity, which were higher in intercropping systems than monocropping (p < 0.05). However, the system did not affect the soil pH, K, P contents, soil moisture, and water infiltration characteristics (p > 0.05). Overall, the cereal and legume combination intercropping system had a significant and positive linear regression effect on crop yield (p < 0.001; R2 = 0.6325) with an average grain yield of about 357066.15 (kg/ha). These results indicate that the cereal and legume intercropping system positively influenced crop yield, encouraging smallholder farmers to consider cereal and legume crop combinations intercropping to improve soil chemical properties and boost crop productivity.