Physicochemical characterization of oxisol subjected to succession culture

ABSTRACT No-till farming is the practice closest to the concept of sustainable agriculture. The minimum soil movement and continuous contribution of crop residues to the farming system reduce erosion, mitigate the greenhouse effect, increase the organic matter content, and improve the physical and chemical quality of the soil. This study aimed to assess the effect of five-year succession cropping on the physical and chemical attributes of oxisol. The crops were sown for five consecutive years in the same plots, using a randomized block design in split plots with four replicates. The plots were crops grown in succession to soybean, namely Congo grass (Urochloa ruziziensis syn. Brachiaria ruziziensis), Congo grass intercropped with maize (Zea mays L.), pearl millet (Pennisetum glaucum), sorghum (Sorghum bicolor L.), maize, and slender leaf rattlebox (Crotalaria ochroleuca). The subplots were the following sampled soil layers: 0-5, 5-10, and 10-20 cm. The physicochemical attributes of these three soil layers were evaluated. Pearl millet cycled K efficiently, providing the soil with K concentrations equivalent to those of the K fertilization treatments. No single crop or intercrop increased the soil P concentration. Congo grass stood out for its ability to increase the Mg concentration. The 0-5 cm soil layer had the best physicochemical attributes based on the accumulated organic matter.