Carbon and nitrogen stocks under different management conditions of a yellow-red ultisol, cultivated with sweet corn in Sergipe coastal tablelands

Abstract

This study was carried out in a long term experiment and aimed to evaluate the effects of different tillage systems associated with cover crops following sweet corn (Zea mays L.) cultivation on soil C and N stocks. The soil was a red-yellow Ultisol, characteristic of the coastal tableland in the estate of Sergipe. Experimental bands over a split plot scheme were set up with 12 treatments: three management systems (conventional tillage (CC), reduced tillage (CM) and, No-tillage (PD), in the plots, and four cover crops (peanut (Arachis hypogeae), common bean (Phaseolus vulgaris), pigeon pea (Cajanus cajan) and, crotalaria (Crotalaria juncea), in the subplots, with three replications. The highest soil organic carbon input was observed on the No-tillage system as compared to the other tillage systems. As far as N content is concerned, both No-tillage and reduced tillage systems contributed the most. Notillage system associated with cover crops such as Common bean, Peanut and Pigeon pea contributed to a higher soil organic carbon stock while higher N stock was observed when Pigeon pea was associated with reduced tillage system. No-tillage and reduced tillage systems presented higher C and N stocks, respectively, when compared to conventional tillage, improving agriculture sustainability.