Dinâmica do n-mineral em pastagem de coastcross consorciado com Arachis pintoi com ou sem nitrogênio em duas estações do ano

Abstract

This trial was carried out to evaluate nitrogen dynamics on soil profile, on a Coastcross pasture mixed ornot with Arachis pintoi, fertilized or not with N, using a randomized block design with four replications in four treatments, as follow: (CA) Coastcross + Arachis without N; (CA+100N) Coastcross + Arachis with100 kg of N; (C+200N) Coastcross with 200 kg of N and (CA+200N) Coastcross + Arachis with 200 kg of N. The evaluations were conducted in spring and summer and studied by a regression analysis. It was collected five soil samples in each paddock on 0-0,2; 0,2-0,4; 0,4-0,6; 0,6-0,8 and 0,8-1 m depth. This operation was made no longer than 15 days, after nitrogen fertilization and 20 to 30 mm rainfall precipitation. The results showed that the highest mineral-N was on the most superficial soil layers,decreasing with the increase of soil depth, mainly on treatments containing legume, which presented a higher nitrogen retention capacity