The objective of this work was to evaluate the initial growth of outplanted Eucalyptus tereticornis in pure and mixed Mimosa caesalpiniifolia-Mimosa pilulifera stands and their effects on soil characteristics in Campos dos Goytacazes-RJ. Survival rates, height, ground level diameter and diameter at breast height were evaluated over 30 months. Soil characterization at 0-5 and 5-10 cm depths was carried out at 6 and 30 months after outplantings. The experiment was set up in a randomized block design with 4 replications, with 14 measurable plants per plot. Thirty months after outplantings, the mixed E. tereticornis-M. caesalpiniifolia stand showed higher survival (87%) and better performance for dendrometric measurements. In the mixed ouplantings, the soil C content was lower at the 5-10 cm depth. Contents of P, Ca and base saturation (%) were lower, while pH, N, Na, Al and H+Al showed higher values in all the outplanting systems. In pure and mixed with Mimosa caesalpiniifolia outplantings, K contents were lower at the 0-5 cm depth. Mixed E. tereticornis M. caesalpiniifolia outplantings caused reduction in effective CTC (Exchangeable Cation Capacity), sum of bases and Mg content
Reforestation; Mixed outplantings; Soil nutrients