Influence of the presence of Eucalyptus spp. In the diversity and dynamics of nutrients in the natural regeneration process of the Ombrophilous DenseMontana Forest in the Atlantic ForestThe remnants of the Atlantic Forest are largely in the process of forestry secondaryization. The choice of strategies for the recovery of these ecosystems has been one of the biggest current challenges. Regeneration without human interference and the use of abandoned plantation forests to promote regeneration are among the most widely used strategies. This research aimed to analyze the development of tree diversity and nutrient dynamics in natural regeneration without human interference from the Ombrophilous Dense Forest at 3 different ages (8 (Rr), 20 (Rm) and 40 Ra), from abandoned pasture, and under Eucalyptus spp. with the same abandonment ages (Er, Em and Ea, in increasing age order). This mosaic of regenerating areas, as well as pasture (P) and Forest with no recent history of human use (F), used as a reference, can be found in the Jurupará State Park (Ibiúna / SP / Brazil). For the analysis of the evolution of biodiversity, botanical identification was carried out and phytosociological and dendometric parameters of regenerating communities were measured. 85 species belonging to 26 botanical families were identified. In all regenerations, the zoochoric dispersion predominated and in F and in the eucalyptus areas the relative frequency of non-pioneers was higher. The floristic similarity between F, Ra and Rm was greater than 50%, as well as between Er and Ea, by the Sorensen coefficient. Considering the Bray-cutis distance, the communities with the closest composition were similar, highlighting that Ra is closer to F when considering the relative abundance of species. The measures of wealth and diversity show an increase from Rm to F and from Er to Ea, with Er and Rr showing no difference. Regarding the structure, the total abundances, density and basal area did not differ between F, Ra and Rm, with the other regenerations being higher. Rr and Er also did not differ from each other, having the lowest values, while Ea presents intermediate values between these two groups. The height of the trees in F was higher than the other regenerations. The canopy cover in Er was lower than in the other natural and eucalyptus regenerations. At the end of the least rainy season, there was no difference in canopy coverage between systems and at the end of the rain season, the canopy coverage in Er and Ea was significantly less than in F, Ra and Rm. The dynamics of nutrients were analyzed with the monthly sampling of the deposited phytomass, analysis of its macronutrients, quantification of the litter accumulated in the soil and of the decomposition rates and chemical analysis of soil fertility. By the chemical characterization of the soil the total aspects of acidity and base saturation demonstrate that they are soils of extremely low fertility. Pasture was the sampled system with the best indicators for these parameters. Forest soils mainta...