Growth endangered tree species in forest recomposition areas

In Brazil, there is a large gap in studies related to protected native species, discouraging their use in plantations, and consequently, further favoring the reduction of their conservation. In this sense, this research aimed to analyze the biotic and abiotic factors that influence the initial establishment, in enrichment planting, of five endangered forest species. The planting areas are located in extensions covered by secondary forest in the municipality of Vitória do Xingu/PA. The total perimeter outlined for enrichment with species corresponded to 147.26 ha. To evaluate the seedlings, 147 sample units of 800 m² were installed. The species survival inventory and height measurement were carried out 30 and 180 days after planting. The phytosanitary conditions of the seedlings, fauna vestige, soil fertility, herbaceous layer, and neighboring trees were evaluated. Among the main results obtained, the following stand out: (i) Cedrela odorata was found to have the highest mortality rate; (ii) Apuleia leiocarpa was the species that showed the highest absolute growth rate with a significant difference concerning Bertholletia excelsa; (iii) higher mortality was recorded at 30 days than in the second evaluation; (iv) the presence of animals inside the plots influenced seedling mortality; (v) the variability in the number of soil nutrients among the plots was not sufficient to generate different behavior among species; and (vi) the herbaceous layer and the surrounding trees did not promote any interference in the growth of the plants. It is recommended to use the species evaluated in this study in enrichment plantings.