Nutritional sustainability in a Eucalyptus dunnii Maiden stand in the Pampa biome, RS

For the guidelines that promote the nutritional sustainability of forest stands and future maintenance of the productivity it is important to combine the eucalyptus species cultivation that are nutrient use efficient, and the intensity of biomass harvesting which maintains the largest stock of nutrients on the site. The objective of this study is to characterize nutrient use efficiency and nutritional sustainability at different intensities of the biomass harvested of a Eucalyptus dunnii stand cultivated in the Pampa biome. The nutrient use efficiency (NUE) and nutritional sustainability were determined through the number of harvests (NC), when harvesting the biomass (S1), removal of the wood with bark (S2) and harvesting of the stems (S3). As for NUE: it is higher for sulfur and phosphorus for the production of all biomass components, while the use of calcium is less efficient. As for harvest intensities: when adopting S1, there is not a sufficient stock of N for the conduction of the new cycle and all the nutrients must be replaced via mineral fertilization. When aiming at nutritional sustainability, it is recommended to harvest the stems only (S3), this will limit the future availability of calcium; however, there is an increase in the number of possible rotations in the site for all nutrients. © 2020 University of Sao Paolo. All rights reserved.