Location: Soil Dynamics ResearchTitle: Nitrogen, phosphorus, and potassium requirements for Eucalyptus urograndis plantations in southern Brazil
|BASSACO, MARCOS - Universidade Federal Do Parana|
|MOTTA, ANTONIO - Universidade Federal Do Parana|
|PAULETTI, VOLNEI - Universidade Federal Do Parana|
|Prior, Stephen - Steve|
|NISGOSKI, SILVANA - Universidade Federal Do Parana|
|FERREIRA, CARLA - Universidade Federal Do Parana|
Submitted to: New Forests
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/22/2018
Publication Date: 8/24/2018
Citation: Bassaco, M.V., Motta, A.C., Pauletti, V., Prior, S.A., Nisgoski, S., Ferreira, C.F. 2018. Nitrogen, phosphorus, and potassium requirements for Eucalyptus urograndis plantations in southern Brazil. New Forests. 49:681-697. https://doi.org/10.1007/s11056-018-9658-0.
Interpretive Summary: Eucalyptus plantings have increased in southern Brazil, but fertilization practices have not been thoroughly evaluated. This study looked at how Eucalyptus urograndis would respond to different levels of N, P, and K in two regions in the southern Parana state of Brazil. Five rates of N and P2O5 (0, 30, 60, 120, and 240 kg ha-1) and K2O (0, 35, 70, 140, and 280 kg ha-1) were tested for tree growth response. Added N did not influence growth since N needs were met by existing organic sources. Both P and K additions improved tree growth. Study results suggest that new eucalyptus plantations in southern Brazil could benefit from P and K fertilizer but not from N fertilizer.
Technical Abstract: Although areas planted with eucalyptus have increased under the subtropical conditions of southern Brazil, fertilization has followed practices from nearby tropical regions. The objective of this study was to determine the response of Eucalyptus urograndis to N, P, and K in two regions of Parana (Jaguariaíva and Ventania) on a sandy oxisol following two harvest cycles of Pinus taeda. After site preparation, five rates of N and P2O5 (0, 30, 60, 120, and 240 kg ha-1) and K2O (0, 35, 70, 140, and 280 kg ha-1) were separately tested. Treatment response was evaluated by determining maximum technical efficiency (MTE), height (H) and diameter at breast height (DBH) at 3, 6, 9, 12, 18, 24, 30, and 36 months after planting, and volume at 36 months. At all assessments, N additions did not influenced growth parameters indicating that N demands were met by organic matter/litter mineralization. Phosphorus enhanced growth until the 18th month, with maximum gains at months 9 and 6 for Jaguariaíva and Ventania (56% and 59% of DBH for the 240 kg ha-1 P2O5 rate, respectively). Potassium improved growth only after the 24th month; maximum rate occurred at 200 kg ha-1 of K2O with a volume of 163 m3 ha-1 at the Jaguariaíva site. In conclusion, findings indicated that Eucalyptus urograndis grown in southern Brazil would be responsive to P and K fertilization, but not to the addition of N fertilizer.