Dynamics of initial spacing on the diameter of hybrid Eucalyptus grandis x Eucalyptus urophylla in a systematic design

Autor: Mirella Basileu de Oliveira Lima, Thelma Shirlen Soares, Renan Augusto Miranda Matias, Kálita Luis Soares, Priscila Sales Rodrigues Aquino, Eder Pereira Miguel, Mauro Eloi Nappo, Ricardo de Oliveira Gaspar, Renato Vinícius Oliveira Castro
Rok vydání: 2021
Předmět:
Zdroj: March 2021. :422-430
ISSN: 1835-2707
1835-2693
DOI: 10.21475/ajcs.21.15.03.p2935
Popis: We evaluated the effect of initial spacing on the distribution of Eucalyptus grandis x Eucalyptus urophylla tree diameters in a Nelder wheel design. The study area was in west-central Brazil. A Nelder wheel design with three repetitions was used. This design provides 432 planting spots per plot/repetition. Planting density varied from 0.50 m² to 41.25 m². The diameter at breast height was measured for all plants every four months until 36 months of age, totaling eight measurements. The description of the diameter distribution was developed by fitting probability density functions for each spacing and age. The quality of fit was evaluated using the root mean square error percentage, Pearson’s correlation coefficient, and the Kolmogorov-Smirnov test (α < 0.05). The spacings up to 1.17 m² must be harvested in less than two years, since it is noted that in the third year the increment in diameter is static and the mortality rate increases. The spacing highly affects the diameter structure of the population, impelling the forester to consider different uses for the wood. For wood requiring larger diameters, spacing above 8.69 m² per tree is recommended
Databáze: OpenAIRE