EFFECTS OF PLANTING SPACING ON BIOMASS ACCUMULATION, CHEMICAL, PHYSICAL AND ENERGETIC PROPERTIES IN A PLANTATION OF Eucalyptus tereticornis SM. IN COSTA RICA

Abstract

Background: The use of tree plantations for energy purposes has shown an increase in their use in tropical regions due to the rapid growth of the species and low cost of energy generation. This has led to the development of optimization studies of crop conditions in the last decade to generate high levels of biomass in the shortest possible time. However, the determination of the effect of spacing on physical, chemical and energy properties has not been clear for Eucalyptus tereticornis, which limits the development of plantations with optimal silvicultural conditions.

Results: The results showed that mortality ranged from 29 to 69 %, being the 1.0x2.0 m spacing the one that presented better yields with significantly higher diameter and height (9.13 cm and 14.17 m respectively) with a higher biomass accumulation (140.04 ton ha^-1 without treetop) concentrated mainly in the stem. The other two spacings presented statistically lower and non-significant values. On a chemical level, differences were only found in N, C and C/N ratio, being 1.0x2.0 m the spacing that showed significant values. With energetic properties, again the 1.0x2.0 m spacing showed higher calorific value, but also higher ash and volatile content.

Conclusions: The spacing of 1.0x2.0 m was the one that showed significant values in most of the variables, being the optimal spacing for the establishment of the species in the environmental conditions of the study.