Biomass production and characteristics of short rotation plantations of clones of Gmelina arborea in three spacings

Abstract

The first attempts to establish energy crops in the tropical regi­on using short rotation species are premised on the utilization of clones for wood production. Therefore, the present study is aimed at examining the growth aspects (survival, diameter and tree height), leaf architecture (leaf area index [LAI], number and angle of the branches and sylleptic branches), biomass production, as well as biomass flow at the age of 24 months of two clones of Gmelina arborea in short rotation crops within three spacings (1.0x1.0 m, 0.75x0.75 m and 1.0x0.5 m). The results showed an increment with age, as the diameter increa­sed from 3.00 cm at six months to 8.0 cm at 24 months, where­as the total height increased from 2.00 m at six months to 10.00 m at 24 months. Clone survival varied from 20 to 60 %, whereas the LAI, branch angle and sylleptic branches increased with age. The differences between clones appeared after 12 months. Biomass production was similar between clones, from 6 ton/ha at six months to 67 ton/ha at 24 months, with clone 2 showing greater biomass flow than clone 1. On the basis of biomass pro­duction results and the development of diameter as well as height, clone 1 is recommended for spacing 1.0x1.0 m and clo­ne 2 for spacings 0.75x0.75 m and 1.0x0.5 m.

Effect of planting density and tree species selection on forest bioenergy systems: tree growth, nutrient storage and wood chemical properties

“…The biomass distribution pattern is similar to that reported by Tenorio 19 and Ferrere 26 . The short‐rotation plantation tends to accumulate 60% of the biomass in the trunk, to a lesser extent in branches and leaves; this behavior is due to a nutritional optimization of the species.…”

“…that of branches that showed no differentiation between 12 and 24 months regardless of planting density; (iv) at 3 months, no differences in aerial biomass were found between planting densities; (v) after 12 months, the density of 10 000 trees ha − The biomass distribution pattern is similar to that reported by Tenorio 19 and Ferrere. 26 The short-rotation plantation tends to accumulate 60% of the biomass in the trunk, to a lesser extent in branches and leaves; this behavior is due to a nutritional optimization of the species.…”

“…Salazar 18 analyzed the caloric power of six trees and herbaceous species, and found that 25% of nutritional losses (N, P, and K) in the soil occur in the third cutting cycle. Tenorio et al 19 identified clones of Gmelina arborea that are optimal for energy cultivation when combined with the nonextraction of leaf cover, avoiding a significant degradation of soil nutrient levels (N and K). Searle and Malins 20 point out that nutritional management is required for cycles of less than 3 years in tropical species.…”

Efecto del espaciamiento en la estimación indirecta del índice de área foliar en plantaciones dendroenergéticas de Eucalipto

“…), desarrollaron ecuaciones de productividad anual de madera en función del IAF, encontrando un efecto significativo del espaciamiento. Por su parte, Tenorio et al (2019) identificaron los espaciamientos óptimos para dos clones de Gmelina arborea, maximizando la producción anual de biomasa con el mínimo IAF posible. Finalmente, Wengert et al (2021) determinaron el espaciamiento óptimo para el establecimiento de sistemas agroforestales que optimicen la relación IAF-crecimiento en especies arbóreas tropicales.…”

“…y Eucalyptus saligna SM. a partir de investigaciones previas desarrolladas por Valverde et al (2017), Tenorio et al (2019) y Valverde y Arias (2020). Se planteó como hipótesis que la reducción del espaciamiento produce un aumento significativo del IAF.…”