Effects of Fertilization, Soil Texture, and Forking on the Wood Quality and Yield of Energy Plantations of Tachigali vulgaris in Amazonia

Biomass from planted forests is a renewable energy source with the potential to replace fossil fuels. Tachigali vulgaris wood shows potential for energy applications, but studies on fertilization and stem-type effects remain limited. This study evaluated the influence of stem type, soil texture, and fertilization on the energy potential and wood quality of T. vulgaris. The research was conducted in two experimental plantations in Pará, Brazil, on sandy loam and very clayey soils, with 11-year-old trees in four blocks per area. Three fertilization treatments with phosphorus and potassium were applied. Wood basic density (WBD), proximate analysis, heating value, extractive content, lignin content, wood dry mass, lignin mass, and wood energy productivity (EP) were measured. Fertilization treatments did not significantly affect the WBD, with a 0.514 g/cm³ average. However, every 2 cm increment in equivalent diameter (EqD) corresponded to a 0.01 g/cm³ rise in WBD. Trees with an EqD below 15 cm had WBD below 0.500 g/cm³. Higher fixed carbon (16.31% on a dry mass basis) was observed in very clayey soils. The treatments and their interactions significantly influenced extractives (4.65% dry basis), insoluble lignin (29.43% extractive-free dry basis, efdb), and total lignin (31.34% efdb). EP varied between 1739.23 and 2760.07 GJ/ha, with higher values for larger EqD. Growth parameters, including EqD, significantly influenced EP, with a 2.65 GJ/tree average. These findings highlight the importance of growth characteristics in evaluating species for energy forestry.

Graphical Abstract