Growing up at Different Altitudes: Changes in Energy Content of the Abies religiosa Wood

Wood is considered an important renewable energy resource with a variable elemental chemical composition, which may change according to environmental conditions (e.g., temperature, precipitation, altitude). In this study, we evaluated how heating value (HV), elemental chemical composition, and main thermoenergetic parameters of Abies religiosa wood change along an altitudinal gradient. To evaluate these parameters, wood samples were collected from six independent trees in an altitudinal gradient (3000-3500 masl) every 100 m of altitude (36 trees) and their respective HV (higher and low), thermogravimetric and immediate analysis, specific carbon energy (SCE), and fuel value index (FVI) were determined. We found that the higher and lower heating values, elemental chemical composition and the majority of the studied parameters were significantly different (p < 0.05) between altitudes. Our results suggest that A. religiosa wood from 3300 masl has more energy content than wood from 3200 and 3500 masl. Additionally, FVI showed that wood from 3500 masl is the best feedstock in order to use as a solid biofuel. Finally, the results suggest that the altitude at which A. religiosa is grown significantly affects the energetic content of their wood and throughput as a solid biofuel