Equivalencia entre modelos alométricos y alometría pantropical flexible
DOI:
https://doi.org/10.21829/myb.2021.2742444Palabras clave:
bosques tropicales, densidad de la madera, modelos generales, relación entre constantes y exponentes, transformación logarítmicaResumen
La estimación de la biomasa aérea total en bosques tropicales es una tarea crítica para la gestión forestal y los mercados del carbono. Los modelos pantropicales multiespecies y multisitios tratan de desarrollar estimaciones para el caso general de falta de conocimiento de modelos locales específicos. Bajo un enfoque algebraico simple, este trabajo presenta las equivalencias entre los modelos analizados, los cuales son parametrizados por regresión lineal simple en el espacio log-log mediante una base de datos pantropical (bosques tropicales), con 4004 mediciones en 58 sitios en el mundo; incluye mediciones del diámetro a la altura del pecho (D) y altura total (H), así como estimaciones de la densidad de la madera (ρ). Los resultados soportan la equivalencia de los modelos alométricos. Adicionalmente se realizó una parametrización de los modelos alométricos usando la base de datos pantropical a través de regresión lineal simple de las transformaciones logarítmicas de los modelos. El modelo que usa D, H y ρ a nivel local (clases de densidad o sitios) resulta en la estimación con menor error. El modelo alométrico pantropical estimado se propone como un modelo global; aunque con una discusión sobre su aplicabilidad con relación a los modelos locales. Una aproximación al modelo global es introducida al parametrizar un modelo en función de la densidad de la madera y dos enfoques con relación al exponente de la relación potencial analizada. Los modelos pantropicales desarrollados muestran estimaciones ligeramente mejores que el modelo pantropical, dando flexibilidad al error de estimación al asociarlo a la densidad de la madera de las especies de árboles.
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