Data/hora: 09/06/2024 13:35:50

Provedor de dados: 	36	
País: 	Brazil	
Título: 	Allometric models to estimate tree height in northern Amazonian ecotone forests	
Autores: 	BARBOSA,Reinaldo Imbrozio; RAMÍREZ-NARVÁEZ,Perla Natalia; FEARNSIDE,Philip Martin; VILLACORTA,Carlos Darwin Angulo; CARVALHO,Lidiany Camila da Silva.	
Data: 	2019-04-01	
Ano: 	2019	
Palavras-chave: 	Allometry; Amazon forest; Hypsometric relationships; Dendrometry; Seasonal forest.	
Resumo: 	ABSTRACT Allometric models defining the relationship between stem diameter and total tree height in the Amazon basin are important because they refine the estimates of tree carbon stocks and flow in the region. This study tests different allometric models to estimate the total tree height from the stem diameter in an ecotone zone between ombrophilous and seasonal forests in the Brazilian state of Roraima, in northern Amazonia. Stem diameter and total height were measured directly in 65 recently fallen trees (live or dead). Linear and nonlinear regressions were tested to represent the D:H relation in this specific ecotone zone. Criteria for model selection were the standard error of the estimate (Syx) and the adjusted coefficient of determination (R²adj), complemented by the Akaike Information Criterion (AIC). Analysis of residuals of the most parsimonious nonlinear models showed a tendency to overestimate the total tree height for trees in the 20-40 cm diameter range. Application of our best fitted model (Michaelis-Menten) indicated that previously published general equations for the tropics that use diameter as the independent variable can either overestimate tree height in the study area by 10-29% (Weibull models) or underestimate it by 8% (climate-based models). We concluded that our site-specific model can be used in the ecotone forests studied in Roraima because it realistically reflects the local biometric relationships between stem diameter and total tree height. Studies need to be expanded in peripheral areas of northern Amazonia in order to reduce uncertainties in biomass and carbon estimates that use the tree height as a variable in general models.	
Tipo: 	Info:eu-repo/semantics/article	
Idioma: 	Inglês	
Identificador: 	http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0044-59672019000200081	
Editor: 	Instituto Nacional de Pesquisas da Amazônia	
Relação: 	10.1590/1809-4392201801642	
Formato: 	text/html	
Fonte: 	Acta Amazonica  v.49 n.2 2019	
Fonte: 	info:eu-repo/semantics/openAccess