Abstract One of the biggest problems in the estimation of aboveground biomass at the global level is the choice of a correct allometric model. In Mexico, there is a need to quantify the biomass of species in arid zones. For this reason, the objectives of this work were to adjust allometric equations for estimating biomass of Prosopis using a bayesian approach (EB) and to quantify the error in the adjustment of the models: EB, Ordinary Least Squares (OLS) and one get from a research published in 2012. The Bayesian model was developed on the basis of probability distributions of parameters (a and b) a priori, collected from seven experimentation sites in which we estimated the biomass (B) through basal diameter (Db) using power equations. We compared the approaches in five sizes of samples (TM) (10, 30, 60, 90 and 120); in each of them, 1000 repetitions without replacement were carried out. The 144 trees measured in the sampling sites were used to validate the setting for each sub-sample. The results showed that the EB presented the lowest error variability in the different TM. The MCO adjusted similar to EB, however its variability and the presence of outliers grew to decrease TM. The adjustment with the parameters of that research made in 2012 presented the greatest variability and demonstrated the high degree of uncertainty when estimating the biomass with fixed parameters. It is recommended the application of EB for the estimation of biomass in other species of interest and their application in national inventories.

Resumen Uno de los mayores problemas en la estimación de biomasa aérea es la elección de un correcto modelo alométrico. En México existe una necesidad de cuantificar la biomasa de especies en zonas áridas. Los objetivos de este trabajo fueron ajustar ecuaciones alométricas para estimar la biomasa de Prosopis laevigata mediante un enfoque bayesiano (EB) y cuantificar el error en el ajuste de los modelos: EB, mínimos cuadrados ordinarios (MCO) y el obtenido de una investigación publicada en 2012. El modelo bayesiano se desarrolló con base en distribuciones de probabilidad de parámetros (a y b) a priori, recopiladas de siete sitios de experimentación en los cuales se estimó la biomasa (B) a través del diámetro basal (Db) mediante ecuaciones potenciales. Se compararon los enfoques en cinco tamaños de muestra (TM) (10, 30, 60, 90 y 120); en cada una de ellas se realizaron 1000 repeticiones sin remplazo. Los 144 árboles medidos en los sitios de muestreo fueron usados para validar el ajuste para cada submuestra. Los resultados mostraron que el EB presentó la menor variabilidad del error en las distintos TM. El MCO ajustó similar a EB, sin embargo, su variabilidad y la presencia de valores atípicos crecieron al disminuir TM. El ajuste con los parámetros de la investigación publicada en 2012 presentó la mayor variabilidad y demostró alta incertidumbre al estimar la biomasa con parámetros fijos. Se recomienda la aplicación de EB para la estimación de biomasa en otras especies de interés y su aplicación en inventarios nacionales.

Foram registrados vários eventos de reutilização de ninho ou do sítio de nidificação dentro e entre estações reprodutivas por Lathrotriccus euleri, Leptopogon amaurocephalus e Mionectes rufiventris em fragmentos de floresta do sudeste do Brasil. A reutilização do ninho ou do sítio de nidificação ocorreu entre estes tiranídeos e foi freqüente dentro de uma única estação reprodutiva para L. amaurocephalus. A reutilização do ninho, contudo, não foi relacionada ao sucesso das tentativas anteriores. As taxas de retorno ao ninho foram baixas para L. amaurocephalus, intermediárias para L. euleri e altas para M. rufiventris.

Nest and or nest site reuse within and between breeding seasons was reported by the Euler's Flycatcher (Lathrotriccus euleri), the Sepia-capped Flycatcher (Leptopogon amaurocephalus) and the Gray-hooded Flycatcher (Mionectes -rufiventris) in forest fragments from southeastern Brazil. Nest and or nest site reuse between some years was frequent within a single breeding season by the Sepia-capped Flycatcher. Nest reuse, however, was not related to nesting success in the previous breeding attempt. Nest turnover rates (movement to a new site between years) were low for L. amaurocephalus, intermediate for L. euleri and high for M. rufiventris.