Pattern and spatial associations of commercial trees in the Amazon

Brenda Letícia Rodrigues,Josiane Silva Costa Bruzinga,João Ricardo Vasconcellos Gama,Evandro Luiz Mendonça Machado,Marcio Leles Romarco De Oliveira,Renato Bezerra Da Silva Ribeiro

doi:10.1590/0103-8478cr20200367

Abstract

ABSTRACT: This study was conducted to establish the pattern and the spatial associations of the Amazon commercial tree groups. In a region extending across 2,000 ha in the Tapajós National Forest (FNT), Pará, a forest census was conducted. The census included commercial trees of perimeter at breast height (PBH), equal to or greater than 158 cm and the Cartesian coordinates of their bearings. Using Ripley’s K function, the spatial pattern was discerned, with 5 m radius being assumed, and maximum distances varying up to 1,500 m. Then, with 99.8% probability for both, 500 Monte Carlo simulations were performed for the univariate K function, and 500 toroidal simulations were done for the bivariate function.The commercial tree groups, which revealed an aggregated spatial pattern in a minimum of approximately 50% of the analysis distance were namely, Astronium lecointei, Bagassa guianensis, Couratari guianensis, Manilkara huberi, Mezilaurus itauba, and Vochysia maxima. In Brazil, the commercial tree groups, based on the commercialization criteria for tropical trees show random and aggregated spatial patterns with associations of spatial independence.

Highlights

The spatial distribution of species is an effective tool that helps deduce the spatial dependence of species and their patterns of distribution, supplying crucial subsidies for sustainable forest management methods (PEREIRA et al, 2006)
COMFLONA is situated in the Tapajós National Forest (FNT), in the Belterra municipality, in the state of Pará, Brazil, extending across an area of 527,319 ha, lying between the geographical coordinates of 2o 45’ and 4o 10’ “S” and 54o 45’ and 55o 30’ “W” (ICMBio, 2019) (Figure 1)
The commercial tree groups, including the species A. lecointei, B. guianensis, C. guianensis, M. huberi, M. itauba and V. maxima revealed the aggregated pattern, when the value was equal to or greater than 50% of the distance analyzed

Summary

Introduction

The spatial distribution of species is an effective tool that helps deduce the spatial dependence of species and their patterns of distribution, supplying crucial subsidies for sustainable forest management methods (PEREIRA et al, 2006). In northern Roraima, in the Amazon, the Alexacanaracunensis population growing in a seasonal semi-deciduous submontane forest displayed a regular pattern (OLIVEIRA et al, 2018), while in Floresta de Várzea, the Carapa spp. Adult trees were found in an aggregated spatial distribution pattern (ABREU et al, 2014). The Cabraleacanjerana, observed in a deciduous Seasonal Forest, shows an aggregated type of dispersion (ZIMMERMANN et al, 2014).NASCIMENTO et al, (2001) and SILVESTRE et al, (2012) in their examination of the whole community in a Mixed Ombrophilous Forest, identified a prominent aggregated distribution.

Methods

Results

Conclusion