Ground-herb communities of terra firme riparian forests of the lower Tapajós River in the Brazilian Amazon

Abstract

We conducted an inventory of the fern, lycophyte and non-palm monocotyledon ground-herbs of terra firme riparian forests in the lower Tapajós region of the Brazilian Amazon. Eight 1.5 × 250 m plots, totaling 0.3 hectares, were surveyed along the watersheds of the Cupari and Curuá-Una rivers, located at the Tapajós National Forest, Pará, Brazil. To characterize the ground-herb community, we calculated species richness, abundance and Fisher’s alpha for each plot. To analyze turnover, we compared composition among plots by pairwise Bray-Curtis distance. In total, we sampled 3,130 individuals, 58 species, 27 genera and 20 families of riparian ground-herbs. Marantaceae (14 spp) was the richest family and Poaceae the most abundant family (738 individuals). The fern Triplophyllum glabrum (Tectariaceae) was the most frequent species, observed in 87.5 % of plots. Ground-herbs communities in the studied area have high species turnover, making it necessary to invest time and resources to adequately characterize and manage riparian habitats. The ground-herb community composition observed in the riparian zone here resembles that of other non-riparian forested sites in the Amazon with the plant families Marantaceae, Pteridaceae and Poaceae generally being the most commonly represented in the Amazonian ground-herb stratum. We highlight the importance of herb inventories, especially in conservation units.

Estrutura e composição de ervas terrestres em zonas ripárias na estação ecologica de Cuniã

“…As ervas ripárias são um importante componente das florestas de terra firme na ESEC Cuniã, dada a sua grande representatividade de espécies, aqui identificamos 54 espécies em 18 parcelas (somando 0,9 ha). As famílias mais ricas neste censo, ou seja, Marantaceae, Araceae, Poaceae e Heliconiaceae, estão entre as mais ricas em ambientes incluindo florestas ripárias e não ripárias da Amazônia Central e Oriental (COSTA, 2004;COSTA et al, 2005;COSTA, 2006;ZUQUIM et al, 2008;RODRIGUES et al, 2021).…”

“…As ervas terrestres são um componente importante do sub-bosque para o ecossistema florestal, apresentando grande proporção da sua biodiversidade de espécies, podendo contribuir com 14 a 40% da riqueza de espécies e 9 a 70% da abundância entre as espécies terrestres amazônicas (COSTA, 2004;DRUCKER et al, 2008;MAGALHÃES, 2010;RODRIGUES et al, 2021).…”