Forest spatial heterogeneity and palm richness, abundance and community composition in Terra Firme forest, Central Amazon

Abstract

-(Forest spatial heterogeneity and palm richness, abundance and community composition in terra firme forest, Central Amazon). The mechanisms that maintain tree diversity in tropical rain forests are still in debate. Variations in forest structural components produce forest microenvironmental heterogeneity, which in turn may affect plant performance and have been scarcely analyzed in the Amazon. Palms are widespread in the Neotropical rainforests and have relatively well known taxonomy, apart from being ecologically and economically important. The understanding of how palms respond to variation in the forest structural components may help to explain their abundance and richness in a given area. In this study, we describe a palm community and analyze how it is affected by forest microenvironmental heterogeneity. In a pristine "Terra Firme" forest at Reserva Ducke, Manaus, we recorded all adult palm trees in twenty 100 × 10 m plots. In the same plots we recorded the variation in canopy openness, the leaflitter thickness and counted all non-palm forest trees. A total of 713 individuals in 29 palm species were found. The three most abundant species were Astrocaryum sciophilum (Miq.) Pulle, A. gynacanthum Mart. and Attalea attaleoides (Barb. Rodr.) Wess. Boer. The most locally abundant species were also very frequent or occurred in a larger number of plots. There were no significant effects of litter depth, forest canopy openness and forest tree abundance on palm richness. However, in areas where leaf litter was thicker a significant lower number of palm trees occurred. In microsites where proportionally more incident light was reaching the forest understory, due to higher canopy opening, significantly more palm trees were present.Key words -Amazonia, canopy openness, leaf litter, palm community, Reserva Ducke RESUMO -(A heterogeneidade espacial da floresta e a riqueza, abundância e composição da comunidade de palmeiras em floresta de terra firme na Amazônia Central). Os mecanismos que mantêm a diversidade de plantas em florestas tropicais estão ainda em debate. Variações nos componentes estruturais da floresta produzem heterogeneidade microambiental na floresta, que por sua vez devem afetar as plantas, e raramente têm sido analisados na Amazônia. As palmeiras são amplamente distribuídas em florestas neotropicais e tem a sua taxonomia bem conhecida, além de sua importância ecológica e econômica. O entendimento de como as palmeiras respondem às variações nos componentes estruturais da floresta pode ajudar a explicar a abundância e a riqueza delas em uma dada área. Neste estudo descrevemos uma comunidade de palmeiras e analisamos como ela é afetada pela microheterogeneidade ambiental da floresta. Em uma floresta de terra firme na Reserva Ducke, Manaus, registramos todas as palmeiras adultas em 20 parcelas de 100 × 10 m. Nas parcelas também registramos a variação na abertura do dossel, a profundidade de folhiço e o número de árvores da floresta. Setecentos e treze indivíduos de 29 espécies de palmeiras foram reg...

Influences of forest structure and landscape features on spatial variation in species composition in a palm community in central Amazonia

“…This study also adds to the increasing evidence that suggests that the natural heterogeneity found within tropical forests affects the local composition of plant and animal communities. There are several examples of this with other taxa from the current study site (Banks & Cintra 2008, Castilho et al 2006, Cintra & Naka 2012, Cintra et al 2005, Mendonça et al 2005, Menin et al 2007.…”

Effects of climate and forest structure on palms, bromeliads and bamboos in Atlantic Forest fragments of Northeastern Brazil

“…A number of factors affect palm community at local and regional scale in tropical forests, such as soil physical and chemical characteristics, topography (slope and altitude), climate, hydrology and components of forest structure (Cintra et al, 2005;Costa et al, 2009;Eiserhardt et al, 2011;Emilio et al, 2014;Rodrigues et al, 2014;Schietti et al, 2014). The greater abundance of palms in forests with a given structure can be a result of specific preferences of the local species (Eiserhardt et al, 2011).…”

Forest Structure, Plant Diversity and Local Endemism in a Highly Varied New Guinea Landscape

“…(Makua or Nara) and Terminalia spp (Terminalia). The shrub layer is dominated by scrambled bamboo, Maniltoa psilogyne, and a variety of lianas and palm species that may be maintained by relatively high light and semi-dry conditions of the understory [46][47]. The rarity of herbaceous forms may also be related to such dry environmental conditions.…”