Floristic composition, diversity and edaphic effects in two rocky savanna communities in the Amazon and Cerrado, Brazil

Abstract

Despite the uniqueness and reach of the flora from natural savannas in the Brazilian Amazon, and the existence of studies on its origin and diversity, there are no local studies associating floristic patterns with soil properties in savanna enclaves in the Amazon region of the state of Mato Grosso. Floristic composition and diversity were compared between a woody community from a rocky savanna inselberg in a transition region (RTS) between the two largest South American biomes (Cerrado-Amazon), and an enclave of rocky savanna in the Amazon (RAS), and the effects of soil properties were investigated. Floristic comparisons were also made between the two studied communities and two other rocky savanna communities near the Cerrado-Amazon transition. The flora and physical and chemical soil properties in twenty-five 20 × 20 m subplots (1 ha) in each community were sampled and georeferenced. An evident floristic distinction was found between the two studied communities, with low similarity values and a high number of indicator species. The observed and estimated richness and Rényi diversity profiles indicated lower species diversity in RAS than in RTS. Soils were found to be litholic, poorly drained, dystrophic, alic, extremely acidic, sandy and nutrient poor. Species composition and abundance was associated with soil properties in both communities. The clear difference in species composition and diversity between RTS and RAS seem to be shaped by soil properties, geographic isolation and floristic influence from the Cerrado and the Amazon. These results broaden the knowledge regarding the composition and diversity of woody plants of savannas in Amazonian enclaves and Cerrado inselbergs, and provide an important set of floristic and edaphic descriptors for the phytogeography of rocky savannas.

High diversity of anatomical and hydraulic strategies of dominant Amazonian savanna woody species

“…The study was conducted in a rocky Amazonian savanna community in the municipality of Nova Canaã do Norte in the state of Mato Grosso, Brazil (Figure 1), 10º53'98,7" S, 55º46'68,7" W). The soil of the study area is classi ed as Litholic Neosols that are poorly drained, dystrophic, alic, extremely acidic and sandy, and with low nutrient concentrations (Pessoa et al, 2021). The climate of the area is equatorial (Am) hot and humid, according to the Köppen classi cation, with temperatures varying from 20° C to 36° C with an annual average above 28° C (Alvares et al, 2013).…”

A review of pollen types foraged by Melipona in the Brazilian Amazon

“…Thus, knowledge of beekeeping flora can help establish the productive potential and define the management possibilities of meliponaries and bees, which must respond to the particularities of the ecosystems in which they are inserted (Lopes et al 2011). The diversity of plants visited by bees depends on the available floral resources (Marques-Souza et al 1995; Ferreira and Absy 2015; Pimentel et al 2021), which in turn are influenced by some factors, such as the time of year and the temporal extension of the observation as most tropical plants flower seasonally (Morellato et al 2013), the vegetation type (Pessoa et al 2021) and environmental characteristics, as the diversity of a vegetation type can change throughout the environmental gradient (Wittmann et al 2006). Factors linked to sampling methods also be considered, as the methods influence the results, both in the bee diversity (Prendergast et al 2020) and bee flora diversity (Cane and Sipes 2006; Ferreira et al 2021).…”