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Dieta frugivora de Tapirus terrestris e deposição de fezes: contribuição para a dispersão de sementes e regeneração de florestas, Amazônia Central, AM
(Instituto Nacional de Pesquisas da Amazônia - INPA, 2006)
Morais, Adriane Aparecida de
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Gribel, Rogério
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Rodrigues, Mauro Galetti
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Fragoso, Jose Manuel Vieira
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Ferreira, Marco Aurelio Pizo
Tapirus terrestris (tapir) is the biggest terrestrial Neotropical mammal. It is classified as frugivorous – grazer, it feeds on vegetables, and fruits correspond to 33% of its diet. It is capable of ingesting some seeds without harming them; consequently it promotes its dispersion. Tapirs are appreciated as a feeding source for the human populations in the Amazon and very little was studied about the species in the Central Amazon. The aim of this study was to determine the tapir’s frugivore diet during the dry season, and to analyze, through feces deposition, the contribution of these animals to the dispersion of seeds and regeneration of damaged forests. The study was carried out in an area free of poaching activities, aiming gathering data that may collaborate to the effective preservation and maintenance of the ecological process that this species promote. During the beginning of the dry season of 2005, from May to July, 113 samples of tapir feces were collected. Forty eight morphospecies of seeds were found, from which, 39 were identified at a precise taxonomic level. The family found in 100% of the samples was the Melastomataceae , because the species Bellucia sp1 was found in all the feces samples. The family Leg. Mimosoideae was the second family more abundant (40%), which the fruits were bean like, Passifloraceae (13%) was the third family, which has fruits with succulent drupes. From the 113 samples of tapir feces containing seeds, 56 were found in scrub areas. 30 were found below and 27 in plateau areas. The number of morphospecies found in each area was of 34, 28 and 23, respectively. The tapirs preferred to use open areas during the months where the fruits were scarce in the forest, therefore, they transported a great variety of species to these areas which contributed to the regeneration of the environments. The number of species per feces sample had little variation in all the areas, and the multivariate analysis showed that there was no deposition pattern in the morphospecies per environment, which reflects the great mobility of these animals inside and outside the forests.
Regimes de turbulência noturna e a relação com a altura da camada limite noturna, jatos de baixos níveis e mortalidade de árvores na Amazônia
(Instituto Nacional de Pesquisas da Amazônia - INPA, 2026)
Mendonça, Anne Cristiny Santos de
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Dias Júnior, Cléo Quaresma
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Marra, Daniel Magnabosco
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Dias Júnior, Cléo Quaresma
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Souza, Rita Valeria Andreoli de
Turbulence plays a fundamental role in energy and mass exchanges between the forest and the atmosphere. However, during nighttime, reduced turbulence and increased atmospheric stability can lead to decoupling between the canopy and the atmosphere, making the structure of the Nocturnal Boundary Layer (NBL) particularly complex. In the Amazon, our understanding of how turbulence organization determines NBL height and how larger-scale phenomena, such as Low-Level Jets (LLJs) and convective systems, influence these dynamics remains limited, in part due to the scarcity of turbulence measurements with high vertical resolution. In this work, we investigated the organization of nocturnal turbulence above the forest canopy in Central Amazonia, its relationship with NBL height variability and LLJs, as well as the influence of downdrafts and extreme winds associated with tree mortality. We used high-frequency measurements collected at different heights above the canopy, including those obtained along the 325-m tower at the Amazon Tall Tower Observatory (ATTO), this unique observational setup allowed us to directly investigate the vertical structure of turbulence throughout the NBL, which had previously been studied using indirect approaches. The results revealed two distinct turbulence regimes, a very stable regime and a weakly stable regime. Transitions between these regimes were modulated by proximity to the canopy, seasonality, and the occurrence of downdrafts, which promoted coupling between the forest and the atmosphere. NBL height (hN), determined from vertical turbulence profiles, varied with atmospheric stability and surface roughness. In addition, hN was lower than previous estimates based on thermal inversion, indicating that indirect methods may overestimate hN. During nights with LLJs, the jet nose height did not universally represent hN. Under weakly stable conditions, it was consistent with hN, whereas under very stable conditions it was located above hN, showing that the use of LLJs as indicators of hN depends on the coupling state between the canopy and the atmosphere. The influence of downdrafts associated with convective systems was also investigated using ERA5 reanalysis data. The analysis of an event associated with a previously documented blowdown showed that the reanalysis reproduced the main thermal and dynamical patterns associated with the passage of the storm, although its resolution limited the representation of local gust magnitudes. The analysis revealed an intensification of extreme winds between 2005 and 2020, particularly during the wet season. Overall, the results show that the structure of the nocturnal atmosphere over the Amazon forest results from the interaction between local turbulent processes and larger-scale atmospheric forcing. These findings advance the understanding of the physical mechanisms controlling forest–atmosphere coupling and establish a connection between boundary-layer dynamics and atmospheric processes associated with tree mortality in the Amazon.
Albrecht, Rachel Ifanger
Grion, Lívia Souza Freire
Mendonça, Anne Cristiny Santos de