6 research outputs found

    The woody flora and soils of seven Brazilian Amazonian dry savanna areas

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    This study compares the soils, floristic composition, phytosociological structure and history of seven Brazilian savannas in the Amazon basin: those at Alter do Chao, Amapa, Roraima and SE Humaita are islands in rain forest; and those at Chapada dos Parecis, Redencao, and Carolina are on the periphery (northern border) of the central Brazilian savannas (the so-called 'cerrado'). A total of 26 transects were sampled by the PCQ method (for trees with dbh greater than or equal to 5 cm) and additional tree species were recorded by 'wide patrolling'. A total of 101 species were recorded from the transects and another 43 species were recorded by 'wide patrolling'. Byrsonima crassifolia, B. coccolobifolia, Curatella americana, Salvertia convallariodora and Plathymenia reticulata occurred in most or all sites, but no species occurred in all transects. The number of species in the isolated savannas decreased with the distance from the central Brazilian core savanna area. Both cluster analysis (based on the S0rensen Similarity Index) and ordination (DCA), showed that the disjunct and non-isolated peripheral areas were in floristically distinct groups. Five surface soil samples (0 - 10 cm) were collected from each of the 26 transects. Two soil cores (up to 4 m depth), one located in the savanna and the other from the nearest forest present, were taken from each study site for carbon isotope analysis. All the sites had acidic soils (pH 4.5 - 5.2) and a wide range of concentrations of aluminium (0.12 - 1.49 meq 100g-1); most of the other soil properties varied significantly within study sites. An ordination (PCA) distinguished the soils from Amapa, Alter do Chao, Redencao and Roraima, but did not distinguish the disjunct sites from non-isolated peripheral ones. The soil delta 13C values of all the disjunct savannas indicated a vegetation change in the past from C3 to C4 plants, showing that forest (or at least a vegetation with few C4 plants) formely covered these sites. 14C dating indicated that the disjunct savannas are of relatively recent origin, e.g. Humaita was dated at about 2,000 years BP, and hence that they are not remnants of a more widespread Pleistocene savanna in the Amazon

    Habitat quality, not patch size, modulates lizard responses to habitat loss and fragmentation in the southwestern Amazon

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    As deforestation frontiers expand in the tropics, understanding species responses is critical to inform efficient land-use management policies. Here we evaluated lizard responses to changes in landscape, habitat patch, and quality in a deforestation frontier in southwestern Brazilian Amazonia. We first considered overall lizard assemblages and then two species subgroups of contrasting thermoregulation strategies. We sampled lizards at 21 forest patches (42-7,035 ha) subject to moderate habitat disturbance (e.g., cattle intrusion and selective logging). Based on 6,000 pitfall trap-days and 60,000 m of visual surveys, we recorded 215 individuals representing 15 species. Contrary to expectations, species richness and abundance were not explained by any of the variables considered, including matrix quality, proportion of forest cover, forest patch area and shape, age since isolation, arthropod biomass, canopy openness, litter volume, tree density, and fire history. However, the composition of persisting species was determined by the structural complexity of the adjacent matrix. The abundance of species that avoid direct sun exposure to regulate their body temperature increased under more-complex structures of adjacent matrix areas and decreased within patches more intensively affected by past fire events. Disturbance within forest patches likely decreased the patch-matrix contrast, contributing to the absence of forest area effects. Nevertheless, species-specific microhabitat requirements dictated part of the lizard species that were able to persist in the fragmented landscape. Strategies aiming to maximize lizard diversity should embrace retention of the habitat quality within forest patches and forest corridors/high-stature vegetation in at least some sites connecting forest remnants

    Ex situ population of the Harpy Eagle and its potential for integrated conservation

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    A main priority in conservation is the protection of species in their natural habitat. However, ex situ management of threatened species is a recognised strategy of conservation. Harpy Eagles (Harpia harpyja) are removed from the wild due to illegal capture, nest tree destruction, or other conflict sources. This study presents a review of the current ex situ Harpy Eagle populations in Brazil and worldwide, including information on the origin, sex, and year of entrance or year of birth under human care. Worldwide, until 2020 there were 205 Harpy Eagles in 77 different facilities in 16 countries, with 40 institutions in Brazil and 37 in other countries. The largest ex situ Harpy Eagle population is maintained in Brazil, with 139 individuals (75 females and 64 males) in 40 institutions. Of these institutions, there were 24 zoos, seven conservation breeding centres, six commercial breeders, two wildlife shelters, and one wildlife sorting centre. In Brazil, 62% (n = 86) of the individuals were hatched in the wild and 38% (n = 53) were bred in captivity under human care; for the wild individuals, only 73% (n = 64) have a known state of origin, with the majority from Pará state. This investigation provided relevant information to establish an ex situ demographic database. These individuals may potentially constitute a genetically and demographically viable safety population for future conservation strategies, as well as a source for research and education applied to Harpy Eagle integrated conservation

    AMAZONIA CAMTRAP: A data set of mammal, bird, and reptile species recorded with camera traps in the Amazon forest

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    The Amazon forest has the highest biodiversity on Earth. However, information on Amazonian vertebrate diversity is still deficient and scattered across the published, peer-reviewed, and gray literature and in unpublished raw data. Camera traps are an effective non-invasive method of surveying vertebrates, applicable to different scales of time and space. In this study, we organized and standardized camera trap records from different Amazon regions to compile the most extensive data set of inventories of mammal, bird, and reptile species ever assembled for the area. The complete data set comprises 154,123 records of 317 species (185 birds, 119 mammals, and 13 reptiles) gathered from surveys from the Amazonian portion of eight countries (Brazil, Bolivia, Colombia, Ecuador, French Guiana, Peru, Suriname, and Venezuela). The most frequently recorded species per taxa were: mammals: Cuniculus paca (11,907 records); birds: Pauxi tuberosa (3713 records); and reptiles: Tupinambis teguixin (716 records). The information detailed in this data paper opens up opportunities for new ecological studies at different spatial and temporal scales, allowing for a more accurate evaluation of the effects of habitat loss, fragmentation, climate change, and other human-mediated defaunation processes in one of the most important and threatened tropical environments in the world. The data set is not copyright restricted; please cite this data paper when using its data in publications and we also request that researchers and educators inform us of how they are using these data
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