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Local extinction of Scinax caldarum, a treefrog in Brazil’s Atlantic forest
No full textHere we report the local extinction of Scinax caldarum, an endemic tree frog species of the Brazilian Atlantic Forest. We also report a reduction of the geographic range of this species to less than 15 % of the area in which it occurred 27 years earlier. We consider the excessive use of agrochemicals to be the main factor explaining the decline, including in farms with environmental certification. The local extinction of S. caldarum is a bioindicator of the severe impact of crops such as coffee and sugar cane, which heavily rely on agrochemicals. Stricter regulation of pesticides is needed to avoid damage to ecosystems and loss of biodiversity. © 2019, British Herpetological Society. All rights reserved
Microwave processing of camu-camu juices: Physicochemical and microbiological parameters
No full textThe objective of this work was to evaluate microwave heating (MW) in the processing of camu-camu juices. A factorial design (22) with repetition at the central point was performed. We evaluated the effect of microwave power (310-940 W) and processing time (15-45 s) on physicochemical characteristics, reduction of enzyme activity (POD and PPO), microbiological quality and bioactive compounds content (DPPH, phenolic compound, ascorbic acid, and anthocyanins). Generally, the juices treated by MW presented better results in comparison to the conventional method. There were no significant changes in pH, titratable acidity, total soluble solids, and color parameter in camu-camu juices in comparison with untreated samples. The ascorbic acid content in the juices increased after the treatment by MW. A significant reduction of degrading microorganisms was observed for the treated juice in relation to the control juice. Microwave heating can be a good alternative for the treatment of Amazonian fruit juices. Practical applications: The global consumer market requires that foods be high in bioactive compounds to improve human health. The Amazon Rainforest is known worldwide for its rich biodiversity, mainly for its wide variety of foods rich in bioactive compounds. The lack of transportation infrastructure and basic sanitation in the region causes the food to present high microbial contamination that can accelerate food degradation, especially its bioactive compounds. The use of microwave heating may be an opportunity to offer a fast, efficient, and low-cost process for the reduction of microorganisms in fruit juices and pulps. This study is a pioneer in the use of emerging technologies in the conservation of Amazonian fruit juices, allowing a new opportunity for the food industry to offer products with high nutritional value. © 2019 Wiley Periodicals, Inc
Aparência ecológica e conservação de espécies lenhosas pelos makuxis nas savanas de roraima, amazônia brasileira
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Can environmental complexity predict functional trait composition of ground-dwelling ant assemblages? A test across the Amazon Basin
No full textEnvironmental gradients may influence species distributions by filtering their functional traits, resulting in a correspondence between community functional composition and local environmental conditions. We used a vegetation gradient as an indicator for environmental complexity to test whether it predicted the morphological composition of ground-dwelling ant assemblages across geographic extents. The sampling design covered 126 plots distributed across eight sampling sites along a broad environmental gradient in the Amazon Basin. Plots covered different phytophysiognomies that have a strong relation with forest biomass and, consequently, litter production. We selected six morphological traits related to ant foraging strategies and behavior. Generalized linear mixed models were used to predict how environmental complexity affects trait composition of ground-dwelling ant assemblages. Structurally less complex environments (eg. Amazonian savannah) harboured more species of smaller ants, with relatively smaller mandibles and relatively larger eyes. In more complex environments (eg. dense ombrophylous forest), there were more ant species of larger size, with relatively larger mandibles and relatively smaller eyes. No relationship was detected between relative femur length and the environmental gradient investigated. The functional approach focused on individual traits may illuminate which ant foraging strategies are best adapted to a particular habitat. Our data reveal that the morphological composition of ground-dewelling ant assemblages responds clearly to environmental complexity suggesting that certain ant characteristics offer ecological advantages to particular species in particular habitats. © 2019 Elsevier Masson SA
Don't put all your eggs in one basket – Lessons learned from the largest-scale and longest-term wildlife conservation program in the Amazon Basin
No full textThe Brazilian Government established the Amazon Turtle Project (Projeto Quelônios da Amazônia – PQA) in 1975 to monitor and protect the main nesting sites of Amazon River turtles. The PQA has become the largest-scale and longest-term wildlife conservation initiative in the Brazilian Amazon. We evaluated the outcomes of the PQA across 11 protected localities over 30 years (1977–2008). Inside the protected localities, one population of Podocnemis expansa has declined and four have seen an increase in numbers. The PQA conservation efforts for P. unifilis were not as successful as those of Podocnemis expansa, but were sufficient to stabilize or increase populations. These results suggest that there is a minimum effort necessary for positive conservation outcomes, which was not achieved for Podocnemis sextuberculata. Given the lack of correlation between initial nesting numbers and positive population trends, the current level of success in a given locality cannot be used as a tool to prioritize future protection efforts. We recommend that the PQA should maintain or increase its coverage due to the high levels of local unpredictability. If current harvest trends are maintained, it is likely the only surviving populations of P. expansa will be within protected areas. Considering the scope of the PQA and the period that it has been operational, it is surprising how little recognition it has received; the lack of national and international awareness of its achievements may be one of the main reasons behind the lack of support from the Brazilian Government. © 2019 Elsevier Lt
Contribution to the knowledge of the genus proceratium roger (Hymenoptera: Formicidae: Proceratiinae) in the new world
Get PDFThe genus Proceratium Roger comprises rare ants that are irregularly distributed in tropical and temperate regions of the world. Despite this global distribution, these ants are rarely collected, likely due to their cryptobiotic lifestyle. In the New World, the genus comprises 22 known species distributed from Southern Canada to the South of Brazil, and in some Caribbean islands. The taxonomy of the genus Proceratium is here updated for South America. We describe P. amazonicum sp. nov, from Rondônia state and provide distribution data for P. brasiliense, P. convexipes, and P. silaceum. We also present, for the first time, high-resolution images of the P. colombicum type and P. ecuadoriense, and provide a new record of P. micrommatum from Peru, and comment about its morphological variation and distribution. A key for the workers of the P. micrommatum clade is also provided. The species we describe belongs to P. micrommatum clade and represents the second species recorded from Brazil after 60 years, since only P. brasiliense was known previously in the country. © 2019 Universidade Estadual de Feira de Santana. All rights reserved
Efeito da seleção em laboratório com o biolarvicida Espinosade na fecundidade da população de Aedes aegypti em Manaus, AM
No full textAcordo cooperativo entre a Amazonas Transmissão e Geração de Energia S.A e o INPA
No full textCooperação técnica para a execução do projeto de reintrodução de peixes-bois-da-amazônia sob a guarda da amazonas G
A JAR of Chirps: The Gymnotiform Chirp Can Function as Both a Communication Signal and a Jamming Avoidance Response
Get PDFThe weakly electric gymnotiform fish produce a rhythmic electric organ discharge (EOD) used for communication and active electrolocation. The EOD frequency is entrained to a medullary pacemaker nucleus. During communication and exploration, this rate can be modulated by a pre-pacemaker network, resulting in specific patterns of rate modulation, including stereotyped communication signals and dynamic interactions with conspecifics known as a Jamming Avoidance Response (JAR). One well-known stereotyped signal is the chirp, a brief upward frequency sweep usually lasting less than 500 ms. The abrupt change in frequency has dramatic effects on phase precession between two signalers. We report here on chirping in Brachyhypopmus cf. sullivani, Microsternarchus cf. bilineatus Lineage C, and Steatogenys cf. elegans during conspecific playback experiments. Microsternarchus also exhibits two behaviors that include chirp-like extreme frequency modulations, EOD interruptions with hushing silence and tumultuous rises, and these are described in terms of receiver impact. These behaviors all have substantial impact on interference caused by conspecifics and may be a component of the JAR in some species. Chirps are widely used in electronic communications systems, sonar, and other man-made active sensing systems. The brevity of the chirp, and the phase disruption it causes, makes chirps effective as attention-grabbing or readiness signals. This conforms to the varied assigned functions across gymnotiforms, including pre-combat aggressive or submissive signals or during courtship and mating. The specific behavioral contexts of chirp expression vary across species, but the physical structure of the chirp makes it extremely salient to conspecifics. Chirps may be expected in a wide range of behavioral contexts where their function depends on being noticeable and salient. Further, in pulse gymnotiforms, the chirp is well structured to comprise a robust jamming signal to a conspecific receiver if specifically timed to the receiver’s EOD cycle. Microsternarchus and Steatogenys exploit this feature and include chirps in dynamic jamming avoidance behaviors. This may be an evolutionary re-use of a circuitry for a specific signal in another context. © Copyright © 2019 Field, Petersen, Alves-Gomes and Braun