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1.
An Acad Bras Cienc ; 95(3): e20230051, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37878914

RESUMO

Long-term-ecological-research (LTER) faces many challenges, including the difficulty of obtaining long-term funding, changes in research questions and sampling designs, keeping researchers collecting standardized data for many years, impediments to interactions with local people, and the difficulty of integrating the needs of local decision makers with "big science". These issues result in a lack of universally accepted guidelines as to how research should be done and integrated among LTER sites. Here we discuss how the RAPELD (standardized field infrastructure system), can help deal with these issues as a complementary technique in LTER studies, allowing comparisons across landscapes and ecosystems and reducing sampling costs. RAPELD uses local surveys to understand broad spatial and temporal patterns while enhancing decision-making and training of researchers, local indigenous groups and traditional communities. Sampling of ecological data can be carried out by different researchers through standardized protocols, resulting in spatial data that can be used to answer temporal questions, and allow new questions to be investigated. Results can also be integrated into existing biodiversity networks. Integrated systems are the most efficient way to save resources, maximize results, and accumulate information that can be used in the face of the unknown unknowns upon which our future depends.


Assuntos
Biodiversidade , Ecossistema , Humanos , Estudos Longitudinais
2.
An Acad Bras Cienc ; 93(2): e20201604, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33852672

RESUMO

The Program for Biodiversity Research (PPBio) is an innovative program designed to integrate all biodiversity research stakeholders. Operating since 2004, it has installed long-term ecological research sites throughout Brazil and its logic has been applied in some other southern-hemisphere countries. The program supports all aspects of research necessary to understand biodiversity and the processes that affect it. There are presently 161 sampling sites (see some of them at Supplementary Appendix), most of which use a standardized methodology that allows comparisons across biomes and through time. To date, there are about 1200 publications associated with PPBio that cover topics ranging from natural history to genetics and species distributions. Most of the field data and metadata are available through PPBio web sites or DataONE. Metadata is available for researchers that intend to explore the different faces of Brazilian biodiversity spatio-temporal variation, as well as for managers intending to improve conservation strategies. The Program also fostered, directly and indirectly, local technical capacity building, and supported the training of hundreds of undergraduate and graduate students. The main challenge is maintaining the long-term funding necessary to understand biodiversity patterns and processes under pressure from global environmental changes.


Assuntos
Biodiversidade , Ecossistema , Brasil , Conservação dos Recursos Naturais , Humanos , Conhecimento
3.
PeerJ ; 11: e15393, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37250715

RESUMO

Background: The delimitation of cryptic species is a challenge for biodiversity conservation. Anurans show high cryptic diversity levels, and molecular species delimitation methods could help identify putative new species. Additionally, species delimitation approaches can provide important results for cryptic species conservation, with integrative methods adding robustness to results. Ischnocnema manezinho was described from Santa Catarina Island (SCI), southern Brazil. More recently, some inventories indicated continental populations supposedly similar in morphology to it. If these records are confirmed as I. manezinho, it would likely change its endangered status on National Red List, removing the species from conservation agendas. We investigated the threatened frog Ischnocnema manezinho, to evaluate if the continental populations belong to this species or if they form an undescribed species complex. Methods: We used coalescent, distance, and allele-sharing-based species delimitation methods and integrative analyses of morphometric and bioacoustics traits to test evolutionary independence between I. manezinho from SCI, Arvoredo Island, and continental populations. Results: Ischnocnema manezinho is restricted to Santa Catarina Island, while the five remaining lineages should be further investigated through a taxonomic review. Our results point to a small geographic range of Ischnocnema manezinho. Additionally, the species occurs in isolated fragments of forest in SCI surrounded by expanding urban areas, confirming its status as Endangered. Thus, the protection and monitoring of I. manezinho and the taxonomic description of the continental and Arvoredo Island candidate species should be priorities.


Assuntos
Anuros , Florestas , Animais , Filogenia , Anuros/genética , Biodiversidade , Folhas de Planta
4.
Sci Data ; 10(1): 771, 2023 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-37932332

RESUMO

Global change is predicted to induce shifts in anuran acoustic behavior, which can be studied through passive acoustic monitoring (PAM). Understanding changes in calling behavior requires automatic identification of anuran species, which is challenging due to the particular characteristics of neotropical soundscapes. In this paper, we introduce a large-scale multi-species dataset of anuran amphibians calls recorded by PAM, that comprises 27 hours of expert annotations for 42 different species from two Brazilian biomes. We provide open access to the dataset, including the raw recordings, experimental setup code, and a benchmark with a baseline model of the fine-grained categorization problem. Additionally, we highlight the challenges of the dataset to encourage machine learning researchers to solve the problem of anuran call identification towards conservation policy. All our experiments and resources have been made available at https://soundclim.github.io/anuraweb/ .


Assuntos
Anuros , Vocalização Animal , Animais , Acústica , Ecossistema
5.
Ecology ; 100(12): e02861, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31380568

RESUMO

Habitat destruction is the single greatest anthropogenic threat to biodiversity. Decades of research on this issue have led to the accumulation of hundreds of data sets comparing species assemblages in larger, intact, habitats to smaller, more fragmented, habitats. Despite this, little synthesis or consensus has been achieved, primarily because of non-standardized sampling methodology and analyses of notoriously scale-dependent response variables (i.e., species richness). To be able to compare and contrast the results of habitat fragmentation on species' assemblages, it is necessary to have the underlying data on species abundances and sampling intensity, so that standardization can be achieved. To accomplish this, we systematically searched the literature for studies where abundances of species in assemblages (of any taxa) were sampled from many habitat patches that varied in size. From these, we extracted data from several studies, and contacted authors of studies where appropriate data were collected but not published, giving us 117 studies that compared species assemblages among habitat fragments that varied in area. Less than one-half (41) of studies came from tropical forests of Central and South America, but there were many studies from temperate forests and grasslands from all continents except Antarctica. Fifty-four of the studies were on invertebrates (mostly insects), but there were several studies on plants (15), birds (16), mammals (19), and reptiles and amphibians (13). We also collected qualitative information on the length of time since fragmentation. With data on total and relative abundances (and identities) of species, sampling effort, and affiliated meta-data about the study sites, these data can be used to more definitively test hypotheses about the role of habitat fragmentation in altering patterns of biodiversity. There are no copyright restrictions. Please cite this data paper and the associated Dryad data set if the data are used in publications.

6.
Mitochondrial DNA A DNA Mapp Seq Anal ; 27(6): 4270-4273, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27206788

RESUMO

This study presents evidence of concerted evolution in the mitochondrial control region of the frog Pseudopaludicola canga. Four repeat units of 88 bp (as well as a fifth, incomplete unit) were observed in the 5' domain, with the duplicated segments of the same specimen being more related to one another than to the equivalent regions in other specimens, as a result of concerted evolution. We highlight that drawing conclusions from phylogeographical analysis using the control region containing VNTRs must be interpreted with caution, because it violated a basic assumption of phylogeny, since the regions cannot be treated as independent characters.


Assuntos
Anuros/genética , DNA Mitocondrial/genética , Genoma Mitocondrial/genética , Mitocôndrias/genética , Animais , Sequência de Bases , Filogenia
7.
Zootaxa ; 3881(4): 341-61, 2014 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-25543640

RESUMO

We describe Dendropsophus ozzyi sp. nov., a new species of treefrog, tentatively included in the Dendropsophus microcephalus Group and most notably diagnosed by the presence of pointed fingers and an advertisement call with a very high dominant frequency. The new species is known from three localities in the Brazilian Amazon forest, two on western State of Pará and one (the type locality) in eastern State of Amazonas (03°56'50"S and 58°26'36"W, 45 m a.s.l.).


Assuntos
Anuros/anatomia & histologia , Anuros/classificação , Vocalização Animal , Distribuição Animal , Animais , Anuros/fisiologia , Brasil , Ecossistema , Feminino , Masculino , Comportamento Sexual Animal , Especificidade da Espécie
8.
Acta amaz ; 42(2): 221-226, June 2012. ilus, tab
Artigo em Inglês | LILACS | ID: lil-616883

RESUMO

Construction of hydroelectric dams in tropical regions has been contributing significantly to forest fragmentation. Alterations at edges of forest fragments impact plant communities that suffer increases in tree damage and dead, and decreases in seedling recruitment. This study aimed to test the core-area model in a fragmented landscape caused by construction of a hydroelectric power plant in the Brazilian Amazon. We studied variations in forest structure between the margin and interiors of 17 islands of 8-100 hectares in the Tucuruí dam reservoir, in two plots (30 and >100m from the margin) per island. Mean tree density, basal area, seedling density and forest cover did not significantly differ between marginal and interior island plots. Also, no significant differences were found in liana density, dead tree or damage for margin and interior plots. The peculiar topographic conditions associated with the matrix habitat and shapes of the island seem to extend edge effects to the islands' centers independently of the island size, giving the interior similar physical microclimatic conditions as at the edges. We propose a protocol for assessing the ecological impacts of edge effects in fragments of natural habitat surrounded by induced (artificial) edges. The protocol involves three steps: (1) identification of focal taxa of particular conservation or management interest, (2) measurement of an "edge function" that describes the response of these taxa to induced edges, and (3) use of a "Core-Area Model" to extrapolate edge function parameters to existing or novel situations.


A construção de usinas hidrelétricas em regiões tropicais tem contribuído significativamente para a fragmentação da floresta. As alterações nas bordas de fragmentos florestais causam profundos impactos na comunidade de plantas, tais como, o aumento em de árvores mortas ou danificadas e a diminuição do recrutamento de plântulas. Este estudo tem como objetivo testar o modelo de área nuclear (core-area model) em uma paisagem de floresta fragmentada resultante da formação do lago da Usina Hidrelétrica de Tucucui na Amazônia. Foram medidas as variações na estrutura em 17 ilhas, com tamanhos variando de 8 a 100 hectares. Em cada ilha foram colocadas duas parcelas, a 1ª parcela a 30 metros da margem e a 2ª parcela a mais de 100 metros da margem da ilha. A densidade e a área basal de árvores, a densidade da regeneração natural e a cobertura do dossel da floresta não foram significativamente diferentes entre as parcelas da borda e do interior das ilhas. Também não foram encontradas diferenças significativas na densidade de lianas, no número de troncos mortos ou árvores danificadas entre as parcelas da borda e do interior das ilhas. A grande declividade do terreno das ilhas, a matriz circundante (água) e a forma irregular da ilhas podem ser os fatores responsáveis me provocar a extensão do efeito de borda em todas as ilhas analisadas, independente do tamanho e grau de isolamento. Nós propomos um novo protocolo para avaliar os impactos ecológicos dos efeitos de borda em fragmentos de habitat criados artificialmente. Este protocolo envolve três etapas: (1) identificação dos táxons biológicos de particular interesse de conservação ou de gestão (2) medição das das variáveis responsaveis pela resposta dos táxons induzidas pelo efeito de borda e (3) Usar o modelo de área nuclear (core area model) na extrapolação das variáveis medidas em situacões novas ou existentes.


Assuntos
Centrais Hidrelétricas
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