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This study aimed to evaluate the influence of different anthropic landscape profiles on the diversity and distribution of mosquito species in a rural settlement of the Brazilian Amazon. Eight field collections were conducted at 18 sampling points interspersed throughout 2020-2021. Plastic containers, bamboo internodes, and tires were used as traps to capture immature mosquitoes in three distinct habitats: forest, forest edge, and peridomicile. A total of 15,547 individuals, distributed in 26 species of culicids, were collected. The most abundant species were Culex urichii (8,376 specimens), Culex (Melanoconion) (2,473 specimens), and Aedes albopictus (1,252 specimens). Forest habitat showed the highest abundance, and forest edge showed the highest species richness. Different types of environments influenced both the abundance and richness of mosquitoes. The species composition was also significantly different between the analyzed sites, mainly between forest and peridomicile environments. The change in species dominance could largely explain this change in mosquito community composition. Haemagogus janthinomys, an important sylvatic arbovirus vector, was found in peridomicile habitats and Ae. albopictus, a vector associated with human environments, was found in forest habitats, thus providing evidence of species spillover. Our results indicated that landscape changes affect mosquito communities, influencing their richness and abundance. These changes may have implications for future arboviral outbreaks in this rural settlement due to the possible establishment of sylvatic vector species in anthropic environments.
Assuntos
Aedes , Arbovírus , Culex , Culicidae , Humanos , Animais , Brasil , Mosquitos Vetores , Ecossistema , FlorestasRESUMO
There is often a vertical stratification of the vegetation in tropical forests, where each forest stratum has a unique set of environmental conditions, including marked differences in habitat heterogeneity, physical complexity, and microclimate. Additionally, many tropical forests are highly seasonal, and we need to consider the temporal variation in environmental conditions when assessing the functional aspects of their organisms. Here, we tested the hypothesis that vertical stratification and seasonality shape tropical ants' functional ecology and that there are differences in the functional trait diversity and composition between arboreal and ground-dwelling ant communities. We collected ants in the arboreal and ground strata in the rainy and dry seasons in six different areas, measuring seven morphological traits to characterize their functional ecology and diversity. Irrespective of the season, we found a distinct functional composition between arboreal and ground-dwelling ants and a higher functional richness on the ground. However, ground ants were more functionally redundant than arboreal ants. The differences in functional richness and redundancy between ant inhabiting strata and season could also be observed in the community-weighted mean traits: arboreal and ground ant traits can be distinguished in Weber's length, mandible length, eye length, and eye position on the head capsule. The differences in these functional traits are mainly related to the ants' feeding habits and the complexity of their foraging substrates. Overall, by providing the first systematic comparison of continuous traits between arboreal and ground-dwelling ants, our study opens new investigation paths, indicating important axes of functional diversification of tropical ants.
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Formigas , Árvores , Animais , Clima Tropical , Ecossistema , FlorestasRESUMO
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.
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Biodiversidade , Ecossistema , Brasil , Conservação dos Recursos Naturais , Humanos , ConhecimentoRESUMO
Global initiatives to reforest degraded areas have intensified in recent years, in an attempt to reverse the environmental impacts of habitat loss on species and ecosystem provided by them. However, the effectiveness of such reforestation initiatives in re-establishing biodiversity is still poorly understood. Here, we test how reforestation type and intensity applied to deforested areas affect the reestablishment of communities of cavity-nesting bees and wasps. We deployed experimental trap-nests along a reforestation gradient of increasing structural similarity to primary forest, after 18 years of reforestation. We found that reestablishment, in terms of abundance and richness of both bees and wasps, was greatest at an intermediate point along the reforestation gradient. However, these communities were highly dissimilar to primary forest, and recovery of intact insect community composition was only achieved when reforestation was more similar in structure to natural forests. This effect was more pronounced for bees than for wasps. Our findings suggest that along the reforestation gradient, services provided by wasps will be more easily recovered than those provided by bees. Our results have important implications for the challenges of restoring and maintaining species biodiversity as well as their associated ecosystem services.
Assuntos
Vespas , Animais , Abelhas , Biodiversidade , Brasil , Ecossistema , FlorestasRESUMO
The biodiversity crisis we live in, marked by high extinction rates, requires well-planned conservation efforts. To overcome this issue, red lists of threatened species are recognized as the main objective approach for evaluating the conservation status of species and therefore guiding conservation priorities. This work focuses on the Myriapoda (Chilopoda and Diplopoda) species listed in the Brazilian red list of fauna to enable discussion of the practical implications of red lists for conservation. Almost all myriapods assessed are endemic to Brazil (99 %) and 73 % are known from subterranean habitats only. Despite of 33 % being recorded from protected areas (PAs), downgrading, degazettement or downsizing of PAs and intense and unregulated ecotourism represent great threats. The PAs network in Brazil tends to fail in conserving myriapod species. The number of data deficient species (42 %) states the need of investing in ecological and taxonomic studies about the group, in order to fill in important knowledge gaps in species assessments nationally and globally. In this work we show that there is a lack of communication between national and global agencies concerning red lists, which results in a significant loss for science and for conservation. Despite investing in national and state red lists, individual countries must take the final step of submitting its data to IUCN global database, as significant international funding is available for IUCN red listed species conservation. Being one of the most diverse countries in the world, and facing the biggest cuts ever on national science funding, losing these important funding opportunities is a huge loss for Brazilian biodiversity conservation and for science. This study raises awareness on subterranean habitats conservation, due to its high endemism and fragility. Since the first edition of the Brazilian Red List in 1968, centipedes are now included for the first time, and millipedes for the second time. The presence of these myriapods in the list brings attention to the group, which usually receives little or no attention in conservation programs and environmental impact assessments. Rather than a specific case for Myriapoda and for Brazil, the points discussed here can be related to arthropods and the tropics, as the most biodiverse countries are emerging economies facing similar challenges in PAs network management, species extinction risks and science funding.
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Abstract Fire management is an important issue in the Brazilian Cerrado, since both anthropogenic high intensity fires and complete fire suppression can reduce the biodiversity in this biome. In this paper, we highlight the trends in scientific literature about fire effects in the Cerrado, aiming to detect possible gaps and to indicate directions of future scientific research. We searched for articles in the periodic database Web of Knowledge from 1991 to 2016, and observed an increase in the number of publications throughout the years. Most articles were associated with Brazilian institutions (58%), followed by those with collaboration between Brazilian and international institutions (33%), and those published by authors exclusively from international institutions (9%). Most articles addressed the effects of fire on biodiversity (77%), followed by articles about abiotic environment (19%), and then biotic interactions or interactions between organisms and environment (4%). The most studied taxonomic group was plants (75%), followed by mammals (8%) and insects (6%), with the remaining taxa comprising about 11% of publications. The Federal District was the federative unit with the greatest number of studies (31%). The majority of studies was conducted in areas with fewer fire events, whereas areas with major incidence of fires are poorly studied. Our data shows that studies on the effect of fires on the Brazilian Cerrado are geographically and taxonomically biased. This lack of knowledge limits the extrapolations about the effects of fire on this biome. Therefore, we emphasize the need for investment in research in areas with high fire frequency and also for an increase in knowledge about these effects on the biota, especially on the fauna. This action is fundamental to support the development of public policies for effective and directed fire management in the Cerrado.
Resumo O manejo do fogo é uma questão importante no Cerrado brasileiro, pois tanto os incêndios antropogênicos de alta intensidade, quanto a sua supressão completa podem reduzir a biodiversidade neste bioma. Neste artigo, destacamos as tendências na literatura científica sobre os efeitos do fogo no Cerrado, com o objetivo de detectar possíveis lacunas e indicar direções de futuras pesquisas científicas. Buscamos artigos na base de periódicos Web of Knowledge no período de 1991 a 2016, e observamos um aumento no número de publicações ao longo dos anos. A maioria dos artigos foi associada a instituições brasileiras (58%), seguidos por colaborações entre instituições brasileiras e internacionais (33%) e publicações de autores exclusivamente de instituições internacionais (9%). A maioria dos artigos abordou os efeitos do fogo na biodiversidade (77%), seguido de artigos sobre o ambiente abiótico (19%), e interações bióticas ou interações entre organismos e o ambiente (4%). O grupo taxonômico mais estudado foi plantas (75%), seguido de mamíferos (8%) e insetos (6%). Os táxons restantes incluem 11% das publicações. O Distrito Federal foi a unidade federativa com o maior número de estudos (31%). A maioria dos estudos foi realizada em áreas com menos queimadas, enquanto as áreas com maior incidência de fogo são mal estudadas. Nossos dados mostram que os estudos sobre o efeito do fogo no Cerrado brasileiro são enviesados do ponto de vista geográfico e taxonômico. Esta falta de conhecimento limita as extrapolações sobre o efeito do fogo neste bioma. Portanto, enfatizamos a necessidade de investimentos para pesquisas em áreas com alta freqüência de queimadas e a necessidade em aumentar o conhecimento sobre estes efeitos na biota, especialmente na fauna. Esta ação é fundamental para apoiar o desenvolvimento de políticas públicas para uma gestão efetiva e direcionada do fogo no Cerrado.
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Os benefícios obtidos por um organismo em uma associação mutualística podem variar em função de fatores ambientais, bem como entre as diferentes espécies que podem estar associadas. Neste trabalho demonstramos que quatro espécies de formigas, Crematogaster brasiliensis, Allomerus octoarticulatus e duas não identificadas do gênero Azteca podem ser encontradas associadas à mirmecófita Cordia nodosa em florestas ripárias sul-amazônicas. Essa composição de espécies de formigas é mais similar a encontrada na Amazônia Andina do que aquela da Amazônia Central brasileira. A colonização por formigas parece ser determinante, pois diminuiu a herbivoria e, consequentemente, aumentou a probabilidade de C. nodosa produzir frutos. Adicionalmente, mesmo não havendo diferença na herbivoria entre plantas colonizadas pelas diferentes espécies de formigas, a probabilidade de uma planta colonizada por formigas do gênero Allomerus produzir frutos é menor do que quando colonizadas pelas outras espécies de formigas. Esse estudo demonstra a dependência de C. nodosa pela colonização de formigas para sua reprodução. Contudo, conforme outros estudos realizados em outras áreas da Amazônia demonstram, nossos resultados também sugerem que Allomerus pode estar castrando as plantas hospedeiras, agindo como parasita em toda a sua distribuição geográfica.
The benefits obtained by an organism when involved in a mutualistic interaction vary depending on environmental factors, as well as among the identity of the involved species. In this study, we showed that four ant species, Crematogaster brasiliensis, Allomerus octoarticulatus, and two unidentified Azteca species can be found associated to the myrmecophite Cordia nodosa in riparian forests in the South of Amazonia. This composition of ant-associated species is more similar in forests of Andean Amazon than in Central Amazonia. The colonization of an ant colony on C. nodosa seems to be vital in order to decrease herbivory, as increased the probability of a plant sets fruits. Moreover, even though we did not find significant differences in herbivory among plants colonized by different ant species, the probability of a plant produces fruits is much lower when it is colonized by Allomerus ants. Overall, this study shows that C. nodosa depends on ants to reproduce. However, based on other empirical studies across the Amazon, our results also suggest that Allomerus ants can act as flower castrator, acting as a parasite over its geographic range.
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Animais , Formigas , Simbiose , Eutérios , CordiaRESUMO
This study was undertaken to investigate the prevalence of Mansonella ozzardi infection and to estimate the parasitic infection rate (PIR) in simuliid black flies in the municipality of Pauini, Amazonas, Brazil. We used thick blood films to examine 921 individuals in 35 riverine communities along the Pauini and Purus Rivers. Simuliids were caught in several communities. Flies were identified, stained with haematoxylin and dissected. Overall, 44 (24.86%) of 177 riverines were infected in communities on the Pauini River and 183 (24.19%) of 744 on the Purus. The prevalence was higher in men (31.81% and 29.82%) than in women (17.98% and 19.18%) and occurred in most age groups. The prevalence increased sharply in the 28-37 (50% and 42.68%) age group and increased in the older age classes. The highest prevalence was in farmers (44% and 52.17%, respectively) in the Pauini and Purus Rivers. Only Cerqueirellum amazonicum (Simuliidae) transmits M. ozzardi in this municipality, and we found a PIR of 0-8.43% and infectivity rate of 0-3.61%. These results confirm that rates of M. ozzardi infection are high in Pauini and suggest that its prevalence may be far greater than has been previously reported due to the absence of a program for treating the population.
Assuntos
Insetos Vetores/parasitologia , Mansonella/isolamento & purificação , Mansonelose/epidemiologia , Simuliidae/parasitologia , Adolescente , Adulto , Idoso , Animais , Brasil/epidemiologia , Criança , Pré-Escolar , Feminino , Humanos , Insetos Vetores/classificação , Masculino , Mansonelose/diagnóstico , Pessoa de Meia-Idade , Prevalência , Simuliidae/classificação , Adulto JovemRESUMO
This study was undertaken to investigate the prevalence of Mansonella ozzardi infection and to estimate the parasitic infection rate (PIR) in simuliid black flies in the municipality of Pauini, Amazonas, Brazil. We used thick blood films to examine 921 individuals in 35 riverine communities along the Pauini and Purus Rivers. Simuliids were caught in several communities. Flies were identified, stained with haematoxylin and dissected. Overall, 44 (24.86 percent) of 177 riverines were infected in communities on the Pauini River and 183 (24.19 percent) of 744 on the Purus. The prevalence was higher in men (31.81 percent and 29.82 percent) than in women (17.98 percent and 19.18 percent) and occurred in most age groups. The prevalence increased sharply in the 28-37 (50 percent and 42.68 percent) age group and increased in the older age classes. The highest prevalence was in farmers (44 percent and 52.17 percent, respectively) in the Pauini and Purus Rivers. Only Cerqueirellum amazonicum (Simuliidae) transmits M. ozzardi in this municipality, and we found a PIR of 0-8.43 percent and infectivity rate of 0-3.61 percent. These results confirm that rates of M. ozzardi infection are high in Pauini and suggest that its prevalence may be far greater than has been previously reported due to the absence of a program for treating the population.
Assuntos
Adolescente , Adulto , Idoso , Animais , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Insetos Vetores/parasitologia , Mansonella/isolamento & purificação , Mansonelose/epidemiologia , Simuliidae/parasitologia , Brasil/epidemiologia , Insetos Vetores/classificação , Mansonelose/diagnóstico , Prevalência , Simuliidae/classificação , Adulto JovemRESUMO
We studied the influence of climatic parameters in the daily haematophagic activity of Cerqueirellum argentiscutum from September/1999 to August/2000. The bite activity observed was different according to the annual rain precipitation (dry and rainy seasons). Humidity and temperature were the factors that most influenced it in both periods. During the dry season, it was greater in the beginning of the morning, showing a positive association with the humidity. However, during the rainy season, it was negatively related to that same factor. When wind speed was higher than 10 Km.h-1, it was reduced abruptly. Light intensity, atmospheric pressure and cloudiness seemed to act as secondary factors in the daily abundance of C. argentiscutum.
Foi estudada a influência dos parâmetros climáticos na atividade hematofágica diária de Cerqueirellum argentiscutum durante setembro/1999 a agosto/2000. Foi observado que a atividade foi diferente conforme as estações (seca e chuvosa). A umidade e a temperatura foram os fatores que mais influenciaram na atividade em ambas as estações. Na estação seca foi maior no início da manhã apresentando uma associação positiva com a umidade. Porém na estação chuvosa se mostrou negativamente relacionada com este mesmo fator. Quando a velocidade do vento foi superior a 10 Km.h-1 diminuiu bruscamente. A luminosidade, pressão atmosférica e nebulosidade parecem atuar como fatores secundários na abundância diária de C. argentiscutum.