12 research outputs found

    Cobertura de líquens em um gradiente borda-interior na Amazônia Central

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    Nas florestas tropicais, o efeito de borda é considerado um dos fatores que afetam o equilíbrio do ecossistema. Como consequência desse distúrbio, inúmeros grupos de organismos têm suas populações afetadas. Os líquens são particularmente sensíveis às mudanças microclimáticas, pois retiram nutrientes diretamente da atmosfera e apresentam pequena capacidade de regulação de perda e ganho de água. Eles são classificados quanto às formas e o crescimento. O objetivo deste trabalho foi testar se líquens com diferentes características morfo-anatômicas apresentam tolerância distinta às condições de borda florestal. A hipótese testada é de que líquens com características morfo-anatômicas que minimizem a perda de água são menos susceptíveis ao efeito de borda. Nas árvores amostradas foram amostrados 389 pontos com líquens do tipo “A” (líquens crostosos com córtex liso e sem protalos) e 123 com líquens do tipo B (líquens hidrófilos, sem córtex definido, que retêm água nos protalos). Embora não tenha havido relação entre a distância de borda e a cobertura dos liquens do tipo “A”, a cobertura relativa dos líquens do tipo B diminuiu com o aumento da distância da borda. Houve relação negativa entre a distância da borda e a temperatura ao meio dia e foi encontrada uma relação entre a distância da borda e a umidade relativa do ar. Nos 10 primeiros metros de distância da borda os líquens do tipo B apresentaram uma maior cobertura relativa, já nas distâncias subsequentes houve uma inversão, onde os líquens do tipo A passaram a ter maior cobertura relativa

    New records of host plants used by a weaver ants Camponotus textor Forel, 1899 (Hymenoptera: Formicidae)

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    Weaver ants nest on plants but the extent of such associations is unknown for many species. Literature records of weaver ant host plants from 1945 to 2016 showed that Camponotus textor Forel, 1899 (= Camponotus senex), the brazilian savanna weaver ant, was recorded on 17 plant species belonging to 11 families. Our field survey recorded nine plant species in eight families at Brazilian Cerrado. Overall, we expanded the list to a total of 24 host plant species and 14 families, including economically important tree species as mango, citrus and jambo trees. Such host plants could be used to augment establishment of weaver ants, facilitating their role in biocontrol as deterrents of phytophagous insect pests of economically important plants

    Pervasive gaps in Amazonian ecological research

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    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

    Pervasive gaps in Amazonian ecological research

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    Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences

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    The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & Nemésio 2007; Donegan 2008, 2009; Nemésio 2009a–b; Dubois 2009; Gentile & Snell 2009; Minelli 2009; Cianferoni & Bartolozzi 2016; Amorim et al. 2016). This question was again raised in a letter supported by 35 signatories published in the journal Nature (Pape et al. 2016) on 15 September 2016. On 25 September 2016, the following rebuttal (strictly limited to 300 words as per the editorial rules of Nature) was submitted to Nature, which on 18 October 2016 refused to publish it. As we think this problem is a very important one for zoological taxonomy, this text is published here exactly as submitted to Nature, followed by the list of the 493 taxonomists and collection-based researchers who signed it in the short time span from 20 September to 6 October 2016

    Pervasive gaps in Amazonian ecological research

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    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

    Ant diversity (Hymenoptera: Formicidae) in natural regeneration areas of Cerrado

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    Os bioindicadores são organismos ou comunidades de organismos que apresentam respostas às mudanças do ecossistema, servindo como guia da condição ambiental como um todo. Dentre estas mudanças se destacam as resultantes de ações antrópicas que, no Cerrado, foram responsáveis pela redução da área nativa à metade do valor original. As formigas têm sido utilizadas como bioindicadores em programas de monitoramento de ecossistemas por compartilharem características de alto valor na bioindicação. O presente trabalho buscou o levantamento da diversidade de formigas e identificação de espécies indicadoras em duas áreas com diferentes níveis de regeneração de Cerrado: nível de regeneração inicial e avançado. Objetivou-se testar o pressuposto de que a diversidade de formigas responde ao gradiente de regeneração do Cerrado, apresentando um aumento na diversidade quanto maior for nível de regeneração da área. Adicionalmente, buscou-se avaliar a riqueza e composição de espécies de formigas através das seguintes hipóteses: (1) a riqueza de formigas aumenta sob influência do nível de regeneração mais avançada, possivelmente em decorrência do aumento da diversidade vegetal e de nichos disponíveis; que (2) há uma separação na composição taxonômica e de guildas nas áreas regeneração; e (3) que a riqueza e abundância das guildas, da mesma forma, aumentam sob influência do nível de regeneração das áreas. Para a execução deste trabalho foi realizada uma coleta no início da estação seca as áreas de reserva da fazenda Nova Monte Carmelo, Minas Gerais, Brasil. Foram estabelecidas 16 parcelas em cada nível de regeneração nas quais foram distribuídos um total de 128 pitfalls epigéicos. No total, foram coletadas 87 espécies/morfospécies de formigas sendo 64 em regeneração inicial e 71 em regeneração avançada sendo que 55,17% das espécies foram encontradas nas duas áreas. Os gêneros mais abundantes coletados foram Pheidole, Solenopsis e Camponotus. As áreas de regeneração avançada apresentaram maior riqueza que a área de regeneração inicial. Foram encontradas diferentes espécies indicadoras em cada área sendo em regeneração inicial: Solenopsis sp. e Dorymyrmex sp., e em regeneração avançada: Atta sp., Camponotus crassus, C. personatus, C. sp. E, Ectatomma permagnum, Pheidole sp., Pheidole sp., Pseudomyrmex termitarius e Pogonomyrmex naegelli. A análise de composição taxonômica resultou na formação de dois grupos distintos sugerindo que a regeneração dirige a separação taxonômica. Por outro lado, a composição taxonômica de guildas não apresentou distinção estatística clara entre as áreas. As áreas de regeneração avançada apresentaram representantes de todas as nove guildas coletadas, enquanto as áreas de regeneração inicial obtiveram apenas oito. Além disso, houve diferença entre as proporções de guildas entre as áreas. Desta forma, excetuando-se a composição de guildas, as demais hipóteses aqui testadas foram corroboradas concordando assim com o pressuposto do trabalho. O presente trabalho reafirma a eficiência destes componentes em análises comparativas de áreas de regeneração do Cerrado, apresentando respostas visíveis e eficientes em todos os componentes de comunidades aqui analisadosBioindicators are organisms or communities of organisms that respond to ecosystem changes, serving as a guide to the overall environmental condition. Among these changes are those resulting from anthropic actions that, in the Cerrado, were responsible for reducing the native area to half the original value. Ants have been used as bioindicators in ecosystem monitoring programs because they share characteristics of high value in bioindication. The present work sought to survey the diversity of ants and identification of indicator species in two areas with different regeneration level of Cerrado: initial and advanced regeneration levels. The objective was to test the assumption that the response of ant diversity to the regeneration gradient varies according to the regeneration level of each area. In addition, we aimed to evaluate the richness and composition of ant species through the following hypotheses: (1) ant richness increases under the influence of the more advanced regeneration level, possibly due to the increase of plant diversity and available niches; That (2) there is a separation in the taxonomic composition and of guilds in the regeneration areas; And (3) that the wealth and abundance of the guilds likewise increase under the influence of the level of regeneration of the areas. For the execution of this work a collection was carried out at the beginning of the dry season the reserve areas of Nova Monte Carmelo farm, Minas Gerais, Brazil. Sixteen plots were established at each regeneration level in which a total of 128 epigene pitfalls were distributed. In total, 87 species / morphs of ants were collected, 64 in initial regeneration and 71 in advanced regeneration, and 55.17% of the species were found in both areas. The most abundant genera collected were Pheidole, Solenopsis and Camponotus. The areas of advanced regeneration presented greater wealth than the initial regeneration area. Different indicator species were found in each area and in initial regeneration: Solenopsis sp. And Dorymyrmex sp., And in advanced regeneration: Atta sp., Camponotus crassus, C. personatus, C. sp. E, Ectatomma permagnum, Pheidole sp., Pheidole sp., Pseudomyrmex termitarius and Pogonomyrmex naegelli. The analysis of taxonomic composition resulted in the formation of two distinct groups suggesting that regeneration drives the taxonomic separation. On the other hand, the taxonomic composition of guilds did not present a clear statistical distinction between the areas. The areas of advanced regeneration presented representatives of all nine guilds collected, while the areas of initial regeneration obtained only eight. In addition, there was a difference between the proportions of guilds between the areas. Thus, with the exception of guild composition, the other hypotheses tested here were corroborated, thus agreeing with the assumption of the work. The present work reaffirms the efficiency of these components in comparative analyzes of Cerrado regeneration areas, presenting visible and efficient responses in all components of communities analyzed her

    NEOTROPICAL XENARTHRANS: a data set of occurrence of xenarthran species in the Neotropics

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    Xenarthrans—anteaters, sloths, and armadillos—have essential functions for ecosystem maintenance, such as insect control and nutrient cycling, playing key roles as ecosystem engineers. Because of habitat loss and fragmentation, hunting pressure, and conflicts with domestic dogs, these species have been threatened locally, regionally, or even across their full distribution ranges. The Neotropics harbor 21 species of armadillos, 10 anteaters, and 6 sloths. Our data set includes the families Chlamyphoridae (13), Dasypodidae (7), Myrmecophagidae (3), Bradypodidae (4), and Megalonychidae (2). We have no occurrence data on Dasypus pilosus (Dasypodidae). Regarding Cyclopedidae, until recently, only one species was recognized, but new genetic studies have revealed that the group is represented by seven species. In this data paper, we compiled a total of 42,528 records of 31 species, represented by occurrence and quantitative data, totaling 24,847 unique georeferenced records. The geographic range is from the southern United States, Mexico, and Caribbean countries at the northern portion of the Neotropics, to the austral distribution in Argentina, Paraguay, Chile, and Uruguay. Regarding anteaters, Myrmecophaga tridactyla has the most records (n = 5,941), and Cyclopes sp. have the fewest (n = 240). The armadillo species with the most data is Dasypus novemcinctus (n = 11,588), and the fewest data are recorded for Calyptophractus retusus (n = 33). With regard to sloth species, Bradypus variegatus has the most records (n = 962), and Bradypus pygmaeus has the fewest (n = 12). Our main objective with Neotropical Xenarthrans is to make occurrence and quantitative data available to facilitate more ecological research, particularly if we integrate the xenarthran data with other data sets of Neotropical Series that will become available very soon (i.e., Neotropical Carnivores, Neotropical Invasive Mammals, and Neotropical Hunters and Dogs). Therefore, studies on trophic cascades, hunting pressure, habitat loss, fragmentation effects, species invasion, and climate change effects will be possible with the Neotropical Xenarthrans data set. Please cite this data paper when using its data in publications. We also request that researchers and teachers inform us of how they are using these data

    NEOTROPICAL ALIEN MAMMALS: a data set of occurrence and abundance of alien mammals in the Neotropics

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    Biological invasion is one of the main threats to native biodiversity. For a species to become invasive, it must be voluntarily or involuntarily introduced by humans into a nonnative habitat. Mammals were among first taxa to be introduced worldwide for game, meat, and labor, yet the number of species introduced in the Neotropics remains unknown. In this data set, we make available occurrence and abundance data on mammal species that (1) transposed a geographical barrier and (2) were voluntarily or involuntarily introduced by humans into the Neotropics. Our data set is composed of 73,738 historical and current georeferenced records on alien mammal species of which around 96% correspond to occurrence data on 77 species belonging to eight orders and 26 families. Data cover 26 continental countries in the Neotropics, ranging from Mexico and its frontier regions (southern Florida and coastal-central Florida in the southeast United States) to Argentina, Paraguay, Chile, and Uruguay, and the 13 countries of Caribbean islands. Our data set also includes neotropical species (e.g., Callithrix sp., Myocastor coypus, Nasua nasua) considered alien in particular areas of Neotropics. The most numerous species in terms of records are from Bos sp. (n = 37,782), Sus scrofa (n = 6,730), and Canis familiaris (n = 10,084); 17 species were represented by only one record (e.g., Syncerus caffer, Cervus timorensis, Cervus unicolor, Canis latrans). Primates have the highest number of species in the data set (n = 20 species), partly because of uncertainties regarding taxonomic identification of the genera Callithrix, which includes the species Callithrix aurita, Callithrix flaviceps, Callithrix geoffroyi, Callithrix jacchus, Callithrix kuhlii, Callithrix penicillata, and their hybrids. This unique data set will be a valuable source of information on invasion risk assessments, biodiversity redistribution and conservation-related research. There are no copyright restrictions. Please cite this data paper when using the data in publications. We also request that researchers and teachers inform us on how they are using the data
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