Communities ecology of medium and large size mammals in the state of Tocantins, Brazil

Doutoramento em Biologia e Ecologia das Alterações GlobaisO bioma Cerrado, representado pelos vários tipos fisionômicos de vegetação que o termo encerra em seu sentido genérico, ocupa uma área de aproximadamente 90% do território do estado do Tocantins. Esse importante hotspot vem sendo progressivamente ocupado por empreendimentos de desenvolvimento, provocando a rápida modificação da paisagem. Os impactos dessa ocupação implicam em perda de habitats, com a consequente redução das espécies da fauna, particularmente das espécies de mamíferos de médio e grande porte cuja maior demanda energética implica em menores densidades, maiores áreas de vida e uma maior probabilidade de extinção. Para o bioma Cerrado do estado do Tocantins, os estudos sobre a ecologia de comunidades de mamíferos de médio e grande porte são escassos e pontuais. Diante desse contexto de desconhecimento, o objetivo deste estudo foi avaliar aspectos da ecologia das comunidades de mamíferos de médio e grande porte, como riqueza, similaridade na utilização do habitat, distância geográfica na similaridade das espécies e períodos de atividade. As informações apresentadas neste estudo, são resultados de onze anos de trabalhos de levantamento, monitoramento e resgate da fauna de mamíferos de médio e grande porte, realizados em empreendimentos de desenvolvimento estabelecidos no bioma Cerrado do estado do Tocantins. Foram registradas 47 espécies de mamíferos de médio e grande porte, representando 92,1% das espécies registradas para todo o bioma Cerrado. Quatorze espécies encontram-se relacionadas como ameaçadas de extinção. A riqueza estimada pelo estimador não paramétrico Jackknife primeira ordem foi superior à riqueza observada, em todos os tipos fisionômicos de vegetação estudados, porém a eficiência amostral foi considerada alta, com média de 74,9%. Os registros de Aotus infulatus, Leopardus braccatus, Potos flavus, Sylvilagus brasiliensis e Dasyprocta prymnolopha foram novos e ampliaram a área de distribuição dessas espécies. Os resultados obtidos para a classificação aglomerativa de Dajoz, para os índices de similaridade de Jaccard e para as análises de agrupamento e de componentes principais permitiram inferir uma distribuição diferenciada das espécies de mamíferos de médio e grande porte em relação à utilização do habitat. As espécies registradas utilizam todos os tipos fisionômicos de vegetação da área de estudo, porém com uma distribuição disjunta de espécies, em relação aos mesmos. Em 80% das análises de regressão realizadas, não foi detectada a influência da distância geográfica sobre a similaridade em espécies não permitindo, portanto, inferências sobre distribuições geográficas diferenciadas das espécies de mamíferos de médio e grande porte. As espécies de mamíferos de médio e grande porte, cujos registros fotográficos permitiram a determinação de períodos de atividade, mostraram comportamentos diurnos, predominantemente diurnos, noturnos, predominantemente noturnos e catemerais. A elevada riqueza em espécies de mamíferos de médio e grande porte, suas estreitas dependências e associações com os tipos fisionômicos de vegetação, a presença de espécies ameaçadas de extinção e a fragilidade dessa comunidade ecológica frente às alterações crescentes em seus habitats, tornam urgente a adoção de políticas públicas de criação de unidades de conservação para proteger essas e outras espécies do bioma Cerrado do estado do Tocantins.The Cerrado biome, represented by the various vegetation types that the term ends in its generic sense, occupies an area of approximately 90% of the Tocantins state territory. This important hotspot has been progressively occupied by development enterprises, causing rapid change in the landscape. The impacts of this occupation involves habitat loss, with the consequent reduction of wildlife species, particularly species of medium and large mammals whose increased energy demand, implies lower densities, larger areas of life and a higher probability of extinction. For the Cerrado biome in the state of Tocantins, studies on the medium and large mammal ecology communities are rare and punctual. In this context of ignorance, the objective of this study was to evaluate aspects of the ecology of medium and large mammal communities, as richness, similarity in habitat use, geographical distance on the similarity in species and periods of activity. The information presented in this study are the result of eleven years of work, monitoring and survey of medium and large mammalian fauna, conducted in development projects established in the Cerrado biome in the state of Tocantins. They recorded 47 species of medium and large mammals, representing 92.1% of the species recorded for the all Cerrado biome. Fourteen species are listed as endangered. The richness estimated by nonparametric estimator Jackknife first order was higher than the observed richness in all physiognomic types of vegetation studied, but the sampling efficiency was considered high, averaging 74.9%. Records of Aotus infulatus, Leopardus braccatus, Potos flavus, Sylvilagus brasiliensis and Dasyprocta prymnolopha were new and expanded the area of distribution of these species. The results for the agglomerative classification Dajoz, to the Jaccard similarity index, the cluster and principal component analysis allowed to infer a different distribution of species of medium and large mammals in relation to habitat use. The recorded species use all vegetation types of the study area but with a disjunct distribution of species in relation to them. In 80% of the regression analyzes, the influence of geographical distance on the similarity in species was not detected, not allowing inferences about different geographical distributions of species of medium and large mammals. The species, whose photographic records allowed the determination of periods of activity, showed diurnal behavior, predominantly diurnal, nocturnal, predominantly nocturnal and catemerais. The high richness in mammalian species, narrow dependencies and associations with vegetation types, the presence of endangered species and the fragility of the ecological community front to the increasing changes in their habitat, make urgent adoption public policy creation of conservation units to protect these and other species of the Cerrado biome of the Tocantins state

Species composition and frequency of habitat use by medium and large-sized mammals in the Brazilian Cerrado Biome, State of Tocantins

The Cerrado biome is the second largest natural vegetation type existing in Brazil after the Amazon, covering 91% of the State of Tocantins, with 30% of the territory changed as a result of the expansion of economic development areas. The substitution of natural vegetation means habitat loss on species, and may put the survival of medium and large-sized mammal species under extinction risk. These species represent significant energy demands and high requirements of area within the habitat. This study aims to assess the species composition and the frequency of use of physiognomic types of vegetation by medium and large-sized mammals. The study was conducted from 2001 to 2011 using a set of complementary and alternative techniques in fragments of seven different physiognomic types of vegetation. Fourth-seven medium and large-sized mammals were registered. This record corresponds to 92% of species already described within the biome, and five additional species to those registered in the data base of the State of Tocantins. Fourteen of these species are at certain degree of threat of extinction. The most used physiognomic types of vegetation in terms of canopy cover were Cerradao, Typical Cerrado, Riparian Forest and Dense Cerrado, and the less used were Gallery Forest, Campo Sujo and Vereda

Pervasive gaps in Amazonian ecological research

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

Canopy functional trait variation across Earth’s tropical forests

Tropical forest canopies are the biosphere’s most concentrated atmospheric interface for carbon, water and energy1,2. However, in most Earth System Models, the diverse and heterogeneous tropical forest biome is represented as a largely uniform ecosystem with either a singular or a small number of fixed canopy ecophysiological properties3. This situation arises, in part, from a lack of understanding about how and why the functional properties of tropical forest canopies vary geographically4. Here, by combining field-collected data from more than 1,800 vegetation plots and tree traits with satellite remote-sensing, terrain, climate and soil data, we predict variation across 13 morphological, structural and chemical functional traits of trees, and use this to compute and map the functional diversity of tropical forests. Our findings reveal that the tropical Americas, Africa and Asia tend to occupy different portions of the total functional trait space available across tropical forests. Tropical American forests are predicted to have 40% greater functional richness than tropical African and Asian forests. Meanwhile, African forests have the highest functional divergence—32% and 7% higher than that of tropical American and Asian forests, respectively. An uncertainty analysis highlights priority regions for further data collection, which would refine and improve these maps. Our predictions represent a ground-based and remotely enabled global analysis of how and why the functional traits of tropical forest canopies vary across space

Pervasive gaps in Amazonian ecological research

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

Pervasive gaps in Amazonian ecological research

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