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Background: Brazil Nuts (BN) tree is a species of high importance in Amazon region. Their continuous use by traditional communities is often related to disturbances that lead to larger degraded areas where this species is commonly found (“BN groves”). Here we aimed to explore the ecological patterns of BN groves vegetation and its relationship with BN trees and evaluate their potential as a source of carbon credits. We sampled 15 circular plots, with Brazilian Nut trees as the center (focal trees) and collected morphometric data from the focal trees. Additionally, we evaluated fruit production for a period of 5 years to obtain annual measurements, which were used as a proxy of the anthropic impact associated with the collection process. Through analysis of the data, we: i) examined the effects of BN trees on the adjacent vegetation; ii) quantified the potential amount of carbon credits in the adjacent vegetation and in the focal trees by converting carbon stock to equivalent CO2. Results: The adjacent vegetation structure was influenced by the size of BN trees (focal trees). No important effects of BN trees on the adjacent vegetation floristic composition and functional attributes were found. Additionally, we found that Brazilian Nut groves possess a significant potential for carbon credits that could be leveraged in the future carbon credit market, Conclusion: The study highlights the potential for carbon credit generation in Brazil nut groves in the Southeast Amazon as a means of supporting conservation and restoration efforts in these environments.

The restriction of access to natural resources by human populations due to the establishment and management of protected areas (PAs) can spark conservation conflicts (CCs) and undermine PA objectives. PAs have different management objectives and restriction levels; therefore, understanding the drivers, and the occurrence and importance of CCs in different groups of PAs is essential for conflict management. Herein, we built a conservation conflict hierarchical matrix (CCHM) using the information provided by the managers of 76 PAs in Brazil. We found that the restrictiveness of the PAs influenced the occurrence of CCs. We also found that the occurrence values of the CCs were lower in the Private Natural Heritage Reserves (PNHRs) compared to the values observed for the CCs in the full protection and sustainable use groups, which did not differ from each other. In addition, we noted that sustainable use PA managers indicated higher relative values of importance for most CCs compared to those indicated by full protection PA and private reserve managers. We also found that the drivers of the main conflicts depend on PA restrictiveness and that managers refer to environmental education as the main strategy to mitigate the conflicts. We concluded that different restriction levels in PAs promote different CC patterns and their respective drivers. Finally, given the different contexts and CCs experienced in different PAs, our results suggest that a collaborative approach between stakeholders using the CCHM can be beneficial to the management of local CCs.

Restaurar as florestas tropicais é essencial para enfrentar mudanças climáticas globais, manter e conservar a diversidade e os serviços ecossistêmicos. Foi analisado o estabelecimento e ocupação em três estratégias de restauração florestal (Plantio em Mudas em Área Total (PAT), Ilhas de Diversidade (ID) e Semeadura Direta (SD)) da vegetação florestal associada a cursos d’água. Foram avaliados: o número de indivíduos, intensidade de perfilhamento, biomassa acima do solo, área de copa, diâmetro e altura médios, por indivíduo, em 58 unidades amostrais (10 x 30 m) distribuídas entre as estratégias após 2,5 anos da implantação. Também foram avaliadas as principais espécies e suas similaridades entre as estratégias. A SD proporcionou maior efetividade quanto ao Número de indivíduos, Biomassa e Área de Copa, enquanto, a intensidade de perfilhamento foi maior nas ID e não houveram diferenças quanto a média de altura e diâmetro. Cada estratégia apresentou um conjunto particular de espécies de maior sucesso e as mais similares foram aquelas que utilizaram mudas (PAT e ID). A estratégia SD destacou-se no estudo, especialmente quando considerados aspectos ecológicos e custos envolvidos. As espécies contribuíram na diferenciação das estratégias, pois, proporcionaram funções ecológicas distintas que influenciam processos ecológicos em nível de comunidade e indivíduos. Palavras-chave: restauração florestal; nucleação; semeadura direta; plantio de mudas; floresta Amazônica. Effectiveness in the tropical forest restoration: how the differential performance of species and ecological context affect the establishment and occupation ABSTRACT: Restoring tropical forests is essential to address global climate change, to maintain and conserve diversity and ecosystem services. The establishment and occupation of three forest restoration strategies (Total Seedling Planting (PAT), Diversity Islands (ID) and Direct Seeding (SD)) of the forest vegetation associated with watercourses was analyzed. It were evaluated: the number of individuals, resprouting intensity, above-ground biomass, canopy area, average diameter and height, per individual, in 58 sample units (10 x 30 m) distributed among the strategies after 2.5 years of implantation. It was also evaluated the main species and their similarities between the strategies. The SD provided more effective as the number of individuals, biomass and treetop area, while the intensity of resprouting was higher in ID and there were no differences in mean height and diameter. Each strategy presented a particular set of most successful species and the most similar were those that used seedlings (PAT and ID). The highlight of the SD strategy is magnified when considering ecological perspectives, and social costs involved. The species contributed to the differentiation of strategies, because they provide distinct ecological functions that influence ecological processes at the community level and individuals. Keywords: forest restoration; nucleation; direct seeding; seedling planting; Amazon rainforest.

Flood forests are vegetation subject to seasonal floods. Situated in flood plains, they are systems under continuous changes due to the pulses of flooding, following the watercourse. Although these are singular ecosystems, there are little publications that report the floristic structure in floodplains, especially in Southeastern Brazil. This study aimed to characterize the composition, structure and diversity of the arboreal community in a flooding gradient, comparing them with the non-flood adjacent formations, at the mouth of Paracatu River, a tributary of São Francisco River, Minas Gerais, Brazil. For the structural survey of the arboreal community, we used the plot method, installed on both sides of Paracatu River. The individuals were identified at the species level. We sampled 1,276 individuals belonging to 85 species and 32 families. The Shannon Index (H`) regarding to the total sampling was of 3.40 nat.ind, with Pielou evenness index (J`) of 0.76. In terms of species importance, the six most important species comprised 46% of the total index of importance value. By means of similarity analysis, it was possible to verify the grouping of species along the ecounits, demonstrating the substitution of species along habitats, resulted of the temporal difference of the flooding in the environments. In conclusion, the flooding regimes, frequency and intensity determine the ecology of the river plains.

Aims We aimed at disentangling the effects of spatial distance, current and past environmental dissimilarity, and their combinations on tree community taxonomic and phylogenetic turnover by addressing the following questions: (i) Is tree community taxonomic and phylogenetic turnover related to the indirect effects of spatial distance via environmental dissimilarity? (ii) Does tree community taxonomic and phylogenetic turnover respond to paleoclimate (Last Glacial Maximum and Mid-Holocene)? Methods The study was carried out in 14 Atlantic rainforest sites in Brazil (20.4 ha sampled) containing 615 tree species from 83 plant families. We obtained plot-level geographic coordinates and soil variables and site-level bioclimatic variables in the current, Mid-Holocene and Last Glacial Maximum. We used structural equation models with a distance-based approach to (i) test the direct effects of spatial distance and environmental dissimilarity and (ii) test the indirect effects of spatial distance via environmental dissimilarity on taxonomic (Bray–Curtis distance) and phylogenetic turnover (Comdist and Comdistnt distances). Important Findings Our results suggest a weak indirect effect of spatial distance via environmental dissimilarity on taxonomic and phylogenetic turnover. Tree community turnover was driven by the direct effects of neutral, niche-based and historical processes. Thus, we inferred that the paleoclimate (historical processes) promoted the selection of the clades that gave rise to the current flora, while spatial distances (neutral processes) limited the dispersal range of species from the regional pool and environmental conditions (niche-based processes) locally selected the taxa that are able to persist.

Discrete thresholds of structural or functional decline of a vegetation type are not readily apparent, as a vegetation type can slowly decline leading to transformations in its species composition and weakened or altered functions. However, forest monitoring can be used to assess changes in ecological functions in community structure and functional and phylogenetic composition of species. This study evaluated the existence of temporal variations in the functional and phylogenetic composition of a tree community, the occurrence of heterogeneity in the behavior of phylogenetic and functional variations, and how this possible heterogeneity influences the functional and phylogenetic variations under the aspect of environmental variations and by demographic ecological processes. Results detected quantitative and qualitative changes throughout the community, such as colonization, local extinctions, in demography and biomass, and increased evolutionary distinction, lower wood density species and phylogenetic clustering. These results have shown us that the natural changes of a community should not be underestimated, because the disappearance of a community can not only occur by the direct elimination of vegetation, but can be incremental with gradual changes in its functional characteristics and species composition, transforming itself into a new community with a new combination of species and new functions., Los umbrales discretos de deterioro estructural o funcional de un tipo de vegetación no son fácilmente aparentes, ya que un tipo de vegetación puede disminuir lentamente, lo que lleva a transformaciones en la composición de sus especies y funciones debilitadas o alteradas. Sin embargo, las observaciones pueden usarse para evaluar los cambios en las funciones ecológicas antes de que esto ocurra a través de la estructura comunitaria y la composición funcional y filogenética de las especies. Este estudio evaluó la existencia de variaciones temporales en la composición funcional y filogenética de una comunidad arbórea; la ocurrencia de heterogeneidad en el comportamiento de variaciones filogenéticas y funcionales; y cómo esta posible heterogeneidad influye en las variaciones funcionales y filogenéticas bajo el aspecto de variaciones ambientales y por procesos demográficos ecológicos. Los resultados en la detección de cambios cuantitativos y cualitativos en toda la comunidad con la colonización y las extinciones locales en la comunidad, las diferencias demográficas y de biomasa, la distinción evolutiva aumentada, las especies de menor densidad de madera y el agrupamiento filogenético. Los resultados han demostrado que los cambios naturales de una comunidad no deben subestimarse, porque la desaparición de una comunidad no solo puede ocurrir por la eliminación directa de la vegetación, sino que puede ser incremental con cambios graduales en sus características funcionales y composición de especies, transformando en una nueva comunidad con una nueva combinación de especies y nuevas funciones.

In tropical montane forests, compositional and structural changes are commonly driven by broad-scale altitudinal variation. Here, given the lack of knowledge on small-scale vegetation changes and temporal dynamics, we address the effects of small-scale variations in soil and altitude on tree community structure, temporal dynamics and phylogenetic diversity in a semi-deciduous tropical forest of the Atlantic Forest Domain, southeastern Brazil. In 2010 and 2015 we sampled thirty plots of 400 m2, set up along an altitudinal gradient between 1000 and 1500 m a.s.l.. In each plot, we collected soil samples for chemical and textural analyses. We fitted linear models to test the effects of altitude and soil on community dynamics and phylogenetic parameters. Altitude and soil explained the spatial variation in number of individuals and phylogenetic diversity metrics. From lower to higher altitudes, we found decreasing fertility, increasing tree density and decreasing phylogenetic diversity. Altitude significantly influenced the increases in total biomass (from 240.9 to 255.4 t ha−1) and individual biomass (from 0.15 to 0.17 t) recorded in the interval. And while community temporal dynamics had rates of 1.96% for mortality, 1.02% for recruitment, 1.61% for biomass loss and 2.81% for biomass gain, none of them were explained by altitude or soil. Temporal species substitution averaged 0.1 in the interval. Altogether, these results suggest that the small-scale variations in altitude and soil likely determine the conditions and resources that drive community assembly and structure, which are expressed by spatial variations along the altitudinal gradient. At the same time, temporal patterns were not influenced by altitude-related environmental variation, resulting in a similar dynamic behaviour across the gradient, suggesting that broad-scale factors may play a more important role than local ones.

Studying community phylogenies along elevation gradients can inform us about the influences of environmental conditions on the structuring communities, and therefore allow predictions on how future environmental changes may affect them. The aim of the work was to evaluate the processes that govern tree communities along an altitudinal gradient in an upper montane Atlantic Forest in the Mantiqueira Range, southeastern Brazil. To do so, we analyzed the phylogenetic structure of angiosperm tree communities in four elevations (ranging from 1500 to 2100 m) and verified if it varies significantly with altitude. We also analyzed the phylogenetic beta diversity among local angiosperm tree communities along the altitudinal gradient. Further, we evaluated the soil and temperature influences over these communities. The results showed tendency of increasing phylogenetic clustering with the elevation. We also verified that the phylogenetic lineages of the tree communities are replaced along the altitudinal gradient influenced by changes in temperature and soil, indicating phylogenetic niche conservatism. This suggest that these communities could move to higher altitudes in a global warming scenario, and that would change their species composition and abundance due to changes in soil along the altitudinal gradient. Thus, the highest areas would be threatened as they would not have higher altitude locations to migrate to. In addition, phylogenetic lineages which only occur, or occur in their large majority, at highest altitudes (i.e., Cunoniaceae and Winteraceae) would be locally extinct by the current (or future) climatic scenario.

Estudos etnobotânicos no Brasil indicam uma forte relação entre comunidades locais detentoras de conhecimento ecológico tradicional e as plantas utilizadas. As áreas protegidas (AP) brasileiras podem funcionar como refúgios para essas populações, através do fornecimento de produtos florestais não-madeireiros de subsistência. Nosso objetivo foi explorar o estado atual das pesquisas etnobotânicas nas APs brasileiras para explorar seu escopo geográfico (regiões e biomas), as populações envolvidas e a ocorrência em diferentes categorias de AP. Para isso, realizamos um levantamento dos estudos publicados entre 2006 e 2019, totalizando 67 estudos. A Mata Atlântica é o bioma mais estudado, e a região nordeste é a principal região estudada. As populações tradicionais mais pesquisadas são agricultores artesanais e comunidades rurais. As APs de uso sustentável contêm a maioria dos estudos, mas a categoria Parque foi a mais pesquisada. O conhecimento sobre uso de plantas medicinais é o principal tema pesquisado nos estudos.

Made available in DSpace on 2022-04-28T19:44:20Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-01-01 Understanding the morphometry patterns of planted trees is an essential forestry methodology to develop accurate silvicultural practices. The genus Khaya comprises several economically important tree species due to its high quality of the wood and it has been broadly implemented in economical plantations. Here, we analyzed the morphometric characteristics of Khaya senegalensis (Desv.) A. Juss. from 484 trees in a 4 years-old plantation located in Southern Minas Gerais state, Brazil. Therefore, we measured the diameter at breast height (DBH), total height (TH), and crown insertion height (CIH). Using those variables, we estimated the crown length (CL), the slenderness ratio (SR), and the crown proportion (CP). The crown quality (CQ) and stem quality (SQ) were estimated by visual grading. We then performed regression models for all morphometric variables to analyze the distribution of each one. The survival analysis and mean annual increment at 4 years of age (48 months) were calculated. We used the Spurr model to estimate the population volume. The SR and CL variables showed high levels of variation. Most morphometric variables, except for SC, presented a significant correlation with DBH. The SQ and CQ presented a linear relationship with the size of the tree. As expected, tree diameter increased with the best quality of crowns and stems. We found a low morphometric relationship between TH and DBH. On the other hand, a linear trend was found with the increase of DBH, CL, and CP. The percentage of survival and the mean annual increment at 4 years of age were 97.2% and 3.31 m3/ha/year, respectively. The characterization revealed a good adaptation of the species within the plantation area in Southern Minas Gerais State. However, further and periodical analysis should create a robust database and make more assertive inferences of the morphometric variables. Universidade Federal de Lavras - UFLA, MG Universidade Estadual Paulista “Júlio de Mesquita Filho” - UNESP, SP Universidade Federal do Acre - UFAC, AC Universidade Estadual Paulista “Júlio de Mesquita Filho” - UNESP, SP

Aim of study: Aassessing the existence of consistent co-occurrence between tree species that characterize seasonal tropical forests, using the association rules analysis (ARA), that is a novel data mining methodology; and evaluate evaluating the taxonomic and functional similarities between associated species.Area of study: forty-four seasonal forest sites with permanent plots (40.2 ha of total sample) located in Southeast Brazil, from which we obtained species occurrences.Material and methods: we applied association rules analysis (ARA) to the dataset of species occurrence in sites considering the criteria of support equal to or greater than 0.63 and confidence equal to or greater than 0.8 to obtain the first set of associations rules between pairs of species. This set was then submitted to Fisher’s criteria exact p-value less than 0.05, lift equal to or greater than 1.1 and coverage equal to or greater than 0.63. We considered these criteria to be able to select non-random and consistent occurring associations.Main results: We obtained a final result of 238 rules for semideciduous forest and 11 rules for deciduous forests, composed of species characteristic of vegetation types. Co-occurrences are formed mainly by non-confamilial species, which have similar functional characteristics (potential size and wood density). There is a difference in the importance of co-occurrence between forest types, which tends to be less in deciduous forests.Research highlights: The results point to out the feasibility of applying ARA to ecological datasets as a tool for detecting ecological patterns of coexistence between species and the ecosystems functioning.Keywords: data mining; coexistence; semideciduous forests; deciduous forests; biotic interaction.

In the neotropical region, seasonally dry tropical forests (SDTF) are commonly associated with scatterly distributed limestone outcrops, known for harbouring high numbers of endemic species and genera. In the context of lacking knowledge on fine-scale vegetation and environmental heterogeneity of these geoecosystems and having a limestone outcrop in eastern Brazil as a case study, we address the question: how important are limestone outcrops for SDTF tree community composition, structure, function and evolution? We distinguished five habitats related to position and distance to the outcrop, and within each of 25 sampled plots (five per habitat), we identified and measured the diameter of all living tree individuals and collected soil samples for chemical and textural analyses. We investigated taxonomic and phylogenetic substitution across the habitats and fitted linear models to test the effects of habitat type, soil fertility and texture on taxonomic/structural, functional and phylogenetic parameters. We found striking taxonomic and phylogenetic differentiation among the habitats, especially related to recent diversification, with soil fertility and texture largely accounting for variations in all analysed parameters. Given the predominant roles of vicariance and in situ diversification believed to have given rise to the current patterns of endemism and diversity of eastern Brazil SDTF, we argue that the conditions presented by limestone outcrops, including aridity and high fertility, may have favoured the persistence of SDTF lineages during the Quaternary environmental changes, highlighting their role as litho-refugia. In order to complete this biogeographic puzzle, we encourage other fine-scale assessments of outcrop-associated SDTF from the phylogenetic viewpoint.

Species–habitat associations can be used as a proxy for species niches. Previous research has shown that niche plasticity may increase diversity in plant communities, and that plasticity may be linked to variations in species fitness. Spatial and temporal aspects of the niche are of interest to understand community structure, but the temporal dimension is often difficult to incorporate in ecological research. In this study, we investigated if species–habitat associations are stable across time, and if they are not, whether niche plasticity promotes variations in species fitness and increases in diversity. We modeled the representativity of 36 species as a function of soil variables and slope in an Atlantic tropical wet forest located in southeast Brazil, as well as their interactions with time, monitored over a period of 17 years. We found niche plasticity to be a common mechanism among the studied species in the studied time period. Niche plasticity was neither significantly related to variations in species fitness nor to changes in species richness, but had a negative effect on diversity when species abundance was accounted for (Shannon and Simpson indexes). We were able to make relevant observations of species–environment relationships over time, such as their niche stability and its effects on the community. We argue that this knowledge is useful in a context of climate change for revealing mechanisms used by plants to cope with environmental oscillations.

Our work aimed to test the hypothesis that soil microscale heterogeneity act as a community ecological driver, increasing diversity and promoting structural shifts on the Seasonally Dry Tropical Forest (SDTF) tree community. We evaluated the relationship between microscale edaphic variations and floristic–structural patterns of tree communities in a SDTF fragment located in the southern end of the Brazilian Caatinga domain. Vegetation and soil data were obtained through 27 sample units of 400 m2 (20 m × 20 m), within each one we measured and identified at species level all arboreal individuals with Circumference at the Breast Height greater or equal to 10 cm, and also collected the soil samples. Through the data we evaluated soil variation influence on the tree community structural and floristic patterns trough generalized linear models. Soil explained the small-scale structural and floristic variations, contributing significantly to biomass, sprouting and to floristic relationships between sample units. It was also observed a possible relation of the result with the Caatinga domain biogeographic history, due the presence of Sedimentary Caatinga species, which are not expected for the study region. Soil plays an important role in driving small-scale complexity and diversity of SDTF, but we also suggest that Caatinga biogeographic events have influence on the high heterogeneity patterns.

Understanding vegetation-environment relationships enables perceiving past and present patterns and to predict responses to future scenarios, thereby being useful for conservation and understanding evolutionary processes. In this context, the objective of our study was to test the hypothesis that niche processes at local scales (< 1 km2) are significantly expressive in plant communities structuring. For this, we selected the more representative and widely distributed sampled species, and then modelled their representativeness as a function of edaphic variables. The data were obtained in four fragments of seasonal semi-deciduous forests located in a transition area between the Atlantic and Cerrado biogeographic domains, Brazil. A total of 92 plots with 63 of 400 m2 and 29 of 300 m2 were randomly distributed in the fragments. Individuals that reached the inclusion criterion (circumference at breast height ≥ 15.7 cm) in each plot were measured and identified and soil samples were also collected. Then, we calculated the relative abundance and relative basal area in each plot. All species showed significant relationships with the soil variables, as their representativeness showed to be correlated (positively and/or negatively) with at least one restrictive fertility or texture condition. Therefore, the results confirm the tested hypothesis, evidencing the niche processing role in community structuring through the species tolerance degree to soil conditions.

Background: Seasonally Dry Tropical Forests (SDTF) are recognized by their great biological diversity, but little is known about their temporal patterns, which may be crucial in a changing world. Here we aimed to characterize the SDTF dynamic patterns in floristic and structural changes, and also to evaluate shifts in dynamic rates and structural attributes such as richness, number of trees and biomass. Our hypothesis is that SDTF tree communities have their dynamic characterized by temporal fluctuations related to an instability pattern, in according to the already found for others tropical forests. For this we used a data of 42 400 m² plots in three fragments in the Brazilian Arboreal Caatinga, measured in 2005, 2010 and 2015. We evaluated temporal changes in richness, species composition, trees density, biomass and rates of tree mortality and recruitment; and also rates of biomass gain and loss. Results: We found a pattern of floristic composition stability, but with changes in structure and dynamics. There was a tree density decrease driven by constant mortality and by recruitment decrease, and biomass increase due to decrease in biomass loss and to increase in biomass gain. The biomass increase was main related to a small set of dominant species that are the most representative in the community dynamics. Conclusion: SDTF dynamics are related to stability in species composition, but with structural changes towards higher biomass stocks. The results are main related to community dynamics and to SDTF attributes such as climatic seasonality that drives the local ecological processes.

A Área de Proteção Ambiental Serra de São José e o Refúgio Estadual de Vida Silvestre Libélulas da Serra de São José, localizadas na região de Tiradentes-Minas Gerais, apresentam importante diversidade biológica para a conservação, distribuídas em três fitofisionomias: Cerrado, Floresta Estacional Semidecidual e Campos Rupestres. Além de protegerem legalmente o patrimônio natural, abrigam também raizeiros que detêm saberes e práticas sobre o uso de espécies vegetais extraídas nos limites das referidas áreas. Com o objetivo de compreender os conflitos estabelecidos na relação entre a conservação e uso de espécies vegetais, foram realizados levantamentos etnobotânicos por meio de turnês guiadas em três trilhas utilizadas por dois raizeiros, e aplicado questionário semiestruturado, que apontaram as espécies utilizadas, suas aplicações (passado e presente) e as partes empregadas. Concluiu-se, que os conflitos existentes se devem à extração de recursos biológicos na Unidade de Conservação de proteção integral. Todavia, podem contribuir para conservação da biodiversidade das Áreas Protegidas da Serra de São José juntamente com a da etnobotânica e a participação efetiva dos raizeiros. Protection Area Serra de São José and the State Refuge of Wildlife Libélulas of Serra de São José, located in the region of Tiradentes-Minas Gerais present important biological diversity for conservation distributed in three phytophysiognomies: Cerrado, Semideciduous Seasonal Forest and Rupestres Fields. In addition to legally protecting the natural heritage, they also shelter “raizeiros” that have knowledge and practices about the use of plant species extracted within the limits of the mentioned areas. Aiming to understand the conflicts established in the relationship between the conservation and the use of plant species, ethnobotanical surveys were conducted through guided tours in three tracks used by the two “raizeiros”, and a semistructured questionnaire was used in order to indicated the species used both in past and presente, and also the employed parts. It was concluded that the existing conflicts are due to the extraction of biological resources in the Conservation Unit of integral protection. However, they can contribute to the conservation of the biodiversity of the Serra de São José Protected Areas concomitantly with the ethnobotany one, and the effective participation of the “raizeiros”.

Tropical forests have played an important role as a carbon sink over time. However, the carbon dynamics of Brazilian non-Amazon tropical forests are still not well understood. Here, we used data from 32 tropical seasonal forest sites, monitored from 1987 to 2020 (mean site monitoring length, ~15 years) to investigate their long-term trends in carbon stocks and sinks. Our results highlight a long-term decline in the net carbon sink (0.13 Mg C ha-1 year-1) caused by decreasing carbon gains (2.6% by year) and increasing carbon losses (3.4% by year). The driest and warmest sites are experiencing the most severe carbon sink decline and have already moved from carbon sinks to carbon sources. Because of the importance of the terrestrial carbon sink for the global climate, policies are needed to mitigate the emission of greenhouse gases and to restore and protect tropical seasonal forests.

Resprouting is an ecological strategy widely adopted by trees in response to different restrictive factors, in which the stems can be emitted at different heights of the tree. Although the patterns of resprouting height are already known in response to some restrictive factors (such as fire), their occurrence is not well elucidated in non-fire prone dry environments where continuous resource restriction may stimulate resprouting. Here, we assessed the general ecological dominance of resprouting trees in the community and the ecological dominance of trees resprouting at different heights in response to environmental restrictions in a tropical dry forest (TDF). We used multi-stemmed trees as a proxy for resprouting in response to the local restrictive factors. Our hypotheses were: i) resprouting trees have greater ecological dominance (more trees and stems and higher biomass) in more restrictive plots; ii) the ecological dominance of lower-height resprouting trees is greater in more restrictive plots, while the dominance of upper-height resprouting trees is greater in less restrictive plots. For this, we used a dataset of 27 TDF plots where we measured and identified the trees that met the inclusion criterion (3 cm of diameter at breast height) and collected soil samples to gather data on environmental restriction. Multi-stemmed trees were classified according to the height of additional-stem emission (below-ground, ground-level, and above-ground), considering the bottom-most stem originating from the main stem. We then evaluated whether the ecological dominance of resprouting trees and trees with different resprouting heights varied significantly in response to environmental restrictiveness, and patterns of species composition in the height categories. We found a greater dominance of resprouting trees in more restrictive environments, with lower-height resprouting trees dominating the most restrictive plots (two hypotheses confirmed). This finding may be associated with physiological mechanisms of drought response because resprouting height is directly associated with the level of damage inflicted on the internal structure of trees. We also found that the species varied in their ability for stem emission at different heights, whereby the most plastic species were more dominant compared to those with just one height of emission. This finding indicates that different restrictive factors can produce similar resprouting expressions, reinforcing the need to advance the knowledge on the importance of resprouting in TDF.

Riverine forests in the Brazilian Amazon provide a series of ecosystem services and harbor one of the world's most diverse floras, but the main drivers of variation in small spatial scales in such tropical forests are not well understood. Our aim was to evaluate tree community structure and diversity patterns in the Teles Pires River to identify the main drivers of small-scale variations in the area. We sampled 4,180 individuals from 49 botanical families, 164 genera and 347 species by using six transects of five pairs of 50 m x 40 m permanent plots totalizing 60 permanent plots in a 12-hectare area. We utilized generalized linear mixed models to assess whether the effects of the environmental variables in the vegetation structural parameters. Altitude and groundwater depth were the main drivers influencing species diversity patterns. The trees had similar total biomass in areas within the same distance from the river margins. There was a lower species richness and tree density closer to the river margins. Otherwise, we found larger trees (higher individual biomass) closer to the river margins when compared to areas distant from the margins. Our results indicate a high species turnover from the river margins to the forest interior, which highlights the importance of assessing local effects on biological communities in tropical forests, especially in the Brazilian Amazon where several high-impact dams are planned.

The relationship between biodiversity and ecosystem functioning is one of the most currently acclaimed ecological topics. One remarkable aspect of tree communities in tropical forests and savannas is the concentration of individuals into few species or simply the species stem dominance. In addition, species dominance in biomass and productivity are indicators of how much it can affect ecosystem processes. Here, we investigated if tree species dominance in abundance is followed by a dominance in biomass and productivity, and if there is consistence in the functional traits associated to dominance in biomass, productivity, and stem abundance in neotropical savannas of Central and Southeastern Brazil. Our findings showed slightly stronger functional (biomass and productivity) dominance compared to the abundance dominance, with 3.4 and 4.2% of the species accounting for 50% of the biomass and productivity, respectively, and 4.3% of the species accounting for 50% of the individuals. There were overlaps, but mostly mismatches, between dominant species lists for biomass, productivity, and abundance, especially in the top three species. We found that the same traits which make a species capable to deal with savanna environmental odds (i.e., adaptations) and achieve high abundance, also make it possible for this species to reach larger diameters and consequently dominance in biomass. Species relative contributions to productivity responded to bark thickness, wood density and maximum potential size. The fact that just a few species concentrate most savanna trees, biomass, and productivity show a high level of adaptation of this species to the environmental conditions found in this biome. Regardless, the conservation of the entire pool of species is crucial because climate change, land use and species invasion might cause shifts in the vegetation structure and function.

O ecoturismo é considerado uma atividade com potencial baixo impacto ambiental, geradora de benefícios sociais e, dependente da existência de atrativos naturais. Mas como os indivíduos autóctones percebem essa atividade e se relacionam com suas áreas naturais? O objetivo, neste estudo, foi analisar em que nível os indivíduos autóctones se envolvem com os ambientes naturais com potencial ecoturístico e como os percebem em uma localidade em fase inicial de desenvolvimento de práticas ecoturísticas, e a dinâmica desse envolvimento e percepção, a partir do olhar dos jovens, em dois períodos com intervalo de nove anos. Para isso, utilizou-se da iconografia com apresentação de dez fotografias de ambientes com potencial ecoturístico da localidade de Luminárias, Minas Gerais - Brasil, para estudantes do ensino médio, com posterior aplicação de um questionário semiestruturado, nos anos de 2007 e 2016. Empregou-se ainda a técnica de observação participante. Como resultado, os ambientes naturais com potencial ecoturístico foram reconhecidos em diferentes níveis e considerados como de alta atratividade, mas seu uso turístico é de baixo envolvimento com os indivíduos autóctones. Os resultados demonstraram ainda que, na dificuldade de uma mobilização contínua que alcance a população, os ambientes escolares mostram-se como espaços facilitadores para o processo de sensibilização e inserção social no planejamento do ecoturismo.

The new environmental conditions imposed by disturbance events often create a mosaic of spots in different successional stages. Our objective was to describe the temporal variation of a semideciduous seasonal forest based on its anthropic disturbance history, verifying possible changes in forest dynamics and structure. We sampled the arboreal vegetation with a diameter at breast height (1.3 m above the ground; DBH) ≥ 5 cm in 15 permanent plots of 20 × 20 m where we performed four inventories (2003, 2005, 2007 and 2015). We observed a density decrease and a basal area increase, which indicates the late successional stage of the analyzed tree community. The phytosociological structure, richness and species diversity of the tree community did not show changes throughout the monitoring. However, the Protium spruceanum predominance may be a response to the environmental changes caused by the mining occurred in the area 250 years ago. The anthropic disturbances enduring influences make this type of work indispensable because it allows the ecological processes understanding, allowing a factual management of the forests by the its effective management and conservation. Resumo As novas condições ambientais impostas por eventos de distúrbios criam um mosaico de manchas em diferentes estágios sucessionais. Nosso objetivo foi descrever a variação temporal de uma floresta estacional semidecidual em função do histórico de perturbação antrópica, verificando possíveis mudanças na dinâmica e estrutura da floresta. Nós amostramos a vegetação arbórea com diâmetro a 1,3 m do solo (DAP) ≥ 5 cm em 15 parcelas permanentes de 20 × 20 m onde realizamos quatro inventários (2003, 2005, 2007 e 2015). Nós verificamos uma diminuição da densidade e aumento da área basal, o que indica que a comunidade arbórea analisada se encontra em estágio tardio de sucessão. A estrutura fitossociológica, a riqueza e a diversidade de espécies da comunidade arbórea não apresentaram mudanças ao longo dos monitoramentos. Entretanto, o predomínio da espécie Protium spruceanum pode ser uma resposta às mudanças ambientais provocadas pela mineração que ocorreu na área há 250 anos. As influências duradouras dos distúrbios antrópicos tornam este tipo de trabalho imprescindível por permitir a compreensão dos processos ecológicos, possibilitando um gerenciamento factual das florestas pelo manejo e conservação efetivos.

Forest dynamics are driven by a myriad of factors and link directly to ecosystem services. The dynamics of the highly degraded Brazilian Atlantic Forest (AF) hotspot is mostly driven by its anthropogenic context. Currently, most of the AF region is composed of small disturbed secondary forest fragments that have received partial or full environmental protection with recent environmental norms. Such protection prevents further disturbances and consequently shifts the course of forest dynamics and ecosystem services in AF. Here, we assess long-term forest dynamics trends of a small secondary AF fragment to test the hypothesis that disturbed AF fragments are reaching advanced successional stages. We used a unique dataset of 126 permanent subplots (totaling 5.04 ha) monitored for 30 years (8 inventories between 1987 and 2017) of a disturbed secondary AF fragment (6.35 ha) that has been fully protected since 1986. In each inventory, we measured all living trees with a diameter at breast height (DBH) ≥ 5 cm and counted survivors, recruits and dead individuals between intervals. We monitored the temporal trends of (i) structural variables (biomass, tree density and species richness), (ii) functional composition (wood density and maximum potential size), (iii) and species dominance. Our results indicate that, now under full protection, the fragment is shifting towards a late successional stage: we observed increasing biomass, decreasing tree density (self-thinning) and increasing abundance of late-successional species with conservative strategies. Species richness and dominant species composition were stable throughout the monitoring period, suggesting an absence of substantial changes in community assembly. These results underscore the role played by small secondary AF fragments in ecosystem service provision (e.g., carbon uptake and shelter for biodiversity) and point to their forest dynamics trends.

Obtaining high-quality information on vegetation attributes directly linked to ecosystem services in tropical forests, such as carbon stock and biodiversity, is essential to develop ecological information to be used in planning conservation strategies. Defining the optimum vegetation sample plots size is an important part of the process of obtaining information, since is crucial for its quality, and also for its financial costs and time required. In this context, we evaluated whether: (i) the optimum plot size selected in two approaches (basal area/carbon stock vs biodiversity) are different since they are associated with different ecological drivers; (ii) different tropical forests vegetation types present different optimum sample plot size due to their ecological specific attributes, such as species composition, structure and functioning. For this we evaluated the vegetation sample plots optimum size of different vegetation types of tropical savanna and forest of broad occurrence in the tropics (Atlantic Semideciduous Forest – ASF; Cerrado Woodland – CW; Cerrado Forest – CF; and Seasonally Dry Tropical Forest - SDTF), in two approaches: forest basal area and carbon stock, since they are related variables; and biodiversity variables by species composition similarity and heterogeneity in communities. We used 4 forest fragments in Brazil that were sampled in a way that allowed the arrange of subplots to form different plot sizes. In order to evaluate the optimum sample plot size in the basal area/carbon stock approach we used four methodologies, in which the obtained variability was compared to a reference size (1000 m2). For the biodiversity approach we used the floristic similarity and composition heterogeneity between units as metric, evaluating differences in the similarity patterns and possible reductions or increases in variability compared to the reference size. We found there are no significant differences for biodiversity variables between sample plot sizes for all vegetation types, thus the optimum size may be selected using just the basal area/carbon stock approach. In the basal area/carbon stock approach, most of the evaluated methods generally presented lower plot size values compared to the reference size (1000 m2) in all vegetation types, except for the ASF. There are differences between vegetation types that may be grouped in two groups related to the optimum size selected, that are related to their ecological restriction patterns: CW, CF and SDTF with optimum size between 600 and 1000 m2; and the second with ASF, with optimum sample plot size between 1000 m2 and 1400 m2.

A Área de Proteção Ambiental Serra de São José e o Refúgio Estadual de Vida Silvestre Libélulas da Serra de São José, localizadas na região de Tiradentes-Minas Gerais, apresentam importante diversidade biológica para a conservação, distribuídas em três fitofisionomias: Cerrado, Floresta Estacional Semidecidual e Campos Rupestres. Além de protegerem legalmente o patrimônio natural, abrigam também raizeiros que detêm saberes e práticas sobre o uso de espécies vegetais extraídas nos limites das referidas áreas. Com o objetivo de compreender os conflitos estabelecidos na relação entre a conservação e uso de espécies vegetais, foram realizados levantamentos etnobotânicos por meio de turnês guiadas em três trilhas utilizadas por dois raizeiros, e aplicado questionário semiestruturado, que apontaram as espécies utilizadas, suas aplicações (passado e presente) e as partes empregadas. Concluiu-se, que os conflitos existentes se devem à extração de recursos biológicos na Unidade de Conservação de proteção integral. Todavia, podem contribuir para conservação da biodiversidade das Áreas Protegidas da Serra de São José juntamente com a da etnobotânica e a participação efetiva dos raizeiros.

The resilience or sensitivity of seasonally dry tropical forests (SDTF) to climate change remains an important issue because of their biodiversity and ecosystem services provision. Understand the underlying ecological processes of SDTF is crucial for the development of conservation and management strategies. We tested the hypotheses that SDTF tree species richness, above-ground woody biomass (AGWB), species and phylogenetic compositions are related to climate, soil and their interactions. We sampled 16 old-growth forest sites (313 plots) of SDTF within a 290 km latitudinal gradient. The sites are located in the transition zone between Caatinga and Cerrado biogeographic domains, and are near from Atlantic domain (~100 km). In each site we collected data on vegetation (trees with diameter at breast height ≥3 cm) and soil, and obtained climate data from WorldClim. Almost all vegetation attributes were significantly related to climate and soil. Soil texture mediated the effects of precipitation for tree species richness, AGWB and phylogenetic composition. Tree species richness decreases with annual precipitation but increases under less seasonal conditions; water availability leads to increases in AGWB and drives changes in both taxonomic and phylogenetic composition in these environments. Our findings indicate that tree species richness, above-ground woody biomass, taxonomic and phylogenetic composition of SDTFs are, in general, vulnerable to drought events even from local to regional scales and show the importance of local-scale aspects to understand SDTF diversity and ecosystem functioning; and provide useful information for conservation and management strategies.

Studies about the birds of rupestrian fields in the south of Minas Gerais State in Southeastern Brazil are incomplete, although this region is ornithologically well studied. This bird community has closely associated ecology with fields and the most endangered species of the Cerrado domain. The objective of this manuscript is to create a list of birds which occur in the rupestrian fields of seven municipalities in the south of Minas Gerais State, and further to analyze the birds’ distribution, the endangered species (and their conservation status), and generate bases for future conservation actions. We evaluated seven cities in the south of Minas Gerais State between 2012 and 2018 by using binoculars and cameras. We found a high richness in relation to other open areas, with the Tyrannidae and Trochilidae families being the most representative. We highlight the endangered species in the Cerrado domain which of these species are closely linked to rupestrian fields. The composition is similar to closer areas, with exception to São Thomé das Letras city because it suffers an influence of mining areas. We suggest creating a wildlife protected area to preserve and conserve a great area of rupestrian fields and consequently the associated biota, especially the bird communities Studies about the birds of rupestrian fields in the south of Minas Gerais State in Southeastern Brazil are incomplete, although this region is ornithologically well studied. This bird community has closely associated ecology with fields and the most endangered species of the Cerrado domain. The objective of this manuscript is to create a list of birds which occur in the rupestrian fields of seven municipalities in the south of Minas Gerais State, and further to analyze the birds’ distribution, the endangered species (and their conservation status), and generate bases for future conservation actions. We evaluated seven cities in the south of Minas Gerais State between 2012 and 2018 by using binoculars and cameras. We found a high richness in relation to other open areas, with the Tyrannidae and Trochilidae families being the most representative. We highlight the endangered species in the Cerrado domain which of these species are closely linked to rupestrian fields. The composition is similar to closer areas, with exception to São Thomé das Letras city because it suffers an influence of mining areas. We suggest creating a wildlife protected area to preserve and conserve a great area of rupestrian fields and consequently the associated biota, especially the bird communities