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Savannas and grasslands have lost almost 50% of their original cover worldwide. Therefore, the development of methods and information on open-canopy ecosystem restoration is urgent for the inclusion of these ecosystems into global and regional priorities. In the Brazilian savanna, the most diverse savanna in the world, restoration efforts focused on open ecosystems have been virtually absent, but have increased in the last 10 years. Such efforts are frequently threatened by invasive exotic grasses (IEG) that invade and dominate areas excluding native species, oftentimes aided by altered soil conditions. Long-term studies of savanna restoration trajectories are rare. In this study, we surveyed 22 savanna restoration areas established two to ten years before the study with similar restoration methods to assess their current status. We show that the current restoration methods are successful in establishing native species and allowing species turnover but they are threatened by IEG. Restoration success varies and is affected by soil conditions, IEG landscape cover and post-sowing weeding. Despite that, the simultaneous introduction of different plant functional groups allows turnover from fast to slow-growing plants. Establishing savanna native species is possible at an operational scale with current knowledge and techniques. However, native species establishment fails to prevent IEG reinfestation, which needs to be managed in restoration efforts in the Brazilian savanna.
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Conservação dos Recursos Naturais , Pradaria , Brasil , Poaceae/crescimento & desenvolvimento , Ecossistema , Espécies IntroduzidasRESUMO
Forest and landscape restoration is one of the main strategies for overcoming the environmental crisis. This activity is particularly relevant for biodiversity-rich areas threatened by deforestation, such as tropical forests. Efficient long-term restoration requires understanding the composition and genetic structure of native populations, as well as the factors that influence these genetic components. This is because these populations serve as the seed sources and, therefore, the gene reservoirs for areas under restoration. In the present study, we investigated the influence of environmental, climatic and spatial distance factors on the genetic patterns of Plathymenia reticulata, aiming to support seed translocation strategies for restoration areas. We collected plant samples from nine populations of P. reticulata in the state of Bahia, Brazil, located in areas of Atlantic Forest and Savanna, across four climatic types, and genotyped them using nine nuclear and three chloroplast microsatellite markers. The populations of P. reticulata evaluated generally showed low to moderate genotypic variability and low haplotypic diversity. The populations within the Savanna phytophysiognomy showed values above average for six of the eight evaluated genetic diversity parameters. Using this classification based on phytophysiognomy demonstrated a high predictive power for genetic differentiation in P. reticulata. Furthermore, the interplay of climate, soil and geographic distance influenced the spread of alleles across the landscape. Based on our findings, we propose seed translocation, taking into account the biome, with restricted use of seed sources acquired or collected from the same environment as the areas to be restored (Savanna or Atlantic Forest).
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In fire-prone ecosystems, plant traits are influenced by the fire regime, thus reproduction and establishment can be altered by this disturbance. Changes in fire frequency and history can therefore influence seed and germination traits. We investigated the effects of short-term fire exclusion on seed and germination traits of species from tropical open savannas. Seeds from 27 species were collected from two areas with distinct fire histories: recently and frequently burned (RB) or unburned for 5 to 7 years (E). Seeds from both areas underwent germination trials under optimal conditions for 30 days. Also, 10 species were exposed to high temperature treatments (100 or 200 °C) and seed and germination traits measured. Comparisons were then made for each trait, analysing each species separately, between the two areas. Approximately 85% of species studied had at least one of their germination traits altered in the RB area compared to the E area. Clear differences included lower viability and faster germination in seeds from RB areas. Seed traits of 70% of measured species differed between the two areas. Our results show species-specific trait response to different fire histories. For example, faster germination and lower viability of seeds from RB plots suggest selection for faster maturing individuals and differences in resourcing, respectively, under a regime of frequent fire. This study provides insights into fire effects on regeneration responses of tropical savanna species and also points to the need for more studies evaluating the effects of fire history on seed traits.
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Brazil's major beef production occurs in the Cerrado, predominantly as extensive pastures that covers â¼50 Mha of the biome, of which approximately 2/3 show signs of degradation. Pasture recovery is now a key environmental policy, as it improves land use efficiency and soil carbon sequestration. However, as intensification leads to higher cattle stocking rates and external inputs (fertilizers, liming, etc.), the impact of improved pastures on greenhouse gas mitigation is still debatable. This study focused on the Cerrado biome and aimed to (i) quantify soil carbon stock changes under different scenarios of management and recovery of degraded pastures. In addition, (ii) the potential for capturing carbon in the soil to mitigate emissions of greenhouse gases (GHG) by the intensification of pastures was evaluated. Soil C stock changes (0-20 cm) were assessed using the Century model version 4.5, which had been previously validated for the region. Model parameters were adjusted for three pastures classes (degraded, intermediately degraded, and not degraded) within a time-series (1985-2020) of land use maps for the Cerrado, serving as baselines. Scenarios of pasture intensification were modeled against these baselines, and an analysis was carried out on the estimated changes in soil C stock and greenhouse gas balance. Before the intensification scenario (year 2020), the total carbon stock was estimated to be â¼1830 Mt for the whole pasture area, whose spatial distribution corresponded to edaphoclimatic contrasts and pasture conditions. The highest soil organic carbon stocks were observed in the non-degraded pastures. With the increase in carrying capacity, beef production is estimated to potentially increase by 1/3 due to the recovery of degraded areas through intensive management. This increase would be sufficient to meet the projected â¼12% increase in Brazil's livestock production by the end of the decade if all pasture areas are restored, which is much possibly an unrealistic scenario as not all degraded areas are suitable for crops or can successfully improve pasture yield. In addition, the increase in soil C stocks was only sufficient to compensate for 27% and 42% of the GHG emissions resulting from intensification in areas with intermediate and severe degradation, respectively. Therefore, to strike a balance between economic considerations and environmental impact, additional strategies are needed to reduce GHG emissions and/or enhance C sinks, such as increasing tree density on farms. From this perspective, implementing livestock intensification at the landscape scale can promote C stocks and the diversity of ecosystem services, opening the possibility of ecosystem restoration.
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Ecossistema , Gases de Efeito Estufa , Animais , Bovinos , Solo , Gases de Efeito Estufa/análise , Brasil , Gado , Pradaria , Carbono/análise , AgriculturaRESUMO
Mercury (Hg) is a chemical element that, depending on its concentration, may become toxic to living organisms due to the ability of Hg to bioaccumulate in food chains. In this study, we collected samples of soil, litter, and organisms in the Middle Araguaia floodplain, Brazil. Total mercury (THg) concentrations in litter were significantly higher (p < 0.0001) than that in soil, ranging from 10.68 ± 0.55 to 48.94 ± 0.13 and 20.80 ± 1.07 to 55 .19 ± 1.59 ng g-1, respectively. Total mercury concentration levels in soil showed a linear, inversely proportional relationship with soil organic matter (SOM) contents and soil pH, consistent with the geochemical behavior of chemical elements in flooded environments. Ten orders of organisms were identified, and the average THg concentrations determined in their bodies were up to 20 times higher than those in soil and litter. We found a significant linear relationship between the levels of THg in litter and those found in soil organisms, thereby allowing the prediction of THg concentration levels in soil organisms through the analysis of litter at the sample units. The different dynamics and feeding habits of soil organisms and the concentration of THg in these organisms may be influenced by the river's course. This study provides evidence of the bioaccumulation of THg in soil organisms in the floodplain of the Middle Araguaia River, an important river basin in the Brazilian savanna.
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Mercúrio , Poluentes Químicos da Água , Mercúrio/análise , Brasil , Solo , Poluentes Químicos da Água/análise , Cadeia Alimentar , Monitoramento AmbientalRESUMO
The Araguaia River floodplain is an important biogeographic boundary between the two largest South American biomes: the Cerrado (Brazilian Savanna) and the Amazon rainforest. The large-scale degradation due to land use conversion experienced in the Araguaia River watershed represents a potential source of mercury (Hg) transport to aquatic ecosystems. However, more information is needed about the dynamics of Hg distribution in savanna floodplains, including the Araguaia River floodplain. We analyzed total mercury (THg) concentrations in the bottom sediments of 30 lakes connected to the Araguaia River and four tributaries, aiming to evaluate the environment's integrity based on the geoaccumulation index (Igeo) and the ecological risk index (ERI). The principal component analysis was applied to examine associations between Hg concentrations, environmental conditions, and land use intensity among lakes associated with different river systems. We used indicator cokriging to identify areas with a greater probability of Hg pollution and ecological risk associated with land use intensity. The land use data showed the predominance of areas used for pasture in the Araguaia River basin. THg concentrations in the sediments varied between 22.6 and 81.9 ng g-1 (mean: 46.5 ± 17.7 ng g-1). Sediments showed no significant pollution (Igeo: 1.35 - 0.50; Classes 1 and 2) and low to considerable ecological risks (ERI: 23.5-85.1; Classes 1 to 3). THg in bottom sediments was associated with land use, water turbidity and electrical conductivity, and sediment organic matter. The indicator cokriging indicates a moderate to strong spatial dependence between land use intensity and Hg, confirming the contribution of anthropic sources to the increment of ecological risk but also the influence of extrinsic factors (such as environmental conditions, geology, and hydrology). Integrating sediment assessment and land use indices with geostatistical methods proved a valuable tool for identifying priority areas for Hg accumulation at a regional scale.
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Mercúrio , Poluentes Químicos da Água , Mercúrio/análise , Rios , Lagos , Brasil , Ecossistema , Pradaria , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Sedimentos Geológicos/análiseRESUMO
The Cerrado confronts threats such as fire and frost due to natural or human-induced factors. These disturbances trigger attribute changes that impact biodiversity. Given escalating climate extremes, understanding the effects of these phenomena on ecological relationships is crucial for biodiversity conservation. To understand how fire and frost affect interactions and influence biological communities in the Cerrado, our study aimed to comprehend the effects of these two disturbances on extrafloral nectar (EFN)-bearing plants (Ouratea spectabilis, Ochnaceae) and their interactions. Our main hypothesis was that plants affected by fire would grow again more quickly than those affected only by frost due to the better adaptation of Cerrado flora to fire. The results showed that fire accelerated the regrowth of O. spectabilis. Regrowth in plants with EFNs attracted ants that proved to be efficient in removing herbivores, significantly reducing foliar herbivory rates in this species, when compared to the species without EFNs, or when ant access was prevented through experimental manipulation. Post-disturbance ant and herbivore populations were low, with frost leading to greater reductions. Ant richness and diversity are higher where frost precedes fire, suggesting that fire restores Cerrado ecological interactions better than frost, with less impact on plants, ants, and herbivores.
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This research aims to describe the process of ecological succession by associating the decomposition stages of pig carcasses with flies from the Calliphoridae family (Diptera). For this, 6 pig carcasses were exposed in Maranhão's Cerrado, utilizing metal cages with sawdust trays to catch immature specimens and "suspended traps" to capture adults. Adults of the Hemilucilia benoisti Séguy, and Hemilucilia townsendi Shannon species were only associated with the swelling stage. Chrysomya megacephala (Fabricius) was associated with 2 stages (black putrefaction and fermentation). The species Chloroprocta idioidea (Robineau-Desvoidy), Chrysomya albiceps (Wiedemann), Cochliomyia macellaria (Fabricius), and Lucilia eximia (Wiedemann) were associated with 4 of the 5 stages of decomposition, the latter being the only 1 associated with the initial stage. The larvae abandoned the carcasses to pupate from the second stage of decomposition, with L. eximia being the only 1 leaving the carcasses in the swelling stage, and C. albiceps the only 1 associated with both the fermentation and dry stages. Our findings indicate that calliphorid species can help forensic investigators estimine the post-mortem interval of cadavers in situations similar to those detailed in this study. Since there was a link between adult and immature species and certain stages, they can be used as indicators in future forensic investigations.
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Dípteros , Doenças dos Suínos , Animais , Suínos , Calliphoridae , Brasil , Cadáver , LarvaRESUMO
The Brazilian Cerrado is a hotspot of biodiversity conservation and an important global agricultural region. Cultivated pastures under different degradation levels are dominant in the landscape and are being targeted for sustainable agricultural intensification and restoration of native vegetation. In this study, we classified the cultivated pastures of the Brazilian Cerrado according to their potential for natural regeneration, based on field surveys and environmental predictors. We surveyed the native vegetation cover in 186 plots distributed along 93 cultivated pastures. The environmental predictors considered in this study were the proportion of sand in the soil, cation exchange capacity, climate water deficit, pasture age, slope, and pasture vigor index. We then applied the Random Forest regression algorithm to predict and map the cultivated pastures according to their potential for natural regeneration in the 19 Cerrado ecoregions. The potential for natural regeneration was classified into low (< 30% of native plant cover), medium (30-50%), and high (> 50%). Our prediction explained 75% of the data variability. Most of the cultivated pastures presented medium potential for natural regeneration (57%), while 31% and 12% presented high and low potentials, respectively. Cultivated pastures in ecoregions with high mechanization, due to their high water availability and extensive flat terrains, presented low potential for natural regeneration. This first attempt to map the potential for natural regeneration in the cultivated pastures of the Brazilian Cerrado can be used as a proxy for planning low-cost and predictable restoration or environmentally sustainable intensification in this major type of land use found in this biome.
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Conservação dos Recursos Naturais , Monitoramento Ambiental , Brasil , Ecossistema , Biodiversidade , Agricultura , ÁguaRESUMO
BACKGROUND AND AIMS: In eastern Neotropical South America, the Cerrado, a large savanna vegetation, and the Atlantic Forest harbour high biodiversity levels, and their habitats are rather different from each other. The biomes have intrinsic evolutionary relationships, with high lineage exchange that can be attributed, in part, to a large contact zone between them. The genomic study of ecotypes, i.e. populations adapted to divergent habitats, can be a model to study the genomic signatures of ecological divergence. Here, we investigated two ecotypes of the tree Plathymenia reticulata, one from the Cerrado and the other from the Atlantic Forest, which have a hybrid zone in the ecotonal zone of Atlantic Forest-Cerrado. METHODS: The ecotypes were sampled in the two biomes and their ecotone. The evolutionary history of the divergence of the species was analysed with double-digest restriction site-associated DNA sequencing. The genetic structure and the genotypic composition of the hybrid zone were determined. Genotype-association analyses were performed, and the loci under putative selection and their functions were investigated. KEY RESULTS: High divergence between the two ecotypes was found, and only early-generation hybrids were found in the hybrid zone, suggesting a partial reproductive barrier. Ancient introgression between the Cerrado and Atlantic Forest was not detected. The soil and climate were associated with genetic divergence in Plathymenia ecotypes and outlier loci were found to be associated with the stress response, with stomatal and root development and with reproduction. CONCLUSIONS: The high genomic, ecological and morphophysiological divergence between ecotypes, coupled with partial reproductive isolation, indicate that the ecotypes represent two species and should be managed as different evolutionary lineages. We advise that the forest species should be re-evaluated and restated as vulnerable. Our results provide insights into the genomic mechanisms underlying the diversification of species across savanna and forest habitats and the evolutionary forces acting in the species diversification in the Neotropics.
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Pradaria , Árvores , Árvores/genética , Florestas , Ecossistema , Genômica , Genética PopulacionalRESUMO
Clear and data-driven bioregionalizations can provide a framework to test hypotheses and base biodiversity conservation. Here we used occurrence and abundance data in combination with objective analytical methods to propose two bioregionalization schemes for tree species of the Cerrado and the Pantanal in South America. We also evaluated the contribution of three sets of determinants of the occurrence- and abundance-based subregions. We compiled data on tree species composition from 894 local assemblages based on species occurrences, and from 658 local assemblages based on species abundances. We used an unconstrained community-level modelling approach and clustering techniques to identify and map tree subregions for the occurrence and the abundance data sets, separately. Hierarchical clustering analyses were conducted to investigate floristic affinities between the subregions and to map broader floristic regions. We used multinomial logistic regression models, deviance partitioning, and rank-sum tests to assess the main subregion correlates. We identified 18 occurrence- and four abundance-based subregions in the Cerrado-Pantanal. The hierarchical classifications grouped the occurrence-based subregions into nine floristic zones and abundance-based subregions into two broad floristic zones. Variation in subregions were explained mainly by environmental factors and spatial structure in both occurrence and abundance data sets. The occurrence- and abundance-based subregions are complementary approaches to disentangle macroecological patterns and to plan conservation efforts in the Cerrado and the Pantanal. Our findings based on occurrence data revealed more complex and interdigitated boundaries between subregions of tree species than previously reported. The environment, historical stability, and human effects act in a synergetic way on the distribution of the subregions. Finally, the relevance of contemporary environmental factors to the subregion patterns we found alert us to the profound impact global warming may have on the spatial organization of the Cerrado-Pantanal tree flora.
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Different ecosystems evolved and are maintained by fire, with their vegetation hosting species with a wide diversity of persistence strategies allowing them to insulate their body and resprout new branches after fire disturbance. Changes in fire regime are predicted due to climate change, either by promoting more frequent and/or severe fires or by reducing the number of fire events due to the limitation of fuel load. Predicting the future of fire-driven ecosystems is a complex task as species' survival depends on many factors that vary in space and time. Since plants are constantly experiencing new environments as they grow through meristem development, woody plant modularity, modules morpho-physiological aspects and their integration should be considered when investigating species strategies in fire-prone ecosystems: according to their position and their tissue composition, plants' modules experience fire differently and will contribute differently to other modules and the whole plant survival, with consequences cascading over the overall vegetation structure. Growth modules may hold the key to understanding how fast plants can get protected from fire, ultimately helping us to predict which species will persist across changing fire regimes. We present an empirical example showing how different fire-return intervals translate into distinct pressures on the timing, protection and location of modules, and discuss how these can translate into modifications in the vegetation structure due to climate change.
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Nutrient allocation is central to understanding plant ecological strategies and forest roles in biogeochemical cycles. Thought to be mainly driven by environmental conditions, nutrient allocation to woody organs, especially to living tissues, is poorly understood. To examine the role of differences in living tissues (sapwood, SW, vs inner bark, IB), organs, ecological strategies, and environmental conditions in driving nutrient allocation and scaling in woody plants, we quantified nitrogen and phosphorus in main stems and coarse roots of 45 species from three tropical ecosystems with contrasting precipitation, fire regime, and soil nutrients. Nutrient concentration variation was mostly explained by differences between IB and SW, followed by differences between species and, in the case of phosphorus, soil nutrient availability. IB nutrient concentrations were four times those of SW, with root tissues having slightly higher concentrations than stem tissues. Scaling between IB and SW, and between stems and roots, was generally isometric. In cross-sections, IB contributed half of total nutrients in roots and a third in stems. Our results highlight the important role of IB and SW for nutrient storage, the coordination in nutrient allocation across tissues and organs, and the need to differentiate between IB and SW to understand plant nutrient allocation.
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Ecossistema , Nitrogênio , Fósforo , Casca de Planta , Folhas de Planta , Árvores , Solo , Raízes de Plantas , Caules de PlantaRESUMO
Fatal poisonings with diazinon may occur both accidentally or intentionally in suicide cases. Forensic entomotoxicology can aid in understanding these deaths by detecting and analyzing the interference of toxic substances in the biology of necrophagous insects. Hence, this study sought to evaluate diazinon's effect on the composition and succession of calliphorid species in the tropical savannas of the Amazon. Nine rabbit carcasses were divided into three groups: one control and two diazinon treatments (100 mg/kg and 300 mg/kg); each group had three replicates. Three fragments of the Amazon tropical savanna were selected for the experiments. Daily collections of adult and immature calliphorids were performed. Five decomposition stages were observed: fresh, bloated, active decay co-occurring, advanced decay, and dry. Eight species of Calliphoridae were identified among the collected adults: Chloroprocta idioidea (0.1%), Chrysomya albiceps (58.3%), Chrysomya megacephala (14.2%), Chrysomya putoria (2.6%), Cochliomyia hominivorax (1.3%), Cochliomyia macellaria (0.5%), Lucilia eximia (19.8%), and Paralucilia paraensis (3.3%). The adult specimens in the control group with the highest abundance were observed only from the advanced decay stage onward. In the dry stage, abundance was higher in control than in treated carcasses. From the sampled 941 Calliphorid immatures, three species were identified: C. albiceps (76,3%), C. putoria (1%), and L. eximia (22,7). The number of immatures was higher in control than in treated carcasses. Therefore, diazinon interferes with the putrefaction timeframe in carcasses, slowing the decomposition stages and affecting their colonization by immature forms of Calliphoridae.
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Calliphoridae , Dípteros , Animais , Coelhos , Diazinon , Organofosfatos , CadáverRESUMO
Deforestation accounts for the majority of greenhouse gas emissions in developing countries. In Brazil, deforestation represents ~ 70% of the nation's greenhouse gas emissions. Among the main deforested vegetation, Cerrado (Brazilian savanna) occupies a prominent position as it is the second biggest biome in Brazil. Despite its importance, there are still few estimates of above and belowground biomass of Cerrado vegetation encompassing its structural and spatial complexity. Also, Cerrado holds a specific biodiversity that is normally undervalued and which is being lost in the fires of agricultural fronts. In this context, this study aimed to verify the relationship of the existing flora biodiversity in a cerrado stricto sensu with its aboveground biomass and carbon stocks. The possibility of a relationship between fine root mass and soil organic carbon content was also verified. The study area presented a total of 67 species and 798 trees (average: 1596 trees ha-1). The mean total aboveground biomass and carbon stocks were 77.08 Mg ha-1 and 38.54 Mg ha-1 respectively. Soil organic carbon stock (0-30 cm) was 8.51 Mg ha-1 whereas fine roots were 1.637 Mg ha-1. Total aboveground biomass presented a highly significant asymptotic relationship with biodiversity demonstrating its importance in reaching high biomass accumulation. A significant relationship between soil organic carbon content and fine root biomass was found making easier belowground biomass estimates.
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Florestas , Gases de Efeito Estufa , Biomassa , Brasil , Solo/química , Carbono/análise , Monitoramento Ambiental , Biodiversidade , ÁrvoresRESUMO
BACKGROUND AND AIMS: Bark allows species to survive fire, protecting their inner tissues and allowing new branches to resprout from aerial buds. Thus, bark production is likely to be selected with aerial bud protection in fire-prone ecosystems. By considering the coexistence of fire-prone and fire-free ecosystems, in addition to the different impacts of flames on different growth forms, in this study we tested whether: (1) species from areas with higher fire frequencies have a faster bark production; (2) bark growth rate differs between trees and shrubs; (3) generalists adjust their bark production according to their environment (fire-prone or fire-free ecosystems); and (4) fast bark production results in better aerial bud protection. METHODS: We sampled two different types of forests and savannas in the Cerrado and registered every woody individual with height between 1.5 and 3 m tall (directly exposed to the flames). For the 123 species registered, we sampled three different individuals in each vegetation type where the species occurred to assess their bark production and aerial bud protection. We then checked, for each species, their preferred habitat (savanna and forest specialists or generalists) and their predominant growth form. KEY RESULTS: A minimal threshold of 0.13 mm per growth unit of bark production differentiated woody communities from savannas and forests. Shrubs and trees did not differ in terms of bark growth rate, despite being exposed to the flames in a different manner. Generalist species in savannas were able to produce bark above the threshold. However, when these species were in forests they produced bark below the threshold. Finally, a higher bark growth rate accounted for a better aerial bud protection. CONCLUSIONS: Generalist species are likely to be capable of displaying plasticity in their bark production, which could be important for their success in contrasting ecosystems. The relationship between aerial bud protection and bark growth rate suggests that bark production plays an important role in protecting the dormant buds, in addition to being selected in fire-prone ecosystems.
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Ecossistema , Incêndios , Pradaria , Casca de Planta , Florestas , ÁrvoresRESUMO
The Cerrado region comprises the world's most biodiverse savanna and the largest cultivated pastures for cattle in Brazil. Forty percent of these pastures are unproductive or degraded, with bare soil and native vegetation increasingly replacing exotic forage grasses. This study sought to investigate the regeneration of native vegetation in the pastures of the Cerrado and to evaluate the contribution of biophysical, land management, and landscape attributes to this process. Across the Cerrado, we analyzed pasture plant communities and the attributes of pasture management intensification, fire events, landscape native vegetation cover, and climate and soil types of 93 active pastures and 15 abandoned pastures. For the abandoned pastures, time since abandonment was an additional variable. On actively cultivated pastures, savanna regeneration varied from 0 to 70%, with a diversity of herbs and woody species. Pasture management was the main predictor of savanna regeneration on cultivated pastures. On abandoned pastures, time since abandonment was the main predictor. Exotic grass cover had a strong negative relationship with savanna regeneration and they were present even in pastures abandoned for 44 years. Our study reveals the potential of natural regeneration of the Cerrado and its particular predictors. The occurrence of pastures with high natural regeneration indicates that national policies can promote native vegetation restoration and silvopastoral systems with predictable, low cost implementation.
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Ecossistema , Pradaria , Animais , Bovinos , Florestas , Biodiversidade , Solo , Poaceae , BrasilRESUMO
Ants represent one of the most diverse and ecologically important group of insects in tropical ecosystems, including in highly threatened ones such as the Brazilian Cerrado. Yet, a detailed understanding of the species diversity and composition of local Cerrado ant assemblages is lacking in many cases. Here we present the results of a comprehensive ant inventory performed within a region of the Cerrado (in São Paulo state) where most of the original vegetation has already been lost and where few conservation units exist. We performed consecutive surveys of the ant fauna that forage on the ground in replicated plots established in open savanna (campo sujo), dense savanna (cerrado sensu stricto), and forest (cerradão). Our surveys, with an estimated sample coverage of 99.4%, revealed a total of 219 species of ants from 60 genera, of which 36.1% were found in all the three vegetation types and 29.7% in just one. Rarefied species richness did not differ between vegetation types, but species composition differed markedly, especially between the two savannas in one hand and the forest in the other. Several species (60.1% of the 128 species analyzed) were significant "indicator" species due to their strong association with a given vegetation type. Overall, our findings reinforce the idea that habitat heterogeneity enhances ant diversity and that the mosaic of vegetation types that characterizes the Cerrado biome is one of the main factors explaining the elevated number of species that can be found at relatively small scales.
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Formigas , Ecossistema , Animais , Brasil , Florestas , InsetosRESUMO
Foi realizada análise da documentação de animais silvestres recebidos pelo Cetras/IEF de Patos de Minas, MG, durante o ano de 2020, obtendo-se dados da origem dos animais, dos índices de soltura e óbito, da permanência em cativeiro e de condições clínicas na época do recebimento. No período foram recebidos 1.306 animais, sendo 86,9% de aves. A forma de recebimento mais comum foi apreensão por autoridade competente (36,1%), seguida de entrega voluntária (33,2%) e recolhimento em zona urbana/rural (30,8%). Do total, 44,3% dos animais foram reintroduzidos, 39% vieram a óbito, 10% permaneceram no Cetras até o fim do período analisado e 6,7% foram destinados a outras instituições. Animais feridos e filhotes apresentaram taxa de mortalidade de aproximadamente 50%. Observa-se que a entrega voluntária tem crescido, praticamente equiparando-se às apreensões. A taxa de reintrodução é considerada satisfatória em relação à de instituições semelhantes.(AU)
An analysis of the documentation of wild animals received by Cetras/IEF from Patos de Minas, MG, Brazil, during the year 2020 was carried out, obtaining data on the origin of animals, release and death rates, permanence in captivity and data on clinical conditions at the arrival. During the period, 1,306 animals were received, 86.9% of which were birds. The most common form of admission was apprehension by competent authority (36.1%), followed by voluntary delivery (33.2%) and collection. in urban/rural areas (30.8%). Of the total, 44.3% animals were reintroduced, 39% died, 10% remained at Cetras until the end of the period and 6.7% were destined to other institutions. Injured animals and offspring had a mortality rate of approximately 50%. It is observed that the voluntary delivery has increased and almost equaled the apprehensions. The reintroduction rate is considered satisfactory in relation to similar institutions.(AU)
Se realizó un análisis de la documentación de animales silvestres recibidos por el Cetras/IEF de Patos de Minas, MG, Brasil, durante el año 2020, obteniendo datos sobre el origen de los animales, tasas de liberación y muerte, permanencia en cautiverio y datos sobre condiciones clínicas al ingreso. Durante ese período se recibieron 1.306 animales, de los cuales el 86,9% eran aves. La forma de ingreso más común fue aprehensión por autoridad competente (36,1%), seguida de entrega voluntaria (33,2%) y recogida en zona urbana/rural (30,8%). Del total, 44,3% hasta el final del período analizado y 6,7% fueron destinados a otras instituciones. animales fueron reintroducidos, 39% murieron, 10% permanecieron en el Cetras Los animales heridos y jóvenes presentaron tasa de mortalidad de aproximadamente 50%. Se observa que la entrega voluntaria ha crecido y es casi equivalente a las aprehensiones. La tasa de reintroducción se considera satisfactoria comparada a instituciones semejantes.(AU)
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Animais , Bem-Estar do Animal , Animais Selvagens , Brasil , Conservação dos Recursos Naturais , PradariaRESUMO
Abstract Tropical grasslands have been systematically neglected worldwide in maps, conservation policies, and ecological studies. After eradicating invasive pine trees from a Cerrado reserve in southeastern Brazil, an unprecedented grassy ecosystem arose in recent satellite images. In the field, we confirmed the first record of wet grasslands with termite mounds - locally named campo com murundus ˗ beyond 21°S in the São Paulo state. Besides reporting this occurrence, we sampled the two plant communities forming this peculiar vegetation type (the mounds and the waterlogged matrix around them) to investigate if they are floristically and functionally distinct. We also explored how these two communities relate to those of the surrounding open vegetation types (savanna, dry and wet grassland). Woody plants were recorded on the mounds but not in the matrix, although the two communities share some ground layer species. Compared to the adjacent vegetation types, the mounds were floristically distinct and functionally more balanced in growth forms, dispersal syndrome, and tolerance to waterlogging. We hope this borderline record of campo com murundus can stimulate the search for other unnoticed remnants out of their known occurrence region, triggering efforts for their conservation and studies to improve comprehension of these iconic ecosystems.
Resumo Os campos naturais tropicais têm sido sistematicamente negligenciados em todo o planeta, seja nos mapas, nas políticas de conservação ou em estudos ecológicos. Após controle da invasão por Pinus em unidade de conservação do Cerrado no sudeste do Brasil, um ecossistema graminoso sem registro regional surgiu nas imagens de satélite recentes. Observação em campo resultou no primeiro registro de campo com murundus em latitude superior a 21°S, no estado de São Paulo. Além de relatar essa ocorrência, amostramos as duas comunidades vegetais que formam esse tipo de vegetação peculiar (ocorrendo sobre os murundus e na matriz alagadiça ao redor deles) para investigar se são florística e funcionalmente distintas. Também exploramos como essas duas comunidades estão relacionadas com os tipos de vegetação aberta circundantes (savana, campo seco e campo úmido). Plantas lenhosas foram registradas nos murundus, mas não na matriz, embora as duas comunidades compartilhem algumas espécies do estrato rasteiro. Em comparação com os outros tipos de vegetação adjacentes, os murundus se mostraram floristicamente distintos e funcionalmente mais equilibrados em relação às formas de crescimento, síndrome de dispersão e tolerância ao encharcamento. Esperamos que esse registro limítrofe de campo com murundus possa estimular a busca por outros remanescentes despercebidos fora da região de ocorrência já conhecida, desencadeando esforços para sua conservação e estudos que possam melhorar a compreensão desses ecossistemas icônicos.