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1.
J Environ Manage ; 355: 120473, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38430884

RESUMO

Brazil's major beef production occurs in the Cerrado, predominantly as extensive pastures that covers ∼50 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 ∼1830 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 ∼12% 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.


Assuntos
Ecossistema , Gases de Efeito Estufa , Animais , Bovinos , Solo , Gases de Efeito Estufa/análise , Brasil , Gado , Pradaria , Carbono/análise , Agricultura
2.
Environ Sci Pollut Res Int ; 31(14): 20925-20940, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38379047

RESUMO

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.


Assuntos
Mercúrio , Poluentes Químicos da Água , Mercúrio/análise , Brasil , Solo , Poluentes Químicos da Água/análise , Cadeia Alimentar , Monitoramento Ambiental
3.
J Med Entomol ; 60(6): 1297-1304, 2023 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-37769212

RESUMO

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.


Assuntos
Dípteros , Doenças dos Suínos , Animais , Suínos , Calliphoridae , Brasil , Cadáver , Larva
4.
Trop Med Infect Dis ; 7(12)2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36548701

RESUMO

The hand-net is the standard method for capturing mosquitoes with sylvatic diurnal activity in disease outbreaks in Brazil. However, occupational risks and biases related to the collectors' abilities and attractiveness are important limitations. In this study, we compared hand-nets with automatic traps (CDC) associated to CO2 and BG-Lure® in the Vassununga State Park, a Brazilian Savanna protection area. The collections carried out over 27 days on the ground and the forest canopy. A total of 1555 mosquitoes were obtained in 20 taxa. The diversity index ranged between 1.12 and 1.79 and the dominance index from 0.22 to 0.40. The dominant species on the ground was Aedes scapularis (46.0%), and in the canopy, Hg. janthinomys/capricornii (31.9%). Haemagogus leucocelaenus was rare (n = 2). The hand-net resulted in the greatest diversity and abundance of species in both strata, followed by the traps associated with CO2. A low degree of similarity was observed between the hand-net on the ground compared to the other capture methods. The use of BG-Lure® alone resulted in a low number of specimens. In conclusion, the hand-net is still the method of choice for collecting arbovirus vectors in the diurnal period, especially yellow fever vectors.

5.
Int J Mol Sci ; 23(7)2022 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-35408775

RESUMO

Cerrado has many compounds that have been used as biopesticides, herbicides, medicines, and others due to their highly toxic potential. Thus, this review aims to present information about the toxicity of Cerrado plants. For this purpose, a review was performed using PubMed, Science Direct, and Web Of Science databases. After applying exclusion criteria, 187 articles published in the last 20 years were selected and analyzed. Detailed information about the extract preparation, part of the plant used, dose/concentration tested, model system, and employed assay was provided for different toxic activities described in the literature, namely cytotoxic, genotoxic, mutagenic, antibacterial, antifungal, antiviral, insecticidal, antiparasitic, and molluscicidal activities. In addition, the steps to execute research on plant toxicity and the more common methods employed were discussed. This review synthesized and organized the available research on the toxic effects of Cerrado plants, which could contribute to the future design of new environmentally safe products.


Assuntos
Anti-Infecciosos , Plantas Medicinais , Antifúngicos , Brasil , Medicina Tradicional , Extratos Vegetais/efeitos adversos , Plantas Medicinais/efeitos adversos
6.
Biota Neotrop. (Online, Ed. ingl.) ; 22(2): e20211318, Mar 31, 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1403616

RESUMO

Abstract: Cerrado remnants can hold an important diversity of plant species of environmental and ecological relevance. We presented a checklist of vascular plants based on 12 years of inventory carried out in 36 plots (10 m x 2 m; 0.18 ha in total) and during unsystematic walks in a remnant area of cerrado sensu stricto located at Itirapina municipality, state of São Paulo, southeastern Brazil. The list comprised 195 plant species, corresponding to 54 families and 131 genera. The richest families were Fabaceae (25 species), Asteraceae (16), Myrtaceae (16), Rubiaceae (11), Bignoniaceae and Malpighiaceae (10 each), Melastomataceae (9), and Erythroxylaceae, Sapindaceae and Annonaceae (6). Predominant life forms included shrubs and trees, with 68% of the species, followed by lianas with 12%, sub-shrub and herbs with 10% each. Bees were the dominant pollinators (67,5%) and the majority of species had seeds dispersed by animals (56.8%), mostly by birds, followed by wind (33.3%) and self-dispersed (11.2%). More than 60% of the total species were classified as "typical" Cerrado species. Bowdichia virgilioides was the only species classified as Near Threatened (NT) and 157 were regarded as Data Deficient (DD). Our dataset provides floristic, structural, and ecological information for one of the targeted areas for Cerrado survey at São Paulo state, contributing to the understanding of diversity patterns and future conservation and restoration actions in this threatened hotspot.


Resumo: Apresentamos uma lista de verificação de plantas vasculares baseada em 12 anos de inventário realizado em 36 parcelas (10 m x 2 m; 0,18 ha no total) e caminhadas assistemáticas em uma área remanescente de cerrado sensu stricto localizada em Itirapina, município do estado de São Paulo, sudeste do Brasil. A lista é composta por 195 espécies de plantas, correspondendo a 54 famílias e 131 gêneros. As famílias mais ricas foram Fabaceae (25 espécies), Asteraceae (16), Myrtaceae (16), Rubiaceae (11), Bignoniaceae e Malpighiaceae (10 cada), Melastomataceae (9) e Erythroxylaceae, Sapindaceae e Annonaceae (6). As formas de vida predominantes incluíram arbustos e árvores (33,7% das espécies), seguidas por lianas (12%), arbustos e ervas (10%). As abelhas foram os polinizadores dominantes (67,5%) e o principal modo de dispersão foi a zoocoria (56,8%), representada principalmente por pássaros, seguida por vento (33.3 %) e auto (11.2 %). Mais de 60% das espécies encontradas foram classificadas como espécies "típicas" de Cerrado. Bowdichia virgilioides foi a única espécie pertencente a uma categoria de ameaça "Quase Ameaçada (NT)", sendo 157 delas classificadas na categoria "Deficiente de Dados (DD)". Nosso conjunto de dados fornece informações florísticas, estruturais e ecológicas para uma das áreas-alvo do levantamento do Cerrado no estado de São Paulo, sudeste do Brasil, contribuindo para a compreensão dos padrões de diversidade e futuras ações de conservação neste hotspot ameaçado.

7.
Sci Total Environ ; 807(Pt 3): 150998, 2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-34656576

RESUMO

The Cerrado biome covers approximately 20% of Brazil and it is crucial for the Water, Food, Energy, and Ecosystems (WFEE) nexus. Thus, in recent years, large areas of the undisturbed Cerrado have been converted into farmland. In this biome, according to the Brazilian Forest Code, farmers need to keep 20% of native vegetation (Legal Reserves - LRs). By exploring combined and isolated impacts of different scenarios of LR and Protected area (PA) arrangements, this study evaluated the importance of complementarity between LR compliance and the amount of PAs (including Conservation Units - CUs and Indigenous Lands - ILs) to reduce deforestation and conserve native vegetation in the Cerrado. Seven scenarios were investigated: a scenario that considers the current PA and the LR values foreseen in the Native Vegetation Protection Law - NVPL; three scenarios focused on production; and three focused on conservation. Considering the trend of the current scenario, the estimated loss of native vegetation will be 30% (30.6 million ha) by 2070. According to the model simulations, for two periods (2050 and 2070), the LR Elimination scenario (LRE) would cause a greater loss of native vegetation than the PA Elimination (PAE), and as expected, the exclusion of both (PALRE) would provide a greater loss of native vegetation. Native vegetation is concentrated mainly on agricultural properties. Taking our conservation-oriented scenarios as an example of conservation strategies, if there were no financial, practical, political, social or personal constraints, there is no doubt that the CPALRI scenario (Creation of Protected Areas and Legal Reserve Increase) is the best trajectory for conserving biodiversity. Therefore, private properties, through LRs, are essential for efficient planning of land use/cover as they ensure security in the WFEE nexus. The resulting projected scenarios are important to help decision makers in territorial planning and how to arbitrate territorial demands aiming at the rational use of the natural resources of the Cerrado.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Brasil , Conservação dos Recursos Naturais/legislação & jurisprudência
8.
Neotrop Entomol ; 50(5): 748-758, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34283412

RESUMO

Males of euglossine bees, also known as orchid bees, are attracted to aromatic compounds and this feature has been exploited to collect them. Here we sampled orchid bee males using a rapid passive method in a Neotropical savanna ecosystem in Rio Preto State Park (PERP), southeastern Brazil. The sampling protocol consisted of 5-day surveys using scent traps at the beginning and end of the rainy seasons. PERP is inserted in a Brazilian savanna characterized by a mosaic of vegetation types, and elevational gradients. We also analyzed whether the habitat complexity and elevational gradients influence the richness and abundance of these bees. We collected a total of 996 individuals belonging to 14 species and four genera (Eufriesea Cockerell 1908, Euglossa Latreille 1802, Eulaema Lepeletier 1841, and Exaerete Hoffmannsegg 1817). Comparing our results with previous sampling protocols at PERP, higher abundance and richness were observed using traps than insect nets to survey these bees. In addition, the orchid bee fauna in PERP was successfully assessed by our rapid passive protocol, showing that this protocol seems to be useful for collecting orchid bees in open vegetation environments. We observed that the abundance of bees was lower at higher elevations, and both abundance and richness increased in more complex habitat. This may be due to the characteristics of Brazilian savannas where the lower elevations have higher habitat complexity, with more places for nest construction and resources for feeding and nesting.


Assuntos
Abelhas/classificação , Pradaria , Altitude , Animais , Brasil , Masculino , Feromônios , Estações do Ano
9.
J Ethnobiol Ethnomed ; 17(1): 16, 2021 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-33752732

RESUMO

BACKGROUND: Copernicia prunifera belongs to the Arecaceae family, and its production chain includes a set of economic activities based on the use of the stipe, petiole, fiber, fruits, roots, and leaves from which carnaúba wax is extracted, an economically valuable resource in the region. This study aimed to evaluate the uses, management, and perception of the species by local extractors. METHODS: Two communities were studied, Bem Quer, where 15 extractors of carnaúba leaves were interviewed, and Cana, where 21 extractors considered specialists were interviewed, totaling a sample of 36 interviewees. Interviewees were asked questions about uses, ways of handling, and perception of morphological variation in the carnaúba leaves. The number of leaves extracted and the income obtained from the sale of leaves were estimated from interviews and notes that each leader of extractors held during the year of the research and previous years, as well as direct observations made by researchers in the communities which recollection area of straw hold about 80 thousand individuals of C. prunifera. A regression analysis was used to explore the relationships between social variables (age, time in extractive activity, and income obtained from extraction) with the number of leaves exploited. RESULTS: The leaf was indicated as the most used part, from which an important powder is extracted for the production of wax. In addition, the leaf was also indicated to be used for fertilization and construction. The relationship between the socioeconomic variables, income from extraction, and the number of leaves extracted (in thousands) was significant (R2 = 0.73 and p < 0.001). However, the other variables analyzed in this study, such as the time spent extracting leaves and the years of residence in the community (R2 = 0.03 and p > 0.05); the number of leaves extracted and interviewee age (R2= 0.05 and p > 0.05); and the number of leaves extracted and extraction time (R2 = 0.04 and p > 0.05) did not indicate a relationship. CONCLUSION: Local extractors observed that new leaves have the highest sales value, as they have the highest production of powder. In addition, economic factor is the preponderant force that directs the management strategies of native species. For this species, however, morphological and genetic studies are needed for further clarification.


Assuntos
Arecaceae , Ceras , Brasil , Humanos , Folhas de Planta , População Rural , Ceras/economia
10.
Front Microbiol ; 12: 647920, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33767686

RESUMO

Inonotus rickii (Pat.) Reid (Agaricomycetes: Hymenochaetaceae) is a poroid fungus characterized by the expressive production of chlamydospores, in vivo and in vitro, especially during its anamorphic stage. The species plays important ecological roles, standing out as a phytopathogen, affecting several species of ornamental and wild trees, mainly in tropical and subtropical regions. The infected trees develop canker and white rot of the wood, showing symptoms of reduced vegetative vigor and decline of leaves and branches which causes death in some cases. The first record of I. rickii for the Cerrado biome (Brazilian Savanna) and the first record as causal agent of canker in Schinus molle L. in Brazil is reported here. In addition, we present a checklist of its worldwide geographical distribution and known hosts, from an extensive bibliographic search in Google Scholar, SciELO, Scopus, and Web of Science databases. The species is widespread in tropical and subtropical zones; common in the American continent, especially in Central and South America and the Mediterranean region, and rare in temperate zones. We found specimens growing in both living and dead hosts, totalizing 70 species of hosts, distributed in 43 genera and 22 families. Of these, Acer negundo L. (10.5%), Celtis australis L. (6.5%), and Platanus acerifolia (Aiton) Willd. (4.8%), and the Fabaceae (30%), Fagaceae (10%), and Sapindaceae (8.6%) families were the most frequent. We present morphological descriptions and illustrations, as well as the growth characteristics in culture medium. Our study expands the known geographical distribution of I. rickii, including the Cerrado biome, as well as its structural, physiological characteristics, and its hosts.

11.
J Environ Manage ; 275: 111243, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32841792

RESUMO

In recent years, the Cerrado deforestation has increased considerably, reaching rates higher than in the Amazonian realm. Although the effects of deforestation are well known, the understanding of its drives at regional levels is incipient. Most studies consider that a driver influences deforestation likewise in all regions. However, deforestation has a strong spatial structure that can lead drivers to vary their influence on deforestation in different regions. Here, we evaluated the spatial variability in the relationship between the recent Cerrado deforestation and socioeconomic, environmental, and structural drivers at a regional scale. We used a geographically weighted regression (GWR) to assess the spatial variability of predictor variables. We identified regions that respond similarly to the drivers by grouping municipalities, considering their GWR coefficients through hierarchical clustering. The analyses that consider the spatial variability of predictors are more appropriated to assess the causes of recent deforestation. Remnant natural vegetation influenced the recent deforestation in all defined regions. Greater access to rural credit concession was the main driving force of deforestation in the northeast region defined here. Distance to roads increased deforestation in the northeast and north regions, while it inhibited deforestation in the central-east and southeast regions. Rainfall inhibited deforestation in the northeast, north, and southwest regions. Steep slope prevented deforestation mainly in the northeast, north, and southwest regions. Our results highlight that, to effectively reduce Cerrado deforestation, public policies should integrate strategies focusing not only at national and biome levels but also at the regional spatial level.


Assuntos
Ecossistema , Política Pública , Brasil , Conservação dos Recursos Naturais
12.
Environ Entomol ; 49(4): 838-847, 2020 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-32667626

RESUMO

Abiotic factors can affect plant performance and cause stress, which in turn affects plant-herbivore interactions. The Environmental Stress Hypothesis (ESH) predicts that gall-inducing insect diversity will be greater on host plants that grow in stressful habitats. We tested this hypothesis, considering both historical and ecological scales, using the plant Copaifera langsdorffii Desf. (Fabaceae) as a model because it has a wide geographic distribution and is a super-host of gall-inducing insects. According to the ESH, we predicted that 1) on a historical scale, the diversity of gall-inducing insects will be higher in habitats with greater environmental stress and 2) on an ecological scale, gall-inducing insect diversity will be greater on plants that possess greater levels of foliar sclerophylly. We sampled gall-inducing insects on plants of C. langsdorffii in five sites with different levels of water and soil nutrient availability and separated from each other by a distance of up to 470 km. The composition, richness, and abundance of gall-inducing insects varied among study sites. Plants located in more stressful habitats had higher levels of foliar sclerophylly; but richness and abundance of gall-inducing insects were not affected by host plant sclerophylly. Habitat stress was a good predictor of gall-inducing insect diversity on a regional scale, thus corroborating the first prediction of the ESH. No relationship was found between plant sclerophylly and gall-inducing insect diversity within habitats. Therefore, on a local scale, we did not find support for our second prediction related to the ESH.


Assuntos
Insetos , Árvores , Animais , Biodiversidade , Ecossistema , Herbivoria , Solo
13.
Molecules ; 25(12)2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32604974

RESUMO

Environmental conditions influence specialized plant metabolism. However, many studies aiming to understand these modulations have been conducted with model plants and/or under controlled conditions, thus not reflecting the complex interaction between plants and environment. To fully grasp these interactions, we investigated the specialized metabolism and genetic diversity of a native plant in its natural environment. We chose Myrcia bella due to its medicinal interest and occurrence in Brazilian savanna regions with diverse climate and soil conditions. An LC-HRMS-based metabolomics approach was applied to analyze 271 samples harvested across seven regions during the dry and rainy season. Genetic diversity was assessed in a subset of 40 samples using amplified fragment length polymorphism. Meteorological factors including rainfall, temperature, radiation, humidity, and soil nutrient and mineral composition were recorded in each region and correlated with chemical variation through multivariate analysis (MVDA). Marker compounds were selected using a statistically informed molecular network and annotated by dereplication against an in silico database of natural products. The integrated results evidenced different chemotypes, with variation in flavonoid and tannin content mainly linked to soil conditions. Different levels of genetic diversity and distance of populations were found to be correlated with the identified chemotypes. These observations and the proposed analytical workflow contribute to the global understanding of the impact of abiotic factors and genotype on the accumulation of given metabolites and, therefore, could be valuable to guide further medicinal exploration of native species.


Assuntos
Flavonoides/química , Metabolômica/métodos , Myrtaceae/química , Taninos/química , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Cromatografia Líquida , DNA de Plantas/genética , Variação Genética , Pradaria , Myrtaceae/genética , Extratos Vegetais/química
14.
Biosci. j. (Online) ; 36(4): 1335-1352, 01-06-2020. ilus, tab, graf
Artigo em Inglês | LILACS | ID: biblio-1147293

RESUMO

The characterization of wood anatomy and proprieties can provide subsidies for rational use of tree species. Enables, oftentimes, the definition of technological potential of wood - and wood products - through the assessment of quality information and also allows it ́s correct identification, contributing to the timber production chain. The objective of this study was to contribute to the knowledge about wood properties of the Cerrado biome (Brazilian savanna) species trough the anatomical characterization and determination of density profile. Twenty trees species belonging to thirteen families occurring in Pirenópolis, Goiás and Brasília, Federal District, Brazil, was selected and radial samples were removed from the tree trunks at the DBH (1.30 m) in a non-destructive way using an incremental probe and a motorized extractor. The qualitative and quantitative anatomical parameters of vessels and fibers and the wood density were determined in the collected samples. Species presented fibers with mean values between 900.5 and 2052.9 µm for the length; 18.1 and 27.7 µm for the diameter; and 4.4 to 9.4 µm for the wall thickness. The species presented a variation in the vessel dimensions from 29.2 to 155.6 µm for the diameter; 17.7 to 32.5% for occupied area; and 2.6 to 165 to vessels.mm-2. The apparent density presented mean values between 0.36 and 1.21 g cm-3. The specie that presented the highest variation of wood density was A. fraxinifolium. According to the radial profiles two patterns of increasing and stable variation in the apparent density of the pith to bark were defined as a function of the wood anatomical characteristics.


A caracterização anatômica e das propriedades da madeira pode auxiliar na tomada de decisão quanto ao uso racional de espécies. Possibilita, muitas vezes, a definição do potencial tecnológico da madeira - e produtos - fornecendo acesso a informações sobre a sua qualidade, além de sua correta identificação, contribuído com a cadeia produtiva madeireira. O objetivo deste estudo foi investigar e caracterizar as propriedades da madeira de espécies arbóreas do Cerrado, através da descrição anatômica e determinação do perfil de densidade. Foram selecionadas 20 espécies pertencentes a treze famílias, na cidade de Pirenópolis, Goiás e Brasília, Distrito Federal, Brasil, e amostras radiais foram retiradas dos troncos das árvores no DAP (1,30 m) de forma não destrutiva, utilizando-se uma sonda de incremento e um extrator motorizado. Nas amostras coletadas, foram determinados os parâmetros anatômicos qualitativos e quantitativos dos vasos e das fibras e a densidade aparente da madeira. As espécies apresentaram fibras com valores médios entre 900,5 a 2052,9 µm para o comprimento; 18,1 a 27,7 µm para o diâmetro e 4,4 a 9,4 µm para a espessura da parede; e variação nas dimensões dos vasos de 29,2 a 155,6 µm para o diâmetro; 17,7 a 32,5% para área ocupada; e 2,6 a 165 vasos.mm-2 para a frequencia dos vasos. A densidade aparente apresentou valores médios entre 0,36 e 1,21 g cm-3. A espécie que apresentou a maior variação de densidade de madeira foi A. fraxinifolium. De acordo com os perfis radiais, dois padrões de variação crescente e estável na densidade aparente, da medula para casca, foram definidos como uma função das características anatômicas.


Assuntos
Madeira , Pradaria , Desenvolvimento Sustentável
15.
Environ Monit Assess ; 192(6): 378, 2020 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-32424709

RESUMO

The exploitation of forest resources, especially non-timber forest products, has effects on different biological levels, from the biochemical level of an organism to the ecosystem level. The present study addresses the effects of different management strategies (protected area, managed area, and an area where the species is cultivated in agroforestry systems) in reproductive phenology, fruit features, and phytochemical profiles of Dimorphandra gardneriana (Leguminosae), a tree species, pioneer, and socioeconomically important plant of the Brazilian Savanna. Its fruits are exploited by extractivist communities to obtain rutin and quercetin, which are internationally traded bioflavonoids (two of the ten most exported phytochemicals in Brazil). The results showed that the effects on these parameters were characterized as positive, increasing according to the level of exploitation. The agroforestry system had higher yields of flavonoids of economic interest, viable fruits and seeds, followed by the management area and the protected area. Finally, knowledge about the planting effects on fava d'anta fruit production can be a great ally for effectively managing forest resources. A varied system of exploitation implies greater and more stable economic returns for extractive communities, favoring the conservation of the species in protected areas.


Assuntos
Ecossistema , Fabaceae , Flavonoides , Brasil , Conservação dos Recursos Naturais , Monitoramento Ambiental , Árvores , Clima Tropical
16.
Sci Total Environ ; 730: 139039, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32388377

RESUMO

Phenological studies of Brazilian savanna vegetation have described a generalized phenological pattern for all species, mainly based on rainfall and temperature. Few studies have considered wind as an explanatory factor; abiotic factors may impact differently on phenophases, and one phenophase may influence the performance of another. Thus, we aim to describe the phenological patterns of five anemocoric plant species (Aspidosperma tomentosum, Dalbergia miscolobium, Kielmeyera coriacea, Peixotoa tomentosa and Qualea multiflora) in the face of different climatic conditions, mainly evaluating the effects of wind on the ripe diaspore. We addressed three main questions: (1) What is the phenological behavior of each of these five anemocoric species in a seasonal environment? (2) Which climatic variables best explain each phenophase? (3) Does the dispersal of ripe diaspores peak shortly after deciduousness? We found that (i) our focal species showed similar phenological patterns, except for the floral bud and flower phenophases of two species (A. tomentosum and P. tomentosa), and the young fruit phase; (ii) each abiotic variable has a specific level of influence for each phenophase, but the most important variables were rainfall and wind speed; and (iii) the dispersal peak of ripe diaspores occurred shortly after deciduousness, and when plants had fewer leaves. We conclude that the phenological patterns of these five anemocoric plants are similar, but that the patterns observed are not necessarily those described for Cerrado species. Additionally, we found that wind is an important factor in the expression of specific phenophases, and that the performance of some phenological events can be influenced by others, especially diaspore dispersal.


Assuntos
Plantas , Brasil , Flores , Frutas , Estações do Ano , Temperatura
17.
Preprint em Inglês | SciELO Preprints | ID: pps-597

RESUMO

As a cosmopolitan family, Ganodermataceae has as distinctive characteristic the presence of double-walled basidiospore: the inner wall thick and ornamented, and the outer wall smooth. Even with the increasing interest in this family, the species are still poorly known in different regions of the brazilian territory, such as in the central Brazil. This study presents new distribution remarks of Ganodermataceae species in different sites of the biome Cerrado, in the Midwest region. We found 23 specimens from five species which are distributed into three genera, Amauroderma, Foraminispora and Ganoderma. From those species, one is a new record for the Cerrado (A. exile), four are new for the State of Goiás A. exile, F. rugosa, G. multiplicatum and G. stipitatum and one for the Distrito Federal (G. stipitatum). Amauroderma aurantiacum is rediscovered in Goiás after 88 years. This study contributes to improving the knowledge regarding the geographic distribution of these taxa in Brazil.


Cosmopolita, a família Ganodermataceae tem como característica distintiva a presença de basidiósporos de parede dupla, sendo a interna espessa e ornamentada e a externa lisa. Mesmo com o crescente interesse pela família, as espécies ainda permanecem muito pouco conhecidas em diferentes localidades do território brasileiro, como é o caso do Brasil central. Este trabalho relata novas ocorrências de espécies de Ganodermataceae em diferentes localidades do bioma Cerrado, na região Centro-Oeste. Os espécimes estudados somam 23 exemplares de cinco espécies, distribuídas em três gêneros, Amauroderma, Foraminispora e Ganoderma. Dessas, uma é novo registro para o Cerrado (A. exile), quatro são novas para o estado de Goiás A. exile, F. rugosa, G. multiplicatum e G. stipitatum e uma para o Distrito Federal (G. stipitatum). Amauroderma aurantiacum é novamente registrada para o estado de Goiás após 88 anos. Este trabalho contribui para ampliar o conhecimento da distribuição geográfica das espécies no Brasil.

18.
Neotrop. ichthyol ; 18(2): e190130, 2020. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1135388

RESUMO

Drought can be viewd as a perturbation in running waters and fish are often trapped in isolated pools, where deterioration of water quality may be stressful. We investigated how this extreme condition influences response of oxidative stress biomarkers. The response of the characid Astyanax elachylepis was assessed during the dry and rainy seasons in intermittent and perennial (control) sites in streams from Brazilian savannah (Cerrado). We predicted that the biomarkers would be enhanced in the dry season in intermittent streams only due the environmentally harsh conditions in the few isolated pools that remain filled with water. As predicted, fish from the intermittent stream in the dry season presented higher gill MDA values, indicating greater stress. In the liver, MDA values were higher in the dry season for both intermittent and perennial streams, suggesting a generalized seasonal response. As expected, some antioxidant response enzymes changed in the intermittent sites during the dry season. Therefore, oxidative stress biomarkers vary seasonally, with greater increase in intermittent sites. These evidences contribute for the understanding of the spatio-temporal variation of the fish responses and fish resistance to perturbations by drought in tropical environments.(AU)


A seca pode ser vista como uma perturbação em ambientes aquáticos lóticos e, em alguns casos, os peixes podem ser aprisionados em trechos lênticos (poços), onde a perda da qualidade da água pode causar estresse. Investigamos como esta condição extrema influencia biomarcadores bioquímicos de estresse oxidativo. Para isso, a resposta do caracídeo Astyanax elachylepis foi avaliada durante as estações seca e chuvosa em trechos intermitentes e perenes (controle) de riachos da savana brasileira (Cerrado). Predizemos que os biomarcadores seriam aumentados somente em peixes dos trechos intermitentes durante a estação seca, devido as condições restritivas dos poucos poços isolados que contém água. Como predito, os peixes do riacho intermitente apresentaram altos valores de MDA nas brânquias durante a estação seca, indicando maior estresse oxidativo. No fígado, os valores de MDA foram maiores na estação seca em ambos riachos, intermitente e perene, sugerindo uma resposta sazonal generalizada. Como esperado, algumas enzimas antioxidantes foram alteradas em peixes de trechos intermitentes durante a estação seca. Portanto, os biomarcadores de estresse oxidativo variam sazonalmente e essa variação é maior em trechos intermitentes. Essas evidências contribuem para a compreensão da variação espaço-temporal da resposta dos peixes e da sua resistência às perturbações por seca em ambientes tropicais.(AU)


Assuntos
Animais , Biomarcadores , Estresse Oxidativo , Characidae , Peixes , Estações do Ano , Rios , Antioxidantes
19.
Biota Neotrop. (Online, Ed. ingl.) ; 20(3): e20201015, 2020. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1131940

RESUMO

Abstract: The first case of parasitoidism of a Myrmicinae ant by a sarcophagid fly has been observed in the Brazilian Cerrado. The larva of a Helicobia Coquillet (Sarcophagidae) specimen fed on head tissues of an Atta laevigata Smith, 1858 soldier and an adult male fly emerged from a puparium formed outside the host.


Resumo: O registro do parasitoidismo de uma formiga Myrmecinae por uma mosca Sarcophaginae foi relatado no Cerrado brasileiro. A larva de um exemplar de Helicobia Coquillet (Sarcophagidae) se alimentou dos tecidos da cabeça de um soldado de Atta laevigata Smith, 1858 e um adulto macho emergiu de um pupário que se formou fora do hospedeiro.

20.
Zootaxa ; 4648(1): zootaxa.4648.1.10, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31716966

RESUMO

Esemephe peba sp. nov is described. This newly discovered species represents the first record of Cossyphodini from Brazil. It is also the second species of the genus Esemephe Steiner and differs from the type species in antennal, elytral and aedeagal structure. Descriptions of male and female terminalia are provided, as well as the revised diagnosis and distributional map for Esemephina. Finally, an updated identification key to the World genera of Cossyphodini is proposed.


Assuntos
Besouros , Animais , Brasil , Feminino , Masculino
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