Cerrado soils are acidic and nutrient-poor,with high content of solubilized Al 3+.Plants growing in these conditions may display adaptations to cope with high aluminum concentrations especially during early developmen...Cerrado soils are acidic and nutrient-poor,with high content of solubilized Al 3+.Plants growing in these conditions may display adaptations to cope with high aluminum concentrations especially during early developmental stages.We investigated leaf nutritional status,and photosynthetic and growth characteristics during the initial establishment of Handroanthus impetiginosus(Mart.Ex Dc.)Mattos,a secondary tree species distributed in the Brazilian Cerrado.Our goal was to understand leaf-level traits related to diff erent aluminum concentrations.H.impetiginosus plants were cultivated in four diff erent aluminum sulfate concentrations:0,1,2,and 4 mM Al,for 40 days.We performed analyses of growth,leaf gas exchange,chloroplast pigment content,and leaf mineral nutrients.We observed a linear increase of Al leaf content as a function of Al concentration in the nutrient solution.Plants grown in 1 mM Al showed a remarkable increase of K leaf content,net photosynthesis,stomatal conductance,and transpiration,while in 4 mM Al there were reductions of N,P,and K contents,gas exchange characteristics,and height.H.impetiginosus did not have mechanisms of avoidance,compartmentalization,or resistance to high Al concentrations.Indeed,this species showed a hormetic response,with low Al concentrations stimulating and high Al concentrations inhibiting plant responses.展开更多
In this study,authors analyzed value,production and area used for producing Cerrado’s main agricultural products,and data on the farms located within this biome and registered in CAR up until April 2019,by microregio...In this study,authors analyzed value,production and area used for producing Cerrado’s main agricultural products,and data on the farms located within this biome and registered in CAR up until April 2019,by microregion.The territory considered here comprised all microregions with at least 25%of its area covered by the Cerrado biome.The production,agricultural production,and planted area values used were the averages of the 2015 to 2017 harvests,and are shown in graphs and tables,as are maps of planted areas and groups of main annual crops,semi-perennial and perennial crops.The areas designated for environmental preservation(ADPs)are the result of the sum of permanent preservation areas(APP),legal reserves(RL)and additional vegetation areas within the farms.Authors’study shows that most of Brazilian cotton,eucalyptus for charcoal,orange,sugarcane,maize and soybean are produced in Cerrado,that 28%of Cerrado are ADPs within farms,and that 16%are areas planted with cotton,eucalyptus,orange,sugarcane,maize,soybean,coffee,beans,and potatoes.The territory occupied by agricultural areas and ADPs required by the Brazilian Forest Code shows that agricultural production and environmental preservation do coexist,and gather the maintenance of essential ecosystem services provided by the ADPs together with the development of the country’s relevant agricultural production.展开更多
This work focused on the prediction modeling of Cerrado occurrences in the Atlantic Rainforest predominance in the São Paulo Metropolitan Region (SPMR), the fourth largest urban area, in the city of Guarulhos...This work focused on the prediction modeling of Cerrado occurrences in the Atlantic Rainforest predominance in the São Paulo Metropolitan Region (SPMR), the fourth largest urban area, in the city of Guarulhos, southeastern Brazil. The methodology was based on the selection of records of occurrence of Cerrado in georeferenced databases, thematic maps of geoenvironmental layers, and modeling of the distribution of species through the MaxEnt tool. Besides that, field research confirmed the presence or not of the species in the areas with a high probability of occurrence of Cerrado (≥0.7). As a result, the model observed a great capacity for the prediction of the occurrence of Cerrado in Ecotonal and anthropic regions (AUC = 0.82), revealing important hotspots such as relics from the past or Cerrado enclaves of high biodiversity. The work also points priority areas for the conservation and preservation of this increasingly endangered biome.展开更多
Inner bark extracts of Stryphnodendron adstringens, a leguminous tree species known as Barbatimão, are often incorporated to phytotherapic formulations due to their antimicrobial and healing activities. In ...Inner bark extracts of Stryphnodendron adstringens, a leguminous tree species known as Barbatimão, are often incorporated to phytotherapic formulations due to their antimicrobial and healing activities. In this study, extracts from S. adstringens accessions collected in 12 distinct locations were investigated in order to determine the rates of tannins in inner barks and to validate S. adstringens antibacterial and antifungal effectiveness. Yields of tannins were quantified by colorimetric assay following methodology described in the Brazilian Pharmacopoeia and the antimicrobial activity was determined by microdilution technique proposed by the National Committee for Clinical Laboratory Standards using S. adstringens hydroalcoholic and aqueous extracts and semi-purified fractions. Investigated extracts did not present significant antibacterial activity though aqueous extracts exhibited antifungal effect against both Trichophyton rubrum mutant and clinical strains (MIC 156 μg/mL). A positive correlation between tannin concentration and antifungal activity was observed and the accessions collected in Delfinópolis (MG) were considered elite.展开更多
Potential interactive effects and trade-offs between drivers can regulate species diversity,affecting distributions by several orders of magnitude and distribution.The decomposition ofβ-diversity into turnover and ne...Potential interactive effects and trade-offs between drivers can regulate species diversity,affecting distributions by several orders of magnitude and distribution.The decomposition ofβ-diversity into turnover and nestedness could disentangle community assembly rules and offer the opportunity to encompass the processes that structure the communities and maintain theβ-diversity on the campo rupestre.We evaluatedα-andβ-diversity and species conservation status of rocky outcrop communities in the Parque Nacional da Serra do Cipó,as well as the decomposed component of theβ-diversity index.Due to the isolation characteristics of rocky outcrops,we expect to find high taxonomic turnover among the communities.The study was performed on five quartzitic rocky outcrops divided into two sampling stations.We used field expeditions and plant inventory data of shrubs and herbaceous layers.We recorded 286 angiosperms taxa among rocky outcrops of campo rupestre of Serra do Cipó.The structure andα-diversity showed significant differences among rocky outcrops and an evident oligarchic structure in the plant communities analyzed.Taxonomicβ-diversity showed high turnover with a significant contribution of the turnover component to this index.This pattern reflects the interplay between regional and local scale processes.Therefore,we believe this approach becomes a unified framework,which allows the comparison of diversity patterns and ecological processes in rocky outcrops ecosystems.We highlight the high percentage of not evaluated species for threats and the need to fill this lack.展开更多
The Brazilian Cerrado has been converted to farmland,and there is little evidence that this expansion will decrease,mainly because agriculture is the country's main economic sector.However,the impacts of intense m...The Brazilian Cerrado has been converted to farmland,and there is little evidence that this expansion will decrease,mainly because agriculture is the country's main economic sector.However,the impacts of intense modification of land use and land cover on surface runoff and soil erosion are still poorly un-derstood in this region.Here,we assessed surface runoff and soil loss in a woodland Cerrado area under a former pasture area,which was abandoned and has undergone a natural regeneration process for 7 years(RC).Its results were compared with that found in an undisturbed area of woodland Cerrado(CE),40-month-old eucalyptus(3.0×1.8 m)(EU),and pasture under rotational grazing(PA).The study was conducted on Red Acrisol located in the Brazilian Cerrado.We performed rainfall simulations on a plot of 0.7 m2 and using three constant rainfall intensities of 60,90,and 120 mm h-1 for 1 h.For each rainfall intensity,we carried out four repetitions using different plots in each treatment,i.e.12 plots per treat-ment studied and 48 plots in total.We noted that the soil physical properties were improved in RC and,consequently,water infiltration and soil erosion control;RC presented surface runoff and soil loss different from EU and PA(a=0.05).The macroporosity and soil bulk density affected surface runoff in RC and PA because the RC was used as pasture and is currently regenerating back to the cerrado vegetation.As the rainfall intensity increased,EU became more similar to PA,which showed the highest surface runoff and soil loss.Our findings indicate that natural regeneration processes(pasture to the cerrado vegetation)tend to improve the soil ecosystem services,improving infiltration and reducing surface runoff and soil erosion.展开更多
Fruit residues may contain lactic acid bacteria(LAB)with probiotic properties.This study aimed to isolate,characterize and identify LAB isolated from Brazilian Cerrado fruit residues,as well as to evaluate the safety ...Fruit residues may contain lactic acid bacteria(LAB)with probiotic properties.This study aimed to isolate,characterize and identify LAB isolated from Brazilian Cerrado fruit residues,as well as to evaluate the safety and functionality properties in vitro.Twenty colonies were isolated and characterized.Biochemical and morphological analyses showed 14 LAB isolates,which were identified by sequencing the 16S rRNA gene in Lactiplantibacillus plantarum/pentosus,Lacticaseibacillus casei/paracasei,Pediococcus adicilactici and Weissella cibaria/confusa.Most of the isolates showed susceptibility to antibiotics and none showed hemolytic,gelatinase,coagulase,and DNAse activity.At pH 2,the survival of most strains examined was reduced after 3h exposure-.Four showed a survival rate similar to control,while L.casei/paracasei from guapeva fruit showed a higher rate.11 isolates inhibited the growth of Esherichia coli,Staphylococcus aureus and Salmonella sp.Cluster analysis grouped the isolates according to similarity.The results highlight the specificity of the food matrix,genus,species and strain,however selected LAB strains can be submitted for further investigation of new probiotic strains.展开更多
Knowledge regarding the influence of individual traits on interaction patterns in nature can help understand the topological role of individuals within a network of intrapopulation interactions.We tested hypotheses on...Knowledge regarding the influence of individual traits on interaction patterns in nature can help understand the topological role of individuals within a network of intrapopulation interactions.We tested hypotheses on the relationships between individuals'positions within networks(specialization and centrality)of 4 populations of the mouse opossum Gracilinanus agilis and their traits(i.e.,body length,body condition,tail length relative to body length,sex,reproductive condition,and botfly parasitism)and also seasonal effects in the Brazilian savanna.Individuals with lower body length,better body condition,and relatively shorter tail were more specialized(i.e.,less connected within the network).Individuals were also more specialized and less connected during the warm-wet season.The relationship between individuals'position in the network and body traits,however,was independent of season.We propose that specialization may arise not only as a result of preferred feed-ing strategies by more capable individuals(i.e.,those with better body condition and potentially prone to defend and access high-quality food resources)but alsobecause of morphological constraints.Smaller/younger individuals(consequently with less experience in foraging)and short-tailed individuals(less skilled to explore the vertical strata of the vegetation)would feed only on a subset of the available food resources and consequently become more specialized.Moreover,individuals are more specialized during the warm-wet season because of high competition(population-dense period)and higher ecological opportunities(resource-rich period).Therefore,our study reveals the relevance of individual traits inshaping interactionpatternsandspecialization inpopulations.展开更多
Mountains exhibit a high degree of endemism and diversity,however,quantifying their biodiversity can be challenging.Similar to islands,species isolation in mountainous regions results in comparable patterns of evoluti...Mountains exhibit a high degree of endemism and diversity,however,quantifying their biodiversity can be challenging.Similar to islands,species isolation in mountainous regions results in comparable patterns of evolution and extinction,rendering their biodiversity unique and highly susceptible to anthropogenic threats.The topographic relief in mountains plays a crucial role in creating habitat complexity,which in turn contribute to high plant diversity.Here,we investigated plant diversity in the volcano mountaintop vegetation on the Poços de Caldas Plateau,a region situated in the ecotone between the Atlantic Forest and Cerrado,characterized by natural radiation and significant anthropogenic intervention.We employed an automated approach through the filtering of georeferenced and non-georeferenced data to obtain a list of plant species in the region.Additionally,we statistically investigated the similarity among different high-altitude vegetations belonging to the campos de altitude from the Atlantic Forest and campos rupestres from the Cerrado.The plateau exhibits high plant diversity,including 1,659 specific and infraspecific taxa,especially belonging to Asteraceae and Poaceae.Our analyses suggest that geographical distance is a strong predictor of dissimilarity and that the Poços de Caldas Plateau is more floristically related to the campos rupestres,despite being associated with campos de altitude.The region possesses a unique set of biodiversity,indicating that it may be a distinct formation.Additionally,we hypothesize that Pleistocene events likely influenced the conformation of the current floristic composition in the region through species interchange between the Cerrado and Atlantic Forest.Our study also highlights the few taxa assessed for conservation status and anthropogenic threats that this habitat is facing.展开更多
Although forests play important roles in the hydrological cycle,there is little information that relates the water retention capacity of litter in areas under passive restoration,especially in Cerrado savannas.This st...Although forests play important roles in the hydrological cycle,there is little information that relates the water retention capacity of litter in areas under passive restoration,especially in Cerrado savannas.This study relates litter levels to water holding capacity and effective water retention among forest fragments under different passive restoration stages:46,11,and 8 years to better understand litter hydrological functions in the Cerrado.Water retention capacity and effective water retention capacity of litters(unstructured materials,branches and leaves)in the field were monitored on a monthly basis.Total litter accumulation at 46 years was significantly higher than that of the other succession stages.Unstructured litter mass was significantly higher than that of leaves and branches.The 46-year stage had the highest water holding capacity in the leaf fraction,followed by unstructured material and branches.Although the water holding capacity was lower in the oldest resto-ration,this site showed the highest efficiency under field conditions.The process was quickly reestablished,as the 11-year restoration showed results closer to that for the 46-year stage in comparison to the area at 8 years.Thus,passive restoration plays a key role in soil water mainte-nance due to the influence of litter in Cerrado savannas.Deforestation and the imminent need of restoring degraded sites,highlight the need for further studies focused on bet-ter understanding of the process of forest restoration and its temporal effect on soil water recovery dynamics.展开更多
We identified climatically stable areas of seasonally dry forests (SDFs) from Central Brazil through time and assessed the effectiveness of the current reserves network in representing these climatically stable areas,...We identified climatically stable areas of seasonally dry forests (SDFs) from Central Brazil through time and assessed the effectiveness of the current reserves network in representing these climatically stable areas, as well as areas of high suitability in the present or in the future only. We used an ensemble approach based on several methods for ecological niche modelling (ENMs) to obtain potential distributions 16 SDF’ species for past (last glacial maximum), present, and future (end of XXI century) climate scenarios. We then computed how many current Brazilian reserves matched both stable areas (suitable areas for all time periods), present and future geographical ranges alone for each species, in a multi-level gap analysis. We found range shifts due to climate changes for SDF’ species. Although the future geographical range and stable areas for all analyzed species matched at least with one reserve, many protected areas will lose importance in protecting suitable areas for species in the future. Moreover, the current Brazilian reserves cover only a small amount of their climatically stable areas. However, some reserves will be suitable for many SDF’ species (90%) at the same time, but climatically stable for only half of them. Our findings show that vegetation community from SDFs may persist in Brazilian territories until the end of XXI century, and challenges about long-term conservation of the SDFs may be partially reached with already existing Brazilian reserve network, however the reserves should be connected to permit habitat tracking.展开更多
In this paper we analyze and compare natural regeneration in shrub-tree community in three areas below Pinus caribaea stands and a natural area （cerrado sensu stricto）. We also analyze the influence of biophysical a...In this paper we analyze and compare natural regeneration in shrub-tree community in three areas below Pinus caribaea stands and a natural area （cerrado sensu stricto）. We also analyze the influence of biophysical and environmental variables on the distribution of regenerating shrub-tree species. The areas were analyzed and compared in relation to dispersal syndromes as well, being zoochory and anemochory the prevailing syndroms in the four areas. The sites below P. caribaea show a heterogeneous regen- eration with the number of species ranging from 18 to 42. We analyzed the influence of the biophysical and envi- ronmental variables performing a canonical correspon- dence analyses, being found significant values for variables distance from remnant and basal area. The species Si- paruna guianensis, Miconia albicans, Xylopia aromatica, Sclerolobium paniculatum, Casearia sylvestris and P. caribaea were the most importante ones in the four areas,展开更多
Diverse conservation efforts have been expanding around the globe, even under the stress of increasing agricultural production. A striking example is the supply-chain agreements put upon the Amazon forest which had re...Diverse conservation efforts have been expanding around the globe, even under the stress of increasing agricultural production. A striking example is the supply-chain agreements put upon the Amazon forest which had reduced deforestation by 80% from the early 2000s （27,772 km2） to 2015 （6207 km2）. However, evaluation of these conservation efforts usually focused on the impacts within the Amazon biome only, while the effects that spill over to other areas （e.g., displacement of environmental pressure from one area to another） were rarely considered. Ignoring spillover effects may lead to biased or even wrong conclusions about the effectiveness of these conservation efforts because the hidden cost outside the target area of conservation may offset the achievement within it. It is thus impor- tant to assess the spillover effects of these supply-chain agreements. In this study, we used the two supply-chain agreements （i.e., Soy Moratorium and zero-deforestation beef agree- ment） implemented in the Amazon biome as examples and evaluated their spillover effects to the Cerrado. To achieve a holistic evaluation of the spillover effects, we adopted the telecou- piing framework in our analysis. The application of the telecoupling framework includes the interactions between distant systems and extends the analytical boundaries beyond the sig- natory areas, which fill the gap of previous studies. Our results indicate that the supply-chain agreements have significantly reduced deforestation by half compared to projections within the sending system （i.e., Para State in the Amazon, which exports soybeans and other agricultural products）, but at the cost of increasing deforestation in the spillover system （i.e., a 6.6 time increase in Tocantins State of the Cerrado, where deforestation was affected by interactions between the Amazon and other places）. Our study emphasizes that spillover effects should be considered in the evaluation and planning of conservation efforts, for which the telecoupling framework works as a useful tool to do that systematically.展开更多
A few decades ago we sought the understanding of the functioning of Brazilian ecosystems. During these years, changes in the way land use were influenced primarily by economic issues involving the process of valuation...A few decades ago we sought the understanding of the functioning of Brazilian ecosystems. During these years, changes in the way land use were influenced primarily by economic issues involving the process of valuation of land in different regions. Furthermore, developments in research have provided productive increments that were well characterized in some phases. This paper aims to trace a brief history of the distribution of grassland ecosystems in Brazil and show how it has been the advances in research on forages and pastures in the country, pointing its evolution, transition times and trends. Moreover, it purports to show a perspective of the dynamics of occupation of Brazilian territory by these ecosystems. The information is presented on three occasions, seeking to encourage understanding of where livestock grazing occurs and how the dynamics of occupation of the area was favored by the search. Also, it shows how the research was fundamental for Brazil occupy little arable areas considered, making the country one of the largest producers of cattle in the world.展开更多
Despite the exceptional species richness and endemism,the environmental drivers of plant diversity along old tropical mountains remain underexplored.The respective importance of vegetation types,elevation,slope,and so...Despite the exceptional species richness and endemism,the environmental drivers of plant diversity along old tropical mountains remain underexplored.The respective importance of vegetation types,elevation,slope,and soil to drive diversity across life-forms is poorly addressed.Here,we tested whether environmental variables drove local and regional plant diversity along an old tropical mountain according to the three main life-forms:graminoids,herbaceous and woody species.We sampled all Angiosperm species on 180 plots across five elevations,at the tropical old-mountain region of Serra do Cipó,South-eastern Brazil.We assessed soil,slope,and vegetation types,and calculated richness and beta-diversity,applying generalized least square models,linear mixed-models and partial Mantel tests to test for relationships.Richness of graminoids and herbaceous species increased with greater elevation and more nutrient-impoverished soils,while woody richness showed the inverse pattern.Beta-diversity was primarily driven by species turnover,correlated with elevation and soil and higher in less dominant vegetation types,with unique species.Despite the limited elevational range in these old mountains,it still played an important role in filtering woody species,while fostering graminoid and herbaceous species.Conservation and restoration actions need to foster the high regional diversity supported by the old mountain heterogeneous landscape and the diversity of life-forms,especially the dominant and highly diverse grassy component.展开更多
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 pr...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.展开更多
The little layer of tree plantations provides primary nutrients for uptake,buff ers changes in soil moisture,and provides habitat and substrate to soil epigeic fauna.However,this layer in eucalypt plantations is often...The little layer of tree plantations provides primary nutrients for uptake,buff ers changes in soil moisture,and provides habitat and substrate to soil epigeic fauna.However,this layer in eucalypt plantations is often removed to reduce fuel load during the fi re season in the Brazilian savanna(Cerrado).Therefore,it is necessary to quantify the eff ects of changes in litter dynamics on the function of these plantations,on key nutrient cycling processes and on epigeic fauna diversity and abundance.In two adjacent stands(one juvenile and one mature),the consequences of two years of litter removal were quantifi ed as monthly litterfall,leaf and fi ne wood litter decomposition,epigeic fauna abundance and diversity,soil biogeochemical variables,and tree diameter and basal area increments.Monthly litterfall rates in juvenile and mature stands did not change with litter removal over the study period.Annual litterfall ranged from 4.1 to 4.9 Mg ha^(−1)a^(−1)in litter removal plots and from 3.9 to 4.8 Mg ha^(−1)a^(−1)in control plots.Fine wood litter decomposition was slower in litter removal plots compared to controls,while leaf decomposition rates were similar in both.Two years of litter removal in the juvenile stand did not aff ect topsoil biogeochemical parameters but decreased available phosphorus at 20–40 cm depth relative to controls.In the mature stand,total cation exchange capacity(0–20 cm)was higher in controls(6.4 cmol c dm^(−3))relative to litter removal plots(6.3 cmol c dm^(−3)),while soil moisture(0–40 cm depth)was lower in litter removal(25.45 m 3 m^(−3))compared to control plots(26 m^(3)m^(−3))in the dry season.A non-metric multidimensional scaling ordination revealed an increased homogeneity in epigeic fauna where litter was removed.Litterfall,decomposition,diameter increment,four soil physical parameters and fourteen chemical parameters at 0–20 and 20–40 cm depth explained the diff erences in soil epigeic fauna composition between litter removal and control plots.Diameter increment decreased with litter removal only in the juvenile stand,which had reached its growth peak.The results indicate that removing excess litter to decrease fuel volume can alter soil biodiversity and edaphic conditions that negatively aff ect nutrient cycling and tree growth.展开更多
Forest management may have significant effects on forest connectivity and natural population sizes.Harvesting old-growth single trees may also change natural patterns of genetic variation and spatial genetic structure...Forest management may have significant effects on forest connectivity and natural population sizes.Harvesting old-growth single trees may also change natural patterns of genetic variation and spatial genetic structure.This study evaluated the impacts of forest management using a silvicultural system of seed trees on the genetic diversity and spatial genetic structure of Eremanthus erythropappus(DC.)MacLeish.A complete survey of 275 trees on four plots was undertaken out to compare the genetic variation of a managed stand with an unmanaged stand.We genotyped all adult and juvenile individuals 60 months after the management and compared the genetic diversity and the spatial genetic structure parameters.Genetic diversity was considered high because of an efficient gene flow between stands.There were no genetic differences between stands and no evidence of inbreeding.Genetic clustering identified a single population(K=1),indicating no genetic differentiation between managed and unmanaged stands.Adult and juvenile individuals of the unmanaged stand were more geographically structured than individuals from the managed one.There was a tendency of coancestry among juveniles at the first class of distance of the managed stand,suggesting a drift of genetic structure possibly caused by management.Understanding early responses to management on genetic diversity and stand structure is a first step to ensuring the effectiveness of conservation practices of tree species.The sustainability of forest management of E.erythropappus on genetic diversity,and more accurately,on spatial genetic structure needs evaluation over time to promote effective conservation of the population size and genetic variability.展开更多
Background:In Cerrado humid areas,veredas are considered as hygrophilous communities,marked by the presence of the Mauritia flexuosa palm tree emerging in the wetter zones.Changes in veredas ecosystems due to drought ...Background:In Cerrado humid areas,veredas are considered as hygrophilous communities,marked by the presence of the Mauritia flexuosa palm tree emerging in the wetter zones.Changes in veredas ecosystems due to drought and changes in the water table,which represent important areas for biodiversity maintenance in the Brazilian cerrado,can lead to the emergence of new landscapes and ecosystems.Assuming that the veredas are changed in species composition due to anthropogenic factors,in this study,we evaluated the flora composition and described the current vegetation profile of two veredas under different disturbances levels that are located in the north of Minas Gerais State,Brazil.Results:Altogether,2,268 individuals of 91 species belonging to 36 families were recorded.Our results demonstrated that the studied veredas were floristically different in terms of the arboreous-shrubby species composition,richness,and diversity.Despite the hygrophilous forest formations and open areas in the two veredas present typical species from these environments(same species with high importance values),the drought in the water table caused an expansion of Cerrado species in the open areas and in the hygrophilous forest.Furthermore,in the hygrophilous forest there was an increase in the abundance of species that occur in less saturated soils.Conclusion:Our results demonstrate that the studied veredas are changing in species composition due to anthropogenic factors which leads to the drought of these formations(water balance effect).These anthropogenic effects cause a modification with the expansion and increase in the abundance of typical species of other areas of Cerrado and resistant to less saturated soils,leading to the veredas collapse.Finally,future studies should investigate other veredas on a broader scale to detect changes in the water table that lead to a consequent change in vegetation structure.In this way,we will have support for the conscientious management and conservation of these areas that represent equilibrium places for the Cerrado biome.展开更多
Niche partitioning is a widespread ecological strategy within trophic guilds,ensuring the coexistence of sympatric species by reducing interspecific competition.Stable isotope analysis of carbon and nitrogen and isoto...Niche partitioning is a widespread ecological strategy within trophic guilds,ensuring the coexistence of sympatric species by reducing interspecific competition.Stable isotope analysis of carbon and nitrogen and isotopic niche metrics(width and overlap)are used as a proxy to investigate niche partitioning among species of a guild.In our study,we investigated if niche partitioning was an ecological mechanism contributing to the coexistence of granivorous birds from the same geographic region along time,employing an isotopic approach.We sampled and isotopically analyzed(δ^(13)C andδ^(15)N values)wing feathers from 58 specimens of granivorous birds collected between 1900 and 1966 in southeastern Brazil.We grouped birds according to the main habitat type used by them(forest:Cyanoloxia brissonii,Leptotila and Leptotila verreauxi;and grassland:Columbina squammata and Sicalis flaveola).We used the Isotopic Richness(IRic)metric to measure the isotopic niche width and the Isotopic Similarity(ISim)and Isotopic Nestedness(INes)metrics to measure the niche overlap between groups and species.The results of low isotopic niche overlap suggest that common granivorous birds had a clear niche partitioning in southeastern Brazil in the late past,especially through foraging in distinct habitat types(forest and grassland;ISim=0.1,INes=0.2).Niche overlaps in almost all species-by-species comparisons were low(ISim≤0.3,INes≤0.4),except between C.brissonii and L.verreauxi(ISim=0.6,INes=1.0).These results suggest that these birds,belonging to the same trophic guild,coexisted through niche and resource partitioning.Despite being considered a plastic trophic guild,the isotopic niche partitioning among granivorous birds indicates that each of these species uses a set of specific resources and habitats.This raises an ecological concern about the homogenization of landscapes across the Neotropics,oversimplifying food resources and habitats to granivorous birds.展开更多
基金This study was financed in part by the Coordenacao de Aperfeicamento de Pessoal de Nível Superior-Brazil(CAPES)-Financial Code 001 and the Conselho Nacional de Desenvolvimento Científicoe Tecnológico-Brazil(CNPq)by providing scholarship for the authors.
文摘Cerrado soils are acidic and nutrient-poor,with high content of solubilized Al 3+.Plants growing in these conditions may display adaptations to cope with high aluminum concentrations especially during early developmental stages.We investigated leaf nutritional status,and photosynthetic and growth characteristics during the initial establishment of Handroanthus impetiginosus(Mart.Ex Dc.)Mattos,a secondary tree species distributed in the Brazilian Cerrado.Our goal was to understand leaf-level traits related to diff erent aluminum concentrations.H.impetiginosus plants were cultivated in four diff erent aluminum sulfate concentrations:0,1,2,and 4 mM Al,for 40 days.We performed analyses of growth,leaf gas exchange,chloroplast pigment content,and leaf mineral nutrients.We observed a linear increase of Al leaf content as a function of Al concentration in the nutrient solution.Plants grown in 1 mM Al showed a remarkable increase of K leaf content,net photosynthesis,stomatal conductance,and transpiration,while in 4 mM Al there were reductions of N,P,and K contents,gas exchange characteristics,and height.H.impetiginosus did not have mechanisms of avoidance,compartmentalization,or resistance to high Al concentrations.Indeed,this species showed a hormetic response,with low Al concentrations stimulating and high Al concentrations inhibiting plant responses.
文摘In this study,authors analyzed value,production and area used for producing Cerrado’s main agricultural products,and data on the farms located within this biome and registered in CAR up until April 2019,by microregion.The territory considered here comprised all microregions with at least 25%of its area covered by the Cerrado biome.The production,agricultural production,and planted area values used were the averages of the 2015 to 2017 harvests,and are shown in graphs and tables,as are maps of planted areas and groups of main annual crops,semi-perennial and perennial crops.The areas designated for environmental preservation(ADPs)are the result of the sum of permanent preservation areas(APP),legal reserves(RL)and additional vegetation areas within the farms.Authors’study shows that most of Brazilian cotton,eucalyptus for charcoal,orange,sugarcane,maize and soybean are produced in Cerrado,that 28%of Cerrado are ADPs within farms,and that 16%are areas planted with cotton,eucalyptus,orange,sugarcane,maize,soybean,coffee,beans,and potatoes.The territory occupied by agricultural areas and ADPs required by the Brazilian Forest Code shows that agricultural production and environmental preservation do coexist,and gather the maintenance of essential ecosystem services provided by the ADPs together with the development of the country’s relevant agricultural production.
文摘This work focused on the prediction modeling of Cerrado occurrences in the Atlantic Rainforest predominance in the São Paulo Metropolitan Region (SPMR), the fourth largest urban area, in the city of Guarulhos, southeastern Brazil. The methodology was based on the selection of records of occurrence of Cerrado in georeferenced databases, thematic maps of geoenvironmental layers, and modeling of the distribution of species through the MaxEnt tool. Besides that, field research confirmed the presence or not of the species in the areas with a high probability of occurrence of Cerrado (≥0.7). As a result, the model observed a great capacity for the prediction of the occurrence of Cerrado in Ecotonal and anthropic regions (AUC = 0.82), revealing important hotspots such as relics from the past or Cerrado enclaves of high biodiversity. The work also points priority areas for the conservation and preservation of this increasingly endangered biome.
基金We thank the Fundacao de Amparo à Pesquisa do Estado de São Paulo(FAPESP)for financial support(Process:2008/00762-02008/10499-4) to Professor Nilce M.Martinez-Rossi for kindly providing the T.rubrum mu-tant strain.
文摘Inner bark extracts of Stryphnodendron adstringens, a leguminous tree species known as Barbatimão, are often incorporated to phytotherapic formulations due to their antimicrobial and healing activities. In this study, extracts from S. adstringens accessions collected in 12 distinct locations were investigated in order to determine the rates of tannins in inner barks and to validate S. adstringens antibacterial and antifungal effectiveness. Yields of tannins were quantified by colorimetric assay following methodology described in the Brazilian Pharmacopoeia and the antimicrobial activity was determined by microdilution technique proposed by the National Committee for Clinical Laboratory Standards using S. adstringens hydroalcoholic and aqueous extracts and semi-purified fractions. Investigated extracts did not present significant antibacterial activity though aqueous extracts exhibited antifungal effect against both Trichophyton rubrum mutant and clinical strains (MIC 156 μg/mL). A positive correlation between tannin concentration and antifungal activity was observed and the accessions collected in Delfinópolis (MG) were considered elite.
基金the Graduate Program in Ecology, Conservation and Wildlife Management (ECMVS)Institute of Biological Sciences (ICB)+1 种基金Department of Botany, Biodiversitas Foundation, Universidade Federal de Minas GeraisCoordenacao de Aperfeicoamento de Pessoal de Nível Superior (CAPES) for supporting this study
文摘Potential interactive effects and trade-offs between drivers can regulate species diversity,affecting distributions by several orders of magnitude and distribution.The decomposition ofβ-diversity into turnover and nestedness could disentangle community assembly rules and offer the opportunity to encompass the processes that structure the communities and maintain theβ-diversity on the campo rupestre.We evaluatedα-andβ-diversity and species conservation status of rocky outcrop communities in the Parque Nacional da Serra do Cipó,as well as the decomposed component of theβ-diversity index.Due to the isolation characteristics of rocky outcrops,we expect to find high taxonomic turnover among the communities.The study was performed on five quartzitic rocky outcrops divided into two sampling stations.We used field expeditions and plant inventory data of shrubs and herbaceous layers.We recorded 286 angiosperms taxa among rocky outcrops of campo rupestre of Serra do Cipó.The structure andα-diversity showed significant differences among rocky outcrops and an evident oligarchic structure in the plant communities analyzed.Taxonomicβ-diversity showed high turnover with a significant contribution of the turnover component to this index.This pattern reflects the interplay between regional and local scale processes.Therefore,we believe this approach becomes a unified framework,which allows the comparison of diversity patterns and ecological processes in rocky outcrops ecosystems.We highlight the high percentage of not evaluated species for threats and the need to fill this lack.
基金This study was supported by the Ministry of Science,Technology,Innovation and Communication-MCTICNational Council forScientific Technological Development-CNPq(grant numbers 441289/2017-7 and 306830/2017-5)the Coordination for theImprovement of Higher Education Personnel-Brasil(CAPES)-Finance Code 001 and CAPES PrInt
文摘The Brazilian Cerrado has been converted to farmland,and there is little evidence that this expansion will decrease,mainly because agriculture is the country's main economic sector.However,the impacts of intense modification of land use and land cover on surface runoff and soil erosion are still poorly un-derstood in this region.Here,we assessed surface runoff and soil loss in a woodland Cerrado area under a former pasture area,which was abandoned and has undergone a natural regeneration process for 7 years(RC).Its results were compared with that found in an undisturbed area of woodland Cerrado(CE),40-month-old eucalyptus(3.0×1.8 m)(EU),and pasture under rotational grazing(PA).The study was conducted on Red Acrisol located in the Brazilian Cerrado.We performed rainfall simulations on a plot of 0.7 m2 and using three constant rainfall intensities of 60,90,and 120 mm h-1 for 1 h.For each rainfall intensity,we carried out four repetitions using different plots in each treatment,i.e.12 plots per treat-ment studied and 48 plots in total.We noted that the soil physical properties were improved in RC and,consequently,water infiltration and soil erosion control;RC presented surface runoff and soil loss different from EU and PA(a=0.05).The macroporosity and soil bulk density affected surface runoff in RC and PA because the RC was used as pasture and is currently regenerating back to the cerrado vegetation.As the rainfall intensity increased,EU became more similar to PA,which showed the highest surface runoff and soil loss.Our findings indicate that natural regeneration processes(pasture to the cerrado vegetation)tend to improve the soil ecosystem services,improving infiltration and reducing surface runoff and soil erosion.
文摘Fruit residues may contain lactic acid bacteria(LAB)with probiotic properties.This study aimed to isolate,characterize and identify LAB isolated from Brazilian Cerrado fruit residues,as well as to evaluate the safety and functionality properties in vitro.Twenty colonies were isolated and characterized.Biochemical and morphological analyses showed 14 LAB isolates,which were identified by sequencing the 16S rRNA gene in Lactiplantibacillus plantarum/pentosus,Lacticaseibacillus casei/paracasei,Pediococcus adicilactici and Weissella cibaria/confusa.Most of the isolates showed susceptibility to antibiotics and none showed hemolytic,gelatinase,coagulase,and DNAse activity.At pH 2,the survival of most strains examined was reduced after 3h exposure-.Four showed a survival rate similar to control,while L.casei/paracasei from guapeva fruit showed a higher rate.11 isolates inhibited the growth of Esherichia coli,Staphylococcus aureus and Salmonella sp.Cluster analysis grouped the isolates according to similarity.The results highlight the specificity of the food matrix,genus,species and strain,however selected LAB strains can be submitted for further investigation of new probiotic strains.
基金supported by graduated scholarships granted to NFC and JFR,by a Research Productivity Grant(No 308992/2013-0)a research_funding(No 483117/2009-9)granted to EMV,provided by the Brazilian National Council for Scientific and Technological Development(Conselho Nacional de Desenvolvimento Cientifico e Tecnologico-CNPq).
文摘Knowledge regarding the influence of individual traits on interaction patterns in nature can help understand the topological role of individuals within a network of intrapopulation interactions.We tested hypotheses on the relationships between individuals'positions within networks(specialization and centrality)of 4 populations of the mouse opossum Gracilinanus agilis and their traits(i.e.,body length,body condition,tail length relative to body length,sex,reproductive condition,and botfly parasitism)and also seasonal effects in the Brazilian savanna.Individuals with lower body length,better body condition,and relatively shorter tail were more specialized(i.e.,less connected within the network).Individuals were also more specialized and less connected during the warm-wet season.The relationship between individuals'position in the network and body traits,however,was independent of season.We propose that specialization may arise not only as a result of preferred feed-ing strategies by more capable individuals(i.e.,those with better body condition and potentially prone to defend and access high-quality food resources)but alsobecause of morphological constraints.Smaller/younger individuals(consequently with less experience in foraging)and short-tailed individuals(less skilled to explore the vertical strata of the vegetation)would feed only on a subset of the available food resources and consequently become more specialized.Moreover,individuals are more specialized during the warm-wet season because of high competition(population-dense period)and higher ecological opportunities(resource-rich period).Therefore,our study reveals the relevance of individual traits inshaping interactionpatternsandspecialization inpopulations.
基金IFSULDEMINAS-Campus Poços de Caldas for supporting the research.
文摘Mountains exhibit a high degree of endemism and diversity,however,quantifying their biodiversity can be challenging.Similar to islands,species isolation in mountainous regions results in comparable patterns of evolution and extinction,rendering their biodiversity unique and highly susceptible to anthropogenic threats.The topographic relief in mountains plays a crucial role in creating habitat complexity,which in turn contribute to high plant diversity.Here,we investigated plant diversity in the volcano mountaintop vegetation on the Poços de Caldas Plateau,a region situated in the ecotone between the Atlantic Forest and Cerrado,characterized by natural radiation and significant anthropogenic intervention.We employed an automated approach through the filtering of georeferenced and non-georeferenced data to obtain a list of plant species in the region.Additionally,we statistically investigated the similarity among different high-altitude vegetations belonging to the campos de altitude from the Atlantic Forest and campos rupestres from the Cerrado.The plateau exhibits high plant diversity,including 1,659 specific and infraspecific taxa,especially belonging to Asteraceae and Poaceae.Our analyses suggest that geographical distance is a strong predictor of dissimilarity and that the Poços de Caldas Plateau is more floristically related to the campos rupestres,despite being associated with campos de altitude.The region possesses a unique set of biodiversity,indicating that it may be a distinct formation.Additionally,we hypothesize that Pleistocene events likely influenced the conformation of the current floristic composition in the region through species interchange between the Cerrado and Atlantic Forest.Our study also highlights the few taxa assessed for conservation status and anthropogenic threats that this habitat is facing.
基金This work is supported by the International Paper Co.from Brazil(Process 23112.000670/2015-59)by Brazilian National Council for Scientific and Technological Development(CNPq)in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior-Brasil(CAPES)-Finance Code 001.
文摘Although forests play important roles in the hydrological cycle,there is little information that relates the water retention capacity of litter in areas under passive restoration,especially in Cerrado savannas.This study relates litter levels to water holding capacity and effective water retention among forest fragments under different passive restoration stages:46,11,and 8 years to better understand litter hydrological functions in the Cerrado.Water retention capacity and effective water retention capacity of litters(unstructured materials,branches and leaves)in the field were monitored on a monthly basis.Total litter accumulation at 46 years was significantly higher than that of the other succession stages.Unstructured litter mass was significantly higher than that of leaves and branches.The 46-year stage had the highest water holding capacity in the leaf fraction,followed by unstructured material and branches.Although the water holding capacity was lower in the oldest resto-ration,this site showed the highest efficiency under field conditions.The process was quickly reestablished,as the 11-year restoration showed results closer to that for the 46-year stage in comparison to the area at 8 years.Thus,passive restoration plays a key role in soil water mainte-nance due to the influence of litter in Cerrado savannas.Deforestation and the imminent need of restoring degraded sites,highlight the need for further studies focused on bet-ter understanding of the process of forest restoration and its temporal effect on soil water recovery dynamics.
文摘We identified climatically stable areas of seasonally dry forests (SDFs) from Central Brazil through time and assessed the effectiveness of the current reserves network in representing these climatically stable areas, as well as areas of high suitability in the present or in the future only. We used an ensemble approach based on several methods for ecological niche modelling (ENMs) to obtain potential distributions 16 SDF’ species for past (last glacial maximum), present, and future (end of XXI century) climate scenarios. We then computed how many current Brazilian reserves matched both stable areas (suitable areas for all time periods), present and future geographical ranges alone for each species, in a multi-level gap analysis. We found range shifts due to climate changes for SDF’ species. Although the future geographical range and stable areas for all analyzed species matched at least with one reserve, many protected areas will lose importance in protecting suitable areas for species in the future. Moreover, the current Brazilian reserves cover only a small amount of their climatically stable areas. However, some reserves will be suitable for many SDF’ species (90%) at the same time, but climatically stable for only half of them. Our findings show that vegetation community from SDFs may persist in Brazilian territories until the end of XXI century, and challenges about long-term conservation of the SDFs may be partially reached with already existing Brazilian reserve network, however the reserves should be connected to permit habitat tracking.
文摘In this paper we analyze and compare natural regeneration in shrub-tree community in three areas below Pinus caribaea stands and a natural area （cerrado sensu stricto）. We also analyze the influence of biophysical and environmental variables on the distribution of regenerating shrub-tree species. The areas were analyzed and compared in relation to dispersal syndromes as well, being zoochory and anemochory the prevailing syndroms in the four areas. The sites below P. caribaea show a heterogeneous regen- eration with the number of species ranging from 18 to 42. We analyzed the influence of the biophysical and envi- ronmental variables performing a canonical correspon- dence analyses, being found significant values for variables distance from remnant and basal area. The species Si- paruna guianensis, Miconia albicans, Xylopia aromatica, Sclerolobium paniculatum, Casearia sylvestris and P. caribaea were the most importante ones in the four areas,
基金US National Science Foundation Award,No.1518518Complex Dynamics of Telecoupled Human and Natural System+1 种基金Michigan AgBioResearchSao Paulo Research Foundation,No.15/25892-7
文摘Diverse conservation efforts have been expanding around the globe, even under the stress of increasing agricultural production. A striking example is the supply-chain agreements put upon the Amazon forest which had reduced deforestation by 80% from the early 2000s （27,772 km2） to 2015 （6207 km2）. However, evaluation of these conservation efforts usually focused on the impacts within the Amazon biome only, while the effects that spill over to other areas （e.g., displacement of environmental pressure from one area to another） were rarely considered. Ignoring spillover effects may lead to biased or even wrong conclusions about the effectiveness of these conservation efforts because the hidden cost outside the target area of conservation may offset the achievement within it. It is thus impor- tant to assess the spillover effects of these supply-chain agreements. In this study, we used the two supply-chain agreements （i.e., Soy Moratorium and zero-deforestation beef agree- ment） implemented in the Amazon biome as examples and evaluated their spillover effects to the Cerrado. To achieve a holistic evaluation of the spillover effects, we adopted the telecou- piing framework in our analysis. The application of the telecoupling framework includes the interactions between distant systems and extends the analytical boundaries beyond the sig- natory areas, which fill the gap of previous studies. Our results indicate that the supply-chain agreements have significantly reduced deforestation by half compared to projections within the sending system （i.e., Para State in the Amazon, which exports soybeans and other agricultural products）, but at the cost of increasing deforestation in the spillover system （i.e., a 6.6 time increase in Tocantins State of the Cerrado, where deforestation was affected by interactions between the Amazon and other places）. Our study emphasizes that spillover effects should be considered in the evaluation and planning of conservation efforts, for which the telecoupling framework works as a useful tool to do that systematically.
文摘A few decades ago we sought the understanding of the functioning of Brazilian ecosystems. During these years, changes in the way land use were influenced primarily by economic issues involving the process of valuation of land in different regions. Furthermore, developments in research have provided productive increments that were well characterized in some phases. This paper aims to trace a brief history of the distribution of grassland ecosystems in Brazil and show how it has been the advances in research on forages and pastures in the country, pointing its evolution, transition times and trends. Moreover, it purports to show a perspective of the dynamics of occupation of Brazilian territory by these ecosystems. The information is presented on three occasions, seeking to encourage understanding of where livestock grazing occurs and how the dynamics of occupation of the area was favored by the search. Also, it shows how the research was fundamental for Brazil occupy little arable areas considered, making the country one of the largest producers of cattle in the world.
基金Sao Paulo Research Foundation(FAPESP)for financial support through the grants:#2009/54208-6Fapesp-Microsoft Research Institute#2013/50155-0+6 种基金Fapesp-Vale#2010/51307-0,#2021/10639-5 to LPCMthrough fellowships FAPESP#2015/10754-8 to MGGC and#2019/09248-1 to ASSCoordena??o de Aperfei?oamento de Pessoal de Nível Superior–(CAPES)for scholarships granted to MGGC(Process#88887.583309/2020-00)PPL(#88887.583146/2020-00)JSS(CAPES Finance Code 001)National Council for Scientific and Technological Development(CNPq)for the grants:CNPq-PVE#400717/2013-1 and PDJ#150404/2016-6 to SLSfor the productivity fellowship and grant#311820/2018-2,#306563/2022-3 to LPCM。
文摘Despite the exceptional species richness and endemism,the environmental drivers of plant diversity along old tropical mountains remain underexplored.The respective importance of vegetation types,elevation,slope,and soil to drive diversity across life-forms is poorly addressed.Here,we tested whether environmental variables drove local and regional plant diversity along an old tropical mountain according to the three main life-forms:graminoids,herbaceous and woody species.We sampled all Angiosperm species on 180 plots across five elevations,at the tropical old-mountain region of Serra do Cipó,South-eastern Brazil.We assessed soil,slope,and vegetation types,and calculated richness and beta-diversity,applying generalized least square models,linear mixed-models and partial Mantel tests to test for relationships.Richness of graminoids and herbaceous species increased with greater elevation and more nutrient-impoverished soils,while woody richness showed the inverse pattern.Beta-diversity was primarily driven by species turnover,correlated with elevation and soil and higher in less dominant vegetation types,with unique species.Despite the limited elevational range in these old mountains,it still played an important role in filtering woody species,while fostering graminoid and herbaceous species.Conservation and restoration actions need to foster the high regional diversity supported by the old mountain heterogeneous landscape and the diversity of life-forms,especially the dominant and highly diverse grassy component.
基金This study was financed in part by the Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior-Brasil(CAPES)-Finance Code 001.
文摘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.
基金supported by the Coordination for the Improvement of Higher Education Personnel(CAPES)the research funding of the University of Brasília。
文摘The little layer of tree plantations provides primary nutrients for uptake,buff ers changes in soil moisture,and provides habitat and substrate to soil epigeic fauna.However,this layer in eucalypt plantations is often removed to reduce fuel load during the fi re season in the Brazilian savanna(Cerrado).Therefore,it is necessary to quantify the eff ects of changes in litter dynamics on the function of these plantations,on key nutrient cycling processes and on epigeic fauna diversity and abundance.In two adjacent stands(one juvenile and one mature),the consequences of two years of litter removal were quantifi ed as monthly litterfall,leaf and fi ne wood litter decomposition,epigeic fauna abundance and diversity,soil biogeochemical variables,and tree diameter and basal area increments.Monthly litterfall rates in juvenile and mature stands did not change with litter removal over the study period.Annual litterfall ranged from 4.1 to 4.9 Mg ha^(−1)a^(−1)in litter removal plots and from 3.9 to 4.8 Mg ha^(−1)a^(−1)in control plots.Fine wood litter decomposition was slower in litter removal plots compared to controls,while leaf decomposition rates were similar in both.Two years of litter removal in the juvenile stand did not aff ect topsoil biogeochemical parameters but decreased available phosphorus at 20–40 cm depth relative to controls.In the mature stand,total cation exchange capacity(0–20 cm)was higher in controls(6.4 cmol c dm^(−3))relative to litter removal plots(6.3 cmol c dm^(−3)),while soil moisture(0–40 cm depth)was lower in litter removal(25.45 m 3 m^(−3))compared to control plots(26 m^(3)m^(−3))in the dry season.A non-metric multidimensional scaling ordination revealed an increased homogeneity in epigeic fauna where litter was removed.Litterfall,decomposition,diameter increment,four soil physical parameters and fourteen chemical parameters at 0–20 and 20–40 cm depth explained the diff erences in soil epigeic fauna composition between litter removal and control plots.Diameter increment decreased with litter removal only in the juvenile stand,which had reached its growth peak.The results indicate that removing excess litter to decrease fuel volume can alter soil biodiversity and edaphic conditions that negatively aff ect nutrient cycling and tree growth.
基金supported by the Fundacao de Amparo a Pesquisa do Estado de Minas Gerais (FAPEMIG)[CRA APQ-02641-14]in part by the Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior-Brasil(CAPES)-Finance Code 001。
文摘Forest management may have significant effects on forest connectivity and natural population sizes.Harvesting old-growth single trees may also change natural patterns of genetic variation and spatial genetic structure.This study evaluated the impacts of forest management using a silvicultural system of seed trees on the genetic diversity and spatial genetic structure of Eremanthus erythropappus(DC.)MacLeish.A complete survey of 275 trees on four plots was undertaken out to compare the genetic variation of a managed stand with an unmanaged stand.We genotyped all adult and juvenile individuals 60 months after the management and compared the genetic diversity and the spatial genetic structure parameters.Genetic diversity was considered high because of an efficient gene flow between stands.There were no genetic differences between stands and no evidence of inbreeding.Genetic clustering identified a single population(K=1),indicating no genetic differentiation between managed and unmanaged stands.Adult and juvenile individuals of the unmanaged stand were more geographically structured than individuals from the managed one.There was a tendency of coancestry among juveniles at the first class of distance of the managed stand,suggesting a drift of genetic structure possibly caused by management.Understanding early responses to management on genetic diversity and stand structure is a first step to ensuring the effectiveness of conservation practices of tree species.The sustainability of forest management of E.erythropappus on genetic diversity,and more accurately,on spatial genetic structure needs evaluation over time to promote effective conservation of the population size and genetic variability.
基金supported by the Long-term Ecological Research Network(PELD-VERE)of the Conselho Nacional de Desenvolvimento Científico e Tecnologico(CNPq 441440/2016-9,441583/2020-2,308877/2019-5),Coordenaçao de Aperfeiçoamento de Pessoal de Nível Superior(CAPES 88887.136273/2017-00)Fundaçao de Amparoa Pesquisa do Estado de Minas Gerais(FAPEMIG APQ-04816-17,CRAPPM-00539-18,APQ-04816-17)+1 种基金FAPEMIG(FAPEMIG/RED-00253-16)for the supportthe second author scholarship.
文摘Background:In Cerrado humid areas,veredas are considered as hygrophilous communities,marked by the presence of the Mauritia flexuosa palm tree emerging in the wetter zones.Changes in veredas ecosystems due to drought and changes in the water table,which represent important areas for biodiversity maintenance in the Brazilian cerrado,can lead to the emergence of new landscapes and ecosystems.Assuming that the veredas are changed in species composition due to anthropogenic factors,in this study,we evaluated the flora composition and described the current vegetation profile of two veredas under different disturbances levels that are located in the north of Minas Gerais State,Brazil.Results:Altogether,2,268 individuals of 91 species belonging to 36 families were recorded.Our results demonstrated that the studied veredas were floristically different in terms of the arboreous-shrubby species composition,richness,and diversity.Despite the hygrophilous forest formations and open areas in the two veredas present typical species from these environments(same species with high importance values),the drought in the water table caused an expansion of Cerrado species in the open areas and in the hygrophilous forest.Furthermore,in the hygrophilous forest there was an increase in the abundance of species that occur in less saturated soils.Conclusion:Our results demonstrate that the studied veredas are changing in species composition due to anthropogenic factors which leads to the drought of these formations(water balance effect).These anthropogenic effects cause a modification with the expansion and increase in the abundance of typical species of other areas of Cerrado and resistant to less saturated soils,leading to the veredas collapse.Finally,future studies should investigate other veredas on a broader scale to detect changes in the water table that lead to a consequent change in vegetation structure.In this way,we will have support for the conscientious management and conservation of these areas that represent equilibrium places for the Cerrado biome.
基金supported by the Sāo Paulo Research Foundation(FAPESP)postdoctoral fellowship grants 2018-05970-1 and 2019-11901-5。
文摘Niche partitioning is a widespread ecological strategy within trophic guilds,ensuring the coexistence of sympatric species by reducing interspecific competition.Stable isotope analysis of carbon and nitrogen and isotopic niche metrics(width and overlap)are used as a proxy to investigate niche partitioning among species of a guild.In our study,we investigated if niche partitioning was an ecological mechanism contributing to the coexistence of granivorous birds from the same geographic region along time,employing an isotopic approach.We sampled and isotopically analyzed(δ^(13)C andδ^(15)N values)wing feathers from 58 specimens of granivorous birds collected between 1900 and 1966 in southeastern Brazil.We grouped birds according to the main habitat type used by them(forest:Cyanoloxia brissonii,Leptotila and Leptotila verreauxi;and grassland:Columbina squammata and Sicalis flaveola).We used the Isotopic Richness(IRic)metric to measure the isotopic niche width and the Isotopic Similarity(ISim)and Isotopic Nestedness(INes)metrics to measure the niche overlap between groups and species.The results of low isotopic niche overlap suggest that common granivorous birds had a clear niche partitioning in southeastern Brazil in the late past,especially through foraging in distinct habitat types(forest and grassland;ISim=0.1,INes=0.2).Niche overlaps in almost all species-by-species comparisons were low(ISim≤0.3,INes≤0.4),except between C.brissonii and L.verreauxi(ISim=0.6,INes=1.0).These results suggest that these birds,belonging to the same trophic guild,coexisted through niche and resource partitioning.Despite being considered a plastic trophic guild,the isotopic niche partitioning among granivorous birds indicates that each of these species uses a set of specific resources and habitats.This raises an ecological concern about the homogenization of landscapes across the Neotropics,oversimplifying food resources and habitats to granivorous birds.
