Brazilian Amazon Rainforest Research Articles

The influence of spatial sampling scales on ant-plant interaction network architecture.

Despite great interest in metrics to quantify the structure of ecological networks, the effects of sampling and scale remain poorly understood. In fact, one of the most challenging issues in ecology is how to define suitable scales (i.e., temporal or spatial) to accurately describe and understand ecological systems. Here, we sampled a series of ant-plant interaction networks in the southern Brazilian Amazon rainforest in order to determine whether the spatial sampling scale, from local to regional, affects our understanding of the structure of these networks. To this end, we recorded ant-plant interactions in adjacent 25×30m subplots (local sampling scale) nested within twelve 250×30m plots (regional sampling scale). Moreover, we combined adjacent or random subplots and plots in order to increase the spatial sampling scales at the local and regional levels. We then calculated commonly used binary and quantitative network-level metrics for both sampling scales (i.e., number of species and interactions, nestedness, specialization and modularity), all of which encompass a wide array of structural patterns in interaction networks. We observed increasing species and interactions across sampling scales, and while most network descriptors remained relatively constant at the local level, there was more variation at the regional scale. Among all metrics, specialization was most constant across different spatial sampling scales. Furthermore, we observed that adjacent assembly did not generate more variation in network descriptor values compared to random assembly. This finding indicates that the spatially aggregated distribution of species/individuals and abiotic conditions does not affect the organization of these interacting assemblages. Our results have a direct impact on our empirical and theoretical understanding of the ecological dynamics of species interactions by demonstrating that small spatial sampling scales should suffice to record some patterns commonly found in ant-plant interaction networks in a highly diverse tropical rainforest.

Federal enforcement and reduction of deforestation in the Brazilian Amazon

Agricultural activities are considered the main cause of deforestation in the Brazilian Amazon rainforest. Command and control operations of the Brazilian government, fines and monitoring of illegal activities are institutional mechanisms to reduce deforestation in the region, mainly supervising the agricultural activities. The objective of this study is to analyze the effects of agricultural activities on deforestation in the 21 st century, considering the role of government and enforcement to reduce deforestation rates in priority municipalities in the Amazon. Using panel data analysis with 335 municipalities of Mato Grosso, Para, and Rondonia, including high-priority municipalities to combat deforestation, we show that cattle ranching remains the leading cause of deforestation in the Amazon rainforest, while soybean cultivation and others temporary crops do not yet represent a major threat. In addition, it is observed that enforcement operations produce positive effects in reducing deforestation, combating activities not conforming to the legislation and sustainability standards. Although this institutional mechanism of enforcement is reaching its limits, slowing the reduction of deforestation rates in recent years.

Fertile ground for unsustainable development in Brazil

News outlets across the world present a common assessment of the deforestation of the Amazon rainforest in Brazil: it is exponentially rising, at a record rate1. In this context, it may be surprising to note that, the protection of the environment is fundamental to the constitutional framework of Brazil, with the provision that ‘everyone has the right to an ecologically balanced environment, common good of the people and essential to the healthy quality of life, imposing on the public sector and the community the duty to defend and preserve it for present and future generations’ (Art. 225, Federal Constitution of Brazil). In this provision, the environment, when balanced and thus preserved, enables the promotion of quality of life for present and future generations. This intergenerational dimension brings to light the notion of sustainable development. This concept integrates development – which, for the Brazilian economist and intellectual Celso Furtado, embraces a unique social project related to the non-depreciation of labour and of natural resources, not reducible to mere economic growth – and sustainability – which includes social, environmental, territorial, economic, cultural, ecological and political criteria2. In the constitutional instrument, the duty of environmental defence and preservation is imposed on the public sector and on the community. In relation to the public sector, this protection can be achieved by legislative methods, through infraconstitutional instruments; by the judiciary, though judicial demands; and by the executive – the President, their ministries and secretaries. Regarding the community, such protection can be collectively supported by social groups: for example, associations and trade unions. Environmental protection dismantled As is widely reported, the Brazilian executive has played a central role in the recent escalation of destruction of the Amazon. For the current government, elected in October 2018 and in power since January 2019, the objective of economic growth is regarded as irreconcilable with environmental preservation – particularly from the perspective of expanding the agricultural frontier and agribusiness – resulting in attacks on existing laws and restructuring of the Ministry of Environment. Consequently, the resolutions implemented since January 2019 pertinent to environmental policy demonstrate the relativisation of the preservation of the environment and, above all, of ecosystems such as the Amazon. In the government’s dismantling of the existing system of protection, certain measures have been critical: the abolition of the Secretariat of Climate Change and Forests in the Ministry of the Environment; the transfer of the Brazilian Forest Service from the Ministry of the Environment to the Ministry of the Agriculture; the blocking of funds for fire-fighting and enforcement, leading to a substantial drop in the number of operations and, consequently, fines imposed; the considerable reduction of CONAMA (National Environmental Council) advisors; the dismissal and precarious replacement of state overseers of IBAMA (Brazilian Institute of Environment and Renewable Natural Resources); and the abolition of the Amazon Fund Steering Committee. Statements made by the government seeking to discredit entities dedicated to environmental research, such as the INPE (National Institute for Space Research) monitoring system, or relativise the problem of the lack of environmental protection, are also taking their toll. In order to diminish and distract from legitimate environmental concerns, the President of Brazil, Jair Bolsonaro, along with his ministers, have stated that alarming data on deforestation are nothing more than fake news and sensationalism. Recently President Bolsonaro stated that deforestation and forest fires are ‘cultural’ and ‘will never end’3. Given this situation, it is not surprising that the estimated deforestation rate in the nine states constituting the Amazônia Legal (‘Brazil’s Legal Amazon’, the region of Brazil in the Amazon basin) increased nearly thirty percent from August 2018 to July 20194. This rate represents the deforestation of an area of 9.762 km2, equivalent to a little less than one third of the total area of Belgium. The conduct of the federal government demonstrates that, despite the escalation in the rate of deforestation, the Executive intends to neither end nor hinder this phenomenon. The logic underpinning the dismantling of Brazilian environmental policy has no concern for present or future generations. Unions’ defence of the rainforest According to the aforementioned constitutional provision, the duty of defence and preservation of the environment does not end with the public sector – although its action clearly...

Fertile ground for unsustainable development in Brazil

News outlets across the world present a common assessment of the deforestation of the Amazon rainforest in Brazil: it is exponentially rising, at a record rate1. In this context, it may be surprising to note that, the protection of the environment is fundamental to the constitutional framework of Brazil, with the provision that ‘everyone has the right to an ecologically balanced environment, common good of the people and essential to the healthy quality of life, imposing on the public sector and the community the duty to defend and preserve it for present and future generations’ (Art. 225, Federal Constitution of Brazil). In this provision, the environment, when balanced and thus preserved, enables the promotion of quality of life for present and future generations. This intergenerational dimension brings to light the notion of sustainable development. This concept integrates development – which, for the Brazilian economist and intellectual Celso Furtado, embraces a unique social project related to the non-depreciation of labour and of natural resources, not reducible to mere economic growth – and sustainability – which includes social, environmental, territorial, economic, cultural, ecological and political criteria2. In the constitutional instrument, the duty of environmental defence and preservation is imposed on the public sector and on the community. In relation to the public sector, this protection can be achieved by legislative methods, through infraconstitutional instruments; by the judiciary, though judicial demands; and by the executive – the President, their ministries and secretaries. Regarding the community, such protection can be collectively supported by social groups: for example, associations and trade unions. Environmental protection dismantled As is widely reported, the Brazilian executive has played a central role in the recent escalation of destruction of the Amazon. For the current government, elected in October 2018 and in power since January 2019, the objective of economic growth is regarded as irreconcilable with environmental preservation – particularly from the perspective of expanding the agricultural frontier and agribusiness – resulting in attacks on existing laws and restructuring of the Ministry of Environment. Consequently, the resolutions implemented since January 2019 pertinent to environmental policy demonstrate the relativisation of the preservation of the environment and, above all, of ecosystems such as the Amazon. In the government’s dismantling of the existing system of protection, certain measures have been critical: the abolition of the Secretariat of Climate Change and Forests in the Ministry of the Environment; the transfer of the Brazilian Forest Service from the Ministry of the Environment to the Ministry of the Agriculture; the blocking of funds for fire-fighting and enforcement, leading to a substantial drop in the number of operations and, consequently, fines imposed; the considerable reduction of CONAMA (National Environmental Council) advisors; the dismissal and precarious replacement of state overseers of IBAMA (Brazilian Institute of Environment and Renewable Natural Resources); and the abolition of the Amazon Fund Steering Committee. Statements made by the government seeking to discredit entities dedicated to environmental research, such as the INPE (National Institute for Space Research) monitoring system, or relativise the problem of the lack of environmental protection, are also taking their toll. In order to diminish and distract from legitimate environmental concerns, the President of Brazil, Jair Bolsonaro, along with his ministers, have stated that alarming data on deforestation are nothing more than fake news and sensationalism. Recently President Bolsonaro stated that deforestation and forest fires are ‘cultural’ and ‘will never end’3. Given this situation, it is not surprising that the estimated deforestation rate in the nine states constituting the Amazônia Legal (‘Brazil’s Legal Amazon’, the region of Brazil in the Amazon basin) increased nearly thirty percent from August 2018 to July 20194. This rate represents the deforestation of an area of 9.762 km2, equivalent to a little less than one third of the total area of Belgium. The conduct of the federal government demonstrates that, despite the escalation in the rate of deforestation, the Executive intends to neither end nor hinder this phenomenon. The logic underpinning the dismantling of Brazilian environmental policy has no concern for present or future generations. Unions’ defence of the rainforest According to the aforementioned constitutional provision, the duty of defence and preservation of the environment does not end with the public sector – although its action clearly...

Potential increase of legal deforestation in Brazilian Amazon after Forest Act revision

The Brazilian Amazon rainforest is protected largely by command and control regulation of public and private land. The Brazilian Forest Act requires private landholders within the Amazon to set aside 80% of their land as legal reserves for nature protection, but this requirement can be reduced to 50% if more than 65% of a state’s territory is protected public land (for example, public conservation units and indigenous reserves). In the ongoing land designation process in Brazil, some Amazonian states may cross this 65% threshold. We assess the potential reduction in the legal reserve requirement from 80% to 50%, through spatially explicit modelling of scenarios concerning land tenure consolidation, employing up-to-date databases on land ownership. Depending on the outcome of land designation processes and political priorities, some 6.5–15.4 million hectares of private land previously protected as legal reserves may become available for legal deforestation. While protection of public land is crucial for safeguarding the Amazon, revisions of federal and state legislation may be needed to avoid the further extension of protected public land triggering increased legal deforestation on private lands. Zero-deforestation commitments and other initiatives may mitigate impacts in the absence of such revision.

Passiflora bernaccii (Passifloraceae s.s.), a new species from Acre, Brazil

Passiflora bernaccii is described and illustrated here as a new species belonging to P. subgenus Astrophea section Pseudoastrophea from the Brazilian Amazon Rainforest. The new species has similarities with P. hexagonocarpa, P. rhamnifolia and P. tessmannii, but differs mainly by the shape of the outer filaments of the corona, shape of the operculum and presence of trochlea. Palynological support for the classification is also discussed.

Review of the genus Ceratotarsonemus De Leon, 1956 (Acari: Prostigmata: Tarsonemidae), with description of a new species from the Amazon Forest.

The genus Ceratotarsonemus De Leon (Acari: Prostigmata: Tarsonemidae) is reviewed here, with the addition of an updated key for the genus. Ceratotarsonemus amazonicus, sp. nov., found in the Brazilian Amazon rainforest, is described. Phase contrast (PC), differential interference contrast (DIC), low temperature scanning electron microscopy (LT-SEM) and confocal microscopy (CLSM) micrographs are provided. Biological and ecological aspects about the role of this species in its ecosystem are also discussed.

Biomass burning emission disturbances of isoprene oxidation in a tropical forest

Abstract. We present a characterization of the chemical composition of the atmosphere of the Brazilian Amazon rainforest based on trace gas measurements carried out during the South AMerican Biomass Burning Analysis (SAMBBA) airborne experiment in September 2012. We analyzed the observations of primary biomass burning emission tracers, i.e., carbon monoxide (CO), nitrogen oxides (NOx), ozone (O3), isoprene, and its main oxidation products, methyl vinyl ketone (MVK), methacrolein (MACR), and isoprene hydroxy hydroperoxide (ISOPOOH). The focus of SAMBBA was primarily on biomass burning emissions, but there were also several flights in areas of the Amazon forest not directly affected by biomass burning, revealing a background with a signature of biomass burning in the chemical composition due to long-range transport of biomass burning tracers from both Africa and the eastern part of Amazonia. We used the [MVK + MACR + ISOPOOH] ∕ [isoprene] ratio and the hydroxyl radical (OH) indirect calculation to assess the oxidative capacity of the Amazon forest atmosphere. We compared the background regions (CO < 150 ppbv), fresh and aged smoke plumes classified according to their photochemical age ([O3] ∕ [CO]), to evaluate the impact of biomass burning emissions on the oxidative capacity of the Amazon forest atmosphere. We observed that biomass burning emissions disturb the isoprene oxidation reactions, especially for fresh plumes ([MVK + MACR + ISOPOOH] ∕ [isoprene] = 7) downwind. The oxidation of isoprene is higher in fresh smoke plumes at lower altitudes (∼ 500 m) than in aged smoke plumes, anticipating near the surface a complex chain of oxidation reactions which may be related to secondary organic aerosol (SOA) formation. We proposed a refinement of the OH calculation based on the sequential reaction model, which considers vertical and horizontal transport for both biomass burning regimes and background environment. Our approach for the [OH] estimation resulted in values on the same order of magnitude of a recent observation in the Amazon rainforest [OH] ≅ 106 (molecules cm−3). During the fresh plume regime, the vertical profile of [OH] and the [MVK + MACR + ISOPOOH] ∕ [isoprene] ratio showed evidence of an increase in the oxidizing power in the transition from planetary boundary layer to cloud layer (1000–1500 m). These high values of [OH] (1.5 × 106 molecules cm−3) and [MVK + MACR + ISOPOOH] ∕ [isoprene] (7.5) indicate a significant change above and inside the cloud decks due to cloud edge effects on photolysis rates, which have a major impact on OH production rates.

Molecular mechanisms underlying intraspecific variation in snake venom

Elucidating the molecular mechanisms underlying snake venom variability provides important clues for understanding how the biological functions of this powerful toxic arsenal evolve. We analyzed in detail individual transcripts and venom protein isoforms produced by five specimens of a venomous snake (Bothrops atrox) from two nearby but genetically distinct populations from the Brazilian Amazon rainforest which show functional similarities in venom properties. Individual variation was observed among the venoms of these specimens, but the overall abundance of each general toxin family was conserved both in transcript and in venom protein levels. However, when expression of independent paralogues was analyzed, remarkable differences were observed within and among each toxin group, both between individuals and between populations. Transcripts for functionally essential venom proteins (“core function” proteins) were highly expressed in all specimens and showed similar transcription/translation rates. In contrast, other paralogues (“adaptive” proteins) showed lower expression levels and the toxins they coded for varied among different individuals. These results provide support for the inferences that (a) expression and translational differences play a greater role in defining adaptive variation in venom phenotypes than does sequence variation in protein coding genes and (b) convergent adaptive venom phenotypes can be generated through different molecular mechanisms. SignificanceAnalysis of individual transcripts and venom protein isoforms produced by specimens of a venomous snake (Bothrops atrox), from the Brazilian Amazon rainforest, revealed that transcriptional and translational mechanisms contribute to venom phenotypic variation. Our finding of evidence for high expression of toxin proteins with conserved function supports the hypothesis that the venom phenotype consists of two kinds of proteins: conserved “core function” proteins that provide essential functional activities with broader relevance and less conserved “adaptive” proteins that vary in expression and may permit customization of protein function. These observations allowed us to suggest that genetic mechanisms controlling venom variability are not restricted to selection of gene copies or mutations in structural genes but also to selection of the mechanisms controlling gene expression, contributing to the plasticity of this important phenotype for venomous snakes.

Development of non-linear models predicting daily fine particle concentrations using aerosol optical depth retrievals and ground-based measurements at a municipality in the Brazilian Amazon region

Epidemiological studies generally use particulate matter measurements with diameter less 2.5 μm (PM2.5) from monitoring networks. Satellite aerosol optical depth (AOD) data has considerable potential in predicting PM2.5 concentrations, and thus provides an alternative method for producing knowledge regarding the level of pollution and its health impact in areas where no ground PM2.5 measurements are available. This is the case in the Brazilian Amazon rainforest region where forest fires are frequent sources of high pollution. In this study, we applied a non-linear model for predicting PM2.5 concentration from AOD retrievals using interaction terms between average temperature, relative humidity, sine, cosine of date in a period of 365,25 days and the square of the lagged relative residual. Regression performance statistics were tested comparing the goodness of fit and R2 based on results from linear regression and non-linear regression for six different models. The regression results for non-linear prediction showed the best performance, explaining on average 82% of the daily PM2.5 concentrations when considering the whole period studied. In the context of Amazonia, it was the first study predicting PM2.5 concentrations using the latest high-resolution AOD products also in combination with the testing of a non-linear model performance. Our results permitted a reliable prediction considering the AOD-PM2.5 relationship and set the basis for further investigations on air pollution impacts in the complex context of Brazilian Amazon Region.

Impacts of Agricultural Practices and Individual Life Characteristics on Ecosystem Services: A Case Study on Family Farmers in the Context of an Amazonian Pioneer Front.

In tropical forests farmers are among the most important agents of deforestation. At the interface between societies and their environment, ecosystem services (ES) is an integrated working framework through which natural and anthropogenic dimensions can be addressed. Here, we aimed to understand to what extent farmers impact ES availability. Based on case studies in three locations in the Brazilian Amazon rainforest, we performed statistical analyses at 135 sampling points and 110 farms to link socioeconomic and ES data, both derived from field work. The socioeconomic data characterized agricultural production, sociological characteristics, and quality of life. ES data were obtained from statistical analyses that yielded a multiple ES indicator for each sampling point and farm. Our results produced three main findings: first, the establishment of ES associations is due more to agricultural production characteristics than to sociological and quality-of-life factors. Second, the impact of agricultural production on ES availability depends on the level of total incomes. An increase in incomes causes a decrease in the forest cover that provides many ES and an increase in other areas that provide fewer ES. Finally, our analyses show a very strong site effect that probably expresses the heterogeneity of the biophysical contexts, but also the importance for ES availability of the historical depth of deforestation and/or the role of specific public policies. Finding ways of producing an alternative impact on ES availability and establishing specific ES associations will therefore depend more on changes in the global political context than in individual practices.

Metapolybia araujoi, a new species of swarming social wasp from the Brazilian Amazon rainforest (Vespidae: Polistinae)

A new species of Metapolybia, collected in Pará State, Brazil, by Adolph Ducke, in 1902, is described and comparative remarks are given.

Epidemiologically inspired approaches to land-use policy evaluation: The influence of the Rural Environmental Registry (CAR) on deforestation in the Brazilian Amazon

Environmental policy evaluation is crucial to determining if policy objectives were achieved. In most cases, some of the outcomes can be measured but a proper statistical analysis is difficult to achieve since the data may not represent a random sample (i.e., the data is biased), are not representative of the population or cannot be compared to a control group. This work adapts quasi-experimental statistical methods widely used in epidemiological studies that could be applied to land use policy evaluation in situations of relatively poor data. In order to test and develop this set of methods, we evaluated the effect of a land-use policy known as the rural environmental registry (CAR) on the reduction of deforestation rates in the Brazilian Amazon rainforest. The random variable of interest is the number of deforested hectares in given private properties and the statistic of interest is the difference of the annual deforestation rate between the properties before and after the policy intervention. Since no formal statistical distribution properly fit the data, non-parametrical approaches such as Monte Carlo simulations and Bootstrap were used. Data from the Brazilian states of Mato Grosso and Pará were used, with different time periods and three rural property size classes. Results show that the properties inside the Rural Environmental Registry have reduced their deforestation rates in some property classes and time periods, but this effect has not been systematic across time and space indicating that the policy is only partially effective. We conclude that the proposed statistical methods can be useful in environmental policy evaluation in different contexts due to low demands in terms of data availability and statistical distribution assumptions.

Desutterella n. gen., a new genus of Luzarinae (Orthoptera: Grylloidea: Phalangopsidae) and the first report of the Aracambiae group Souza-Dias & Desutter-Grandcolas, 2014 in the Amazon.

A new genus and two new species of Luzarinae cricket (Grylloidea, Phalangopsidae) are described from the Amazon Rainforest of Brazil and Colombia. Desutterella manauara n. gen. n. sp. and D. colombiana n. gen. n. sp. are described based in characters of external morphology and genitalia. The new genus is characterized by the presence of reduced and pubescent male forewings, with stridulatory vein visible but other areas for sound production and propagation absent, and file teeth very reduced, vestigial. Regarding the male genitalia, Desutterella n. gen. presents an extra projection in the pseudepiphallic paramere 2, a condition not observed in the Aracambiae until now. Besides the description, we provide morphological evidence for the glandular nature of the metanotum of males through scanning electron microscopy analysis, a discussion about the morphological and genital features of this new genus, and a distribution map of the Aracambiae group.

Diversity of iron cave-dwelling mygalomorph spiders from Pará, Brazil, with description of three new species (Araneae)

Mygalomorph spiders are rarely found in caves and most of the records appear as accidental or restricted to small populations. The present study took place in iron formations in Carajas region, southeastern Para state, eastern Brazilian Amazon rainforest. Each cave was sampled twice: dry season (from May to October) and wet season (from November to April). Of the 242 caves sampled, we found mygalomorphs in 98 (40%). The survey yielded 254 specimens, 223 (87.8%) juveniles. Of the 14 species recorded, nine were represented by adults: Dolichothele tucuruiense (Guadanucci, 2007), Hapalopus aymara Perdomo, Panzera & Perez-Miles, 2009, Acanthoscurria geniculata (CL Koch, 1841), Theraphosa blondi (Latreille, 1804), Nhandu coloratovillosus (Schmidt, 1998), Fufius minusculus Ortega, Nagahama, Motta & Bertani, 2013, and three new are species described here: Guyruita metallophila n. sp., Hapalopus serrapelada n. sp., and Idiops carajas n. sp. Five other “morphospecies” were represented by juveniles only: Ummidia sp....

Understory host plant and insect gall diversity changes across topographic habitats differing in nutrient and water stress in the Brazilian Amazon rainforest

ABSTRACT Topographic gradients in terra firme forests are associated with pronounced changes in soil texture, soil nutrients and distance to the water-table, thereby creating different hydric and nutritional conditions for plants and their associated herbivore community. The aim of this study was to investigate galling species and host plant richness and gall species composition across topographic habitats differing in nutrient and water stress in the Brazilian Amazon rainforest. Nineteen 250 x 3 m plots were randomly sampled in the valley, slope, plateau-slope transition, and plateau habitats in terra firme forests. All individual dicotyledonous plants 1 to 3 meters high were examined for the presence of insect galls. Galling species and host plant richness differed significantly among the studied habitats and were higher in slope habitats (drier habitats), as expected. More humid areas (valleys) showed the lowest richness of galling species, and a lower number of understory host plants. PERMANOVA and PERMDISP results demonstrated that the gall species composition differed significantly in the valley, slope, plateau-slope transition, and plateau areas. However, these structural differences in species composition could be due to unequal dispersion of variability among forest habitats. Our data suggested that spatial heterogeneity, such as a mosaic of local water status and nutrient availability resulting from the topographic conditions, can affect host plants and their associated galling insects.

Investigating the mechanisms responsible for the lack of surface energy balance closure in a central Amazonian tropical rainforest

This work investigates the diurnal and seasonal behavior of the energy balance residual (E) that results from the observed difference between available energy and the turbulent fluxes of sensible heat (H) and latent heat (LE) at the FLUXNET BR-Ma2 site located in the Brazilian central Amazon rainforest. The behavior of E is analyzed by extending the eddy covariance averaging length from 30min to 4h and by applying an Information Flow Dynamical Process Network to diagnose processes and conditions affecting E across different seasons. Results show that the seasonal turbulent flux dynamics and the Bowen ratio are primarily driven by net radiation (Rn), with substantial sub-seasonal variability. The Bowen ratio increased from 0.25 in April to 0.4 at the end of September. Extension of the averaging length from 0.5 (94.6% closure) to 4h and thus inclusion of longer timescale eddies and mesoscale processes closes the energy balance and lead to an increase in the Bowen ratio, thus highlighting the importance of additional H to E. Information flow analysis reveals that the components of the energy balance explain between 25 and 40% of the total Shannon entropy with higher values during the wet season than the dry season. Dry season information flow from the buoyancy flux to E are 30–50% larger than that from H, indicating the potential importance of buoyancy fluxes to closing E. While the low closure highlights additional sources not captured in the flux data and random measurement errors contributing to E, the findings of the information flow and averaging length analysis are consistent with the impact of mesoscale circulations, which tend to transport more H than LE, on the lack of closure.

Diversidade de mamíferos do baixo Rio Jufari, Roraima, Brasil

Faunal inventories are essential to directly access the diversity of a region. Although the Amazon rainforest exhibit large estimates of mammal species richness, the region still exhibits large sampling gaps. Aiming to fill a sampling gap on the mammalian diversity in the Brazilian Amazon rainforest, we conducted an inventory of non-volant mammals at “terra firme” forest near the mouth of Rio Jufari, an affluent of north bank of Rio Negro, near its confluence with Rio Branco. To sample small mammals, we applied a total effort of 3,673 live trap nights, and 2,700 pitfall trap nights. For large mammals we performed unstandardized line transect census, and included, as well, records from occasional encounters and material donated by Caicubi community members. The pitfall traps proved to be extremely valuable for the small mammals sampling. We observed a low mammalian diversity when compared to other inventories throughout the Amazon basin. We recorded 27 species belonging to 25 genera, 16 families and nine orders of the Class Mammalia. The majority of recorded species is known from Guianan subregion. However, we present: extension on the known distribution records for Marmosops bishopi; taxonomic comments on the marsupial Monodelphis brevicaudata; and new collection record for species of the genera Oecomys and Makalata. It is remarkable the extremely low number of species from the order Primates. Data based on interviews suggested that this small number of primate specimens is historical, and areas closer to Rio Negro and Rio Branco exhibit higher diversity. Our samples showed that Rio Negro-Rio Branco confluence do not present an endemic mammalian fauna, once the region shares its mammalian composition with other confluence areas in the Amazon basin, especially with those on the northeastern Amazon region.

Soil Carbon Stock and Particle Size Fractions in the Central Amazon Predicted from Remotely Sensed Relief, Multispectral and Radar Data

Soils from the remote areas of the Amazon Rainforest in Brazil are poorly mapped due to the presence of dense forest and lack of access routes. The use of covariates derived from multispectral and radar remote sensors allows mapping large areas and has the potential to improve the accuracy of soil attribute maps. The objectives of this study were to: (a) evaluate the addition of relief, and vegetation covariates derived from multispectral images with distinct spatial and spectral resolutions (Landsat 8 and RapidEye) and L-band radar (ALOS PALSAR) for the prediction of soil organic carbon stock (CS) and particle size fractions; and (b) evaluate the performance of four geostatistical methods to map these soil properties. Overall, the results show that, even under forest coverage, the Normalized Difference Vegetation Index (NDVI) and ALOS PALSAR backscattering coefficient improved the accuracy of CS and subsurface clay content predictions. The NDVI derived from RapidEye sensor improved the prediction of CS using isotopic cokriging, while the NDVI derived from Landsat 8 and backscattering coefficient were selected to predict clay content at the subsurface using regression kriging (RK). The relative improvement of applying cokriging and RK over ordinary kriging were lower than 10%, indicating that further analyses are necessary to connect soil proxies (vegetation and relief types) with soil attributes.

Discovery or Extinction of New Scleroderma Species in Amazonia?

The Amazon Forest is a hotspot of biodiversity harboring an unknown number of undescribed taxa. Inventory studies are urgent, mainly in the areas most endangered by human activities such as extensive dam construction, where species could be in risk of extinction before being described and named. In 2015, intensive studies performed in a few locations in the Brazilian Amazon rainforest revealed three new species of the genus Scleroderma: S. anomalosporum, S. camassuense and S. duckei. The two first species were located in one of the many areas flooded by construction of hydroelectric dams throughout the Amazon; and the third in the Reserva Florestal Adolpho Ducke, a protected reverse by the INPA. The species were identified through morphology and molecular analyses of barcoding sequences (Internal Transcribed Spacer nrDNA). Scleroderma anomalosporum is characterized mainly by the smooth spores under LM in mature basidiomata (under SEM with small, unevenly distributed granules, a characteristic not observed in other species of the genus), the large size of the basidiomata, up to 120 mm diameter, and the stelliform dehiscence; S. camassuense mainly by the irregular to stellate dehiscence, the subreticulated spores and the bright sulfur-yellow colour, and Scleroderma duckei mainly by the verrucose exoperidium, stelliform dehiscence, and verrucose spores. Description, illustration and affinities with other species of the genus are provided.