Brazilian Forest Research Articles

ULTRASOUND FOR OVERCOMING DORMANCY OF FABACEAE SEEDS FROM BRAZILIAN DRY SEASONAL FOREST

The overcoming dormancy of Fabaceae seeds from the Brazilian Dry Seasonal Forest were realized with non-sustainable technologies (acid or physical treatments). Ultrasound waves can be a sustainable alternative and innovation to these technologies cited. Then, this research aims at the evaluation of ultrasound waves overcoming dormancy in seeds from Brazilian Dry Seasonal Forest. For this purpose, the following species were tested: Mimosa tenuiflora, Pityrocarpa moniliformis, Sesbania virgata, and Vachellia farnesiana . The seeds were previously immersed in distilled water for 24 hours before treatment, then divided into five treatments and submitted to 0, 90, 180, 270, or 360 seconds [25.0 ± 2.0ºC and 42 kHz frequency] and sown in the nursery. Variables of emergence and vigor in seeds and seedlings and descriptive statistics, ANOVA, and Pearson correlation were analyzed to analyze the data obtained. The use of ultrasound (frequency of 42 kHz) in different periods of exposition (0, 90, 180, 270, or 360 s) did not promote uniformity of emergence and vigor in seeds and seedlings of M. tenuiflora, P. moniliformis, S. virgata , and V. farnesiana . Other protocols based on this research can be carried out to improve the forest management of species.

SOIL FUNGI PROMOTE VIGOR IN SEEDS FROM BRAZILIAN DRY SEASONAL FOREST

The Brazilian Dry Seasonal Forest (Caatinga Biome) is poorly studied about possible interactions between seeds, seedlings, and Trichoderma harzianum strains to promote vegetal vigor in seedlings. So, this research aims to study the T. harzianum strain promotion of vigor in different species from Caatinga Biome in nursery. For assays, we used: Aspidosperma pyrifolium, Cnidoscolus quercifolius, Handroanthus impetiginosus, Pseudobombax marginatum , and Tabebuia aurea species and the T. harzianum IBLF 006 based-product-inoculant. We tested these assays in nursery conditions. T. harzianum solution (0.5% v/V) was used in the nursery assay (applied over soil after the sowing). For this research, we evaluated variables of vigor and germination and there was a control treatment (non-inoculated). About nursery assay results, there was a positive interaction for all species between seeds and seedlings and T. harzianum , except for T. aurea and C. quercifolius . For all species tested in this research, we suggest that other seed or soil treatments can be tested in environmental Caatinga Biome conditions to expand this knowledge about the interaction between Trichoderma harzianum and seedlings and seeds from Caatinga biome.

Recent Environmental Legislation in Brazil and the Impact on Cerrado Deforestation Rates

This study aims to relate the recent trajectory of Brazilian environmental policies with the last 20 years deforestation rates observed in the Cerrado through the PRODES-Cerrado monitoring initiative. The main hypothesis is that the improvement of environmental legislation in Brazil, mainly during the period between 2005 and 2012, influenced the decrease in deforestation rates. In addition, policies to control environmental compliance, such as the Rural Environmental Registry (CAR) also influenced the reduction of deforestation. In the early 2000s, there was a significant increase in public environmental policies and implementation of an environmental management structure with the creation of conservation, protection, and management agency for conservation units (ICMBio), the Brazilian Forest Service for the management of public forests and Rural Environment Registry (CAR). Comparing the annual deforestation rate, it was observed that between 2000 and 2005, when 12.60% of the Cerrado was deforested, the annual deforestation average rate was 2.52%. Between 2006 and 2012, the period that precedes the revision of the Forest Code, the total deforestation is equivalent to 7.98%, which results in an annual average rate of 1.33%. After the enactment of the new Forest Code, between 2013 and 2020, there was a deforestation of 7.03% of the Cerrado area, which is equivalent to a deforestation annual average rate of 1.00%. One of the positive aspects of the new legislation was the creation of CAR, which obliges rural landowners to make an environmental attributes declaration of their property, this program being the main environmental management tool created in Brazil recently. After CAR regulation in 2014, there was a decrease in deforestation from 10,904 km2 to 7905 km2 in 2020. On the other hand, since 2016, changes occurred in the political scenario that increased agribusiness influence and the rise of a more conservative agenda, which jeopardizes the future of environmental quality in Brazil (illustrated, for example, by the increased release of pesticides from 104 in 2010 to 493 in 2020). As the main conclusion of this research, we showed that the state’s commitment to environmental management can contribute to deforestation reduction. The regulation of programs such as CAR can also contribute to the reduction of deforestation since it is one more tool for monitoring and ensure compliance of environmental regularization and recovery vegetation programs. At the same time, is necessary to keep on monitoring deforestation once the influence of the agricultural lobby has gained strength.

The environment role in the incomplete reproductive cycle of Tropaeolum pentaphyllum Lam. (crem) in Brazilian Mixed Ombrophilous Forest: implications for conservation and cultivation

The environment role in the incomplete reproductive cycle of Tropaeolum pentaphyllum Lam. (crem) in Brazilian Mixed Ombrophilous Forest: implications for conservation and cultivation

Old‐growth structural attributes associated with the last giant subtropical conifers in South America

AbstractGiant Araucaria trees in Brazilian Atlantic forests today are rare but remain critically important for structuring these ecosystems, providing unique and rare habitat elements that can serve as points of reference for their management. Old‐growth Araucaria trees, with their complex crowns and big trunk cavities, supply more important ecological services than smaller trees with simple crowns. Forest ecology managers lack information on the old‐growth structures of Brazilian Araucaria forest, their ecological importance and their potential societal values and uses. In this study, we investigated old‐growth attributes of Araucaria angustifolia and relate their wide structural variability to ecological management goals. In this study, we used currently available data on the last large old Araucaria trees, as well as our own new records, from large trees of 1.6–3.2 m diameter in the Araucaria forests in southern Brazil. In order to quantify the structural attributes of these remnant trees, their main trunks, any reiterated canopy trunks and trunk cavities were measured for diameters, heights and volumes. These old‐growth trees had an average height of 38.4 m, and total tree volumes ranged from 21.5 to 106.6 m3. The biggest reiterated trunk was 1.1 m in diameter and 17 m long, which is larger than most adult Araucaria trees. Number of cavities and number of reiterated trunks were all significantly related to the diameters of these large remnant Araucaria trees; both features are absent in Araucaria <50 cm in diameter. The maximum diameter and average length of reiterated trunks were correlated with the number and size of trunk cavities. Commercial wood values and uses are limited for all trees with main trunk diameters exceeding 1.5 m due to large internal cavities—however, these rare, relictual old‐growth structures are of high ecological value for the local fauna and flora.

Legacy of harvesting methods on coppice-rotation Eucalyptus at experimental and operational scales

Coppice-rotation stands comprise 20 to 30% of the Eucalyptus forests in Brazil and understanding the factors influencing the production ecology of the coppice-rotation is fundamental to improving silvicultural prescriptions. We investigated the effect of harvesting method, stump height and stump cleaning on survival, uniformity, growth, above-ground biomass and light use efficiency in a short rotation of a highly productive E. grandis x E. urophylla clone at two scales in Brazil. At the field experiment scale, treatments were composed of harvesting techniques (Chainsaw and Feller Buncher), stump height (High and Low) and stump cleaning (No harvesting residues over the stump or with residues). The treatments strongly affected growth in height and volume, with less effect on diameter. The largest response came from harvesting method, with mechanized harvesting with a 33% lower mean annual increment (MAI, 33 m³ ha−1 y−1) than harvesting with the chainsaw (50 m³ ha−1 y−1). Stump height did not influence growth in chainsaw clear-cut, but low stumps after Feller Buncher harvesting reduced growth by 23% (30 m³ ha−1 y−1) compared with high stumps (36 m³ ha−1 y−1). Stumps cleaning increased survival only in the semi-mechanized harvest but did not result in a difference in yield. Leaf area index and light use efficiency at the end of rotation were impacted by the clear-cut method, with an average of 3.3 and 2.1 m² m−2, and 0.7 and 0.57 g MJ−1 for chainsaw and Feller Buncher clear cut, respectively. The percentage of stumps that remained intact, the uniformity among individuals, the light capture and the light use efficiency, presented a r² of 67%, 55%, 60% and 86% (p-value < 0.001), respectively. At the operational scale of 12 plantations, we measured MAI, uniformity and survival of the two harvesting methods, all with high stump height and no stump cleaning (current operational prescription). The reduction in coppice-rotation MAI from Feller Buncher harvesting was consistent with the experimental scale, but the difference in MAI (age 4 years) was not as large: 37 m³ ha−1 y−1 for the Feller Buncher harvest and 44 m³ ha−1 y−1 for chainsaw harvest. Harvesting with the Feller Buncher, lowered survival (88%, compared with to 96% with chainsaw harvest) and stand uniformity. Overall, the impacts of harvesting treatment were large enough to those silvicultural systems that include a coppice rotation need to carefully account for the costs and efficiencies of operations for harvesting the planted rotation with subsequent impacts on coppice survival and production.

Arbuscular Mycorrhizal Fungi and Soil Quality Indicators in Eucalyptus genotypes With Different Drought Tolerance Levels.

Silviculture has great importance worldwide, and the use of Eucalyptus species, which account for 75% of the local planted forest in Brazil, is one of the factors that contributes to the success of this activity in the country. Despite its adaptability, the yield of Eucalyptus is often affected by climate change, particularly water deficiency. Plants have developed strategies to mitigate water stress, for example, through their association with mycorrhizal fungi. The genus Eucalyptus, particularly in the plant domain, establishes symbioses with arbuscular mycorrhizal fungi (AMF) and ectomycorrhizal fungi (ECMF). The influence of Eucalyptus species on AMF and soil quality indicators is not well understood. Our aim was to conduct a preliminary evaluation of the various responses of soil AMF communities and soil nutrient dynamics in the presence of Eucalyptus species with different degrees of drought tolerance. A field experiment was established containing six Eucalyptus species, E. brassiana, E. camaldulensis, E. citriodora, E. cloeziana, E. grandis, and E. urophylla, all of which were planted in large plots. Soil and root samples were taken when the plants were 1.7 and 2.2 years old. We found that Eucalyptus species with low (E. grandis and E. urophylla) and intermediate drought tolerance (E. citriodora and E. cloeziana) showed stronger correlations with the AMF community than Eucalyptus species with high drought tolerance (E. brassiana and E. camaldulensis). Differences were also found between Eucalyptus species for AMF spore numbers and root colonization percentages, which was most evident for E. urophylla. The microbiological attributes found to be most responsive to Eucalyptus species were soil enzyme activities, AMF spore numbers, root colonization percentages, and fungal abundance. Soil organic carbon, phosphorus, potassium, zinc, copper, and iron were the main chemical drivers related to the soil AMF community structure in the presence of E. brassiana.

Two new diminutive species of Begonia (Begoniaceae) from the north coast of São Paulo State, Brazil

Two new species of Begonia (Begoniaceae) from the Atlantic Coastal Forest of Brazil are described and illustrated. Begonia atlantica and Begonia umbrosa are found living in rocky outcrops present on the slopes of Serra do Mar State Park, taxonomic affinities and provisional conservation assessments are also provided.

An evaluation of machine operator exposure to occupational noise during harvesting and extraction operations in Brazilian eucalyptus plantations

ABSTRACT Wood harvesting operations involve mechanized and semi-mechanized machines that expose operators to occupational noise. It was verified that the emission of occupational noise levels in the harvest of mechanized and semi-mechanized wood in Brazilian forests planted with eucalyptus were in compliance with Directive 2003/10/EC. Noise data were collected using two personal-use integrative meters. The lower action level of 80 dB(A), the upper action level of 85 dB(A) and the exposure limit of 87 dB(A) were evaluated. The results showed that 16.6% of the operators were exposed to thresholds above the lower action level, but remained below the upper level of 85 dB(A), 8.3% of the operators were exposed to occupational noise levels above the upper action level, without exceeding the exposure limit of 87 dB(A) and 25% of operators were exposed to levels above the exposure limit. Therefore, the occupational noise levels achieved when harvesting mechanized and semi-mechanized wood in forests planted with eucalyptus do not comply with Directive 2003/10/EC.

Remote detection and measurement of leaf-cutting ant nests using deep learning and an unmanned aerial vehicle

Leaf-cutting ants are the main group of insect pests in Brazilian forest plantations, and their nests can be visually identified in remotely sensed images. This study compares two distinct pattern recognition methodologies, each with different computational costs, for detecting and measuring leaf-cutting ant (LCA) nests in RGB images acquired by unmanned aerial vehicles (UAVs), aiming to develop an efficient detection system for day-to-day Eucalyptus plantation management. The first methodology (MLP) is based on traditional Multilayer Perceptron Neural Networks combined with the sliding window technique. The second methodology uses the new Convolutional Neural Networks YOLOv5 architecture, which is a deep learning approach applied to RGB imagery and requires more time and memory. For each input image, existing LCA nests were detected and measured based on their bounding box areas. Images were classified to detect the presence and measure the area of LCA nests. The quality of both methodologies were evaluated using accuracy, Kappa, sensitivity, specificity, and mean absolute percentage error (MAPE) metrics, considering training and test data sets. Performances of the YOLOv5 methodology were highly superior to those of the MLP methodology, with 98.45% accuracy using the YOLOv5 large architecture net and 0.49% MAPE in measuring the nests with YOLOv5s nets, whose performance was superior to the MLP results (65.45%), demonstrating high complexity in identifying the targets in the field. The YOLOv5 approach, applied to RGB images acquired by UAVs, shows great promise for precision monitoring of LCA nests, and thus can reduce and optimize insecticide use in forest plantation areas.

The economic value of the Brazilian Amazon rainforest ecosystem services: A meta-analysis of the Brazilian literature.

The main objective of this study is to assess the economic value of the Brazilian Amazon’s ecosystem services accruing to Brazilians based on a meta-analysis of the Brazilian valuation literature. Insight in these local values provides an important benchmark to demonstrate the importance of preserving the Brazilian Amazon forest. The review covers almost 30 years of Brazilian valuation research on the Amazon, published predominantly in Portuguese, highlighting a high degree of study and data heterogeneity. The estimated mean value of the provision of habitat for species, carbon sequestration, water regulation, recreation and ecotourism to local populations is about 410 USD/ha/year. The standard deviation is however high, reflecting a wide dispersion in the distribution of values. Between 50 and 70 percent of the variation in these values can be explained with the help of the estimated meta-regression models, resulting in considerable prediction errors when applying a within-sample resampling procedure. These findings demonstrate the need for a more robust, common ecosystem services accounting and valuation framework before these values can be scaled up and aggregated across the entire Brazilian Amazon.

Mapping Fire Susceptibility in the Brazilian Amazon Forests Using Multitemporal Remote Sensing and Time-Varying Unsupervised Anomaly Detection

The economic and environmental impacts of wildfires have leveraged the development of new technologies to prevent and reduce the occurrence of these devastating events. Indeed, identifying and mapping fire-susceptible areas arise as critical tasks, not only to pave the way for rapid responses to attenuate the fire spreading, but also to support emergency evacuation plans for the families affected by fire-related tragedies. Aiming at simultaneously mapping and measuring the risk of fires in the forest areas of Brazil’s Amazon, in this paper we combine multitemporal remote sensing, derivative spectral indices, and anomaly detection into a fully unsupervised methodology. We focus our analysis on recent forest fire events that occurred in the Brazilian Amazon by exploring multitemporal images acquired by both Landsat-8 Operational Land Imager and Modis sensors. We experimentally confirm that the current methodology is capable of predicting fire outbreaks immediately at posterior instants, which attests to the operational performance and applicability of our approach to preventing and mitigating the impact of fires in Brazilian forest regions.

Katydids (Orthoptera: Tettigoniidae) from the Iguau National Park, Brazil.

Katydids were surveyed in the Iguau National Park (ParNa Iguau), the largest preserve of the Interior Atlantic Forest in Brazil. Sampling was carried out in three different areas of the ParNa Iguau, including its two predominant phytophysiognomies (Seasonal Semidecidual Forest and Mixed Ombrophilous Forest), and consisted of diurnal and nocturnal active searching for katydids and also using light traps. After collected, specimens were reared until adulthood in order to record their calling songs. Almost a thousand katydids were collected, belonging to 89 species and five subfamilies. Phaneropterinae appeared as the most speciose subfamily (57 species), followed by Conocephalinae (22), Meconematinae and Pseudophyllinae, each one with four species, and Pterochrozinae (two species). Several species were recorded for the first time for the Paran State, for the South Region of Brazil, and also for the country. Calling songs of 34 species were recorded, 29 of them unknown to science. The description of the sound produced by species of some supraspecific taxa (e.g., Aniarae, Cosmophylla and Scaphurae) is here presented for the first time. Data reinforce the relevance of ParNa Iguau for the maintenance of thousands of species from different taxonomic groups and also highlight the catastrophic effects that continuous pressures and threats on the preserve, despite the successive attempts to downgrade this conservation unit, may have on the outstanding biodiversity that is harboured by ParNa Iguau.

Differential response of tree species from Brazilian tropical dry Forest (Caatinga) to phosphorus doses associated with organic matter

The availability of phosphorus (P) and organic matter in Chromic Luvisols, predominant in the Caatinga biome, is generally low and makes it difficult to reintroduce native plants in forest recovery projects. The objective was to evaluate the production of dry mass, accumulation a and use efficiency of P by three tree species native from Caatinga biome with application of doses of P and organic matter. This experiment was carried out in a greenhouse in a completely randomized design in a 2 × 3 × 5 factorial scheme, consisting of with two doses of organic matter (0 and 50 g kg−1), three species of plants (Tabebuia aurea (Silva Manso) Benth. & Hook.f. ex S Moore, Amburana cearensis, Allemão AC Smith and Caesalpinia ferrea Mart. Ex Tul.) and five doses of P (0, 50, 100, 150 and 200 mg dm−3). At 120 days after transplanting, concentrations of P available in the soil and leaf soluble P fractions increased linearly with the P doses. The availability of P in the soil and, consequently, the accumulation of soluble and total P in the plant tissues were greater with organic matter application. The studied species use different P compartmentalization strategies depending on their dry mass production capacity. Phosphate and or organic matter application is necessary in the initial growth phase of the studied species, notably T. aurea and C. ferrea. The dry mass of T. aurea was greater than that of C. ferrea and A. cearensis.

Local drivers of heterogeneity in a tropical forest: epiphytic tank bromeliads affect the availability of soil resources and conditions and indirectly affect the structure of seedling communities.

Environmental heterogeneity is a key component in explaining the megadiversity of tropical forests. Despite its importance, knowledge about local drivers of environmental heterogeneity remains a challenge for ecologists. In Neotropical forests, epiphytic tank bromeliads store large amounts of water and nutrients in the tree canopy, and their tank overflow may create nutrient-rich patches in the soil. However, the effects of this nutrient flux on environmental heterogeneity and plant community structure in the understory remain unexplored. In a Brazilian coastal sandy forest, we investigated the effects of the presence of epiphytic tank bromeliads on throughfall chemistry, soil chemistry, soil litter biomass, light, and seedling community structure. In the presence of epiphytic tank bromeliads, the throughfall nitrogen concentration increased twofold, the throughfall phosphorus concentration increased threefold, and the soil patches had a 3.96% higher pH, a 50% higher calcium concentration, and 11.88% less light. By altering the availability of soil resources and conditions, the presence of bromeliads partially shifted the available niche spaces for plant species and indirectly affected the structure of the seedling communities, decreasing their diversity, density, and biomass. For the first time, we showed that the presence of tank bromeliads in the canopy can create characteristic soil patches in the understory, affecting the structure of seedling communities via fertilization. Our results reveal a novel local driver of environmental heterogeneity, reinforcing and expanding the key role of tank bromeliads both in nutrient cycling and plant community structuring of Neotropical coastal sandy forests.

The productive autonomy of public forest-dwellers in the Amazon: two case studies of community timber management

Forest-dwellers in the Brazilian Amazon public forests share the management of the territory and natural resources with governmental agencies, subjecting themselves to State rules. This study aims to evaluate the perception of stakeholders about the autonomy of traditional communities to carry out community timber forest management (CFM) in two federal protected areas. A Swot analysis revealed mismatches in priorities among stakeholder groups (Communities, Government and Partners). Four autonomy parameters were evaluated by 111 stakeholders using a satisfaction questionnaire. Communities and Government had similar perceptions of the autonomy of communities to develop CFM, while Partners were pessimistic. Stakeholders showed greater satisfaction with communities’ social organization than with their business management ability. Licensing, operational tools and administrative knowledge were perceived as bottlenecks for community enterprises. Nevertheless, targeted public policies and a minimum regulatory requirement for CFM may guarantee community autonomy to maintain their way of life and make their forest enterprises viable.

Aquatic invertebrate diversity in tank bromeliads in an enclaved wet forest in Brazil’s semiarid region

ABSTRACT Phytotelmata bromeliads provide microhabitats for many organisms and maintain high aquatic diversity within Neotropical forests. However, they are more vulnerable to different environmental stressors that shape community structure. While most studies have been carried out in large rainforests, gaps remain about the bromeliad-dwelling community for the wettest points in the Caatinga domain (Brazilian semiarid region). Here, we investigated the influence of abiotic and temporal variables and bromeliad size on community structure between urban and forest sectors. Between 2014 and 2017, we randomly selected 20 urban and 40 forest bromeliads and compared functional groups of invertebrates for richness, abundance, and diversity. We recorded 41 morphospecies, especially Rotifera (19) and Insecta (13). Urban bromeliads exhibited higher richness of filter-feeder, while forest fragment bromeliads were dominated by predators, shredders, and gatherers. We did not observe differences in community structure regarding bromeliad size. However, the wetter period exhibited higher species richness, and higher diversity was associated with the highest rainfall. This study presents for the first time a list of aquatic microinvertebrate species and the influence of environmental parameters on the community structure associated with bromeliads of Caatinga. We have also expanded the list of species associated with phytotelmata in the Neotropical region.

Exposure to Occupational Noise

Physical agent noise can be considered one of the main disturbances that compromise the occupational health of self-propelled forest machine operators. We evaluated whether occupational noise levels emitted by self-propelled forest machines employed in the full tree system are in accordance with both the National Institute for Occupational Safety and Health and ISO 1999:2013 standards, while also proposing mitigating measures aimed at protecting the operators hearing. Seventeen operators, who performed wood harvesting operations in Eucalyptus forests in Brazil, were analyzed. Noise levels were collected in a daily shift of eight hours as recommended by the Acoustics – Determination of occupational noise exposure - Engineering method for full-day measurements (ISO 9612:2009). The standards adopted for the evaluation were the exposure action value of 80 dBA and the exposure limit of 85 dBA based on the National Institute for Occupational Safety and Health – NIOSH and on Acoustics – Estimation of noise-induced hearing loss (ISO 1999:2013) Directive 2003/10/EC. The operators were arranged in homogeneous groups according to the Acoustics recommendation – Determination of occupational noise exposure - Engineering method for full-day measurements (ISO 9612:2009), classified by the operations of felling, skidding of tree bundles and bucking. The results showed that 17 self-propelled forest machines exceeded the exposure action value of 80 dBA, of which 10 machines exceeded the exposure limit of 85 dBA. It was concluded that the levels of occupational noise emitted by self-propelled forest machines used in the full tree system are higher than those recommended by both standards, National Institute for Occupational Safety and Health and ISO 1999:2013. Therefore, the allocation of self-propelled forest machines to homogeneous groups allows inferring mitigation actions that protect operators' hearing. The correct use of hearing protectors during the daily workday provides hearing protection for operators in mechanized wood harvesting. Adoption of actions such as maintenance of cabin seals and mechanical components, breaks for fatigue relief, reduction of daily working hours and rotation of operators in different self-propelled forest machines can mitigate the damage to the occupational health of operators.

Riverine barrier hypothesis explains the structure of dung beetle communities in Brazilian Coastal Sand-dune forests

The Riverine Barrier Hypothesis (RBH) predicts that tropical rivers can be effective barriers to species dispersion, affecting different scales of biological organization, from genes to assemblages. We disentangled the latitudinal from the river presence effect to test the hypothesis that the Doce river mouth acted as a geographical, historical barrier for insects through North and South directions of the Brazilian coast, affecting the current community structure. We sampled dung beetle communities. In 16 Coastal Sand-dune Forest (“Restinga”) patches, across the Doce River Basin in the Brazilian coastline, nine through the South and seven through the North direction of the Doce River's mouth. We analyzed the relationship between the community composition and richness relative to the river (North and South regions) and latitude using linear modeling over a distance matrix (DistLM) approach. The latitude explained 17.74% of the total variation in dung beetle species composition, and the regional position relative to Doce River's mouth exhibited a significant effect (Pseudo F = 2.8479; p = 0.005) only after removing the latitudinal effect, here representing the habitat filtering. Both variables explained together with a total of 32.52% of the variability in dung beetles composition at coastal sand dune forests. The geographical position alone explained 48% of the richness difference between the North and South regions of the Doce River's mouth (Pseudo F = 16.534; p < 0.01). Meanwhile, the latitudinal position of the sites exhibited no significant relationship with species richness. Our findings highlight the role of Doce River as a biogeographical filter in the Doce river basin, while it represents the primary determinant of geographical segregation of the two key-species central to the dung beetle community structure.

A Monographic Conspectus of Myrcia sect. Calyptranthes (Myrtaceae) from South and Central America

Myrcia DC. sect. Calyptranthes (Sw.) A. R. Lourenço &amp; E. Lucas is a section of the Neotropical genus Myrcia with ca. 260 known species. This paper provides a taxonomic revision of 89 species occurring across South and Central America, including the Amazon, Andes, Guiana Shield, and Mesoamerica, and extending into the Caribbean archipelago, but not including those previously treated from the Atlantic Forest of Brazil. The treatment includes an identification key, informal taxonomic groupings and notes, geographic distribution information, and extinction risk assessments. Figures illustrating key morphological characters of the genus are provided including common leaf, flower bud, and inflorescence arrangements. Ten new synonyms, eight new lectotypes, and four new combinations are proposed, and a key to treated species is supplied.