Forest In Northeast Brazil Research Articles

Aridity and chronic anthropogenic disturbances cause a taxonomic, functional, and phylogenetic homogenization of ant communities in a Caatinga dry forest

Chronic anthropogenic disturbances (chronic disturbances) and climate change can eliminate sensitive species and support the proliferation of disturbance-adapted ones leading native communities to biotic homogenization. We investigate the individual and interactive effects of increasing chronic disturbances and aridity on the biotic homogenization of ant communities in a Caatinga dry forest in northeast Brazil. Ant communities were recorded across 20 forest stands covering gradients of annual rainfall and chronic disturbances (wood extraction, people pressure, and grazing pressure) intensity. Ant communities were described by adopting taxonomic, functional, and phylogenetic attributes. We collected 71 species (24 genera and 7 subfamilies). Aridity-driven reductions in beta diversity were stronger (about 73 %) than chronic disturbance-driven reductions (27 %) for all (but phylogenetic) biodiversity dimensions. Chronic disturbance-driven reduction in beta diversity was more evident via wood extraction than via people and grazing pressure. Intriguing interactive effects of chronic disturbance and aridity were observed for all biodiversity dimensions. Increased chronic disturbances led to slight increases in beta diversity in drier forest stands, probably due to spatial heterogeneity in aridity and chronic disturbance sources distribution. Results suggest that (1) aridity and chronic disturbance represent key drivers of community organization at the landscape scale, (2) chronic disturbance and aridity pose isolated and interactive effects, but aridity plays a major role, and (3) both community-level homogenization or divergence can emerge but in the extreme conditions ant communities converge taxonomically, functionally, and phylogenetically.

Reproductive functional organization of woody plant assemblages along regeneration in a Caatinga dry forest

Tropical forest regeneration across old fields has been mainly described as a predictable sequence of functional plant assemblages in response to environmental filtering. However, the way plant reproductive diversity is organized along forest regeneration and how the reproductive profile of woody flora may impact regeneration have been poorly investigated. This paper examines the organization of plant assemblages throughout the regeneration of a Caatinga dry forest in the context of slash-and-burn agriculture with a focus on reproductive plant traits and strategies. We hypothesized a recovery and directional changes in specialist reproductive traits/strategies along forest regeneration but with aridity and chronic anthropogenic disturbances posing contrary forces to this recovery process. This study was carried out in a human-modified landscape of Caatinga dry forest in northeast Brazil. We compiled information on woody plant assemblages inhabiting a forest chronosequence consisting of 28 forest stands of varying age: 14 regenerating (4–50-yr old) and 14 old-growth forests. Woody plant assemblages along forest regeneration had higher occurrence of specialized traits and strategies, such as pollination by vertebrates (16.6%) and dispersion by animals (47.8%). Regenerating forest stands exhibited a higher occurrence of species with specialized floral size (19%) and pollination by vertebrates (26.5%) as compared to old-growth forests. Regenerating forest stands also supported a higher (30%) functional diversity of reproductive traits than old-growth stands. Biomass, aridity, and chronic anthropogenic disturbances affected a myriad of traits/strategies: pollination by birds and animal dispersion increased with increases in biomass while total functional diversity responded negatively; pollination by Sphingids and beetles negatively responded to aridity, while very large fruit size species negatively responded to chronic anthropogenic disturbances. Both forest biomass and aridity correlated negatively with reproductive trait diversity. The Caatinga dry forest regeneration suggests high resilience, no directional/predictable changes (although regenerating vs. old-growth differ in some traits) and aridity imposed to the successional mosaics as a driver. This pattern probably emerges conditioned by the reproductive traits posed by the plant species able to thrive in such stressful environments, including those species that persist through the entire regeneration process, i.e., the regeneration process is marked by high complexity and low predictive power. Although rapid recovery represents good news, the plant-assemblage reproductive profile imposed by disturbance-adapted species may drastically alter resource availability for a myriad of plant attendants (e.g., pollinators and thief) and, consequently, the complex/diverse plant-animal interactions typical of dry forests. This working hypothesis has both theoretical and applied implications in the context of dry forest regeneration in human-modified landscapes.

Ecology of Phrynops geoffroanus and Mesoclemmys tuberculata (Testudines: Chelidae) in Climatically Distinct Areas of the Semi-Arid Caatinga and Atlantic Forest in Northeast Brazil

Ecology of Phrynops geoffroanus and Mesoclemmys tuberculata (Testudines: Chelidae) in Climatically Distinct Areas of the Semi-Arid Caatinga and Atlantic Forest in Northeast Brazil

Non-negligible role of dead organic matter in a rainforest remnant in Northeast Brazil

Abstract Dead organic matter represents an essential reservoir of carbon, especially that allocated in standing dead trees, coarse woody debris, and fine litter, playing a pivotal role in nutrient cycling and habitat provisioning. However, necromass is frequently disregarded in forest assessments. Here, we aimed to perform the first assessment of multiple necromass compartments in the Atlantic Forest of Northeast Brazil, providing a basis for future integrative studies related to necromass in this region. We registered 17 standing dead trees in 0.5 hectare and 239 logs of coarse woody debris. Necromass had 3.9 Mg.ha-1 of standing dead trees, 54.24 Mg.ha-1 of coarse woody debris and 7.2 Mg.ha-1 of litter. We indicate that standing dead trees and coarse debris were mostly in the intermediate and final stages of decomposition. Leaves were the dominant component of litter, and drier months had more litterfall. Finally, we highlight that assessing standing dead trees and coarse woody debris adds 25.6% on top of aboveground tree mass, improving information about organic matter storage in rainforest ecosystems. Our findings emphasize that the necromass compartment must be considered in forest assessments, also including small pieces of coarse woody debris, which could inform better practices of forest management.

Plant functional types broadly describe water use strategies in the Caatinga, a seasonally dry tropical forest in northeast Brazil.

In seasonally dry tropical forests, plant functional type can be classified as deciduous low wood density, deciduous high wood density, or evergreen high wood density species. While deciduousness is often associated with drought‐avoidance and low wood density is often associated with tissue water storage, the degree to which these functional types may correspond to diverging and unique water use strategies has not been extensively tested.We examined (a) tolerance to water stress, measured by predawn and mid‐day leaf water potential; (b) water use efficiency, measured via foliar δ13C; and (c) access to soil water, measured via stem water δ18O.We found that deciduous low wood density species maintain high leaf water potential and low water use efficiency. Deciduous high wood density species have lower leaf water potential and variable water use efficiency. Both groups rely on shallow soil water. Evergreen high wood density species have low leaf water potential, higher water use efficiency, and access alternative water sources. These findings indicate that deciduous low wood density species are drought avoiders, with a specialized strategy for storing root and stem water. Deciduous high wood density species are moderately drought tolerant, and evergreen high wood density species are the most drought tolerant group.Synthesis. Our results broadly support the plant functional type framework as a way to understand water use strategies, but also highlight species‐level differences.

Carbon in forest species of the Atlantic Forest as an indicator of stocks and quality

The objective is to quantify the carbon content (C) of the reservoirs of plant biomass of different species in a fragment of the Atlantic Forest in Northeast Brazil. Ten species of high absolute density were selected. We sampled biomass from the leaf and wood compartments of each species to determine the C content. There was a difference in leaf C levels between species. The C content in leaves of species varied between 451.4 and 456.7 g kg-1. The C content of the wood of species varied between 451.7 and 456.8 g kg-1. The group formed by the families Burseraceae, Moraceae, and Sapotaceae showed higher average levels of C in leaves. The Burseraceae family had the highest average C content in the species' wood. The use of a pre-established carbon content (500 g kg-1) may generate inconsistent estimates higher than the real values for the species and families in an Atlantic Forest environment. We suggest that C stock estimates use specific levels for species and/or families, contributing to a more realistic estimate of C storage patterns in the shoot biomass of Atlantic Forest species.Keywords: Carbon concentration; Carbon sequestration; Tropical Rainforest.

Description of a new species of Corixidea from Brazil (Heteroptera: Dipsocoromorpha: Schizopteridae)

ABSTRACT The minute litter bug genus Corixidea Reuter, 1891 currently comprises nine valid American species. Herein, we describe Corixidea quaresmai sp. nov. from one of the last remaining remnants of Atlantic Forest in northeast Brazil. The new species is characterized by the distal extension of the anophoric process parallel and close to the left lateral margin of the tergites, and the elongated process of tergum 8, with a pectinate distal half and a filiform tip. We provide diagnosis, images of habitus and male genitalia.

Anurofauna of a remnant of Atlantic Forest in northeast Brazil

Studies on spatial occupation are fundamental to understand amphibian communities. The aim of this study was to record information on the spatial distribution of anurans in the Tejipió forest, state of Pernambuco, Northeastern Brazil. Fieldwork was carried out weekly between October 2011 and April 2012, with daytime and night-time excursions for time-constrained active searching, in forested and open areas, military construction area and water bodies. Pitfall traps and accidental sightings were also used as alternative collection methods. Data were used to calculate richness, rarefaction curves and richness estimators. A total of 21 species were recorded, distributed in six families: Bufonidae (2 spp.); Craugastoridae (1 sp.); Hylidae (8 spp.); Leptodactylidae (8 spp.); Microhylidae (1 sp.) and Phyllomedusidae (1 sp.). Only the speciesRhinella jimiwas found occupying all sampled habitats in the research area.Adenomera hylaedactylaandPristimantis ramagiideserve special care in the area because they are specialists, occupying a smaller number of habitats and microhabitats. The community of anurans of the Tejipió forest is similar to those recorded in other areas of the Atlantic Forest at the Pernambuco State, and its knowledge is essential as a basis for conservation of the area. The gradual recovery of this Atlantic Forest remnant would favor the recolonization of fauna and flora and the conservation of local biodiversity.

Land-use and coverage in the structure of the landscape in a Tropical Dry Forest in northeast Brazil

Landscape Ecology using GIS is applied to understand the effects of forest fragmentation and makes it feasible mainly for extensive areas, through the possibility of analyzing both the variety of units that compose it in time. This study aims to analyze the land use and coverage of tropical dry forests and to characterize their landscape structure in an area of the municipality of Floresta, Pernambuco, Brazil, in order to understand how the landscape configuration can influence the conservation. Orbital images were used from LANDSAT, and the classification was performed in the QGIS 2.18 software using the Maximum Likelihood methodification, for the years of 2007 and 2017. A circular buffer was incorporated around the area of study to analyze the structural patterns in the context of the landscape. Five thematic classes were used: dense vegetation, sparse vegetation, exposed soil, grassland, and water. The metrics were obtained through the Patch Analyst tool only to the class of dense vegetation. It is noted that much of the dense vegetation has become sparse. There was a reduction of exposed soil and an increase in grassland areas, which may indicate a regeneration process of the vegetation. The fragments of dense vegetation with more substantial dimensions are on constant exploratory actions and are the most affected with the reduction of size. Furthermore, climatic factors, periods of drought, and the presence of livestock may also affect the fragmentation of dense vegetation patches. Therefore, the landscape became heterogeneous, and a tendency was observed to increase the fragmentation, mainly in the more significant spots.

Genetic diversity in forest populations from conservation units in the Atlantic Rainforest in northeast Brazil

Fragmentation leads to changes in the size and dynamics of forest populations. Studies of genetic diversity support strategies for preserving the genetic resources, and the data to date for the Atlantic Forest in northeast Brazil is scarce. Thus, the objective of this study was to evaluate the genetic diversity of Protium heptaphyllum (Burseraceae) tree species in three populations. We sampled 64 individuals in this study, for which seven primers used generated 90 loci, with 93% being polymorphic. The average number of alleles was 1.59, the effective number of alleles was 1.34, Nei’s genetic diversity was 0.20, and the Shannon index was 0.30. AMOVA indicated higher genetic variation among individuals within populations than among populations. Bayesian analysis revealed the existence of two distinct genetic groups, in which the MAC (Macaiba) population was the most differentiated. Genetic bottleneck tests indicated that all populations presented significant reductions in the population size. In situ conservation strategies must be adequately maintained considering the current isolation of studied populations, the genetic bottleneck, and the low average genetic diversity detected. Also, further recovery of degraded areas in the vicinity and ex situ conservation are recommended.

Phylogenetic signal in leaf-cutting ant diet in the fragmented Atlantic rain forest

AbstractLeaf-cutting ants are dominant herbivores in Neotropical rain forests, and their colony densities increase in disturbed habitats such as forest edges. However, while it is well-established that leaf-cutting ants profit from changes to the food-plant community, the phylogenetic dimension of this ant–plant interaction remains poorly understood in fragmented forests. We studied diet composition of Atta cephalotes in the edge and interior of Atlantic forest in north-east Brazil (8°30′S, 35°50′W). We applied phylogenetic signal analysis to investigate the diet across plant lineages and performed phylogenetic generalized linear models to analyse the diet in both habitats. We found a phylogenetic signal in diet and in leaf mechanical resistance, which means that A. cephalotes selects closely related food plants with less resistant leaves. Most preferred species belong to Malpighiales, Rubiaceae and Melastomataceae. We also found that irrespective of phylogeny, ants select food plants with less resistant leaves, both in edge and interior. However, ants choose more abundant plants only in edges. High abundance of optimal diet facilitates foraging in forest edges and explains why colony densities increase in disturbed habitats. Finally, by favouring or disfavouring specific clades, leaf-cutting ants contribute to changes in the phylogenetic structure of tropical rain forests, e.g. phylogenetic impoverishment.

Spatio-temporal variation and the use of host body surface by ectoparasites of the chelonians Phrynops geoffroanus and Mesoclemmys tuberculata in areas of the Caatinga and Atlantic Forest in northeast Brazil.

Ectoparasites such as hematophagous leeches and monogeneans are common in chelonians, occupying different parts of the body. Thus, the present study aimed to identify and describe the fauna of ectoparasites that infest Phrynops geoffroanus and Mesoclemmys tuberculata to evaluate the effect of host conditions and seasonality (dry and rainy season) on the abundance and composition of ectoparasites. We verified the presence of ectoparasites in 73.2% of the examined turtles, with four species of leeches belonging to Glossiphoniidae, Haementeria brasiliensis sensu Cordero, 1937, Helobdella cf. adiastola, Haementeria sp1., and Haementeria sp2., and one monogenean Polystomatidae, Polystomoides brasiliensis. For both chelonians, we observed a significant difference in the abundance of ectoparasites in relation to sex, biome, and season, which was unrelated to length and mass. Leeches were more frequent in the cavities of the hind limbs in P. geoffroanus, and the anterior limbs of M. tuberculata. The general spatial niche overlap of ectoparasites was high, except for that of the monogenean P. brasiliensis, which did not overlap with those of other leech species. The present study is the first report of the presence of H. brasiliensis and P. brasiliensis parasitizing M. tuberculata, and Helobdella cf. adiastola in a phoretic relationship with P. geoffroanus and M. tuberculata. Finally, the differences in infestation levels may reflect ecological factors, differences in behavioral patterns of the hosts, and different anthropic alterations suffered in the Caatinga and Atlantic Forest biomes.

Phylogenetic Placement of New Species with Fused Calyx Reveals Homoplastic Character in Eugenia (Myrtaceae)

Abstract—The hyper-diverse Eugenia with ca. 1050 species currently includes Calycorectes, which fits the morphological delimitation of the latter except its calyx lobes are fused in the bud and tear at anthesis. Previous phylogenetic reconstruction demonstrates a single evolutionary event of calyx fusion in Eugenia. A new species, Eugenia petaloidea, found in remnants of submontane Atlantic Forest in northeast Brazil is morphologically unique with two external fused calyx lobes that split at anthesis and two internal free and petaloid calyx lobes. Only a few other Eugenia species share this condition, and Eugenia petaloidea can be distinguished from those by the externally glabrous hypanthium. The phylogenetic placement of Eugenia petaloidea based on three DNA markers (ITS, ETS, and psbA-trnH) indicates that this is the second clade of Eugenia known to have a fused calyx, indicating fusion of the calyx to be a homoplastic condition. The new species is here described, illustrated, and assessed according to IUCN criteria.

Competition during sugarcane crop raiding by blond capuchin monkeys (Sapajus flavius).

Shifting to fallback food (FBF) consumption and crop raiding are behavioral adjustments that support primates' ability to endure in human-altered habitats. Nutritional models predict that the consumption of preferred foods leads to increased competition, while consumption of staple fallback foods results in decreased competition. We analyzed the competitive regime faced by individuals in a group of 133 blond capuchin monkeys (Sapajus flavius), an endangered species that inhabits a 270-ha fragment of Atlantic forest in northeast Brazil. During the study year, quantitative analyses show that fruits were a preferred food, while sugarcane was used as a staple FBF. As predicted by primate fallback foraging models, the consumption of sugarcane helped the group to survive in this fragment by providing these animals with half of the food they consumed throughout the year. Contrary to predictions, group dispersion increased with greater fruit abundance, while direct competition peaked during the consumption of sugarcane. We suggest that, although it is abundant and scattered in the area, the long handling time required to process sugarcane before consumption facilitates the direct competition. Overall, the pattern found indicates that consumption of a staple FBF does not directly translate into decreased competition and increased stability of social groups in forest fragments.

Food-sharing behaviour within a group of free-living Endangered Coimbra-Filho’s titi monkeys

Socioecological studies related to food-sharing behaviours in titi monkeys are scarce, with no such reports for the Endangered Coimbra-Filho’s titi monkey, Callicebus coimbrai. We aimed to describe the pattern of food-sharing behaviours during monitoring (444 h) of a wild group of Coimbra-Filho’s titi monkeys inhabiting a fragment of Atlantic forest in Northeast Brazil. We reported 43 food-sharing events (23 food-begging and 20 transfer attempt events). For the food-begging events, infants were the main beggars (74 %) while adult males were the main possessors (48 %). High-quality foods were more shared between related and unrelated individuals. Infants were the most successful beggars, receiving most of the high-quality food. Coimbra-Filho’s titi monkeys did not require any special skills to access the high-quality or easy-to-process food items related to the food-sharing events, suggesting that food sharing in these monkeys is linked to the kin selection and sharing-under-pressure hypotheses.

Pollination partial recovery across monospecific plantations of a native tree (Inga vera, Leguminosae) in the Atlantic forest: Lessons for restoration

In the last decades several approaches have been adopted for tropical assisted forest restoration from monospecific plantations to the establishment of highly-diverse tree stands. However, the long-term viability of restored forest and their capacity to provide the required services demand continuous evaluation to guide future initiatives. We aimed to evaluate the existence of pollination recovery in monospecific tree plantations in a hyper fragmented landscape of the Atlantic forest in northeast Brazil. By using Inga vera as a model species, we compared several relevant aspects relative to tree reproduction such as reproductive phenology, floral structures, nectar consumption, fruit- and seed-set, between monospecific plantations and native conspecific populations. Populations of I. vera from both native forest stands and planted areas flowered in overlapping periods in the dry season, while fruiting occurred at the beginning of the rainy season. Flowers of planted populations were significantly larger (11% in the size of the calyx, corolla and androecium – staminal tube and filaments) relative to natural populations. Flowers of both planted and natural populations secrete ca. 46 μl of nectar with concentration of 20.2% and 45.8 mg of sugars throughout the anthesis. However, the average volume of nectar consumed by visitors per flower in planted populations was 30% lower than in natural populations. The frequency of pistils with pollen tubes and the average number of seeds per fruit were similar between natural and planted populations. Nevertheless, surprisingly, the natural fruit set was 49% lower in planted relative to natural populations. Lower consumption of nectar and natural fruit set in planted populations of I. vera, in relation to the natural populations, indicate a partial recovery of the pollination process through the practice of planting single species of a tree in clusters of individuals. Our results add some doubts about the long-term viability and the ability of monospecific plantations in delivering services such as increased pollination capacity in human-modified landscapes.

Management practices may lead to loss of arbuscular mycorrhizal fungal diversity in protected areas of the Brazilian Atlantic Forest

Abstract The symbiotic arbuscular mycorrhizal (AM) fungi are among the ecologically most significant organisms in terrestrial ecosystems, but little is known about how soil AM fungal community composition responds to conservation management and different degrees of human impact on natural ecosystems. The objective of this study was to evaluate effects of the management practices on the AM fungi community structure in protected areas of the Atlantic Forest in Northeast Brazil. During two seasons we assessed AM fungal diversity and mycorrhizal root colonization status in five strict-protected and five sustainable-use areas along a 900 km transect. The sampling effort was sufficient to recover more than 85% of the AM fungal species present in the protected areas. Fifty-six AM fungal species and morphotypes were identified. Most species belonged to Glomerales and Gigasporales, but all orders of Glomeromycotina were registered. Species diversity and mycorrhizal colonization were significantly higher in the strict-protection management areas, though the areas had the same richness and spore density. Seasonality and spatial distances did not affect the AM fungal community composition. Our results show that the conservation management, vegetation and soil characteristics are important local factors influencing AM fungal communities. This work provides a better understanding of AM fungal community structure in natural ecosystems and provides insight into distribution patterns at a broad landscape scale.

Comparative Study of the Physicochemical Properties of FAME from Seed Oils of Some Native Species of Brazilian Atlantic Forest

AbstractThe rapid decline in fossil fuel reserves in the world, rising oil prices, and growing concerns about the increase in pollutant gas emissions from this type of energy, have led to the exploration of new energy sources for the production of alternative fuels. The use of vegetable oils as a low‐cost raw material for biodiesel production is an effective way to reduce biodiesel costs. This paper reports on the production and biodiesel properties of the seed oils of six native species belonging to different families of plants from the Atlantic Forest in northeast Brazil. The results are compared with those obtained from traditional crops such as soybean and olive. The relative oil content of the seeds ranged from 31.5 to 67.4 %, while the biodiesel yield from these oils ranged from 93.2 to 97.6 wt%. The fatty acid composition is mainly constituted of oleic acid in three species (Cissampelos andromorpha, Rauwolfia grandiflora, and Tabernaemontana flavicans), eicosenoic acid in two species (Serjania caracasana and Serjania salzmanniana) and palmitic acid in Protium heptaphyllum. The physicochemical parameters of oil (density, viscosity, % FFA, and % of linolenic acid) and biodiesel (density, viscosity, acid number, copper strip corrosion, flash point, sulfur content, sulfated ash, water, oxidative stability, free and total glycerin) were in agreement with ASTM 6751 and EN 14214 standards. The fatty acid composition, biodiesel yield, oil, and biodiesel properties of the six native species studied demonstrate the high potential for producing alternative fuel in conventional diesel engines.

Distribution and conservation of three important bird groups of the Atlantic Forest in north-east Brazil.

The Pernambuco Endemism Center in north-east Brazil has the most fragmented forest cover and the largest number of threatened birds of the whole Atlantic Forest. We analyzed the distribution of three groups of bird species: forest-dependent, endemic and/or threatened using the interpolation method of Inverse Distance Weighting. We also checked the concentration of these birds in protected and unprotected areas, suggesting new sites that need to be protected. The richness concentration of forest-dependent, endemic and/or threatened birds in 123 sites were analysed. There was a greater concentration of the three groups in north Alagoas, south and north Pernambuco, and north and west Paraíba. The distribution of the three groups was almost regular in different vegetation types, although a lower concentration was found in the pioneer formation. There was a greater concentration of birds from all three groups between Pernambuco and Alagoas, and this must be due to the presence of more forest fragments with better structure and vegetation heterogeneity. The protected and unprotected areas hosted important records of endemic and/or threatened birds. We suggested some important places for implementation of new protected areas due to the larger concentrations of the target birds and because they are located within the boundaries of the Important Bird Areas.

Chronic anthropogenic disturbance causes homogenization of plant and ant communities in the Brazilian Caatinga

Although chronic anthropogenic disturbance (CAD) represents a significant threat to the integrity of tropical biotas, few efforts have been made to understand its impacts. We address the effects of CAD on plant and ant communities in the Caatinga, a seasonally dry tropical forest in northeast Brazil. Both taxa were recorded across 25 0.1-ha plots within a 220-km2 landscape dominated by old-growth vegetation exposed to human activities. CAD was measured indirectly via a disturbance index, which was calculated from proxies of human disturbance such as plot distance to roads and villages, and density of people and livestock. Plant and ant abundance was not correlated to the CAD index. However, CAD had negative, positive or neutral effects on species diversity, depending upon diversity measure, taxa and soil type; e.g. plants were more negatively affected than ants. Furthermore, several plant and ant species exhibited higher abundance in the most disturbed vegetation patches while some exhibited lower abundance. Species-level responses resulted in taxonomic responses at the community level and increments in cross-plot species similarity as CAD increased. Our results indicate that: (1) CAD affects several community-level attributes, but with differing intensities; (2) community-level effects can be either positive or negative, and effects are soil dependent; (3) plants are more negatively affected than ants; (4) some species benefit, while others are negatively affected by CAD; and (5) by affecting the abundance and occurrence of particular species, CAD causes biotic homogenization towards the higher end of the disturbance gradient.