Seasonal Semideciduous Forest Research Articles

Uncovering the rich amphibian fauna of two semideciduous forest fragments in southwestern Bahia, Brazil

Fauna inventories reduce biodiversity knowledge gaps by providing comprehensive data on species distribution, richness, and abundance. Furthermore, they identify undocumented species and enhance understanding of ecosystem dynamics and conservation needs. The richness and abundance of amphibian species were studied in two Semideciduous Seasonal Forest areas in the municipalities of Potiraguá (Serra Azul) and Itarantim (Serra do Mandim) in southwestern Bahia, Brazil. Active visual and acoustic surveys were conducted in 24 forest interior transects, two stream transects, and two permanent ponds investigated in the study area. Opportunistic encounters during team movements were also recorded. The richness was 46 amphibian species distributed in 14 families and 26 genera. Approximately half of the species were shared between the two areas, while 11 species were exclusive to Serra Azul and another nine were found only in Serra do Mandim. Cluster analysis for 42 locations in Atlantic Forest, Caatinga, and Cerrado, in a presence/absence matrix with 216 species, revealed that the composition of the amphibians found in Serra do Mandim and Serra Azul is similar to other sampled locations in the northeastern region of Minas Gerais, close to the study site, which are considered transitional between the Atlantic Forest and the Caatinga. Our results demonstrate that the remaining forest fragments in the region, although small and isolated, still sustain a high richness of amphibians with species restricted to the Atlantic Forest and Bahia, such as Bahius bilineatus, Ololygon strigilata, Aplastodiscus weygoldti and Vitreorana eurygnatha, and others considered typical of the Caatinga, such as Leptodactylus troglodytes and Physalaemus cicada. Additionally, we sampled potential new species, filled occurrence gaps, and expanded the geographical range of Pseudis fusca.

Using biodiversity databases to assess vascular plant diversity in Protected Areas: a case study of Parque Estadual do Forno Grande, Brazil

The Parque Estadual do Forno Grande is a fully protected area in the southern Espírito Santo State, Brazil. It belongs to the Atlantic Forest domain, with predominantly dense, ombrophilous, seasonal semi-deciduous forests and herbaceous/shrubby vegetation on rock outcrops. The area is recognised as highly important for conservation, designated as a priority biological area for protecting the Atlantic Forest's biodiversity. Although the importance of Protected Areas in conserving the Atlantic Forest biodiversity is unquestionable, it is crucial to understand the floristic patterns within these regions to develop effective conservation strategies. We utilised national online databases to compile species lists containing relevant information about their biodiversity. The updated list of vascular plants recorded in the Parque Estadual do Forno Grande is available in the “Catálogo de Plantas das Unidades de Conservação do Brasil” and it is presented here with further information on richness, endemism and conservation status. The Parque Estadual do Forno Grande harbours 958 species of vascular plants, of which 79.2% are angiosperms, 18.4% are ferns and 2.4% are lycophytes. Amongst these species, 44% are endemic to the Atlantic Forest. There are 58 threatened species, of which six are Critically Endangered, 39 are Endangered and 13 are Vulnerable. Amongst the threatened species, 51 are endemic to the Atlantic Forest. The number of records and the species richness in this area are notably high for Atlantic Forest standards. Our findings suggest that floristic inventories of Brazilian Protected Areas are a key contribution to the general perception of how much we still do not know about our flora. It also highlights the necessity of supporting floristic surveys in poorly-known areas, especially those remaining as forest remnants.

Tree architecture and leaf morphometry of Qualea grandiflora Mart. (Vochysiaceae) in a fragment of dry forest and pasture in the State of Goiás, Brazil

Investigating the functional traits of plant communities is extremely important for conserving habitats and plant species. This study aimed to evaluate the tree architecture and leaf morphometry of Qualea grandiflora (Vochysiaceae) in a fragment of semideciduous dry forest and pasture in the Boa Esperança settlement, municipality of Piracanjuba, State of Goiás, Brazil. Environmental, tree architecture, and foliar morphometry data were collected for seven trees in the semideciduous dry forest and five in the pasture area. We used the Shapiro-Wilk test to assess the normality of the collected data. The student t-test was used to compare the means of the functional traits between the two environments (forest and pasture). The average value of canopy cover was 85% for the semideciduous dry forest and 0% for the pasture. The mean values for leaf length and width were lower in the pasture. There was no significant difference in the petiole length in the two evaluated environments and for none of the functional traits related to the tree architecture. However, individuals of Qualea grandiflora grow better in the seasonal semideciduous dry forest, probably as a response to less stressful environmental conditions for this species. Thus, for sustainable exploitation by the local community, it is recommended that the tree matrices be chosen within the semideciduous dry forest area.

Waterline distance effects in the recovery of forest structure and soil organic matter 12 years after restoration

Efforts to restore tropical forests can result in large unpredictability in their trajectories, mainly due to spatial variation in abiotic conditions and plant resource availability. With the construction of a small hydroelectric power plant, a 70-ha forest restoration was conducted in 2008 within the boundaries of seasonal semideciduous forest in southeastern Brazil. This study described the spatial variation of the restored ecosystem after 12 years by simultaneously evaluating the direct influences of distance from the water body (waterline distance) and soil moisture, and the indirect influence of these factors mediated by the forest structure on accumulated litter and soil organic matter (SOM). These effects were estimated in the area under restoration and in forest remnants (considered as reference sites) (Model A), or in the area under restoration alone (Model B). Data on forest structure included density of individuals, total basal area, tree average diameter, average trunk volume index and stratification. Tree density decreased with increasing waterline distance both in the restoration area and in the forest remnants. Consequently, the sites closest to the reservoir formed denser and more stratified forests. Waterline distance and soil moisture content were correlated with each other, but each variable had independent effects of on the amount of litter and SOM. Wetter sites with denser and more stratified forest had greater amounts of accumulated litter and soil organic matter, but only in Model A, which included both the restored area and the forest remnants. In addition, higher basal area values contributed weakly to greater amounts of accumulated litter. Thus, our study suggests that the trajectory and speed of recovery of some ecosystem processes were determined by the waterline distance and soil moisture. Furthermore, the restoration implementation in the period of just 12 years was sufficient to detect the effect of these actions on the litter accumulation and a substantial increase in the amount of soil organic matter.

Lianas in tropical dry seasonal forests have a high hydraulic efficiency but not always a higher embolism resistance than lianas in rainforests.

Lianas have higher relative abundance and biomass in drier seasonal forests than in rainforests, but whether this difference is associated with their hydraulic strategies is unclear. Here, we investigate whether lianas of seasonally dry forests are safer and more efficient in water transport than rainforest lianas, explaining patterns of liana abundance. We measured hydraulic traits on five pairs of congeneric lianas of the tribe Bignonieae in two contrasting forest sites: the wet 'Dense Ombrophilous Forest' in Central Amazonia (~2 dry months) and the drier 'Semideciduous Seasonal Forest' in the inland Atlantic Forest (~6 dry months). We also gathered a broader database, including 197 trees and 58 liana species from different tropical forests, to compare hydraulic safety between habits and forest types. Bignonieae lianas from both forests had high and similar hydraulic efficiency but exhibited variability in resistance to embolism across forest types when phylogenetic relationships were taken into account. Three genera had higher hydraulic safety in the seasonal forest than in the rainforest, but species across both forests had similar positive hydraulic safety margins despite lower predawn water potential values of seasonal forest lianas. We did not find the safety-efficiency trade-off. Merging our results with previously published data revealed a high variability of resistance to embolism in both trees and lianas, independent of forest types. The high hydraulic efficiency of lianas detected here probably favours their rapid growth across tropical forests, but differences in hydraulic safety highlight that some species are highly vulnerable and may rely on other mechanisms to cope with drought. Future research on the lethal dehydration threshold and the connection between hydraulic resistance strategies and liana abundance could offer further insights into tropical forest dynamics under climatic threats.

Evaluating carbon stocks in soils of fragmented Brazilian Atlantic Forests (BAF) based on soil features and different methodologies.

Brazil's Atlantic Forest (BAF) is a highly fragmented, strategic environmental and socio-economic region that represents the fourth biodiversity hotspot while also producing many commodities that are exported globally. Human disturbance plays a pivotal role as a driver of BAF's soil dynamics and behaviors. The soils under Late Primary and Secondary Semideciduous Seasonal Forests (LPSF and LSSF) were characterized by high to moderate resilience, with improved chemical properties as human disturbance decreased. The Transitional Forest to Cerrado (TFC) had the worst soil conditions. Disturbed Primary and Secondary Semideciduous Seasonal Forests (DPSF and DSSF) represent a transitional stage between LPSF/LSSF and TFC. Accordingly, SOCs stocks increased from TFC << DPSF, DSSF < LPSF, LSSF. In BAF soils, to avoid unreliable data, SOCs measurements should be (i) conducted to at least 1m soil depth and (ii) quantified with a CHN analyzer. Human disturbance strongly affected the positive feedback between vegetation succession, SOCs, and soil nutrition. Soil development decreased as human disturbance increased, thus negatively affecting SOCs. Soils in the BAF require a long time to recover after the end of human disturbance, thus suggesting that preservation strategies should be prioritized in remnant BAF fragments.

Seed bank and aboveground vegetation of Atlantic Forest re‐growing on mining tailings in Mariana: Highlighting diversity patterns of functional groups

AbstractNatural regeneration after mining activities depends largely on the soil seed bank (SSB) and aboveground vegetation (AGV) richness and composition. We evaluated the species diversity pattern of the SSB and AGV on soil and technosol across second‐growth Atlantic Forests (SGFs) after mining tailings deposition in Mariana, southeastern Brazil. Two second‐growth Atlantic seasonal semideciduous forests of different stand ages were selected: a 3‐year‐old stand of SGF re‐growing on tailings (SGF tailings) and a 30‐year‐old stand of native reference forest not affected by tailings (SGF nontailings). Overall, the results showed significant differences in forest attributes (species richness and composition) in the SSB and AGV between the two forest patches evaluated (SGF tailings and SGF nontailings). Moreover, both nonzoochoric and zoochoric dispersed species of AGV showed significant differences between second‐growth forests, with higher variability of community‐weighted mean in SGF tailings. The result shows smaller differences in species richness between forest types for both SBB (ranging 85 and 90 species) and AGV (~55 species). Despite the time difference between the secondary forest and the absence of zoochoric species in the tailings seed bank, the AGV that are re‐growing on mining tailings presented a high proportion of zoochoric species. This pattern of species richness and community composition variability observed in the technosol seed bank, and AGV that are re‐growing after the deposition of mining tailings are important recovery indicators for plant communities affected.

Edge effect on floristics and structure in Seasonal Semi-deciduous Forest in the Semi-arid region

Edge effect on floristics and structure in Seasonal Semi-deciduous Forest in the Semi-arid region

The effects of white-popinac on regenerating seasonal semideciduous forests propagate across spatial scales

The effects of white-popinac on regenerating seasonal semideciduous forests propagate across spatial scales

Complexity of the Male Perfume of Eulaema nigrita from Forest and Woody Physiognomies of the Brazilian Savanna: Is There a Relationship with Body Size and Wing Wear?

Male orchid bees collect volatile and semi-volatile compounds from the environment for storage and accumulation in specialized hind legs. Later, these compounds form a perfume blend used during courtship to lure conspecific females for mating. Male orchid bees perfume has been suggested to play an important role as a sexual signaling trait involved in pre-mating isolation of species, functioning as an indicator of male genetic quality. Eulaema nigrita Lepeletier (Apidae: Euglossini) is a common species in both forested and woody savanna (Cerrado stricto sensu) physiognomies of the Brazilian savanna biome. By identifying the chemical composition of male E. nigrita perfume, we tested for differences in the bouquet chemical profile in populations from remnants of seasonal semideciduous forest and woody savanna. In addition, we assessed the relation between perfume complexity and morphological traits associated with size and age of males. Our analysis showed a low effect of physiognomies on differences in the perfume chemical profile of sampled males. Nevertheless, we observed significant differences in the chemical profile of individuals from two seasonal semideciduous forest remnants, which suggests an environmental effect in individual bouquet. Wing wear measurements were positively related to perfume complexity, consistent with the premise that perfumes from older individuals are indicators of survival capacity in male orchid bees.

Defining priority areas for conservation based on multispecies functional connectivity

Habitat fragmentation poses a significant challenge to biodiversity conservation. Well-designed ecological corridors can effectively enhance connectivity between habitat areas, particularly within Protected Areas (PAs), thereby mitigating biodiversity loss. Herein, we proposed a methodological approach for identifying Priority Areas for Conservation (PACs) of biodiversity based on functional connectivity for different species of birds and terrestrial mammals. We applied the proposed methodology in a biodiverse region in Brazil that harbors a mosaic of PAs and remaining areas of natural vegetation under anthropogenic pressure, primarily from mineral extraction activities. We used ecological corridor simulations as input data and a set of geographic information systems tools to delineate the priority areas. In total, we identified 24 priority areas for the conservation of 10 bird and 5 mammal species under different extinction threat levels and preferential habitat types, which varied among seasonal semideciduous forests, savannas, and rupestrian grasslands. The sizes of the priority areas identified ranged from 834.42 to 7954.36 ha. The proposed methodology can be applied to define priority areas for biodiversity conservation at a regional scale for different species or groups of species worldwide.

Floristic inventory of Melastomataceae of the Iguaçu National Park, Paraná, Brazil

Abstract Melastomataceae is one of the richest families in Brazil, with 1,436 species, 158 occurring in the state of Paraná. Many of the species are pioneers and zoochoric, essential for regeneration and floristic composition of the Atlantic Forest, which is the phytogeographic domain covering the Iguaçu National Park (ParNa Iguaçu). We present the floristic inventory of Melastomataceae of ParNa Iguaçu. Three areas in the park were sampled from May 2019 to March 2020, where two are covered with Seasonal Semideciduous Forest (SSF), and the other in a transition between SSF and Mixed Ombrophilous Forest (MOF). Seventeen species of Melastomataceae in four genera were recorded: Miconia (14 spp.), Acisanthera, Chaetogastra, and Pleroma (with only one species each). Seven species occur in the two vegetation types in ParNa Iguaçu, while six occur only in MOF and four only in SSF. Of the 17 species, six are endemic to Brazil, four of which occur only in the south and southeast regions of the country. This study registers nine new records for the ParNa Iguaçu. Furthermore, the Miconia leaeichleri was collected for the first time in the western region of Paraná, which suggests the necessity for more collection efforts in the western region of the state.

Anfíbios e répteis do Refúgio Biológico Bela Vista – hidrelétrica Itaipu, estado do Paraná, sul do Brasil

Abstract Information regarding species occurrence is fundamental to understanding biodiversity distribution. However, the biodiversity from the west of the state of Paraná has been historically less studied, especially amphibians and reptiles. For this reason, we present the first reptile list of species from the west of the state of Paraná and extend the current list of anurans for the municipality of Foz do Iguaçu. The species list was based on a systematic field study conducted at Refúgio Biológico Bela Vista (RBV) a conservation area within the Hydroelectric Power Itaipu Binacional. We integrated the species list with previous species observations available in the literature for the same place where our sampling was conducted. A total of 41 species of amphibians and reptiles are presented. All amphibians species found were recorded in the field; however, from the 22 species of reptiles recorded, three were historical records obtained before this study. Species were all classified as Least Concern and/or had stable populational status according to the IUCN. Sampling sufficiency was achieved for anurans but not for reptiles, probably due to low abundance of several snake species. The most abundant species of anuran was Dendropsophus nanus, from the Hylidae family, whereas Leptodactylus plaumanni and Scinax squalirostris were represented by only one individual each. The lizard Salvator merianae was the most abundant reptile, and seven species were represented by only one individual each. The most successful sampling method for adult anurans was active search in water bodies whereas most of reptile species were observed by accidental encounters and not through a systematic sampling method. We found that herpetofauna composition from RBV was similar to other communities from Paraná state that also occur within the Semideciduous Seasonal Forest. Finally, as additional information to the species list, we offer species identification keys and discuss the importance of Refúgio Biológico Bela Vista to harbor the anuran and reptile diversity of the region.

Orchidaceae in Iguaçu National Park, Paraná, Brazil

Abstract This study presents a synopsis of the Orchidaceae species in Iguaçu National Park (ParNa Iguaçu), one of the largest Atlantic Forest remnants in the state of Paraná. Orchidaceae is represented in the area by 65 species, distributed in 41 genera, the most representative being Gomesa (7 spp.) and Acianthera (6 spp.). Representatives of three subfamilies are present: Vanilloideae (2 spp.), Orchidoideae (12 spp.) and Epidendroideae (51 spp.) which, as expected, presents the greatest richness (78% of the total). Among the species found, five are considered endemic to Brazil, 23 are endemic to the Atlantic Forest (36%) and one is endemic to Paraná. Thirty-one new records were found for the area. The areas of Mixed Ombrophilous Forest (MOF) had 29 exclusive species, the Semideciduous Seasonal Forest (SSF) had 20, while 16 species occur in both phytophysiognomies. A new occurrence was recorded for MOF. Regarding habit, exclusively epiphytic was the most representative (39 spp.), followed by exclusively terricolous (15 spp.), two vines and one mycoheterotrophic species. Among the families already inventoried in ParNa Iguaçu, Orchidaceae is among the richest and the findings of the present study reinforce the importance of floristic studies for cataloging the local flora.

A comprehensive floristic knowledge of a fragment of Semideciduous Seasonal Forest [Parque Estadual da Serra da Concórdia], Rio de Janeiro, Brazil.

The "Serra da Concórdia" is part of the Atlantic Forest phytogeographical domain in the Brazilian state of Rio de Janeiro and it has a predominant phytophysiognomy of Semideciduous Seasonal Forest. This region underwent intense habitat loss and fragmentation during the 19th century, due to coffee plantations and later pastures. With the decline of these activities, the areas were abandoned, triggering secondary succession. In 2002, the "Parque Estadual da Serra da Concórdia" was established in this region to preserve the remaining forest fragments. The updated list of vascular plants recorded in this protected area, published in the "Catálogo de Plantas das Unidades de Conservação do Brasil", is presented here, along with information on richness, endemism, and conservation status. The "Parque Estadual da Serra da Concórdia" houses 231 vascular plant species, of which 90% are angiosperms, 10% ferns and lycophytes, and 27% endemic to the Atlantic Forest. Ten species are threatened with extinction, three are categorized as Endangered, and seven as Vulnerable. Although there have been expeditions in the "Parque Estadual da Serra da Concórdia", they have been limited, resulting in a low number of records and the species richness for a protected area. This is notable considering the 2,130 Brazilian native vascular plant species recorded in the semideciduous seasonal forest of Rio de Janeiro. Our data indicates that floristic inventories of Brazilian protected areas could help highlight gaps in flora knowledge and support the proposal of effective conservation actions.

Effect of slope on the forest structure of the Atlantic Forest domain in southern Brazil.

The mosaic landscape composition of forest fragments located on high slopes, shallow soils hinder ecological interactions and the survival of plant species. This study aimed to show, in an environment with these characteristics, the effect of the environmental gradient relating the soil, slope, and vegetation of a fragment of the Montane Seasonal Semideciduous Forest. The forest structure was sampled in 12 continuous rectangular plots, with 30 X 20m, totaling 0.72ha. Soil samples were taken by drilling every 20m along the hydrographic divisor and opening of three trenches used as soil sampling sites for in situ determination of soil color, horizon, and nutrients. Horizons were classified as O/A/Cr in the altered rock with a marked presence of gravels, and the soil was classified as Litholic Neosol. The area has a steep slope, from 18.05% to 36.99%. Linear regression analysis indicated an opposite pattern for species richness in relation to slope and a positive relationship between slope and the number of standing dead individuals. Species richness was also positively related to the distance from forest edges. The evaluation evidenced the strong influence of slope and human activities in forest remnant as common to several high-altitude remnants, and small conservation actions can guarantee their maintenance.

Pitfall trap efficiency in sampling small vertebrates (Anura, Squamata, and Mammalia) in fragments of the Southeastern Atlantic Forest, Brazil

Pitfall traps are a sampling method broadly used in studies with small terrestrial vertebrates. In this paper, we compared the efficiency of modified pitfall traps in sampling anurans, squamates, and mammals. In two forest fragments of the Seasonal Semi-deciduous Atlantic Forest, we set up 26 arrays of drift fences and pitfall traps, composed of four 30-liter buckets, each set up arranged in a ‘Y’ shape linked by a fence of 4 m in length and 0.5 m in height. We tested for the effect of an internal rim on the border of the buckets by comparing buckets with and without a rim on capture efficiency. In general, we did not observe any effect of the rims in capture efficiency, independently of the bucket position where the rim was present. Still, terminal buckets with rims were less efficient in capturing rodents. We hypothesized that the use of buckets with rims did not increase the capture of small vertebrates due to the animal’s ability to perceive the rim due to substrate instability. However, the pitfall trap efficiently captures small vertebrates, and we do not recommend using the internal rims.

Qualitative survey of the entomofauna in a semideciduous seasonal sorest remnant

The Atlantic Forest has only 8.5% of its forest remnants and in the state of São Paulo, one of its phytophysiognomies, the Semideciduous Seasonal Forest, has registered accelerated and continuous deforestation, remaining for few areas still preserved, in parks, reserves or on private properties. Insects develop several ecological functions within these systems and are considered good indicators of environmental impacts and important members of biological processes. The objective of the present study was to carry out a preliminary qualitative survey of the diversity of entomofauna in a forest remnant, using the scanning method and photographic record, and to analyze the correlation between the number of specimens recorded and some climatological variables. A total of 213 individuals were registered, distributed among 14 orders and 85. Coleoptera was the most represented order with 64 records. Climatological variables, maximum and minimum temperature, rainfall and relative humidity did not influence the number of organisms. The species richness registered in this study constitutes an immeasurable natural resource, and, therefore, the preservation of this area becomes justifiable, not only because it is contained in a State Park, but also because of its genetic heritage.

Thismia violacea (Thismiaceae), a new mycoheterotrophic species from the Brazilian Cerrado

Thismia violacea is described as a new mycoheterotrophic species discovered in an urban fragment semideciduous seasonal forest in the Brazilian Cerrado. Here we provide detailed morphological descriptions, with notes on the habitat, morphology, and a distribution map.

Registro de libélulas (Odonata) predadas por aranhas (Araneae) na Mata Atlântica, no Sul do Brasil

Dragonflies are insects that act as predators and prey, both in freshwater and associated terrestrial ecosystems, which makes the understanding of trophic relationships established by these insects important. In this sense, the present study aimed to report the predation of Odonata by Araneae in areas of seasonal semideciduous forest, phytophysiognomy of the Atlantic Forest at the Iguaçu National Park (PARNA Iguaçu), and in the Bela Vista Biological Refuge (RBBV). The records occurred at random in 2021 from December 13 to 21, and in 2022 from January 4 to April 22. Five individuals of three species and two morphospecies of Odonata preyed upon by three morphospecies of spiders were recorded. Predation of Odonata by spiders seems to be frequent in different ecosystems, but further studies are required to understand the impact of this predation on the size of dragonfly communities in the Brazilian Atlantic Forest biome.