Seasonal Forest Fragment Research Articles

Reptiles and amphibians from the fragments of seasonal Atlantic Forest in northern Paraná, Brazil

Reptiles and amphibians from the fragments of seasonal Atlantic Forest in northern Paraná, Brazil

Atributos das árvores hospedeiras, e não a diversidade da comunidade, conduzem a abundância de epífitas em florestas tropicais sazonais

Abstract Epiphytes are considered indicators of forest ecological integrity, but the factors that explain their abundance are still not well understood. We here evaluated tree colonization by epiphytes in old-growth monospecific reforestation stands of Astronium urundeuva (M.Allemão) Engl. (Anacardiaceae) and Eucalyptus saligna Sm. (Myrtaceae), in comparison to a neighbor seasonal tropical forest fragment under similar environmental conditions. In each forest type, we identified and measured all trees (planted and colonizers) from 5-cm stem diameter in five 200 m² plots and quantified all vascular epiphytes per tree. Tree species were categorized by bark roughness, canopy deciduousness and growth rate. The abundance of epiphytes and the frequency of host trees were higher in the A. urundeuva plantation than in the native forest, with the E. saligna stand in an intermediate position. Also, we found that host traits influenced the abundance of epiphytes in their trunks. Host trees had average stem perimeter and height both higher than non-hosts, which indicates that colonization is more likely to occur in older trees. The average abundance of epiphytes per tree was higher in species with rough bark, but no relationship was found with canopy deciduousness or tree growth rate. We evidenced, therefore, that forest plantations, even if monospecific, can provide habitat for epiphytes. However, at community level, colonization success, either in native or restored forest, depends on the relative abundance of species whose bark type favors epiphytes establishment.

Pyrogenic carbon stocks and its spatial variability in soils from savanna-forest ecotone in amazon

Forest fragments from Amazon are important long-term carbon (C) reservoirs with an essential role in the global C balance. They are often impacted by understory fires, deforestation, selective logging and livestock. Forest fires convert soil organic matter into pyrogenic carbon (PyC), but little is known about its distribution and accumulation along the soil profile. Thus, the objective of this study is to estimate the refractory carbon stocks derived from PyC accumulated in the soil vertical profile of different seasonal forest fragments in the Amazon. Sixty-nine soil cores (1 m deep) were collected in 12 forest fragments of different sizes considering edge and interior gradients. The mean total organic C (TOC) and PyC contents for the edge and interior gradients were 0.84% and 0.009%, respectively. The PyC/TOC ratio ranged from 0.53% to 1.78%, with an average of 1.32% and increasing in depth, being low when compared with other studies, where the contribution of PyC to TOC ranges from 1 to 9%. PyC stocks on the edge (1.04 ± 0.04 Mg ha−1) differed significantly from the interior (1.46 ± 0.03 Mg ha−1). The analyzed forest fragments presented a weighted PyC stock of 1.37 ± 0.65 Mg ha−1. The vertical distribution of PyC declined in depth with 70% of PyC concentrated in the surface soil layers (0–30 cm). These results indicate that the PyC accumulated in the vertical profile of soils in forest fragments in Amazonia are important, and they need to be considered in Brazilian and global reports on carbon stocks and fluxes.

Characterization of entomogenic galls in areas of seasonal deciduous forest in Southwestern Bahia, Brazil

Galls are small structures induced mostly by insects in different plant organs, and have different shapes and colorations. Knowledge on galls is still sparse in the semiarid region of Bahia. Therefore, the goal of this study was to characterize galls in fragments of seasonal deciduous forest. Sampling was performed in the Bahia municipalities of Boa Nova, Jequié, Poções and Vitória da Conquista. In each site, one fragment was chosen, and in each fragment, plots were established to survey galls on vegetation. We sampled 158 gall morphotypes, representing 49 (morpho) species distributed across 15 families of host plants. Myrtaceae and Malphigiaceae had the highest numbers of gall morphotypes. Most galls were collected from leaves, whereas the most common gall morphotypes were globoid and fusiform.

Selective logging that occurred decades ago is still impacting aboveground biomass and tree assemblage structure in Brazilian semi-deciduous seasonal Atlantic forest fragments

The majority of tropical forests in the world have undergone or are still undergoing selective logging. This human disturbance is among the actions that most affect the dynamics of the carbon stocks of tropical forests and also the vegetation structure, richness, and species composition. One of the most widely used approaches to understand forest responses to this disturbance has been to compare them with other undisturbed forests in the given region. Here, we measure the effects of the selective logging history on the aboveground biomass, tree abundance, basal area, and wood density in four Brazilian Atlantic Forest fragments logged once, 35–45 years before the current sampling. We used two unlogged forest fragments as reference ecosystems. We found 40% less aboveground biomass (AGB) and 31% lower basal area in logged than in unlogged forest fragments. Large trees (trees with a diameter greater than 50 cm) were strongly affected by selective logging, showing AGB, basal area, mean wood density and tree abundance values 59%, 52%, and 46%, respectively, lower in logged forest fragments. We found an increase in the abundance of softwood, early-successional species in logged forests, where 45% of the AGB accumulated was due to only two species (Astronium graveolens Jacq and Gallesia integrifolia (Spreng.) Harms). The opposite was observed in unlogged forest fragments, where two late successional hardwood species (Aspidosperma polyneuron Müll.Arg and Holocalyx balansae Micheli) accumulated 38% of the AGB. Our findings indicate that even decades after the last logging event semi-deciduous seasonal Atlantic Forest fragments with a selective logging history may present different AGB, structure, and functional composition from the expected pattern for old-growth forests in the given region.

The flower structure of Solanum caavurana Vell. (Solanaceae) and aspects of the pollination biology

Aspects of the pollination biology and floral characteristics of Solanum caavurana Vell. Were investigated in a semidecidual seasonal forest fragment in Paraná, Brazil. Anthesis was diurnal and the Pseudaugochlora bees have visited the flowers with more frequency than other species. Sepals and petals had homogeneous parenchymatous mesophyll. The young anther wall was composed of epidermis, two or three layers of endothecium, two middle layers and secretory tapetum. Anthers were poricidal and there was no functional longitudinal stomium. Ovary structure was simple and there was compitum with septum split. Ovules were hemicampylotropous, unitegmic and tenuinucellate with hypostase. The flower of S. caavurana followed the Solanum pattern described in the literature, and the pollination should be made by bees.

Soldier flies (Diptera: Stratiomyidae) on semideciduous seasonal forest fragments, with a list of species for São Paulo State, Brazil, and two new records of species for the country

Soldier flies (Diptera: Stratiomyidae) on semideciduous seasonal forest fragments, with a list of species for São Paulo State, Brazil, and two new records of species for the country

MODELAGEM DA DISTRIBUIÇÃO DIAMÉTRICA DE ESPÉCIES ARBÓREAS EM FRAGMENTO DE FLORESTAS ESTACIONAL SEMIDECIDUAL

ABSTRACT Modeling diameter distribution in natural forests is an important tool for understanding the native woody species dynamics, supporting decision-making for degraded lands management and restoration. Therefore, this work aimed to fit probabilistic density functions to evaluate the diameter structure of three tree species with economic interest, such as Campomansesia xanthocarpa Marl. Ex. O. Berg, Piptadenia gonoacantha (Mart.) J.F. Macbr. and Zeyheria tuberculosa (Vell.) Bureau ex Verl., in a Semideciduous Seasonal Forest fragment at São Paulo State, Brazil. The data came from 83 temporary plots of 10 m x 20 m systematically distributed along 164 ha. Log-normal, Gamma, and Weibull functions were fitted to the three species using the fitdistrplus-package in the R program. Kolmogorov-Smirnov's adherence test was used to evaluate the fits at a 5% probability level. The functions were selected employing Akaike's Information Criterion (AIC) and Schwarz's Bayesian Information Criterion (BIC), in addition to a graphical analysis of the fitted functions. The results indicated that the three species diameter structure is positively asymmetric, representing the exponential pattern, representing continuous natural regeneration. AIC and BIC statistics indicated the Log-normal function to describe the diameter distribution of C. xanthocarpa and Z. tuberculosa, while the Gamma function was the most appropriate for P. gonoacantha. For the three species, the graphical analysis showed the Gamma function results in the best fit without tendency for estimating frequency density per diameter class.

Reproduction of Artibeus lituratus and Sturnira lilium (Chiroptera: Phyllostomidae) in a Semideciduous Seasonal Forest fragment in southern Brazil

Here we evaluate the reproduction and changes in abundance among different reproductive stages for Artibeus lituratus (Olfers, 1818) and Sturnira lilium (E. Geoffroy, 1810) in a Semideciduous Seasonal Forest fragment at southern Brazil. Bats were identified according with sex and reproductive stages based on secondary characters, as follows: young bats (1); males with descending testes (2); males with abdominal testes (3); non-pregnant females (4); lactating females (5); pregnant females (6); pregnant-lactating females (7); post-lactation females (8). Abundance was explored monthly in each reproductive stage considering rainy (October to March) and dry (April to September) season. Bat abundance changed over the months and between species, with August and June with highest abundance for A. lituratus and February, June and September for S. lilium. Both species showed a pattern of bimodal polyestry, with first pregnancy occurring at the end of dry season and second in the middle of rainy season. The data here presented contribute to understand reproductive biology and abundance changes over one year for A. lituratus and S. lilium in a Semideciduous Seasonal Forest fragment, reducing knowledge gap about reproduction patterns of these species.

Bonobo social organization at the seasonal forest-savanna ecotone of the Lomami national park.

Examining the relationship between food and primate social organization helps us understand how the environment shaped hominin social evolution. However, there is debate as to whether the social differences between our two closest relatives, bonobos (Pan paniscus) and chimpanzees (Pan troglodytes), are due to differences in food availability between their respective habitats or to nonenvironmental factors. The most prominent theory is that bonobo communities have more socially cohesive, stable parties, centered on gregarious females because they evolved in food-rich habitat where individuals, especially females, are less burdened by competition with groupmates. However, more research on bonobos in habitats with seasonal variation in food is needed. This study measured food availability and bonobo social organization at Luzaka, a new site in a seasonal forest fragment. Fruit abundance and dispersion were recorded for a year at Luzaka with the same methods used at Wamba, a bonobo site in more seasonally stable habitat and terrestrial herbaceous vegetationdensity was measured. At Luzaka, bonobo parties were also recorded for a year using camera traps. Fruit was more seasonal and dispersed at Luzaka than at Wamba. However, the social organization of Luzaka bonobos resembled social organization of bonobos at less seasonal sites. There were minor effects of fruit clumping on party size without effects on the proportion of females in parties suggesting that at Luzaka, the clumping of fruit slightly affected social cohesiveness but does not disproportionately affect females. Bonobo social cohesiveness and female gregariousness appears consistent and compatible with seasonal habitat.

Flower structure of Serjania fuscifolia (Sapindaceae) and its relationship with visiting insect

Serjania fuscifolia is a species that occurs often in edges of forest fragments, it flowers in the autumn-winter period and is visited by insects. This species constitutes an interesting model of floral biology, especially for its potential to provide food resources to the entomofauna. Its floral structure was investigated, and its relationship with visiting insects was also verified. Five specimens of this species were analyzed in a seasonal semideciduous forest fragment surrounded by agricultural fields in the years 2019 and 2020. Flowers were embedded in historesin and sectioned in a microtome; collections and observations of insects followed a floral biology protocol. Four individuals showed monoecy, with temporal variations in floral types, and only one individual was male unisexual. Both types of flowers showed non-glandular and glandular trichomes, lipid-secreting cells and nectar in abundance. Pollen grains were exposed only on male flowers, while indehiscent anthers on female flowers showed pollen with 35% viability. Flowers consist of perianth with homogeneous mesophyll, anther wall with five cell-layers, style with a trilobed strand of transmitting tissue, and ovary wall with adaxial meristem. The plant was visited by 50 species of insects, with emphasis on Hymenoptera (21 sp.), Lepidoptera (15 sp.) and Diptera (10 sp.)

The avifauna of a semideciduous seasonal forest fragment in the countryside of Barra Mansa, Rio de Janeiro, Brazil

The Atlantic Forest is one of the richest and most threatened biomes in the world, a fact that configures it as a global hotspot. We provide here a list of bird species recorded in the municipality of Barra Mansa (RJ), during ten years of ad libitum observations in a fragment of Semideciduous Seasonal Forest, one of the most devastated phytophysiognomies of this biome. We recorded 192 species, of which 107 present some degree of forest dependency, 22 that present migratory activity, 24 that are endemic in the biome or in Brazil and 5 that are relevant to conservation as they are almost threatened or vulnerable at some level (global, national or state). Regarding the trophic guild, there was a predominance of insectivorous (n=67) and omnivorous (n=58) species, which denotes some environmental quality, but pressured by an imminent anthropization. Given the obtained results, the importance of the analyzed fragment for the maintenance of the local biodiversity becomes evident.

Time budget and foraging strategies of two provisioned groups of tufted capuchin monkeys, Sapajus libidinosus, in a small, seasonal urban forest fragment.

Studies of urban monkeys provide important insights into the behavioral flexibility of primate species. We studied two provisioned groups of capuchin monkeys that inhabit a small forest fragment in the city of Goiânia, Brazil. One of the groups was dominant and had priority of access to both native and provisioned resources. Anthropic resources were available in two relatively small areas within this forest, but varied in their quality. We hypothesized that intergroup dominance and the seasonality of native resources would have different impacts on the foraging strategies and use of space by the two study groups. Data on the location of the members of the two groups, their behavior, and consumption of different food items were collected during five dry season and five rainy season months. The members of the dominant group spent more time in the provisioned area where anthropic food was less costly to obtain and consumed more provisioned fruit and vegetables than the members of the subordinate group. The differences between groups were exacerbated during the dry season, when sources of native fruit were less abundant. The results of the present study illustrate how capuchins may respond to the variation in proximate factors, such as intergroup dominance and seasonality. These factors were determinants to the variation in the diet and the use of space observed between the two study groups.

Leaf litterfall, decomposition and nutrients release in a Seasonal Semideciduous Forest in Southern Brazil

Biogeochemical cycling study of ecosystems and their functioning are fundamental for planning conservation practices and management of forest remnants in Brazil. The objective of the study was to characterize the leaf litterfall production rate and the nutrients release via decomposition in a fragment of Seasonal Semideciduous Forest, in Southern Brazil, in advanced stage of regeneration. For two years, evaluations of litterfall and leaf litter decomposition (using the mass loss method with litterbags) were performed monthly, as well as their nutrient content analysis. Annual input of leaf litterfall was 4,532.7 kg ha-1 of dry matter, which promoted, for the two-year period, a supply of 195.5, 9.2 and 55.3 kg ha-1 of N, P and K, respectively. The litter nutrients use efficiency followed the decreasing order P > K > N. The annual decomposition constant for leaf litter was 1.16, reaching a half-life at 215 days, making 84.4% N, 72.7% P and 92.9% K available at the decomposition end of two years. In the two years of collection, the largest deposition rate of litter occurred in the spring, with the highest peak in October, indicating a seasonal deposition behavior. The forest fragment presents high production of leaf litter (66% leaves) and input of N. The rapid decomposition of leaf litter contributes to the release of nutrients over time, N and K initially, and P in the long run. P is limited due to the high efficiency of its use.

Aboveground biomass accumulation and tree size distribution in seasonal Atlantic Forest restoration sites

Tropical forests undergoing restoration can present high biomass accumulation rates, especially in the first 20 years. However, native species reforestations often present a bias toward fast growth, low wood density, and small maximum adult size species, contrasting with most mature forest species. Since tree species adult size and wood density are key traits that influence biomass accumulation, these induce uncertainty regarding carbon uptake capabilities of restoration projects in the long term. We compared the density of individuals (DI), basal area (BA), aboveground biomass (AGB), and weighted average wood density (WDW) in 13–14‐year‐old restoration sites and in mature seasonal Atlantic Forest fragments. We also assessed the contribution of pioneer and non‐pioneer and planted and non‐planted species on these variables at restoration sites. Furthermore, we investigated the DI and WDW for saplings and seedlings, in order to foresee changes in forest structure that may result from natural recruitment of dense‐wood mature species. The BA and WDW at restoration sites were similar to forest fragments, except for large trees (DBH ≥50 cm). Restoration sites recovered AGB to the level of forest fragments only for the smaller size class (DBH 5–19.9 cm). Planted pioneer and non‐pioneer species accumulated the greatest AGB (93%), BA (94%), and DI (90%) at restoration sites. The DI of non‐planted non‐pioneer species with higher WDW increased among saplings and seedlings at restoration sites. The presence of species with a larger adult size and higher WD may indicate long‐term increase in biomass accumulation at restoration sites.

High richness of non-volant mammals in a seasonal forest fragment in southeastern Brazil

The seasonal forest formations of the Atlantic Forest are a threatened and poorly known habitat. We present here a list of the non-volant mammals occurring in a 515‑ha forest fragment known as Santa Maria and located in the Brazilian state of São Paulo. Our surveys are based on live trap captures, camera traps, and active searches for footprints, as well as secondary data. We list 29 species of non-volant mammals in the fragment, recorded between 1996 and 2021. One species found in the fragment, Leontopithecus chrysopygus, is globally endangered. Two species are classified as "vulnerable" in the global red list: Myrmecophaga tridactyla, and Tapirus terresris. One species, Panthera onca, is classified as "critically endangered" in São Paulo state. The red howler, Alouatta guariba, was not recorded after 1999 and has probably been extirpated in the fragment. We show that the number of non-volant mammal species in Santa Maria fragment is high, in relation to its size. The fragment is also in a strategic position, between the Morro do Diabo state park and the Black Lion Tamarin Ecological station, the two largest protected areas in the region. Considering its high mammal richness and its possible role as stepping stone for the local fauna, we recommend that the fragment become a protected area.

New records and a significant range extension of the recently described Pelexia vinosa A.W.C. Ferreira, M.I.S. Lima & Pansarin (Orchidaceae) in southernmost Brazil

We present new records for Pelexia vinosa A.W.C. Ferreira, M.I.S. Lima & Pansarin, a Brazilian terricolous orchid described in 2012 and at that moment known only from the type population and considered endemic to the state of São Paulo. We report the occurrence of populations in seasonal semideciduous forest fragments at three locations in the southernmost Rio Grande do Sul state, Brazil. This would mean that the species distribution is extended by ca. 1,500 km in a straight line from previous records. We also reassess the conservation status of P. vinosa as Endangered.

Selective Logging that Occurred Decades Ago is Still Impacting Aboveground Biomass and Tree Assemblage Structure in Brazilian Semi-Deciduous Seasonal Atlantic Forest Fragments

Selective Logging that Occurred Decades Ago is Still Impacting Aboveground Biomass and Tree Assemblage Structure in Brazilian Semi-Deciduous Seasonal Atlantic Forest Fragments

Population structure of understory, canopy/emergent tree species in Brazilian Atlantic Forest remnants with different Conservation status

The size and spatial structures of populations are a synthesis of demographic attributes and indicators of competitive ability, colonization, and survival. In this study, the objective was to analyze the height and spatial pattern of an understory and canopy/emergent tree populations group in two protected fragments of seasonal semideciduous forest, one with a history of selective logging and another without selective logging evidences. Six species with high importance values (IV) from different guilds were selected and height and spatial pattern analysis was realized in both areas. Then, comparison of results was realized in an area with history of selective logging and another without selective logging evidences. Differences in height and spatial pattern were found between the two areas, including species not directly exploited. In Logged Forest the size structure for all species presented a higher coefficient of skewness, showing a greater proportion of young trees. Random distribution was observed for the majority of species in both areas. Some emergent/canopy species had a deficit of individuals in the largest size classes and the majority of understory species showed more individuals in Logged Forest. Selective Logging changed the pattern of populations. Selecting species based on IV together with spatial patterns data contribute to demonstrating the impacts of exploitation. The Logged Forest is surrounded by an agricultural matrix, limiting arrival and dispersion of propagules of shade-tolerant species. Efforts to connect surroundings fragments to Logged Forest will be necessary.

DIVERSITY OF NOCTURNAL BIRDS IN FOREST FRAGMENTS IN THE PAMPA BIOME, SOUTHERN BRAZIL

Studies on nocturnal birds in the Neotropical region are still considered scarce in the literature, lacking bioecological approaches to this group in the wild. The present study aimed to obtain information on the abundance, richness, and composition of nocturnal birds found in forest fragments in the Central Region, the state of Rio Grande do Sul, Brazil. Data collection was conducted between 2015 and 2016 through listening points, in three fragments in the region (defined as A, B, and C). Seven species of nocturnal birds were recorded and the most abundant were Ferruginous Pygmy-Owl (Glaucidium brasilianum) and Tropical Screech-Owl (Megascops choliba). Summer was the most representative season in abundance and species richness. In terms of composition, fragment (A) presented a distinction, with an exclusive species, the bacurau-chintã (Hydropsalis parvula). The feeding guilds are composed of carnivorous and insectivorous individuals, most of which are annual residents of the state. The assemblage of nocturnal birds recorded in the fragments of deciduous seasonal forest in the central region reports information about this group, which seems to be locally adapted to live in these altered forest environments, which in a way, still provide resources to meet their trophic needs.