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Human-induced wildfires are increasing in frequency in tropical forests, and their deleterious consequences for biodiversity include decreases in seed rain, which may be affected directly by fire or indirectly by the creation of edges between forest and non-forest environments. Understanding seed rain is key to assess the potential for natural regeneration in plant communities. We assessed the impact of fire and fire-created edges on seed rain species richness, abundance, size, weight, and dispersal syndromes in Atlantic Forest remnants in Bahia, Brazil. We assessed seed rain at monthly intervals for an entire year along seven 300 m-long transects placed perpendicular to the edge. We installed seed traps at the edge and at 20, 40, 60, 80, 100, and 150 m into the burnt area and into the forest from forest edge. We recorded a total of 9,050 seeds belonging to 250 morphospecies. We did not observe edge influence; however, we detected a lower abundance and proportion of animal-dispersed seeds in the burnt than in the unburnt areas. The seed abundance in the burnt areas was lower and seeds were smaller and lighter than those in the unburnt area. Seed rain in the burnt area was not greater near to the forest than far from it. The abundance and richness of seed rain was positively correlated with tree density. Our findings highlight the lack of seed rain in burnt areas and differences in community composition between the burnt and unburnt areas. Collectively, these results indicate negative consequences on natural regeneration, which can lead to permanent secondarization and challenges for early regeneration of burnt areas, which will initially have impoverished forests due to low seed richness.

Anthropogenic land use and cover changes impact biodiversity worldwide. However, ecological groups are differently affected by landscape composition and configuration. Understanding which groups are negatively affected and which thrive in human-modified landscapes is of paramount importance for conservation management, especially for species such as the frugivorous birds, which play an essential role in seed dispersal. We evaluated the relative importance of landscape composition and configuration, explaining taxonomic and functional diversity and their effects on frugivorous birds in the Brazilian Atlantic Forest. We used a robust dataset encompassing 153 forest fragments in the Atlantic Forest hotspot. We classified species as frugivores based on the percentage of fruits in the diet, and used functional traits related to seed dispersal to measure functional diversity. Our results showed that landscape composition was more important than landscape configuration explaining taxonomic and functional diversity of frugivorous birds. In addition, the interaction between landscape composition and configuration explained the loss of functional traits. We demonstrate a disproportional importance of landscape composition explaining taxonomic and functional diversity of frugivorous birds, whereas the traits related to seed dispersal were explained by both compositional and configurational variables. Thus, we highlighted the need to maintain high habitat amount to increase taxonomic and functional diversity of frugivorous birds. However, the interaction of landscape composition and configuration is of paramount importance to sustain functional traits of frugivores in tropical forest landscapes.

Made available in DSpace on 2021-06-25T10:31:29Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-01-01 Tropical forests are being lost and modified at an unprecedented rate, with extant biodiversity increasingly restricted to human-modified landscapes. Resulting changes in landscape structure are shaping diversity patterns, with features such as habitat amount, edge density, and matrix quality determining species persistence. We assessed the importance of landscape composition (forest amount and matrix composition) and configuration (edge density) on diversity patterns of aerial insectivorous bats in Brazilian Atlantic Forest landscapes. We sampled 40 sites in two nearby sub-regions, one contained more forest cover and shade cacao plantations while the other was less forested and dominated by pastures. Based on echolocation calls, we detected 17 sonotypes that could be attributed to at least 13 species belonging to three families. The two sub-regions comprised bat assemblages similar in species richness but different in species composition and activity levels (a surrogate for abundance). Whereas species richness was not influenced by landscape structure at the largest spatial scale of study, activity levels were shaped by changes in landscape composition and configuration, with different responses for forest and open-area foragers. Decreasing activity of forest foragers was the most evident response of bat diversity to landscape structure at different spatial scales. Given the value of this biological group for key ecosystem services such as pest control, our findings highlight the importance of considering regional landscape features for management and prediction of future scenarios of anthropization. Institute of Biology Federal University of Bahia, R. Barão de Jeremoabo 668, Ondina Biology Department Universidade Federal Rural de Pernambuco, R. Manuel de Medeiros 97, Dois Irmãos Applied Conservation Ecology Lab Programa de Pós-Graduação Ecologia e Conservação da Biodiversidade Universidade Estadual de Santa Cruz, Rodovia Ilhéus-Itabuna, km16, Salobrinho Spatial Ecology and -Conservation Lab (LEEC) Ecology Department São Paulo State University UNESP, Avenida 24 A, Bela Vista Spatial Ecology and -Conservation Lab (LEEC) Ecology Department São Paulo State University UNESP, Avenida 24 A, Bela Vista

Habitat loss is widely recognized as the main driver of biodiversity loss around the globe, yet the effects of habitat fragmentation on biodiversity have been extensively debated in recent years. We used a robust dataset of medium and large-sized mammals to test (a) the Habitat Amount Hypothesis, which postulates that species richness can be mainly predicted by the total amount of habitat surrounding the sampling site, and (b) the effects of habitat fragmentation per se, which may be expected to be weak or mainly positive on species richness. We compiled information on the occurrence of mammal species in 166 forest fragments across the Atlantic Forest. For each forest fragment, we extracted information on patch size, percentage of forest cover (a proxy for habitat amount), and edge density and number of fragments (fragmentation metrics). We related these metrics to mammalian richness considering separately for all species, forest-dependent species, disturbance-tolerant species, and different trophic guilds. All richness measures strongly declined with decreasing forest cover, yet were unaffected by patch size, number of patches and edge density. The only exception occurred with herbivore richness, which was affected by number of patches. However, we found fragmentation per se effects only for herbivore richness. Our results show that mammal richness increased with habitat amount at the landscape, whereas habitat fragmentation per se had significant negative impacts on herbivores only. We therefore recommend maintaining highly forested landscapes and restoring severely deforested areas, being essential for ensuring high richness of mammals.

Made available in DSpace on 2021-06-25T11:10:46Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-01-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Recent studies have characterized the influence of agroecosystems on biodiversity. However, a set of components associated with the management of these areas is still neglected in landscape-level studies, especially in areas of recent agricultural intensification. The resources and conditions provided by agroecosystems to different species are highly variable in space and time, and failing to account for this variation may lead to misleading conclusions about the biodiversity status in these environments. In this perspective, we provide a conceptual overview to highlight why and which landscape components still need to be better explored to provide an adequate assessment of the agroecosystem effects on biodiversity. We used a Brazilian heterogeneous intensive-farming landscape as an example to outline the components that we believe are important for understanding biodiversity patterns in such landscapes. An in-depth description of agroecosystems can help us create better landscape-level management strategies and to design more effective green-way policies. Laboratório de Genética & Biodiversidade Instituto de Ciências Biológicas Universidade Federal de Goiás Spatial Ecology Lab Institute of Biology Federal University of Bahia Spatial Ecology and Conservation Lab (LEEC) Department of Biodiversity São Paulo State University UNESP, Avenida 24 A, 1515, Bela Vista Programa de Pós-Graduação em Ecologia e Manejo de Recursos Naturais Universidade Federal do Acre Instituto de Estudos Sociombientais - IESA Universidade Federal de Goiás Instituto Federal de Goiás Spatial Ecology and Conservation Lab (LEEC) Department of Biodiversity São Paulo State University UNESP, Avenida 24 A, 1515, Bela Vista

The future of tropical forest biodiversity will largely depend on human-modified landscapes. We investigated how medium- to large-bodied mammals respond to factors at local (habitat type), intermediate (land use heterogeneity, forest cover and human population density) and large spatial scales (overall forest cover) in agroforestry landscapes. We surveyed mammals using camera traps in traditional cacao agroforests (cabrucas), intensified cacao agroforests, and forest remnants within two large Atlantic Forest landscapes of southern Bahia, Brazil, representing both high and low forest cover. At the local scale, habitat types differed in their potential to harbour mammal species, with forest remnants and cabrucas showing high conservation value, mainly under contexts of high forest cover, whereas intensified cacao agroforests contained less diversified species assemblages in both landscapes. At intermediate scales, species richness increased with increasing forest cover around forest remnants and intensified cacao agroforests, but the opposite was observed in cabrucas. The effects of human population density were ubiquitous but species-dependent. At the largest scale, species richness was higher in the most forested landscape, highlighting the imperative of maintaining forest remnants to retain forest-dwelling mammals in human-dominated landscapes. We claim that mammal conservation strategies require a multi-scale approach and that no single strategy is likely to maximize persistence of all species. Some species can routinely use traditional agroforests, and a large fraction of mammal diversity can be maintained even if high canopy-cover agroforestry dominates the landscape. Nevertheless, forest patches and highly forested landscapes are essential to ensure the persistence of forest-dwelling and game species.

Some species are more affected than others by edge effects resultant from habitat loss and fragmentation, generally due to human activities. As these specific responses depend on biophysical and behavioral traits of organisms, it is expected that the occurrence of species with particular traits will vary between fragment edges and interiors. Edges are also known to often harbor many invasive species. We performed a meta-analysis of the responses of insect species with different life history traits to anthropogenic edges, focusing on the species’ behavioral characteristics and whether they are considered invasive or not. We systematically searched the Web of Science database for papers on this subject published until May 2018. We examined response ratios for 712 comparisons of anthropogenic edge effects on insects. As expected, the responses differed according to the traits evaluated. Soil-foraging and social insects were negatively affected by anthropogenic edges. Conversely, flying and invasive species were favored by edges. Our analyses suggest that edges, by differently affecting different insect groups, have an important role in structuring local insect communities. Finally, the importance of functional traits in studies of edge effects must be highlighted.

Although certain clonal species are often overdominant in disturbed tropical ecosystems, it is often unclear how this success is related to their patterns of clonal growth and how they respond to abiotic heterogeneity. Here we describe ramet growth and survival in an overdominant Neotropical bracken fern (Pteridium arachnoideum) and assess how these patterns resemble congeneric species and are affected by canopy closure in a savanna–riparian forest transition in southeastern Brazil. We measured frond length from early emergence to senescence during two consecutive years in three clonal patches dominated by P. arachnoideum and associated the resulting growth pattern with the local canopy closure. Pteridium arachnoideum exhibited average frond length and growth rate higher than previously reported for this species and for congeneric species. Frond mortality was generally high shortly after emergence from the ground, but was also much higher in one study site due to ant herbivory. Fronds of P. arachnoideum were higher, showed petiole elongation and higher mortality rate under high canopy closure, suggesting shading avoidance, in contrast to the shade tolerance reported for Pteridium aquilinum. Although our findings indicate that this species is unlikely to represent a threat to the biodiversity of undisturbed Brazilian savanna–riparian forest transitions with continuous canopy, they also suggest that introduction of fast growing tree species with dense canopy may accelerate the restoration of more disturbed and degraded sites.

Conversion of natural to anthropogenic environments affects biodiversity, and the understanding of these impacts may be improved by assessing how different functional groups respond to such land conversion. We studied land conversion impacts on ant functional groups, as ants are ecologically important and respond well to various environmental changes. We hypothesized that conversion of natural to anthropogenic environments modifies the composition of functional groups, fostering generalist and opportunistic groups over specialist ones, with more responses of this type in tropical than in temperate regions. We recovered 412 papers from ISI Web of Science, of which we selected 17 studies, published between 1993 and 2018, that addressed our study’s question. We assessed whether each functional group responded positively or negatively to conversion of natural habitat into anthropogenic land uses and used Monte Carlo tests to assess significance. Ants were affected by natural habitat conversion into monoculture and polyculture and by the conversion of savannas and of tropical and subtropical forests. Land conversion affected six of the 13 functional groups assessed here. In the temperate zone, cryptic species, predators, subordinate Camponotini, cold-climate specialists and tropical-climate specialists were impaired, whereas hot-climate specialists were favored. In the tropics, land conversion negatively impacted fungus-growers and predators. In both climatic zones, several functional groups, mainly those with broad ecological niches, did not respond to land conversion. Our results corroborate that land conversion effects vary among ant functional groups and indicate that the ant fauna of temperate ecosystems may be more susceptible than that of tropical regions.

Ants, an ecologically successful and numerically dominant group of animals, play key ecological roles as soil engineers, predators, nutrient recyclers, and regulators of plant growth and reproduction in most terrestrial ecosystems. Further, ants are widely used as bioindicators of the ecological impact of land use. We gathered information of ant species in the Atlantic Forest of South America. The ATLANTIC ANTS data set-which is part of the ATLANTIC SERIES data papers-is a compilation of ant records from collections (18,713 records), unpublished data (29,651 records), and published sources (106,910 records; 1059 references), including papers, theses, dissertations, and book chapters published from 1886 to 2020. In total, the data set contains 153,818 ant records from 7,636 study locations in the Atlantic Forest, representing 10 subfamilies, 99 genera, 1,114 ant species identified with updated taxonomic certainty, and 2,235 morphospecies codes. Our data set reflects the heterogeneity in ant records, which include ants sampled at the beginning of the taxonomic history of myrmecology (the nineteenth and twentieth centuries) and more recent ant surveys designed to address specific questions in ecology and biology. The data set can be used by researchers to develop strategies to deal with different macroecological and regional-wide questions, focusing on assemblages, species occurrences and distribution patterns. Furthermore, the data can be used to assess the consequences of changes in land use in the Atlantic Forest on different ecological processes. No copyright restrictions apply to the use of this data set, but we request that authors cite this data paper when using these data in publications or teaching events.

Made available in DSpace on 2018-12-11T17:30:08Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-12-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) The Edge Influence is one of the most pervasive effects of habitat fragmentation, as many forest remnants in anthropogenic landscapes are within 100�m of edges. Forest remnants may also affect the surrounding anthropogenic matrix, possibly resulting in a matrix–edge–remnant diversity gradient for some species groups. We sampled dung beetles in 15 agricultural landscapes using pitfall traps placed along transects in matrix–edge–remnant gradients. The remnants were a native savanna-like vegetation, the cerrado, and the matrix was composed of three human-dominated environments (sugarcane, eucalyptus, pasture). More species were observed in cerrado remnants than in adjacent land uses. Dung beetles were also more abundant in the cerrado than in the landscape matrix of sugarcane and eucalypt, but not of pasture. Dung beetles were severely affected by anthropogenic land uses, and notwithstanding their high abundance in some land uses such as pasture, the species richness in these areas tended to be smaller than in the cerrado remnants. We also found that the influence of the edge was evident only for abundance, particularly in landscapes with a pasture matrix. However, this land use disrupts the species composition of communities, indicating that communities located in cerrado and pasture have a distinct species composition, and that both communities are affected by edge distance. Thus, anthropogenic land uses may severely affect dung beetles, and this impact can extend to communities located in cerrado remnants as well as to those in matrices, with possible consequences for ecological processes such as decomposition and nutrient cycling. Spatial Ecology and Conservation Lab (LEEC) Ecology Department S�o Paulo State University UNESP, Avenida 24 A Post Graduation Program in Ecology National Institute of Amazon Research – INPA, Av. Andr� Ara�jo Applied Ecology and Conservation Lab Biological Science Department State University of Santa Cruz UESC, Rodovia Ilh�us-Itabuna, km 16 Spatial Ecology and Conservation Lab (LEEC) Ecology Department S�o Paulo State University UNESP, Avenida 24 A FAPESP: 2013/50421-2 CNPq: 312045/2013-1

Habitat loss represents one of the main threats to tropical forests, which have reached extremely high rates of species extinction. Forest loss negatively impacts biodiversity, affecting ecological (e.g., seed dispersal) and genetic (e.g., genetic diversity and structure) processes. Therefore, understanding how deforestation influences genetic resources is strategic for conservation. Our aim was to empirically evaluate the effects of landscape-scale forest reduction on the spatial genetic structure and gene flow of Euterpe edulis Mart (Arecaceae), a palm tree considered a keystone resource for many vertebrate species. This study was carried out in nine forest remnants in the Atlantic Forest, northeastern Brazil, located in landscapes within a gradient of forest cover (19-83%). We collected leaves of 246 adults and 271 seedlings and performed genotyping using microsatellite markers. Our results showed that the palm populations had low spatial genetic structure, indicating that forest reduction did not influence this genetic parameter for neither seedlings nor adults. However, forest loss decreased the gene flow distance, which may negatively affect the genetic diversity of future generations by increasing the risk of local extinction of this keystone palm. For efficient strategies of genetic variability conservation and maintenance of gene flow in E. edulis, we recommend the maintenance of landscapes with intermediary to high levels of forest cover, that is, forest cover above 40%.

Land-use change is considered the greatest threat to biodiversity worldwide. As such, identifying the drivers that shape biological communities is crucial for enhancing conservation strategies in human-modified tropical landscapes. We used a hybrid patch-landscape design and a multi model inference approach to assess the relative impacts of forest loss, increased edge density and increased pasture cover on dung beetle functional groups in the Brazilian Atlantic Forest – a biodiversity hotspot. Our findings provide novel empirical evidence showing that edge density can be a major driver for dung beetles when compared to forest and pasture cover at the landscape scale. However, forest and pasture cover also influenced some dung beetle responses, supporting the idea that biological communities are negatively affected by habitat loss and changes in land cover. We found that dung beetle body size, protibia area and metatibia length were all larger in landscapes with increased edge density, reinforcing the need for further studies exploring which mechanisms could favour the presence of larger dung beetles in fragmented tropical landscapes. Taken together, these results suggest the need of conservation and management strategies focused on the protection of the remaining Atlantic Forest fragments, and the promotion of forest recovery and reduction in the pasture cover and edge density at the landscape-level.

The effect of the adjacent non-forested environment on the forest near the edge, edge influence (EI), is an important impact in fragmented landscapes and is believed to vary with factors such as forest structure and edge contrast. In order to improve our understanding of the factors governing the variability in EI, we studied microclimate and vegetation at cerrado edges surrounded by variable land uses in southeastern Brazil, a system with both forest and savanna fragments. We determined the significance, magnitude and distance of EI on microclimate, vegetation structure and grass biomass which we measured along five transects perpendicular to fourteen edges in forest or savanna next to different land uses. We introduce a quantitative measure of edge contrast that considers land uses at different distances from the same edge (e.g., a firebreak between a forest edge and a plantation) and verified whether edge contrast is correlated with EI in this system. Notwithstanding the large variation in EI among variables and study sites, there were some similarities in the patterns of EI between forest and savanna edges. Edge contrast was successfully quantified by our measure but was only correlated with EI on moisture and grass biomass. Our results point to the high variability in EI within a region. Our quantitative measure of edge contrast may be useful in explaining variability in EI. However, much unexplained variation remains in the highly fragmented cerrado system which is affected by EI in both forest and savanna fragments.