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Ocotea catharinensis occurs mainly in the Brazilian Atlantic Forest and is highly threatened by timber logging, forest fragmentation, and habitat loss. The remnant populations of this species are genetically rich, which may be related to the presence of long-lived trees, and so it is imperative to understand their growth and age. In this study, we analyzed trees of O. catharinensis from dense ombrophylous forest, its dendrochronological potential, the period of cambial activity and dormancy, and the influence of climate on annual growth. The species showed distinct annually-formed tree-rings, with cambial activity during summer and autumn, and cambial dormancy during winter and spring. A tree-ring width chronology was built from 1852–2015. The estimated age of the sampled trees varied from 40 to 164 years. O. catharinensis in our study site does not show a strong age–diameter relationship, hence similar diameters at breast height resulted in differences in ages by as much as 50 years. The resulting tree-ring width chronology is positively correlated with March precipitation, the transition month between rainy and dry seasons. This study brings valuable contributions to the understanding of the growth of O. catharinensis, which is a novelty for this species and important to the maintenance of these long-lived trees in natural forests.

Os núcleos de vegetação são estruturas formadas espontaneamente por pequenos agrupamentos de indivíduos arbustivos e arbóreos, que, ao evoluírem em pastagens perturbadas, podem contribuir na sucessão ecológica. Para compreender a evolução dos processos de restauração florestal passiva em ecossistemas tropicais, depois de paralisada a pecuária extensiva, foram estudados ambientes com baixa oferta de atributos ambientais localizados na vertente norte dos morrotes isolados entre planície de inundação. Após 40 anos de abandono, os núcleos de vegetação colonizaram 20% dos ecossistemas graminoides amostrados, apresentando-se em estágio moderado de perturbação. A composição florística dos estratos superior e regenerante evidenciou que núcleos com duas ou mais espécies florestais pioneiras e com síndrome de dispersão anemocórica, como Moquiniastrum polymorphum, apresentam alta probabilidade de terem seus processos de restauração catalisados no tempo. Núcleos desenvolvidos apresentam riqueza e abundância maiores em seu estrato regenerante, além de espécies zoocóricas e não pioneiras, sugerindo interações positivas entre processos ecológicos, condição que confere sustentabilidade aos avanços da restauração florestal passiva. O aprimoramento destas informações pode contribuir para o desenvolvimento de modelos de restauração induzidos com base nos efeitos da nucleação.

Anthropogenic changes in the biosphere, driven mainly by human cultural habits and technological advances, are altering the direction of evolution on Earth, with ongoing and permanent changes modifying uncountable interactions between organisms, the environment, and humankind itself. While numerous species may go extinct, others will be favored due to strong human influences. The Bio-Evolutionary Anthropocene hypothesizes that directly or indirectly human-driven organisms, including alien species, hybrids, and genetically modified organisms, will have major roles in the evolution of life on Earth, shifting the evolutionary pathways of all organisms through novel biological interactions in all habitats. We anticipate that, in future scenarios, novel organisms will be continuously created, and contemporary native organisms with no obvious economic use will decline—while anthropogenic-favored and novel organisms will spread. The Bio-Evolutionary Anthropocene hypothesis therefore predicts that humankind and novel organisms will interact within a strong evolutionary bias that will lead to unexpected, and probably irreversible, outcomes for the evolution of life on our planet.

Author(s): Vitoria, Angela Pierre; Avila-Lovera, Eleinis; de Oliveira Vieira, Tatiane; Lima do Couto-Santos, Ana Paula; Pereira, Tiago Jose; Funch, Ligia Silveira; Freitas, Leandro; Pedreira de Miranda, Lia d'Afonseca; Pena Rodrigues, Pablo JF; Rezende, Carlos Eduardo; Santiago, Louis S | Abstract: Abstract:Isotopic composition of leaf carbon (δ13C) and nitrogen (δ15N) is determined by biotic and abiotic factors. In order to determine the influence of leaf habit and site on leaf δ13C and δ15N in the understorey of two Atlantic forests in Brazil that differ in annual precipitation (1200 and 1900 mm), we measured these isotopes in the shaded understorey of 38 tropical tree species (20 in the 1200-mm site and 18 in the 1900-mm site). Mean site values for δ15N were significantly lower at the 1200-mm site (−1.4‰) compared with the 1900-mm site (+3.0‰), and δ13C was significantly greater in the 1200-mm site (−30.4‰) than in the 1900-mm site (−31.6‰). Leaf C concentration was greater and leaf N concentration was lower at 1200-mm than at 1900-mm. Leaf δ15N was negatively correlated with δ13C across the two sites. Leaf δ13C and δ15N of evergreen and deciduous species were not significantly different within a site. No significant phylogenetic signal for any traits among the study species was found. Overall, site differences were the main factor distinguishing traits among species, suggesting strong functional convergence to local climate and soils within each site for individuals in the shaded understorey.

Studies have identified the central region of the Brazilian Atlantic Forest as an area of high biodiversity and endemism. Strong anthropogenic pressure has made protected areas in Rio de Janeiro State important sites for biodiversity conservation as they contain many areas of extreme biological importance. We sought to document and qualitatively describe the arboreal species composition of the Tinguá Biological Reserve by examining the collection data of the herbaria at the Instituto de Pesquisas Jardim Botânico do Rio de Janeiro (RB) and the Universidade Federal Rural do Rio de Janeiro (RBR). The survey identified 563 species belonging to 249 genera and 77 families, including 13 new occurrences for Rio de Janeiro State, 34 endemic species for the state, 17 vulnerable species, 15 endangered species, and one critically endangered species. Our results demonstrate the importance of this environmental protection area to the conservation of many plant populations and identified the region as harboring high tree diversity—thus reinforcing its role as an important forest remnant in a fragmented landscape within a threatened biome.

Background: Variation in the distribution and abundance of woody plants as consequence of disturbances such as fire may be explained by lineage age.Aims: We tested whether lowland tropical tree lineages that colonise secondary forests are more late-diverging than clades from old-growth forests, and whether tree phylogenetic beta diversity from old-growth to secondary forests is higher in burned than non-burned secondary forests.Methods: We sampled tree communities in old-growth forests and in secondary forests with distinct disturbance histories (burned and unburned). We calculated mean family age in each plot, and tested for differences among forest types using ANOVA. A phylogenetic fuzzy-weighting procedure was employed to generate a matrix describing the abundance of tree clades per plot, which was then analysed using a principal coordinate analysis.Results: Most clades found in old-growth forests were underrepresented in secondary forests, which have been heavily colonised by a single species from a y...

The ecological resilience of abandoned pastures has important implications for the potential of passive restoration in the Brazilian Atlantic Forest, especially in the face of the ambitious restoration targets for this biodiversity hotspot. In the present study, we aimed to investigate the influence of past land-use on natural regeneration in two secondary forests that established on abandoned pastures with different land use histories (Abandoned + Fire—15 years since the last fire event and Abandoned—36 years ago) in a lowland Brazilian Atlantic Forest. Both secondary forests exhibit low resilience for the three analyzed attributes: vegetation structure, richness, and species composition. Secondary forests affected by fire have the lowest values for species richness, aboveground biomass and leaf area index compared to old-growth forests. Secondary forests were dominated by Moquiniastrum polymorphum—Asteraceae, which was absent from the old-growth forests. Fire resistance, capacity to establish in nutrient-poor soils and efficient seed dispersal in human-modified landscapes are important attributes that may explain the dominance of this species. We demonstrate that even in sites considered appropriate for passive restoration a priori (e.g. located in a protected area, 36 years since abandonment and close to old-growth forests), secondary forests exhibited low aboveground biomass and communities were dominated by few species. Therefore, our results highlight the effects of past land-use on natural regeneration and suggest the necessity to use interventions such as enrichment plantings, nucleation techniques and assisted natural regeneration in order to accelerate forest restoration.

The Atlantic forest has historically been severely deforested, and only fragments currently remain that are subject to a wide variety of anthropogenic impacts, including edge effects that can cause structural and functional degradation. The Tingua Biological Reserve-RJ comprises approximately 26,000 hectares of well-preserved Atlantic Forest, but it is subject to impacts caused by two canopy openings along oil pipelines. Comparisons were made between pipeline edges and forest interiors to evaluate edge effects on the structure and dynamics of those tree communities. Tree densities were higher along forest edges, apparently increasing over time. Tree basal areas, on the other hand, have decreased along edges due to higher mortality rates. Linear canopy opening edges showed higher densities of small trees, while the interior had more very large trees, indicating changes in successional processes and community structural patterns due to edge effects.

Edge effects and linear canopy openings may change ecological patterns and processes on forests. Here we investigate if these openings in a lowland Brazilian Atlantic forest cause edge effects on seedlings. We sampled seedling communities at forest edges near to two linear canopy openings (gas pipeline and power line) and in interiors far from edges. Comparisons between the seedling communities were performed to access edge effects. Density and basal area patterns were compared using, hierarchical two-way ANOVAs and the number of newly germinated seedlings, mortality and resprouts were compared by one-way ANOVAs. The results showed that edge effects of linear canopy openings affect seedling communities leading to low densities on edges that showed less favorable conditions for arrival, establishment and initial survival. The basal area patterns were not affected by edge effects apparently by the resistance of the seedlings that have more than 4 mm diameter. Therefore, linear canopy openings caused edge effects, which determine low seedling densities on edges. However this pattern is not due to increase mortality on these edges, but probably caused by the reduction on germination and establishment.

Question: Does the creation of linear canopy openings in a lowland Atlantic tropical forest cause edge effects on understorey treelets, saplings and shrubs? Location: Uni~ Biological Reserve, Rio de Janeiro state, southeastern Brazil (22°25′30″S, 42°02′30″W). Methods: We sampled shrub, sapling and treelet communities at forest edges adjacent to two linear canopy openings (gas pipeline and power line) and in forest interiors far from any edge. Rarefaction curves were plotted to assess differences in species richness among treatments. Variation partitioning was used to assess main drivers of species composition and abundance. Partial Mantel correlations were calculated to verify edge effects controlling for effect of space on the abundance of Euterpe edulis palm and two ecological groups. For this purpose, species were classified either as disturbance-tolerant or disturbance-sensitive. Results: Edge effects of linear canopy openings affect understorey species composition, but not species richness. Disturbance-tolerant species were more abundant in edges than in forest interiors, while disturbance-sensitive species did not show differences among treatments. However, the late-successional palm Euterpe edulis, which is abundant in forest interiors, was significantly less common at edges. Response to edge effects was stronger among treelets than shrubs and saplings. Conclusions: The creation of infrastructure-related linear canopy openings caused edge effects that significantly affected understorey communities in the studied lowland Atlantic forest remnant. Such effects however were clearly distinct from those found at typical edges of tropical forest fragments.

Plantations of native-tree species are often recommended for ecological restoration, but the understanding of how these techniques catalyze natural ecological processes is limited. We investigated natural regeneration in five plantations of native trees in the Poco das Antas Biological Reserve (PABR) in the state of Rio de Janeiro, Brazil. The plantations were 9–11 years old, and contained 8–14 native-tree species with different compositions and relative density of species. We analyzed floristic composition, structure (density and basal area) of overstory and understory strata, as well as other ecological attributes (dispersal syndromes, fruit or seed size, and the availability of fruit for frugivores). Zoochorous species comprised 77% of the community, with a prevalence of the two smallest size classes of propagules (< 0.6 and 0.6–1.6 cm) in natural regeneration. The density of zoochorous plants in the understory was positively correlated with their density in the overstory, indicating their influence on natural regeneration (r2 = 0.36; p < 0.0002). Fruit availability for frugivores (density and richness of plants fruiting during the year) was also positively correlated with the density of stems in the understory. Therefore, attributes such as dispersal syndrome and fruiting season should be considered in selecting species to be planted. The differences in natural regeneration observed in each of the native-tree plantations indicated that the performance of plantations as a restoration strategy may differ, depending on initial species composition, planting density, and site conditions.

The timing, duration, magnitude and synchronicity of plant life cycles are fundamental aspects of community dynamics and ecosystem functioning, and information on phenodynamics is essential for accurate vegetation classification and modeling. Here, we recorded the vegetative and reproductive phenodynamics of 479 individuals belonging to 182 tree species monthly over two years in a lowland Atlantic Forest in southeastern Brazil, and assessed the relationship between local climatic conditions and the occurrence and intensity of phenophases. We found a constant but low intensity of occurrence of both leaf fall and leaf flush with respect to canopy cover, resulting in an evergreen cover throughout the year. The timing of the reproductive phenophases was irregular between the two years of observation, and their amplitude was low. In addition, flowering and fruiting phenograms of activity, intensity and intensity corrected by the basal area did not overlap. These results suggest that a combination of phenological records and community-structure parameters allows for the obtainment of more accurate estimates of resource availability over time. We found that differences in growing degree-days (GDD), photoperiod and precipitation over time were related to temporal variation in leaf fall, leaf flush and flowering, with a large consistency in responses across tree species in this lowland Atlantic Forest. Moreover, there was only a weak relationship between climatic conditions and the dynamics of fruit formation and ripening, which were more strongly related to flowering phenodynamics, which is suggestive of indirect effects of climatic conditions on fruiting. Finally, the association we found between the number of days with precipitation and leaf fall dynamics agrees with the view that the greater potential for extreme events may impair plant growth in tropical forests. This reinforces the growing concerns regarding the risk of ecological collapse of tropical forests due to fragmentation and global climate change.

The species related to Vriesea paraibica (Bromeliaceae, Tillandsioideae) have controversial taxonomic limits. For several decades, this group has been identified in herbarium collections as V. × morreniana, an artificial hybrid that does not grow in natural habitats. The aim of this study was to assess the morphological variation in the V. paraibica complex through morphometric analyses of natural populations. Two sets of analyses were performed: the first involved six natural populations (G1) and the second was carried out on taxa that emerged from the first analysis, but using material from herbarium collections (G2). Univariate ANOVA was used, as well as discriminant analysis of 16 morphometric variables in G1 and 18 in G2. The results of the analyses of the two groups were similar and led to the selection of diagnostic traits of four species. Lengths of the lower and median floral bracts were significant for the separation of red and yellow floral bracts. Vriesea paraibica and V. interrogatoria have red bracts; these two species are differentiated by the widths of the lower and median portions of the inflorescence and by scape length. These structures are larger in the former and smaller in the latter. Of the species with yellow floral bracts, V. eltoniana is distinguished by longer leaf blades and scapes and V. flava is characterized by its shorter sepal lengths. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 159, 163–181.

The Atlantic rain forest of Brazil is one of the 25 biodiversity hotspots of the world. It is surrounded by distinct marginal plant communities which are floristically related to the rain forest. We performed an in situ ecophysiological study of six shrub and tree species which are abundant in one or more of these marginal ecosystems. They formed three pairs of taxonomically related species, which, however, differed in geographic distribution and/or habitat preference. We aimed to answer the followingquestions: (1) Do habitat g and specialists differ in ecophysiolog ical behaviour? (2) Are there general trends responsive to site characteristics, irrespective of taxonomic affiliation? (3) In which variables between-site intraspecific variation is more often detected? Plants chosen were the Clusiaceae Calophyllum brasiliense Cambess (swamp forest specialist) and Rheedia brasiliensis (Mart.) Planch & Triana (a generalist plant, occurringin swamp forests and dry, sandy coastal veg etation); the Myrsinaceae Myrsine parvifolia A.DC. (widespread in sandy plains) and Myrsine gardneriana A.DC. (widespread in high-altitude habitats); and the Euphorbiaceae Styllingia dichotoma Muell. Arg. (a coastal inselberg specialist) and Croton compressus Lam. (a generalist found in coastal inselbergs and dry forests). We compared measurements of photosynthesis (chlorophyll fluorescence parameters), stable isotope (d 13 C, d 15 N) and metabolic carbon and nitrogen compounds. Generalists and specialists did not always differ in ecophysiological behaviour: for instance, while widespread generalists such as M. parvifolia and C. compressus were ecophysiologically versatile, R. brasiliense appeared to perform below optimum in all sampled habitats. Light and water were abiotic factors which apparently explained most of the variation found. Overall, ecophysiological responses were often more clearly related to individual species rather than to taxonomic affinities in higher hierarchies (family, genus) or habitat. These results are discussed as a further indication of high biodiversity even in habitats marginal to the rain forest hotspot. r 2005 Elsevier GmbH. All rights reserved.

Three legume tree species (Fabaceae) occurring abundantly in a semi-deciduous tropical dry forest of the Atlantic forest complex in southeastern Brazil were subjected to a comparative ecophysiological study at the end of the dry season/beginning of the wet season. The trees chosen were morphologically very similar: Caesalpinia echinata Lam. and Caesalpinia ferrea Mart. ex. Tul., both 10–20 m of height, of the sub-family Caesalpinioideae, and the somewhat smaller, 2–4 m tall, Machaerium obovatum Kuhlm. & Hoehne of the sub-family Faboideae. Despite their similarities with respect to their geographic distribution restricted to Brazilian dry forests, their comparable abundance in the study site and their phylogenetic proximity, the three species display distinctly different ecophysiological behaviour. Compared to the other two species, C. ferrea had the highest photosynthetic capacity (maximum apparent photosynthetic electron transport rate, ETRmax) and higher saturation light-intensity, was less subject to photoinhibition as indicated by potential quantum yield of photosystem II (F v/F m) and had the lowest bulk N content of which soluble non-protein N compounds were only 1.5%. It showed stronger sun plant characteristics. C. echinata had lower photosynthetic capacity, was under chronic photoinhibition and had high bulk N content of which 6.1% were soluble N compounds with high concentrations of proline. In addition to proline, high concentrations of sugars may serve as osmoprotectants. M. obovatum also showed lower photosynthetic capacity and was under chronic photoinhibition. Here, arginine may have a function as osmoprotectant. The ecophysiological differences between the three species are not related to local abundance. However, the observations presented highlight a contrasting behaviour of the otherwise very similar compatriot species.

Some ecophysiological parameters related to plant performance and fitness (carbon and nitrogen isotope composition and total C and N concentrations in situ chlorophyll fluorescence measurements) were determined for over 30 species in four habitats bordering the montane Atlantic rain forest of Brazil, along a gradient of altitude and rainfall: a dry coastal forest, two areas of sandy coastal plain vegetation (restingas), and a high altitude campo. There was a considerable diversity of ecophysiological behaviour within and between the functional groups we created based on plant life-forms. For instance, both crassulacean acid metabolism (CAM) and C3species were found in most life-forms sampled and throughout all habitats. Despite the variation in rainfall regimes, average overall water-use efficiency was similar between sites, particularly for C3species, while no clear pattern regarding nitrogen-use emerged in this respect. Acute and chronic photoinhibition were found in many species across this gradient, even in CAM plants. However, on average, chronic photoinhibition and lower energy dissipation capacity were more characteristic of plants from the restinga habitats. This suggests that, although plants colonizing these habitats have evolved features to deal with water shortage, adaptation to high light levels has not been fully achieved yet. The ecophysiological performance of some individual species in distinct habitats and in distinct microhabitats within habitats is also discussed.

RESUMO Os processos de fragmentação florestal atualmente representamum dosprincipais riscosà biodiversidade global. Nestecontextoé muito importante considerar estas transformações artificiais aos ecossistemas para compreender até mesmo padrões e processos ecológicos naturais. Neste trabalho é feita uma sinopse teórica que inclui o desenvolvimento de alguns conceitos e uma análise crítica destes, mesmo na falta de um arcabouço conceitual unificador sobre fragmentação florestal. São discutidas algumas teorias sobre limites (i.e. bordas) artificiais e naturais tendo como base as transformações ao longo do tempo e fenômenos de retração e expansão de comunidades e ecossistemas. A sucessão ecológica é brevemente discutida com base nas visões conflitantes de Clements e Gleason e mencionamos a importância de rever alguns modelos sucessionais para elucidar determinados aspectos dos efeitos de borda. Sobre estes efeitos é esboçada uma breve perspectiva histórica da evolução de alguns conceitos. Embora exista um conhecimento relativamentevastosobreosefeitosdebordaafirmamosqueaindaémuito difícilprever atrajetóriados processos ecológicos em bordas assim como as transformações nos padrões naturais.

RESUMO Este estudo teve por objetivo descrever a estrutura e composição florística arbórea de dois fragmentos naturais de florestas periodicamente inundadas na Reserva Biológica de Poço das Antas e compará-los a outros tipos florestais da região. Seis parcelas de 30 m x 20 m foram alocadas em cada fragmento. Todas as árvores (DAP ≥ 10 cm) foram amostradas. Os dois fragmentos, denominados ARI e CM, apresentaram estrutura muito similar. Ao todo foram amostradas 628 árvores pertencentes a 31 espécies e 16 famílias, com forte dominância de espécies heliófilas tolerantes à inundação, como Calophyllum brasiliense, Symphonia globulifera (Clusiaceae) e Tabebuia cassinoides (Bignoniaceae). Estas três espécies foram responsáveis por 73% do valor de cobertura em ARI e 67% em CM. Os índices de diversidade de espécies (H' = 1,75 e 1,99, para ARI e CM respectivamente) foram próximos aos de outras florestas inundáveis do sudeste brasileiro. Os fragmentos apresentaram elevada similaridade florística devido à dominância destas espécies heliófilas. Entretanto, a similaridade de espécies foi baixa em relação às florestas bem drenadas adjacentes. Aparentemente, o alagamento do solo é o maior fator regulador da composição florística desta vegetação.

Habitat fragmentation is one of the leading causes of edge genesis and its effects. Functional tree traits such as wood density, height, and diameter are essential variables from which it is possible to infer several ecological processes. This study assessed the variability of the functional traits of trees over two habitats (edge and interior) of a forest remnant. The hypothesis tested were i) the functional traits would have lower values at the edges than the interior, and ii) environmental variables would influence such differences. This study was carried out in the largest Atlantic Forest remnant within Serra da Tiririca State Park, Brazil, by establishing ten plots (50 × 20 m) among different habitats. Within each plot, wood samples were taken from all trees with a diameter of = 10 cm. It was recorded the altitude, distance from the plots to the edge, and fire records as possible explanatory variables (environmental variables). Wood density was obtained using the immersion method. To verify differences in functional traits by habitat, the Wilcoxon test was applied. Additionally, the influence of explanatory variables on functional traits through generalized linear models was evaluated. One hundred eighty-five trees were recorded at the edges and 218 trees at the interior of the remnant. Wood density and tree height were significantly lower in the edges than in the interior. Furthermore, the best models indicated significant relationships between wood density and habitats, as well as diameter and distance to the edge. This study was effective in raising suitable variables to predict edge effects. RESUMO A fragmentação de habitats é uma das principais causas da criação de bordas e seus efeitos. Características funcionais das árvores, como a densidade da madeira, altura e diâmetro, são variáveis essenciais que permitem inferir vários processos ecológicos. Este estudo avaliou a variabilidade das características funcionais das árvores em dois tipos de habitats (borda e interior) de um remanescente florestal. Foram testadas as hipóteses de que i) as características funcionais teriam menores valores nas bordas do que no interior, e que ii) as variáveis ambientais influenciam essas diferenças. Este estudo foi realizado no maior remanescente de Mata Atlântica dentro do Parque Estadual da Serra da Tiririca, Brasil, estabelecendo dez parcelas (50 × 20 m) entre diferentes habitats. Dentro de cada parcela foram retiradas amostras de madeira de todas as árvores com diâmetro = 10 cm. Além disso, foram registradas a altitude, distância das parcelas até a borda e registros de queimadas como possíveis variáveis explicativas (variáveis ambientais). A densidade da madeira foi obtida através do método de imersão. Para verificar diferenças nas características funcionais por tipo de habitat, foi aplicado o teste de Wilcoxon. Adicionalmente, foi avaliada a influência das variáveis explicativas sobre as características funcionais por meio de modelos lineares generalizados. Cento e oitenta e cinco árvores foram registradas nas bordas e 218 árvores no interior do remanescente. A densidade da madeira e a altura das árvores foram significativamente menores nas bordas do que no interior. Além disso, os melhores modelos indicaram relações significativas entre densidade da madeira e o tipo de habitat; assim como, entre o diâmetro e distância até a borda. Este estudo foi eficaz em abordar variáveis adequadas para prever os efeitos de borda no remanescente.