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It is now clear that dry forest regeneration relies on a set of regeneration mechanisms such as seed rain, seed and seedling banks, and resprouts that operate simultaneously, but their relative contribution and drivers remain poorly understood. In this paper, we examined the role of seed rain, seed soil bank, seedling, sapling, and resprout assemblages in the regeneration of a Caatinga dry forest in northeast Brazil. We also examined how these regeneration mechanisms respond to chronic disturbances, rainfall, soil fertility, and light in 18 plots located in old-growth forest stands. A total of 5239 seeds from seed rain, 932 seeds in the soil seed bank, 158 seedlings, 85 saplings and 416 resprouts were recorded. Overall regeneration mechanisms provided low-density and impoverished assemblages when examined isolated. Soil seed bank and seed rain provided up to 423 and 35.5 seeds per m2, respectively. Seedling and sapling assemblages were dominated by a small set of species (mostly Jatropha mutabilis, Pityrocapa moliliformis, and Trischidium molle), which were both frequent and accounted for most of the individuals. Resprouting was the most important mechanism, accounting for 63.1% of all individuals in the seedling, sapling, and resprout assemblages. Chronic disturbances were identified as key drivers, negatively affecting several community-level attributes of seed rain, soil seed bank, seedlings, and resprouts. Soil fertility and leaf area index (i.e., light availability) were negatively related to seedling and sapling abundances, respectively. Furthermore, the effect of environmental factors on regeneration was more pronounced in disturbed areas. Species composition of saplings and resprouts were associated with chronic disturbances and environmental factors. Our results suggest that, in human-modified landscapes, Caatinga forest regeneration relies primarily on resprouting, while other mechanisms play a minor role in plant species recruitment and maintenance along gradients of disturbances and environmental factors. Given the predicted increase in aridity associated with increased human disturbance, the Caatinga dry forest may experience shifts in forest structure and regeneration patterns. We refer to an absolute prevalence of vegetative propagation leading to a low-statured forest dominated by multi-stem individuals, with unknown effects on long-term forest dynamics and resilience, including community-level homogenization.

Abstract Despite evidence about the contribution of Indigenous Peoples and local communities (IPLCs) to conservation, prevailing strategies still seek their separation from nature, often triggering conflicts. Current pledges to expand global protected area coverage suggest a need for the critical analysis of governance quality and the way conservation interacts with the well‐being of IPLCs. We present the case of Catimbau National Park in the Caatinga dry forest of northeast Brazil, where we explored connections between the well‐being of IPLCs and landscape through different values, practices and institutions, and perceptions of how environmentally just the park's governance has been. The well‐being of IPLCs is inextricably connected with the Caatinga landscape, through multiple place‐based relational values that, although differing between Indigenous and non‐indigenous inhabitants, have in both cases developed over generations. Although often framed as degraders, IPLCs exhibit a strong motivation to conserve, reflected through local institutions including forest gardens, sustainable use regulations, restoration activities and prevention of external encroachment. The strict form of protected area implemented at Catimbau, instead of a locally led or sustainable use reserve, explicitly targeted the resettlement of IPLCs and livelihood reorientation. These imposed objectives have clashed with a way of life in this peopled landscape and precluded local stewardship on a larger scale. Long‐term conflict arose through governance deficiencies which sparked multidimensional injustices. These include not only the misrecognition of local values and customary institutions but also the lack of procedures for consent or decision‐making influence, plus distributional harms including tenure insecurity and denied development assistance. Development and conservation strategies must reject narratives about poor, resource‐dependent rural communities and embrace the opportunities that local knowledge and institutions bring for effective conservation. As conservation efforts are expanded post‐2020, the people of the Caatinga and beyond must be recognised as embedded and a key part of any solution. In strict protected areas like Catimbau, where social conflict constrains their ability to function, seeking legal changes in governance type can be onerous. However, we describe other local‐level actions to build relationships and agency that may foster transitions towards better governance, and just treatment of IPLCs. A free Plain Language Summary can be found within the Supporting Information of this article.

Abstract Drastic changes in vegetation structure caused by exceeding ecological thresholds have fueled the interest in tropical forest responses to climate and land-use changes. Here, we examine the potential successional trajectories experienced by the largest dry tropical forest region in South America, driven by climate conditions and human disturbance. We built potential distribution models for vertebrate taxa associated with forest or shrub habitats to estimate natural vegetation cover. Distribution patterns were compared to current vegetation across the entire region to identify distinct forest degradation levels. Our results indicate the region has climatic and soil conditions suitable for more forest cover than is currently found, even in some areas with limited precipitation. However, 11.04% of natural cover persists across such an immense region, with only 4.34% consisting of forest cover. Forest degradation is characterized by the dramatic expansion of shrubland (390%), farming, and non-vegetation cover due to changes in land-use, rather than climatic conditions. Although different climate conditions have been the principal drivers for natural forest distribution in the region, the forest seems unable to resist the consequences of land-use changes, particularly in lower precipitation areas. Therefore, land-use change has exceeded the ecological thresholds for the persistence of forests, while climate change may exacerbate vegetation-type transitions.

Wildfires associated with land-use and climate change have considered a key driver to the Amazon forest collapse. However, achieving a detailed understanding of how human-related disturbances impact forest successional trajectories needs comprehensive information spanning forest strata. Here, we investigate the impact of recurrent wildfires on forest structure, species diversity, and composition, making a comprehensive assessment of the regenerating, understory, and canopy tree communities in a sustainable use reserve in the eastern Amazon. Plant communities were described across 16 forest stands (old-growth, burned once and twice) sampling a total of 3620 individuals and 326 tree and palm species. Wildfires affected all attributes of forest structure. Aboveground biomass decreased by 44% in forest burned once, and 71% in twice-burned forest stands. Forest canopy was the most affected strata after the second fire, with a 44%-decrease compared to unburned forest. The same pattern emerged for basal area, which decreased by an average of 27.5% after the first fire and 53.8% following the second fire event. Overall, plant communities experienced a 50%-loss of species richness after two fires, including both dominant and rare species. Plant communities also became more dissimilar as fire events accumulated, with 58%–61% increase in species dissimilarity following two fires events. As wildfires reoccured, the old-growth forests of our focal landscape were converted into a mosaic of regenerating forest stands dominated by local short-lived pioneers (i.e. low-biomass early-regenerating forest stands) and a few tree species less sensitive to fire. Our findings highlight the urgent need to secure a resilient future for Amazonian forests with actions needed to support local livelihoods whilst reducing the prevalence of ignitions sources and allowing forest recovery.

Under continuous human disturbance, regeneration is the basis for biodiversity persistence and ecosystem service provision. In tropical dry forests, edaphic ecosystem engineering by biological soil crusts (biocrusts) could impact regeneration by influencing erosion control and soil water and nutrient fluxes, which impact landscape hydrology, geomorphology, and ecosystem functioning. This study investigated the effect of cyanobacteria-dominated biocrusts on water infiltration and aggregate stability in a human-modified landscape of the Caatinga dry forest (NE Brazil), a system characterized by high levels of forest degradation and increasing aridity. By trapping dust and swelling of cyanobacterial filaments, biocrusts can seal soil surfaces and slow down infiltration, which potentially induces erosion. To quantify hydraulic properties and erosion control, we used minidisc-infiltrometry, raindrop-simulation, and wet sieving at two sites with contrasting disturbance levels: an active cashew plantation and an abandoned field experiencing forest regeneration, both characterized by sandy soils. Under disturbance, biocrusts had a stronger negative impact on infiltration (reduction by 42% vs. 37% during regeneration), although biocrusts under regenerating conditions had the lowest absolute sorptivity (0.042 ± 0.02 cm s−1/2) and unsaturated hydraulic conductivity (0.0015 ± 0.0008 cm s−1), with a doubled water repellency. Biocrusts provided high soil aggregate stability although stability increased considerably with progression of biocrust succession (raindrop simulation disturbed: 0.19 ± 0.22 J vs. regenerating: 0.54 ± 0.22 J). The formation of stable aggregates by early successional biocrusts on sandy soils suggests protection of dry forest soils even on the worst land use/soil degradation scenario with a high soil erosion risk. Our results confirm that biocrusts covering bare interspaces between vascular plants in human-modified landscapes play an important role in surface water availability and erosion control. Biocrusts have the potential to reduce land degradation, but their associated ecosystem services like erosion protection, can be impaired by disturbance. Considering an average biocrust coverage of 8.1% of the Caatinga landscapes, further research should aim to quantify the contribution of biocrusts to forest recovery to fully understand the role they play in the functioning of this poorly explored ecosystem.

Although the herbaceous plants concentrate the diversity of vascular plants in the largest dry forest of South America, the Brazilian Caatinga, their responses to environmental modifications are poorly known. We assessed the taxonomic, phylogenetic and functional responses of herb communities to independent gradients of annual rainfall (510−940 mm), chronic disturbance (0–100%), and local density of woody plants in 19 forest sites of the Catimbau National Park, Northeast Brazil. We expected that drier and more chronically disturbed stands with greater density of woody plants would support less-dense and impoverished herb communities. We recorded 6787 individuals belonging to 57 species and 53 genera, predominantly dicots. Rainfall reduction decreased herb density, benefited a small set of particular genera, increased phylogenetic clustering within terminal clades and favored species pollinated by birds and butterflies. Increased chronic disturbance did not affect herb density and richness, but benefited another set of herb genera, reduced phylogenetic clustering and favored dicot herbs pollinated by bees. The density of woody plants also affected different aspects of taxonomic, phylogenetic and functional dimensions. By shaping different components of herb diversity, rainfall reduction and increased chronic disturbance are likely to act synergistically and drive the Caatinga towards multiple successional pathways.

Global sustainability rests on a myriad of benefits provided by natural ecosystems that support human livelihoods and well-being, from biodiversity persistence to climate regulation. The undeniable importance of conserving tropical forests has drawn most of the conservation spotlight towards it. However, open ecosystems such as the Brazilian Campo Rupestre (rupestrian grassland), have been historically overlooked despite their high diversity and key associated ecosystem services. We highlight major current threats to the persistence of the Campo Rupestre emphasizing its ecological, social, cultural, geo-environmental, and economic importance. We call attention to the importance of the Campo Rupestre as a reservoir of biodiversity and ecosystem services and offer priority actions that resulted from discussions involving scientists, industry representatives, environmental managers, and other members of civil society. Proposed actions include efforts related to ecological restoration, sustainable ecotourism, protection of traditional ecological knowledge, identification of emerging research questions, and development of tailored public policies. Such issues are integrated into a framework that collectively represents a road map to safeguard the Campo Rupestre from further degradation and steer its historical overexploitation towards sustainable management. Safeguarding the future of non-forest biomes like this poses a challenge to current paradigms of nature conservation. By establishing priorities and guidelines, we propose an actionable plan, which we hope can support informed decision-making policy towards a sustainable use of the Campo Rupestre.

Background Biological invasion is one of the main threats to tropical biodiversity and ecosystem functioning. Prosopis juliflora (Sw) DC. (Fabales: Fabaceae: Caesalpinioideae) was introduced in the Caatinga dry forest of Northeast Brazil at early 1940s and successfully spread across the region. As other invasive species, it may benefit from the soils and seed dispersal by livestock. Here we examine how seed dispersal ecology and soil conditions collectively affect seed germination, early seedling performance and consequently the P. juliflora invasive potential. Methods Seed germination, early seedling survival, life expectancy and soil attributes were examined in 10 plots located across three habitats (flooding plain, alluvial terrace and plateau) into a human-modified landscape of the Caatinga dry forest (a total of 12,000 seeds). Seeds were exposed to four seed dispersal methods: deposition on the soil surface, burial in the soil, passed through cattle (Boss taurus) digestive tracts and mixed with cattle manure and passed through mule (Equus africanus asinus × Equus ferus caballus) digestive tracts and mixed with mule manure. Seeds and seedlings were monitored through a year and their performance examined with expectancy tables. Results Soils differed among habitats, particularly its nutrient availability, texture and water with finely-textured and more fertile soils in the flooding plain. Total seed germination was relatively low (14.5%), with the highest score among seeds buried in the flooding plain (47.4 ± 25.3%). Seed dispersal by cattle and mule also positively impacted seed germination. Early seedling survival rate of P. juliflora was dramatically reduced with few seedlings still alive elapsed a year. Survival rate was highest in the first 30 days and declined between 30 and 60 days with stabilization at 70 days after germination in all seed treatments and habitats. However, survival and life expectancy were higher in the flooding plain at 75 days and lower in the plateau. Prosopis juliflora seedling survival and life expectancy were higher in the case seeds were mixed with cattle manure. Synthesis Prosopis juliflora seeds and seedlings are sensitive to water stress and habitat desiccation. Therefore, they benefit from the humid soils often present across human-disturbed flooding plains. This plant also benefits from seed deposition/dispersal by livestock in these landscapes, since cattle manure represents a nutrient-rich and humid substrate for both seeds and seedlings. The quality of the seed dispersal service varies among livestock species, but this key mutualism between exotic species is due to the arillate, hard-coated and palatable seeds. Prosopis juliflora traits allow this species to take multiple benefits from human presence and thus operating as a human commensal.

Distinct approaches have been adopted for tropical forest restoration in the last decades. The long-term viability of these restored forests and their capacity to provide the required services demand continuous evaluation to guide future initiatives. In addition, the resilience and maintenance of plant and animals communities in restored forests in tropical regions are closely related to the recovery of animal-mediated interactions. We provide, in this article, raw data related to the reproductive ecology of Inga vera, one of the most common tree species used in forest restoration initiatives in the Brazilian northeastern Atlantic forest. Specifically, we explore data on phenology, nectar dynamics and reproductive success of I. vera in natural and planted (monospecific) populations. This data article is related to the research article “Pollination partial recovery across monospecific plantations of a native tree (Inga vera, Leguminosae) in the Atlantic forest: lessons for restoration” (Cruz-Neto et al., 2018) [1].

Biological soil crusts (biocrusts) have been recognized as key ecological players in arid and semiarid regions at both local and global scales. They are important biodiversity components, provide critical ecosystem services, and strongly influence soil-plant relationships, and successional trajectories via facilitative, competitive, and edaphic engineering effects. Despite these important ecological roles, very little is known about biocrusts in seasonally dry tropical forests. Here we present a first baseline study on biocrust cover and ecosystem service provision in a human-modified landscape of the Brazilian Caatinga, South America's largest tropical dry forest. More specifically, we explored (1) across a network of 34 0.1 ha permanent plots the impact of disturbance, soil, precipitation, and vegetation-related parameters on biocrust cover in different stages of forest regeneration, and (2) the effect of disturbance on species composition, growth and soil organic carbon sequestration comparing early and late successional communities in two case study sites at opposite ends of the disturbance gradient. Our findings revealed that biocrusts are a conspicuous component of the Caatinga ecosystem with at least 50 different taxa of cyanobacteria, algae, lichens and bryophytes (cyanobacteria and bryophytes dominating) covering nearly 10% of the total land surface and doubling soil organic carbon content relative to bare topsoil. High litter cover, high disturbance by goats, and low soil compaction were the leading drivers for reduced biocrust cover, while precipitation was not associated Second-growth forests supported anequally spaced biocrust cover, while in old-growth-forests biocrust cover was patchy. Disturbance reduced biocrust growth by two thirds and carbon sequestration by half. In synthesis, biocrusts increase soil organic carbon (SOC) in dry forests and as they double the SOC content in disturbed areas, may be capable of counterbalancing disturbance-induced soil degradation in this ecosystem. As they fix and fertilize depauperated soils, they may play a substantial role in vegetation regeneration in the human-modified Caatinga, and may have an extended ecological role due to the ever-increasing human encroachment on natural landscapes. Even though biocrusts benefit from human presence in dry forests, high levels of anthropogenic disturbance could threaten biocrust-provided ecosystem services, and call for further, in-depth studies to elucidate the underlying mechanisms.

Global climate change alters the dynamic of natural ecosystems and directly affects species distributions, persistence and diversity. The impacts of climate change may lead to dramatic changes in biotic interactions, such as pollination and seed dispersal. Life history traits are extremely important to consider the vulnerability of a species to climate change, producing more robust models than those based primarily on species distributions. Here, we hypothesized that rising temperatures and aridity will reduce suitable habitats for the endemic flora of the Caatinga, the most diverse dry tropical forest on Earth. Specifically, species with specialized reproductive traits (e.g. vertebrate pollination, biotic dispersal, obligatory cross-pollination) should be more affected by climate change than those with generalist traits. We performed two ecological niche models (current and future) to simulate the effects of climate change on the distribution area of endemic species in relation to life-history traits. We used the MIROC-ESM and CCSM4 models for both intermediate (RCP4.5) and highest predicted (RCP8.5) GHG emission scenarios, with a resolution of 30' (~1 km2). Habitat with high occurrence probability (>80%) of endemic species will be reduced (up to ~10% for trees, ~13% for non-arboreous, 10-28% for species with any pollination/reproductive system), with the greatest reductions for species with specialized reproductive traits. In addition, the likely concentration of endemic plants in the extreme northeastern portion of the Caatinga, in more mesic areas, coincides with the currently most human-modified areas of the ecosystem, which combined with climate change will further contract suitable habitats of endemic species. In conclusion, plant species endemic to the Caatinga are highly vulnerable to even conservative scenarios of future climate change and may lose much of their climatic envelopes. New protected areas should be located in the northeastern portion of the Caatinga, which hosts a more favorable climate, but is currently exposed to escalating agricultural intensification.

This study provides an approximation of the potential impact of fuelwood harvesting in one of the most threatened tropical biodiversity conservation hotspots, the northern portion of the Brazilian Atlantic Forest. We test the relationship between fuelwood consumption and per capita income for 270 households distributed over 7 rural settlements. In general 76% of the households use fuelwood regularly and consume on average 686 kg/person/year of tree biomass, poorer people, however, consume 961 kg/person/year. Harvesting is concentrated to a few early successional species. Yet, annual rural population demand from 210 municipalities may reach 303,793 tons, equivalent to 1.2 to 2.1 thousand hectares of tropical forest. Fuelwood harvesting cannot be ignored as a major and chronic source of forest degradation in highly fragmented and densely populated landscapes and conciliating biodiversity conservation with poverty amelioration is an urgent task.

In this essay we examine some of the processes affecting the composition and structure of tree species assemblages and, consequently, what we can expect from secondary-forest stands as an element of human-modified landscapes and as an opportunity for biodiversity persistence in this ecological context. Based on the available information, it is reasonable to predict that in some landscapes or biotas: (1) small forest remnants degenerate and support plant assemblages with attributes similar to those observed in early and intermediate-aged regenerating stands, while secondary-forest stands move from initial to more advanced successional stages; (2) collectively, remnant/stand attributes and landscape integrity define the pace through which degeneration proceeds, but also the potential for regeneration; (3) at the landscape spatial scale, remnants and stands tend to converge in terms of structure, but also in terms of taxonomic and functional composition. In other words, remnants degenerate and secondary-forest stands regenerate toward a sort of ‘climax community’, which is conditioned by the physical and biological integrity of both patch and landscape. Considering secondary forests in the conceptual, ecological and spatial framework of human-modified landscapes may help us to understand and maximize the conservation services provided by this habitat as it proliferates through human-modified landscapes.

Em um fragmento urbano de Floresta Ombrófila Densa Montana no Estado do Espírito Santo (Sudeste do Brasil), foram avaliados o padrão de frugivoria e as proporções de remoção, predação e armazenamento de frutos por Guerlinguetus ingrami, em relação a cinco espécies de palmeira (Syagrus pseudococos, S. ruschiana, Bactris setosa, Polyandrococos caudescens e Euterpe edulis). As espécies de Arecaceae enquadram-se na síndrome associada à dispersão por G. ingrami, na qual as espécies de plantas apresentam alta produção, grandes frutos com poucas sementes envolvidas por endocarpos resistentes e que não são usadas por outros predadores de sementes arborícolas. Os resultados apontaram que existem diferenças no padrão de frugivoria da espécie G. ingrami quando comparadas com as de espécies com a mesma síndrome; aquelas que possuem frutos maiores apresentaram maior taxa de remoção e de armazenamento de seus diásporos. E, devido à especificidade exibida por G. ingrami na atividade de dispersão de sementes, este roedor deverá atuar apenas em trocas compensatórias específicas em pequenos fragmentos defaunados. Portanto, a seletividade de G. ingrami poderia indicar que o seu papel como dispersor em pequenos fragmentos estaria restrito em função da maior probabilidade de mortalidade associada às plantas preferencialmente dispersas por essa espécie, e sua atuação como predador de sementes deve ser quantificada para que os seus efeitos, em pequenos fragmentos, sejam mais bem compreendidos.This study investigated the fruvigory pattern of Guerlinguetus ingrami, considering the removal, predation and caching of the fruits of palm species (Syagrus pseudococos, S. ruschiana, Bactris setosa, Polyandrococos caudescens and Euterpe edulis) in an urban forest fragment of the montane Atlantic forest in the state of Espírito Santo, Southeastern Brazil. These palm species show characteristics theoretically expected to be seen in plants dispersed by squirrels (trees with a high productivity and whose fruits are large, with few seeds covered by rigid endocarps and that are not utilized by other arborean seed predators). Here we describe differences in the frugivory pattern exhibited by G. ingrami towards plants with the same dispersal syndrome. The diaspores of species with larger fruits were removed and cached by the squirrel at rates higher than the palms with small fruits. As a result of the high specificity showed by the squirrel's activities related to seed dispersal, this rodent should be important in compensatory shifts only in small, defaunated forest fragments. Therefore, the selectivity of G. ingrami could indicate that its role as a seed dispersor into small forest fragments would be restricted, due to the grater likelihood of mortality associated to the plants scattered by this species. The role of G. ingrami as a seed predator must be quantified for the effects of its behavioral activities in small fragments to be understood.

O insucesso da maioria das iniciativas de restauração de florestas naturalmente biodiversas como a Mata Atlântica desencadeou um movimento intenso de discussão sobre a ciência e prática da restauração ecológica no Estado de São Paulo. Isso convergiu na construção participativa de uma resolução estadual de caráter técnico e orientador para restauração, a qual tem sido revisada e atualizada periodicamente em workshops que reúnem mais de 200 profissionais em cada evento. Essa resolução objetivou potencializar o estabelecimento de florestas biologicamente viáveis e com riqueza de espécies vegetais condizente com a dos ecossistemas de referência, a fim de garantir a persistência das florestas restauradas e proteger a biodiversidade nativa. As contribuições dessa resolução para o aperfeiçoamento e estímulo das ações de restauração são hoje evidentes. Entre 2003 e 2008, período de discussão dessa resolução, a produção de mudas de espécies arbustivas e arbóreas nativas no Estado cresceu de 13.000.000 (55 viveiros) para 33.000.000 (114 viveiros) por ano, e o número médio de espécies produzidas nos viveiros também aumentou de 30 para mais de 80, refletindo o crescimento das ações de restauração. Do ponto de vista deste estudo, esse instrumento legal tem servido como mecanismo legítimo de política pública ambiental e de proteção dos interesses coletivos da sociedade. Particularmente, ele guia e orienta a maior parte dos investimentos em restauração ecológica e aumenta as perspectivas de maximização dos benefícios para a sociedade, que podem e devem ser obtidos com a restauração, incluindo a persistência da biodiversidade nas paisagens antrópicas tropicais.The failure of most efforts undertaken to restore natural high-diversity tropical forests, like the Atlantic Forest, has resulted in a very intense round of discussions on the science and best-practice of ecological restoration in the state of São Paulo, southeastern Brazil. This culminated in the participatory elaboration of a state resolution concerning technical and orientation aspects for restoration activities, which has been reviewed and updated periodically in workshops that bring together more than 200 professionals. The aim of this resolution was to maximize the establishment of biologically viable forests, with plant richness consistent with the reference ecosystem, to ensure the persistence of restored forests and protect native biodiversity. The contributions of this resolution for the improvement and stimulation of restoration actions are evident today. Between 2003 and 2008, when the resolution was heavily discussed, seedling production of native shrubs and trees in the state increased from 13,000,000 (55 nurseries) to 33,000,000 (114 nurseries) per year, and average number of plant species produced in nurseries also increased from 30 to over 80, reflecting the increase of restoration actions. In our view, the existing legal instrument has served well as a mechanism to accompany environmental public policy aimed at protection of the collective interests of society. In particular, it guides and orients the bulk of investments in ecological restoration and enhances the prospects for maximizing the societal benefits that can and should be obtained from restoration activities, including the persistence of biodiversity in human-modified tropical landscapes.

The effects of human disturbance on biodiversity can be mediated by environmental conditions, such as water availability, climate and nutrients. In general, disturbed, dry or nutrient-depleted soils areas tend to have lower taxonomic diversity. However, little is known about how these environmental conditions affect functional composition and intraspecific variability in tropical dry forests. We studied a seasonally dry tropical forest (SDTF) under chronic anthropogenic disturbance (CAD) along rainfall and soil nutrient gradients to understand how these factors influence the taxonomic and functional composition. Specifically we evaluated two aspects of CAD, wood extraction and livestock pressure (goat and cattle grazing), along soil fertility and rainfall gradients on shrub and tree traits, considering species turnover and intraspecific variability. In addition, we also tested how the traits of eight populations of the most frequent species are affected by wood extraction, livestock pressure, rainfall and soil fertility. In general, although CAD and environmental gradients affected each trait of the most widespread species differently, the most abundant species also had a greater variation of traits. Considering species turnover, wood extraction is associated with species with a smaller leaf area and lower investment in leaf mass, probably due to the indirect effects of this disturbance type on the vegetation, i.e. the removal of branches and woody debris clears the vegetation, favouring species that minimize water loss. Livestock pressure, on the other hand, affected intraspecific variation: the herbivory caused by goats and cattle promoted individuals which invest more in wood density and leaf mass. In this case, the change of functional composition observed is a direct effect of the disturbance, such as the decrease of palatable plant abundance by goat and cattle herbivory. In synthesis, CAD, rainfall and soil fertility can affect trait distribution at community and species levels, which can have significant implications for the ecosystem functioning of SDTF under increasing levels of disturbance, climate change and soil nutrient depletion.

We examine the effects of forest fragmentation on the structure and composition of tree assemblages within three seasonal and aseasonal forest types of southern Brazil, including evergreen, Araucaria, and deciduous forests. We sampled three southernmost Atlantic Forest landscapes, including the largest continuous forest protected areas within each forest type. Tree assemblages in each forest type were sampled within 10 plots of 0.1 ha in both continuous forests and 10 adjacent forest fragments. All trees within each plot were assigned to trait categories describing their regeneration strategy, vertical stratification, seed-dispersal mode, seed size, and wood density. We detected differences among both forest types and landscape contexts in terms of overall tree species richness, and the density and species richness of different functional groups in terms of regeneration strategy, seed dispersal mode and woody density. Overall, evergreen forest fragments exhibited the largest deviations from continuous forest plots in assemblage structure. Evergreen, Araucaria and deciduous forests diverge in the functional composition of tree floras, particularly in relation to regeneration strategy and stress tolerance. By supporting a more diversified light-demanding and stress-tolerant flora with reduced richness and abundance of shade-tolerant, old-growth species, both deciduous and Araucaria forest tree assemblages are more intrinsically resilient to contemporary human-disturbances, including fragmentation-induced edge effects, in terms of species erosion and functional shifts. We suggest that these intrinsic differences in the direction and magnitude of responses to changes in landscape structure between forest types should guide a wide range of conservation strategies in restoring fragmented tropical forest landscapes worldwide.

Amazonian rainforests sustain some of the richest tree communities on Earth, but their ecological and evolutionary responses to human threats remain poorly known. We used one of the largest experimental datasets currently available on tree dynamics in fragmented tropical forests and a recent phylogeny of angiosperms to test whether tree communities have lost phylogenetic diversity since their isolation about two decades previously. Our findings revealed an overall trend toward phylogenetic impoverishment across the experimentally fragmented landscape, irrespective of whether tree communities were in 1-ha, 10-ha, or 100-ha forest fragments, near forest edges, or in continuous forest. The magnitude of the phylogenetic diversity loss was low (

Deforestation and forest fragmentation are known major causes of nonrandom extinction, but there is no information about their impact on the phylogenetic diversity of the remaining species assemblages. Using a large vegetation dataset from an old hyper-fragmented landscape in the Brazilian Atlantic rainforest we assess whether the local extirpation of tree species and functional impoverishment of tree assemblages reduce the phylogenetic diversity of the remaining tree assemblages. We detected a significant loss of tree phylogenetic diversity in forest edges, but not in core areas of small (

Functional diversity has been postulated to be critical for the maintenance of ecosystem functioning, but the way it can be disrupted by human-related disturbances remains poorly investigated. Here we test the hypothesis that habitat fragmentation changes the relative contribution of tree species within categories of reproductive traits (frequency of traits) and reduces the functional diversity of tree assemblages. The study was carried out in an old and severely fragmented landscape of the Brazilian Atlantic forest. We used published information and field observations to obtain the frequency of tree species and individuals within 50 categories of reproductive traits (distributed in four major classes: pollination systems, floral biology, sexual systems, and reproductive systems) in 10 fragments and 10 tracts of forest interior (control plots). As hypothesized, populations in fragments and control plots differed substantially in the representation of the four major classes of reproductive traits (more than 50% of the categories investigated). The most conspicuous differences were the lack of three pollination systems in fragments--pollination by birds, flies and non-flying mammals--and that fragments had a higher frequency of both species and individuals pollinated by generalist vectors. Hermaphroditic species predominate in both habitats, although their relative abundances were higher in fragments. On the contrary, self-incompatible species were underrepresented in fragments. Moreover, fragments showed lower functional diversity (H' scores) for pollination systems (-30.3%), floral types (-23.6%), and floral sizes (-20.8%) in comparison to control plots. In contrast to the overwhelming effect of fragmentation, patch and landscape metrics such as patch size and forest cover played a minor role on the frequency of traits. Our results suggest that habitat fragmentation promotes a marked shift in the relative abundance of tree reproductive traits and greatly reduces the functional diversity of tree assemblages in fragmented landscapes.

O objetivo deste estudo é caracterizar alguns dos processos envolvidos na sucessão secundária da floresta ombrófila densa montana, em uma área no Núcleo Santa Virgínia, município de São Luiz do Paraitinga, SP. Através do método de parcelas, foram amostradas duas áreas de floresta secundária, uma com aproximadamente quinze anos e a outra entre vinte e cinco e trinta anos de idade. A análise dos dados revelou modificações na composição florística e na estrutura da comunidade e das populações, bem como modificações na importância dos grupos funcionais e das síndromes de dispersão de propágulos.

Este trabalho objetiva avaliar o papel de uma floresta de Eucalyptus spp, na recuperação da floresta nativa, buscando subsídios para o manejo destes povoamentos no Núcleo Santa Virgínía, São Luiz do Paraitinga, SP. Através do uso de parcelas lançadas ao acaso, foram amostrados três trechos da floresta implantada. A análise dos dados revelou que o sub-bosque desta floresta apresenta um padrão sucessional em forma de mosaico, onde coexistem áreas ricas em espécies nativas de diferentes grupos ecológicos, com áreas desprovidas de vegetação arbórea. O zoneamento, com base na regeneração natural, parece ser a alternativa mais adequada ao manejo do reflorestamento.

O objetivo deste trabalho é discutir alguns aspectos da sucessão secundária na floresta atlântica através da caracterização e análise do desenvolvimento histórico de um trecho de floresta secundária, no Núcleo Santa Virgínia, São Luiz do Paraitinga, SP. Foram encontradas quarenta e seis espécies pertencentes a vinte e duas famílias botânicas, sendo que dez espécies foram classificadas como pioneiras, treze como secundárias e vinte e três espécies como típicas de sub-bosque. A maioria das espécies apresentou síndrome de dispersão por animais. O padrão sucessional descrito, apresenta similaridade com outros padrões sucessionais apresentados para a floresta ombrófila densa no Sul e Sudeste do Brasil.