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Natural enemies play an important role in controlling plant population growth and vegetation dynamics. Tropical rainforests host the greatest diversity of herbivores, from large mammalian ungulates to microscopic pathogens, generating and maintaining plant diversity.By feeding on the same resources, large mammalian herbivores may interfere with plant consumption and leaf damage by important enemy guilds such as invertebrate herbivores and pathogens, triggering indirect trophic cascades. However, the impact of local extinctions of large herbivores on plant–enemy interactions is relatively unknown.We experimentally tested the effects of defaunation of large mammalian herbivores (e.g. peccaries, tapirs and brocket deer; hereafter, large herbivores) on the leaf damage of 3350 understorey plants in tropical rainforests of Brazil. We examined leaf damage in 10,050 leaves from 333 morphospecies by assigning the area consumed or damaged by five guilds of insect herbivores and leaf pathogens within 86 paired open‐closed plots and investigating the joint effects of defaunation and plant phylogenetic diversity.Plants released from large herbivores had 9% less leaf damage; this difference was due to the lower leaf pathogens incidence (29%) rather than insect herbivory. Evolutionary distinctness was positively correlated with leaf damage in a similar way in all treatments, suggesting additive effects of defaunation and phylogenetic diversity. Total and pathogenic leaf damage (but not insect damage) decreased with plant richness across treatments, and large herbivores exclusion resulted in increased plant species richness. This suggests that large herbivores exclusion leads to a dilution of total and pathogens' leaf damage by increasing plant species richness.Our results suggest that indirect effects of large herbivores decrease the dilution potential of plant communities against pathogens and rather reinforce their top‐down impact on vegetation, demonstrating a previously overlooked cascading effect of large herbivore extinction on forest ecosystems.Synthesis: The extinction of large mammalian herbivores can lead to a decrease in pathogen‐driven leaf damage, a previously unknown indirect effect in forest ecosystems, which might have consequences for plant fitness and ultimately for plant diversity. Large herbivores and plant pathogens might have synergistic effects in regulating the diversity of plant communities in some of the most diverse ecosystems on Earth. [ABSTRACT FROM AUTHOR]

Anthropogenic impacts on biodiversity can lead to biotic homogenization (BH) and biotic differentiation (BD). BH is a process of increasing similarity in community composition (including taxonomic, functional, and phylogenetic components), whereas BD is a process of decreasing similarity over space and time. Here, we conducted a systematic review of BH and BD in plant communities in tropical and subtropical forests to identify trends and knowledge gaps. Our bibliometric search in the Web of Science returned 1989 papers, of which 151 matched our criteria and were included in the analysis. The Neotropical region had the largest number of articles, and Brazil was the most represented country with 92 studies. Regarding the type of change, homogenization was more frequent than differentiation (noted in 69.6% of publications). The taxonomic diversity component was measured more often than functional and phylogenetic diversity components. Most studies (75.6%) assessed homogenization and differentiation based on a single observation in time; as opposed to few studies that monitored plant community over multiple years. Forest fragmentation was cited as the main determinant of homogenization and differentiation processes (57.2% of articles). Our results highlight the importance of evaluating community composition over time and more than taxonomic components (i.e., functional and phylogenetic) to advance understanding of homogenization and differentiation. Both processes were scale dependent and not mutually exclusive. As such, future research should consider differentiation as a potential transition phase to homogenization and that potential differences in both processes may depend on the spatial and temporal scale adopted. Understanding the complexity and causes of homogenization and differentiation is essential for biodiversity conservation in a world increasingly affected by anthropogenic disturbances. [ABSTRACT FROM AUTHOR]

Plant phenology has been shifting dramatically in response to climate change, a shift that may have significant and widespread ecological consequences. Of particular concern are tropical biomes, which represent the most biodiverse and imperilled regions of the world. However, compared to temperate floras, we know little about phenological responses of tropical plants because long‐term observational datasets from the tropics are sparse.Herbarium specimens have greatly increased our phenological knowledge in temperate regions, but similar data have been underutilized in the tropics and their suitability for this purpose has not been broadly validated. Here, we compare phenological estimates derived from field observational data (i.e. plot surveys) and herbarium specimens at various spatial and taxonomic scales to determine whether specimens can provide accurate estimations of reproductive timing and its spatial variation.Here, we demonstrate that phenological estimates from field observations and herbarium specimens coincide well. Fewer than 5% of the species exhibited significant differences between flowering periods inferred from field observations versus specimens regardless of spatial aggregation. In contrast to studies based on field records, herbarium specimens sampled much larger geographic and climatic ranges, as has been documented previously for temperate plants, and effectively captured phenological responses across varied environments.Synthesis. Herbarium specimens are verified to be a vital resource for closing the gap in our phenological knowledge of tropical systems. Tropical plant reproductive phenology inferred from herbarium records is widely congruent with field observations, suggesting that they can and should be used to investigate phenological variation and their associated environmental cues more broadly across tropical biomes. [ABSTRACT FROM AUTHOR]

Question: Individual plants of some highly diverse angiosperm families occur in aggregated spatial patterns in tropical plant communities, which have been defined as species swarms. Although this spatial aggregation seems paradoxical, because related species should segregate in space owing to expected ecological similarities, it has yet to be tested. We assessed whether species of the family Rubiaceae segregate in space in the understorey of a tropical plant community. Location: An Atlantic Forest fragment in southeast Brazil. Methods: We surveyed all local aggregates of Rubiaceae species within an 18.75‐ha plot across a topographic gradient. Based on the species abundance distribution, we used the 10 most abundant species to model their spatial patterns using univariate and bivariate spline spatial correlations. Bubble graphs were used to show how these species were distributed across the gradient. Results: A total of 12,258 individuals of 47 species were found distributed in 543 local aggregates. The 10 studied species corresponded to 86% of the total abundance and were aggregated in space, at distances from 0 to 10–300 m. Pairwise comparisons revealed a segregation pattern at scales ranging from 0 to 10–230 m. Local aggregates were strongly dominated by a single species, whereas many other species occurred at very low abundances. Conclusion: The studied species of Rubiaceae shared the understorey environment by occupying different portions of available space. Habitat preferences, negative interactions, dispersal limitation and priority effects may explain the observed spatial patterns. Swarms are not paradoxical because species of Rubiaceae use different microhabitats within the forest understorey. [ABSTRACT FROM AUTHOR]

Plants emit a broad number of Biogenic Volatile Organic Compounds (BVOCs) that can impact urban ozone (O3) production. Conversely, the O3 is a phytotoxic pollutant that causes unknown alterations in BVOC emissions from native plants. In this sense, here, we characterized the constitutive and O3-induced BVOCs for two (2dO3) and four (4dO3) days of exposure (O3 dose 80 ppb) and evaluated the O3 response by histochemical techniques to detect programmed cell death (PCD) and hydrogen peroxide (H2O2) in three Brazilian native species. Croton floribundus Spreng, Astronium graveolens Jacq, and Piptadenia gonoacantha (Mart.) JF Macbr, from different groups of ecological succession (acquisitive and conservative), different carbon-saving defense strategies, and specific BVOC emissions. The three species emitted a very diverse BVOC composition: monoterpenes (MON), sesquiterpenes (SEQ), green leaf volatiles (GLV), and other compounds (OTC). C. floribundus is more acquisitive than A. graveolens. Their most representative BVOCs were methyl salicylate—MeSA (OTC), (Z) 3-hexenal, and (E)-2-hexenal (GLV), γ-elemene and (−)-β-bourbonene (SEQ) β-phellandrene and D-limonene (MON), while in A. graveolens were nonanal and decanal (OTC), and α-pinene (MON). Piptadenia gonoachanta is more conservative, and the BVOC blend was limited to MeSA (OTC), (E)-2-hexenal (GLV), and β-Phellandrene (MON). The O3 affected BVOCs and histochemical traits of the three species in different ways. Croton floribundus was the most O3 tolerant species and considered as an SEQ emitter. It efficiently reacted to O3 stress after 2dO3, verified by a high alteration of BVOC emission, the emergence of the compounds such as α-Ionone and trans-ß-Ionone, and the absence of H2O2 detection. On the contrary, A. graveolens , a MON-emitter, was affected by 2dO3 and 4dO3, showing increasing emissions of α-pinene and β-myrcene, (MON), γ-muurolene and β-cadinene (SEQ) and H2O2 accumulation. Piptadenia gonoachanta was the most sensitive and did not respond to BVOCs emission, but PCD and H2O2 were highly evidenced. Our results indicate that the BVOC blend emission, combined with histochemical observations, is a powerful tool to confirm the species' tolerance to O3. Furthermore, our findings suggest that BVOC emission is a trade-off associated with different resource strategies of species indicated by the changes in the quality and quantity of BVOC emission for each species. [ABSTRACT FROM AUTHOR]

Context: In human-altered landscapes, native vegetation cover is essential for pollination maintenance. Heterogeneous land-uses may provide complementary resources for some pollinator species, contributing to the connectivity of landscapes and the maintenance of pollination. Objectives: To investigate the effect of forest cover and non-forest landscape heterogeneity on pollination of native understory forest plant assemblages. Methods: We quantified pollen deposited on understory native flowers in gradients of forest cover and heterogeneity of land-uses (Shannon–Wiener diversity index) in a central forest patch in 14 landscapes. Results: Forest cover and the non-forest heterogeneity of land-uses interacted, favoring pollination in landscapes with high amount of forest and low heterogeneity, and in landscapes with low amount of forest and high heterogeneity. Forest promotes high-quality habitats and higher connectivity for pollinators, increasing pollination. Forest cover and non-forest landscape heterogeneity seemed to increase pollinator efficiency, since pollination increased regardless of pollinator diversity. In landscapes with a low amount of forest, high land-use heterogeneity may partially compensate for forest loss due to land-uses that offered complementary resources for the maintenance of pollinators and pollination. Conclusions: We have seen that pollination is favored by forest cover and the interaction between native forest and other land-uses that can add complementary resources and landscape connectivity to pollinators. For management policies, priority should be on the maintenance and increase of native forest cover in the landscapes, followed by promoting heterogeneity of other favorable land-uses to pollinators. [ABSTRACT FROM AUTHOR]

Plants adapted to different habitats exhibit differences in functional traits and these characteristics are influenced by soil properties. We tested the hypothesis that soil resource availability influences the functional traits of plants, affecting therefore herbivory levels. We examined three Byrsonima plant species with different life forms that occurred across a distinct edaphic habitat along the Doce River Basin, South-eastern Brazil. We characterized habitats according to soil nutrient concentration and measured functional characteristics of crown architecture, leaf nutrients, sclerophylly, leaf area and leaf density. In addition, we evaluated how these variables influenced herbivory levels of congeneric plants. Our data show that species along a gradient of soil nutrients have functional characteristics influenced by habitat, which in turn affect herbivory levels. By comparing congeners with different life forms found along a stress-gradient of continuous habitats, we describe a corresponding gradient of plant functional traits and tissue consumption by herbivorous insects. [ABSTRACT FROM AUTHOR]

Benjamin Corenwinder (1820-1884) was a French scientist and manufacturer, without a formal academic education, who made important contributions to phenomena related to vegetable physiology, the cultivation of beetroot, and the analysis of tropical fruit. He studied in particular plant respiration and the contribution of the different organs of the plant. He found that plants, in their early age, always provided cinders rich in phosphoric acid and after maturity the stems, leaves and roots show no presence of this acid. The events of germination did not consist only in the transformation of starch into sugar; gluten played an important role in the process. Young leaves respired through their nitrogenous part and assimilated carbon with the aid of carbonaceous matters that become organized in their tissues through the intermediate help of chlorophyll. Respiration and assimilation of carbon took place simultaneously but the latter became so attenuated that it could completely mask the effects of the former. Corenwinder carried a detailed study of the growth of beetroot, including the effect of fertilizers, particularly that of sodium nitrate. He also studied a variety of tropical plants, such as banana and chestnut of Brazil.. [ABSTRACT FROM AUTHOR]

Question: Climate, particularly precipitation, is the primary factor driving tropical plant phenology because of its relevant role in regulating water availability. However, differences in soil physicochemical properties can also drive resource availability, potentially affecting plant phenology, especially under similar environments in terms of rainfall regime. We determined whether the seasonality and synchrony of the vegetative and reproductive phenophases differ along a grassland–savanna–forest gradient under the same climate regime in a Neotropical seasonal ecosystem. We hypothesized that species growing on shallow, nutrient-impoverished soils have a higher capacity to respond to precipitation pulses than those on rich soils. Location: Serra do Cipó, southeastern Brazil. Methods: We quantified soil physicochemical properties associated with fertility and water retention of the grassland (campo rupestre), savanna (cerrado) and forest, and determined the phenological strategies of 70 species across the three vegetation types by monitoring vegetative and reproductive phenophases over one year. For each phenophase, in each vegetation type, we evaluated the seasonality and synchrony of phenological patterns. We quantified the phylogenetic signal for phenophases to disentangle the relative roles of historical vs ecological drivers of plant phenology. Results: Soils from campo rupestre were more nutrient- and water-limited than those of cerrado and forest. Cerrado and forest communities had similar phenological strategies, whereas species from campo rupestre showed strategies that maximize resource acquisition and conservation. In the cerrado and forest, leafing and flowering patterns were seasonal, with leaf flushing and flowering peaking at the onset of the rainy season and leaf senescence in the dry season. Conversely, species from campo rupestre showed continuous leafing and flowering patterns, while fruiting was seasonal. Phenophases did not show a phylogenetic signal. Conclusions: We demonstrated changes in vegetative and reproductive phenology that are likely associated with variations in soil physicochemical properties. We argue that more severe edaphic filters may have shaped different phenological patterns in campo rupestre. [ABSTRACT FROM AUTHOR]

Bibliometric analyzes are a coherent way of working to answer the needs and possibilities of scientific research. Currently, there is no bibliometric review on Seed Pathology, so the production of an article with this change is the objective of this work. For this, the Web of Science (WOS) database was used; CiteSpace and VOSviewer as statistical programs; with a use of the following aspects: a. "Seed pathology" to schedule a survey; B. 2000-2020 period; ç. articles only. As results, seventy articles were selected; 45% of these are in the area of agriculture; the most productive year was 2014 (14.28% of the total); an EMBRAPA was a more relevant institution (25.71% of the total); CNPq is the largest financier (20.00% of the total); the highlighted author was Dr. José da Cruz Machado (12.25% of the total); Brazil stood out in the world (82.85% of the total) and the Tropical Plant Pathology journal was the most relevant (17.14% of the total). The greatest emphasis of research carried out was on the theme of detection (48.50% of the total) and an agricultural crop with greater evidence was Phaseolus vulgaris (16.00% of the total). Research on agricultural crops, pathogens and emerging identification techniques are used for sustainable agricultural production in the present and the future, without, however, forgetting the main problems still unresolved in the field of seed pathology. Bibliographies are tools that allow the identification of applications that can be further explored within the scope of scientific resear. [ABSTRACT FROM AUTHOR]

• We focused on the diversity of endophytic fungi of carapichea ipecacuanha. • One hundred and seventy-six fungal isolates were recovered identified as 28 taxa. • Colletotrichum was the dominant genus. Colletotrichum gigasporum and colletotrichum sp. 1 were the most dominant taxa. • The findings indicate that tropical plants are a rich reservoir of fungal diversity. We focused on the taxonomy and diversity of endophytic fungi associated with the threatened medicinal plant Carapichea ipecacuanha , present in a native fragment of the Atlantic Rain Forest in Brazil. One hundred and seventy-six fungal isolates were recovered from leaf, stem, and root tissues of C. ipecacuanha. The isolates comprised 28 taxa of Colletotrichum, Ceratobasidium, Fusarium, Trichoderma, Diaporthe, Pochonia, Calonectria , and Xylaria. Colletotrichum was the dominant genus. Colletotrichum gigasporum and Colletotrichum sp. 1 were the most dominant taxa, which occurred systematically in all plant tissues. In contrast, Calonectria lateralis, Fusarium delphinoides, Xylaria sp., and Diaporthe spp. occurred as singlets. We detected a rich and diverse endophytic fungal community in the different tissues of C. ipecacuanha dominated by genera recognised as phytopathogens and decomposers. The findings indicate that tropical plants are a rich reservoir of fungal diversity, which is also threatened by the devastation of the natural tropical rainforest environments. [ABSTRACT FROM AUTHOR]

The increasing global demand for electricity has led to a significant increase in the search for low-impact alternative sources, with solar photovoltaic being identified as one of the most feasible options. However, photovoltaic power plants require large ground areas, which represent a major constraint. If the panels are installed on water bodies, this restriction may be avoided. In this work, a simulation was performed to assess the potential of floating photovoltaic power generation in the tropical Gavião reservoir, located in the Northeast of Brazil. A payback analysis indicated that the investment in construction of the system is fully recovered in eight years, and that water losses due to evaporation can be reduced by approximately 2.6 × 106 m³/year, sufficient to supply roughly 50,000 people. [ABSTRACT FROM AUTHOR]

As part of the search for sustainability in production systems, systems of annual crops intercropped with tropical forage plants have recently been used for silage production. Therefore, in the present study we aimed to evaluate the dry matter yield, fermentative parameters and nutritional value of the silage of sorghum intercropped with Paiaguas palisadegrass in different forage systems and maturity stages in a crop-livestock integration system. The experiment was conducted at the Goiano Federal Institute (Instituto Federal Goiano), Rio Verde Campus, Goiás, Brazil, in a completely randomised design with four replications in a 5 × 3 factorial arrangement with five forage systems (monocropped sorghum, monocropped Paiaguas palisadegrass, sorghum row intercropped with Paiaguas palisadegrass, sorghum inter-row intercropped with Paiaguas palisadegrass and sorghum oversown and intercropped with Paiaguas palisadegrass) and three maturity stages of the sorghum (milky, soft dough and hard dough). The results show that for all sowing methods, the silages of the intercropping systems harvested in the hard-dough stage provide a higher yield per area than did the monocropped sorghum and Paiaguas palisadegrass. The intercropping of sorghum with Paiaguas palisadegrass in crop-livestock integration systems could become an important option for the production of silage because intercropping minimises the inconveniences resulting from the fermentation process of the silage of monocropped grasses and improves the quality of the silage. These findings show this intercropping method to be advantageous strategy for the production of supplemental roughage in addition to contributing to the formation of pasture after the crops have been harvested for ensiling. Silage production of sustainably integrated systems in ruminant feed. Evaluate silage of sorghum intercropped Paiaguas palisadegrass in different forage systems and maturity stages. The silages of the intercropping systems provide a higher yield per area and best nutritional characteristics of silages. The intercropping could become important option for the production of silage in addition to contributing to the formation of pasture after the crops have been harvested for ensiling maximizing nutrient production per area in sustainable manner. [ABSTRACT FROM AUTHOR]

Premise: Plant genomes vary in size and complexity due in part to polyploidization. Latitudinal analyses of polyploidy are biased toward floras of temperate regions, with much less research done in the tropics. Lippia alba has been described as a tropical polyploid complex with diploid, triploid, tetraploid, and hexaploid accessions. However, no data regarding relationships among the ploidal levels and their origins have been reported. Our goals are to clarify the relationships among accessions of Lippia alba and the origins of each ploidal level. Methods: We investigated 98 samples representing all five geographical regions of Brazil and all ploidal levels using microsatellite (SSR) allelic variation and DNA sequences of ITS and trnL‐F. Nine morphological structures were analyzed from 33 herbarium samples, and the chemical compounds of 78 accessions were analyzed by GC–MS. Results: Genetic distance analysis, the alignment block pattern, as well as RAxML and Bayesian trees showed that accessions grouped by ploidal level. The triploids form a well‐defined group that originated from a single group of diploids. The tetraploids and hexaploid grouped together in SSR and trnL‐F analyses. The recovered groups agree with chemical data and morphology. Conclusions: The accessions grouped by ploidal level. Only one origin of triploids from a single group of diploids was observed. The tetraploid origin is uncertain; however, it appears to have contributed to the origin of the hexaploid. This framework reveals linkages among the ploidal levels, providing new insights into the evolution of a polyploid complex of tropical plants. [ABSTRACT FROM AUTHOR]

Climate regulates the fern phenology and climatic triggers influence plants from tropical and subtropical regions differently. Ferns depend on climate to regulate their life cycle, because they do not require animal interaction to reproduce. Through the pioneering study of the phenology of Araucaria forest understory in subtropical climate of Brazil, our main aims were (i) to verify which climatic variables influenced the phenological pattern of the community, (ii) to identify the differences in seasonality of ferns in distinct climatic zones of Brazil, and (iii) to compare the phenological pattern of ferns growing in other subtropical regions of the world. In an Araucaria forest fragment, we monitored the phenology of the fern community (leaf production, leaf senescence, and sporangium formation) over 2 years. At the same time, we collected photoperiod, temperature, and precipitation data. Ferns phenology was classified as continuous, discontinuous, regular, and irregular. Our results showed photoperiod and mean temperature as the best predictors for phenology. The reproductive event was seasonal, and the fern community presented themselves as continuous, irregular (activity index), and regular (intensity index) phenophases. Unlike ferns from tropical regions that generally regulate themselves by the rainfall, some ferns in a non-seasonal environment have seasonal behavior in their phenophases due to the greater amplitude of photoperiod and temperature. The community showed the same pattern of leaf production observed in populations of other subtropical regions in the world. This behavior represented the biological response of the vegetation dynamics in relation to the climatic variability of subtropical environment. [ABSTRACT FROM AUTHOR]

Tropical plant assemblages can be taxonomically and phylogenetically impoverished by chronic anthropogenic disturbance (CAD), such as firewood collection and extensive grazing. However, to what extent the functional dimension responds to CAD is still unclear. Such knowledge is urgently required for predicting, preventing or even reversing the impacts of CAD.Chronic anthropogenic disturbance may operate as an ecological filter by selecting functional trait values (e.g. low wood density), thereby altering the functional composition and diversity of plant assemblages. We tested this hypothesis using 29 woody plant assemblages across three ontogenetic stages (seedlings, saplings and adults) in a 220‐km2 landscape of the Caatinga, northeast Brazil. We adopted a CAD index consisting of four indicators (proximity to urban centre and houses and the density of both people and livestock) and tested how well it explained the functional diversity and effect sizes (richness, evenness and dispersion) and composition (community‐weighted mean).Chronic anthropogenic disturbance affected several functional metrics across the three ontogenetic stages. However, CAD effects were stronger in adult communities by negatively affecting functional richness, dispersion and their effect sizes. CAD also altered the functional composition of leaf mass per area, woody density and leaf area of adult assemblages. Sapling communities were affected in terms of functional composition (leaf area, leaf dry matter and wood density), with positive and negative effects, while seedling assemblages responded positively to CAD only in terms of functional evenness and its effect size. Some changes in functional metrics were influenced by dominant Euphorbiaceae species across ontogenetic stages, especially in terms of leaf area and woody density.Synthesis. Chronic anthropogenic disturbance is an important driver of plant‐community functional organization across ontogenetic stages in the Caatinga. Adult assemblages are particularly sensitive and tend to lose functional niche space and support more acquisitive rather than conservative strategies as chronic anthropogenic disturbance increases. The proliferation of Euphorbiaceae disturbance‐adapted species can explain part of the community responses to chronic anthropogenic disturbance. Our findings highlight the ecological effects of chronic anthropogenic disturbance and show that it is a key influence on tropical biotas. Changes in plant functional traits associated with plant resource use are likely to affect ecosystem functioning and services provided by Caatinga. [ABSTRACT FROM AUTHOR]

In this work we explore the radiocarbon (14C) signal as an independent tool to assess the year of formation of individual tree rings of tropical species in northern Brazil. Three different species were analyzed in this work: Dipteryx magnifica, Enterolobium maximum, and Hymenolobium petraeum. The studied samples are from the stem of only one individual of each species, all cut down in 2008 in Porto Trombetas, Pará, Brazil. Individual tree rings were identified based on wood anatomy and they were counted from bark to pith. Several rings were selected for 14C analysis in order to cover the overall shape of the 14C atmospheric bomb peak (after 1955). The 14C content was measured at Laboratory of Radiocarbon, Universidade Federal Fluminense (LAC-UFF). Results are compared with the Southern Hemisphere 14C atmospheric calibration curves. For E. maximum and H. petraeum the 14C signal exhibits an overall good match with the SH zone 3 and suggests annual seasonality in the growth-ring formation. These species offer suitable characteristics for dendrochronology. The D. magnifica shows mismatches in the 14C measurements that are likely a result of difficulties in identifying ring boundaries with certainty. Additional techniques may be helpful to disentangle the origin of this discrepancy. [ABSTRACT FROM AUTHOR]

Questions We investigated the effects of grassland management intensity and temporary conversion to other land uses on abiotic and biotic properties of subtropical grasslands. We used species-rich permanent grasslands of medium management intensity ( PG-M) as a reference, and asked the following questions: (1) do permanent grasslands with low and high management intensities ( PG-L and PG-H, respectively) have different plant diversity and species composition than reference grasslands; and (2) do secondary grasslands recovering from conversion to arable fields ( SG-A) or pine plantations ( SG-P) differ from permanent grasslands in their plant species composition and abiotic conditions? Location Highland grasslands, Campos de Cima da Serra, Rio Grande do Sul ( RS), Brazil. Methods We analysed variation in plant species composition and diversity among 80 grassland sites, including three types of permanent grassland and two types of secondary grassland. An indicator species analysis was used to identify characteristic species for the different land-use types. We used a linear discriminant analysis to investigate differences in soil conditions among land-use types. Results Both PG-L and PG-H differed from PG-M regarding plant species composition. Although PG-L shared many typical grassland species with PG-M, their communities were generally less diverse. PG-H, on the other hand, not only had fewer species but also deviated from PG-M in species composition. Secondary grasslands on former arable fields and plantations differed from PG-M in species composition and showed lower diversity. Soil conditions of SG-P were similar to those of PG-L and PG-M, but they were distinct from those of PG-H and SG-A. Conclusions All land-use types showed deviations from reference grasslands ( PG-M). The decrease in the number of species in PG-L may be reversed if traditional management intensity is re-introduced, whereas strong compositional changes in SG-P may require the re-introduction of grassland species. This is also true for PG-H and SG-A: both showed marked deviations from reference grasslands in biotic and abiotic components. Overall, restoration of altered land-use types to near-natural subtropical grassland seems feasible, but suitable techniques have to be developed. [ABSTRACT FROM AUTHOR]

Seasonally Dry Tropical Plant Formations (SDTFs) are among the most threatened biomes worldwide. Nevertheless, they have received less scientific attention than rainforests or savannas. One such SDTF, the Caatinga Phytogeographic Domain (CPD), is the largest semiarid tropical ecoregion in South America. Earlier floristic studies of the Caatinga flora discerned two floristic groups in the CPD, in terrains of crystalline and sedimentary origin respectively. We compiled and analysed the most comprehensive dataset on CPD plant distributions to produce a general biogeographical synthesis for Caatinga, including inselbergs, riverine forests and ecotonal areas. Not only are crystalline and sedimentary caatingas clearly distinct, but inselbergs collectively form a third floristic group in the CPD. Non-woody plants, omitted from many studies, are a major component of Caatinga diversity, comprising more than 60 % of species in some local communities. Raunkiaerian life-form spectra of Caatinga sites show that Caatinga vegetation differs in life-form spectra from those of major world biomes, supporting recognition of SDTFs as a discrete world biome. [ABSTRACT FROM AUTHOR]

In hyper fragmented biomes, conservation of extant biota relies on preservation and proper management of remnants. The maintenance of genetic diversity and functional connectivity in a landscape context is probably key to long-term conservation of remnant populations. We measured the genetic diversity in seedlings and adults of tree Copaifera langsdorffii and evaluated whether edge and density-dependent effects drive natural regeneration in a set of very small and degraded Brazilian Atlantic forest fragments. We evaluated the role of small remnants in the conservation of genetic diversity in a hyper fragmented landscape and discuss the challenge of long-term population sustainability of such altered habitats. High genetic diversity in adults indicated these fragments are valuable targets for C. langsdorffii in situ conservation, but both genetic diversity and divergence among patches decreased in seedlings. In our landscape, regeneration increased as it neared edges and adults; suggesting this population is resilient to fragmentation. However, at a broader scale, current levels of gene flow have not been sufficient to prevent the loss of genetic diversity across generations. Restoration plans, even at a small scale, are necessary to promote fragment connectivity and spatially expand opportunities for the fairly restricted gene flow observed in this severely fragmented Brazilian Atlantic forest region. [ABSTRACT FROM AUTHOR]

Background:The identification of genetic divergence among provenances is essential for designing seed zones for ecological restoration, but this is neither easy nor cheap, especially where tropical trees are concerned. Aims:In this study we sought to investigate the effectiveness of common garden and short-term reciprocal transplant experiments to identify genetic divergence in populations of Queen palm (Syagrus romanzoffiana). Methods:Seed harvesting was carried out in south-eastern Brazil, in natural remnants of seasonally dry forest, restinga and cerradão. Under common garden conditions, we examined the length of the cotyledonary petiole of three-month-old seedlings, and important sapling traits of 10-month-old nursery-grown individuals of the three above-mentioned seed provenances. Additionally, reciprocal transplants were carried out during 10 months for seasonally dry forest and cerradão seed lots. Results:In the common garden experiments, restinga seedlings had significantly shorter cotyledonary petioles, and cerradão saplings showed ca. 40% higher values for root, leaf blade, shoot and total dry mass, while saplings did not express genetic differences in reciprocal transplants, which is one of the four possible combined outcomes discussed here. Conclusions:Common garden experiments with long-lived tropical plant species used in ecological restoration can be advantageously used to improve the quality of the seed sources for restoration projects by detecting genetic divergence with a possible relation to local adaptation. [ABSTRACT FROM AUTHOR]

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Highlights: [•] Integrated crop–livestock systems in the Brazilian subtropics are highly diverse. [•] Livestock reduce the vulnerability of crops in rain-fed systems. [•] Crops in rotation with livestock may produce more. [•] Livestock improve many physical, chemical and biological attributes of soil. [•] Integrating crops and livestock is a unique approach to ecological intensification. [ABSTRACT FROM AUTHOR]

Highlights: [•] N2O flux was higher in integrated crop-livestock than in continuous crop. [•] N application was the main cause of higher N2O emission in crop-livestock. [•] Fluxes of CH4 were not affected by soil management systems. [•] No soil organic carbon sequestration occurred in crop-livestock to offset N2O emission. [Copyright &y& Elsevier]

Precision agriculture relies on site-specific interventions determined by the spatial variability of factors driving plant growth. The main objective of this study was to assess the efficiency of variable-rate seeding of corn ( Zea mays L.) with delineated management zones. This study involved two experiments carried out in Não-Me-Toque, Rio Grande do Sul, Brazil. For the first experiment, carried out in 2009/2010, management zones were delineated by the farmer's knowledge of the crop field. The field was split into low (LZ), medium (MZ) and high (HZ) crop performance zones. In the second experiment, carried out in 2010/2011, management zones were delineated by overlaying standardized yield data from nine crop seasons (seven of soybean and two of corn). The experiment was carried out with a randomized block design with three management zones and five corn seeding rates ranging from 50 000 to 90 000 seeds per ha. The soil was a Rhodic Hapludox with a subtropical climate. Optimization of the corn plant population within the field increased grain yield compared to the reference plant population (70 000 plants ha). Yield increases in the LZ, due to corn plant population reduction in relation to the target population, were 1.20 and 1.90 Mg ha for first and second experiments, respectively. This resulted in economic gains of 19.8 and 28.7 %, respectively. Yield increases in the HZ were 0.89 and 0.94 Mg ha, respectively, and were due to an increase in plant population in relation to the target population. This resulted in economic gains of 5.6 and 6.6 % for the first and second experiments, respectively. In the MZ, the adjustment of the target plant population was not necessary. Optimizing corn population according to management zones is a promising tool for precision agriculture in Southern Brazil. [ABSTRACT FROM AUTHOR]

Highlights: [•] We evaluate adaptability and stability for leafing of peach genotypes in a subtropical climate. [•] A high percentage of budburst does not necessarily lead to a high percentage of fruiting shoots formed. [ • ] We signalized the genotypes that had good percentages of budburst and fruiting shoots, remained stable for both traits during all evaluated years, and were considered well adapted for subtropical climate conditions. [ABSTRACT FROM AUTHOR]

Abstract: The assessment of damage to indoor cultural heritage, in particular by pollutants, is nowadays a major and growing concern for curators and conservators. Nevertheless, although many museums have been widely investigated in Europe, the effects of particulate matter and gaseous pollutants in museums under tropical and subtropical climates and with different economic realities are still unclear. An important portion of the world's cultural heritage is currently in tropical countries where both human and financial resources for preserving museum collections are limited. Hence, our aim is to assess the damage that can be caused to the artwork by pollution in hot and humid environments, where air quality and microclimatic condition differences can cause deterioration. As a case study, particulate matter as well as gases were collected at the Oscar Niemeyer Museum (MON) in Curitiba, Brazil, where large modern and contemporary works of art are displayed. NO2, SO2, O3, Acetic Acid, Formic Acids and BTEX, in the ambient air, were sampled by means of passive diffusive sampling and their concentrations were determined by IC or GC–MS. The particulate matter was collected in bulk form and analyzed with the use of energy dispersive X-ray fluorescence and aethalometer. The chemical compositions of individual particles were quantitatively elucidated, including low-Z components like C, N and O, as well as higher-Z elements, using automated electron probe microanalysis. The gaseous and particulate matter levels were then compared with the concentrations obtained for the same pollutants in other museums, located in places with different climates, and with some reference values provided by international cultural heritage conservation centers. Results are interpreted separately and as a whole with the specific aim of identifying compounds that could contribute to the chemical reactions taking place on the surfaces of artifacts and which could potentially cause irreversible damage to the artworks. [Copyright &y& Elsevier]

A high level of endemic flowering plant species is highlighted for the first time for the southern Brazilian flora. We present a comprehensive list of 1020 endemic taxa and analyse their distribution in different biomes, focusing on the Subtropical Highland Grasslands (Campos de Cima da Serra). Considering all biomes represented in southern Brazil, c. 13% of the flowering plant species are endemic, which accounts for more than 5% of the total endemic taxa of Brazil and c. 12% of the endemic taxa from the Atlantic Forest hotspot. Like the High Altitude Tropical Grasslands that are found further north in the south-eastern Brazil region, the Subtropical Highland Grasslands are home to an assemblage of tropical and temperate plant lineages. The Subtropical Highland Grasslands are characterized by their transitional nature and by having 296 endemic plant taxa (25% of its flora). © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, 167, 378-393. [ABSTRACT FROM AUTHOR]

Abstract: The influence of water potential (Ψ W) on the leaf phenological behaviors of five arboreal species within gallery and montane forests on the eastern slope of the Chapada Diamantina Mountain Range in Bahia State, NE Brazil, was examined to investigate the following questions: (1) Do seasonal variations in rainfall influence the water potential of these species in their natural habitats (gallery and montane forests)? (2) Do the gallery forest species show smaller daily variations in their water potential and greater nocturnal recuperation than montane species? (3) Can the water potentials of these species be used to identify their particular types of leaf phenologies? The species examined were Tibouchina fissinervia and Clusia nemorosa (evergreen with continual leafdrop); Tapirira guianensis and Vochysia pyramidalis (evergreen with concentrated leafdrop), and Maprounea guianensis (brevi-deciduous) were chosen based on their abundance, importance value indices, and contrasting phenological behaviors. The leaf phenologies of all species were similar in both forest types. Evergreen species with continual leafdrop demonstrated leaf budding and leaf fall occurred at low levels during the entire year. Evergreen species with continual leafdrop as well as brevi-deciduous species demonstrated peaks of leaf fall and leaf budding during the dry period. Brevi-deciduous trees remained without leaves for an average of three days. The major episodes of leaf budding occurred during the dry period in all of the species examined. M. guianensis usually demonstrated low predawn (Ψ PD) and midday (Ψ MD) water potentials (Ψ W). C. nemorosa demonstrated the greatest Ψ PD and Ψ MD values and the lowest daily amplitude (Δ Ψ ), suggesting that this plant used CAM during most of the study period. The majority of the species demonstrated small seasonal differences in Ψ W, and the Ψ PD values indicated a satisfactory nocturnal recuperation of their water status, even during the dry period. The maximum daily amplitude of Ψ W was observed in V. pyramidalis, a species dependent on moist habitats for establishment and growth. No large decrease in Ψ PD was observed during the study period in the species examined here, and all species demonstrated leaf budding during the dry period, suggesting that there were no severe water restrictions in either the gallery or montane forests. However, during dry periods, the species generally demonstrated lower Δ Ψ . This reflects the restriction of transpiration, which according to phenological data, may occur due to different mechanisms, depending on the species. Our data supports the view that there is no strict relationship between decreasing water status in these plants and leaf fall. [Copyright &y& Elsevier]

obtaining parameters to assess growth and the potential production of Pinus, the present work aims to adjust traditional models of hypsometric relation to species Pinus caribaea Morrelet var. hondurensis Barret & Golfari and Pinus tecunumanii Eguiluz & Perry, in pure stand, in the municipality of Vilhena, Rondônia State. Ten modal analysis of the residues. The model d/√h = βels were adjusted and the selection criteria followed the lower standard error of estimate (Syx%), higher adjusted coefficient of determination (R2aj.), F value and regression coefficients significant and graphic0 + β1.d + ϵi showed the better fit, with R2aj. of 0,896 and Syx% of 3,941% for P. caribaea var. hondurensis and R2aj. of 0,973 and Syx% of 6,319% for P. tecunumanii. [ABSTRACT FROM AUTHOR]

Abstract: Despite the increasing number of studies on lianas, few of them have focused on liana and host-tree (phorophyte) interactions from a network perspective. Most studies found some network structure in other systems, such as plant facilitation and host-epiphyte. However, a recent study found no structure in a small network of liana–phorophyte interactions. Our aim was to investigate the hypothesis that rich, highly diverse systems yield large interaction networks with some structure. If so, networks of liana–phorophyte interactions in highly diverse systems will have one or more of the following structures: compartmentalized, nested or compound. We sampled three highly diverse vegetation formations: a tropical rainforest, a tropical seasonally dry forest, and a woodland savanna, all in southeastern Brazil. We used simulated annealing to test compartmentalization and found no compartment in any of the three networks analyzed. By means of a modified classical temperature index, we found a nested structure in all three sites sampled. We inferred that these nested structures might result from phorophyte characteristics and sequential colonization by different liana species and might promote increased diversity in tropical tree formations. We propose that, according to the system complexity and the different variables associated with site and liana–phorophyte characteristics, a network may have a structure, which arises in more complex systems. Since we have investigated highly diverse systems with large networks, nestedness could be clearly detected in our study. [Copyright &y& Elsevier]

Papaya (Carica papaya) is an important tropical fruit crop in northeastern Brazil. Lethal yellowing is a disease caused by Papaya lethal yellowing virus (PLYV) that occurs only in northeastern Brazil. The symptoms are characterized by progressive leaf yellowing and greenish circular spots on the fruits. The virus has isometric particles (30 nm), genomic single-stranded (ss)RNA (1.6 × 106 Da), and a coat protein with a single component (35 kDa). Although no biological vector has been confirmed, the virus is spreading every year. In the present study, an isolate of the virus was characterized biologically, serologically, physically, and molecularly, and its survival in dried tissue was evaluated. Approximately 309.5 mg of virus was purified per kilogram of infected papaya leaves, and a high-titer polyclonal antiserum (1:1,024,000) was obtained from an immunized rabbit. The virus was detected in dried roots and leaves maintained up to 120 days. Its physical properties were thermal inactivation point (80°C), longevity in vitro (60 days), and dilution end point (10-6). The virus was inactivated in leaves and roots eradicated from infected plants when they were submitted to a solarization period of 12 days, but maintained its infectivity when leaves and roots were maintained over the soil at natural conditions for 32 days. Among 58 plant species from 13 botanical families, the PLYV isolate infected only C. papaya, Jacaratia heterophylla, J. spinosa, Vasconcella cauliflora, V quercifolia, and V. monoica, all from the family Caricaceae. A fragment of 1,098 nt of the virus isolate, corresponding to the 3′ replicase (RdRp) and 5′ coat protein (CP) cistron, was cloned and sequenced. Phylogenetic analysis of the RdRp nucleotide sequences indicated some similarity of PLYV with members of the genus Sobemovirus. [ABSTRACT FROM AUTHOR]

Copyright of Revista Brasileira de Biociencias is the property of Revista Brasileira de Biociencias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The objective of this study was to evaluate the diversity of Phytoseiidae in the Atlantic Forest of Sao Paulo State, Brazil, and to estimate the possible role of this ecosystem as a reservoir for mites of this family. Samples were taken from 187 plant species belonging to 73 plant families in three vegetation types of the Atlantic Forest, from February 2001 to October 2002. In total, 1102 specimens of 54 species belonging to 20 genera of the three phytoseiid subfamilies were found. Most specimens (93%) and species (91%) belonged to the Amblyseiinae. The majority of species found belong to taxonomic groups largely composed of generalist predators (especially Amblyseius and Euseius). In general, the more abundant mites were found on a diversity of plant species, but a few of the abundant species were found on only a small number of plant species. Only nine of the mites encountered during this study are of known agricultural importance. The results obtained suggest the importance of the wide plant diversity in the region to sustain a wide diversity of phytoseiids. The extensive clearance of the Brazilian Atlantic Forest is a threat to the diversity of these mites, important predators of mite pests. [ABSTRACT FROM AUTHOR]

Abstract: We examined the potential growth of clonal Eucalyptus plantations at eight locations across a 1000+ km gradient in Brazil by manipulating the supplies of nutrients and water, and altering the uniformity of tree sizes within plots. With no fertilization or irrigation, mean annual increments of stem wood were about 28% lower (16.2Mgha−1 yr−1, about 33m3 ha−1 yr−1) than yields achieved with current operational rates of fertilization (22.6Mgha−1 yr−1, about 46m3 ha−1 yr−1). Fertilization beyond current operational rates did not increase growth, whereas irrigation raised growth by about 30% (to 30.6Mgha−1 yr−1, about 62m3 ha−1 yr−1). The potential biological productivity (current annual increment) of the plantations was about one-third greater than these values, if based only on the period after achieving full canopies. The biological potential productivity was even greater if based only on the full-canopy period during the wet season, indicating that the maximum biological productivity across the sites (with irrigation, during the wet season) would be about 42Mgha−1 yr−1 (83m3 ha−1 yr−1). Stands with uniform structure (trees in plots planted in a single day) showed 13% greater growth than stands with higher heterogeneity of tree sizes (owing to a staggered planting time of up to 80 days). Higher water supply increased growth and also delayed by about 1 year the point where current annual increment and mean annual increment intersected, indicating opportunities for lengthening rotations for more productive treatments as well as the influence of year-to-year climate variations on optimal rotations periods. The growth response to treatments after canopy closure (mid-rotation) related well with full-rotation responses, offering an early opportunity for estimating whole-rotation yields. These results underscore the importance of resource supply, the efficiency of resource use, and stand uniformity in setting the bounds for productivity, and provide a baseline for evaluating the productivity achieved in operational plantations. The BEPP Project showed that water supply is the key resource determining levels of plantation productivity in Brazil. Future collaboration between scientists working on silviculture and genetics should lead to new insights on the mechanisms connecting water and growth, leading to improved matching of sites, clones, and silviculture. [Copyright &y& Elsevier]

Copyright of Revista Brasileira de Biociencias is the property of Revista Brasileira de Biociencias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: Considering the pressures on tropical forests from deforestation and the recent expansion of harvesting through forest concessions in the Brazilian Amazon, it is imperative that forest management systems are scrutinized to ensure sustainability. One of the basic problems in forest management is the correct identification of species within the forest stand. While this is a well known issue, little consideration is given to how to mitigate this problem or its affects on management practices and conservation. This paper examines the current practice of forest inventories in the Brazilian Amazon, as part of the mandatory system of reduced impact logging (RIL), using extensive forest inventory verification. The results show that the RIL management plan implemented in the project area was based on a highly inaccurate forest inventory. At least 132 species or 43.5% of all species identified after botanical checking did not appear in the forest inventory and the common practice of matching vernacular names to scientific ones proved to be severely deficient. In contrast, a high percentage of field identifications based on local people''s expertise were correct. We suggest changes to current practices, including the training and use of parataxonomists, the collection of samples for verification, and stricter government control over current practices, which will achieve greater accuracy in data collection and forest management planning. Ultimately, we argue that in the current climate of extensive deforestation and forest use, it is essential that all aspects of RIL systems are reevaluated in order to achieve economic and ecological sustainability. [Copyright &y& Elsevier]

Abstract: We present a model describing phytoplankton growth in Lake Mangueira, a large subtropical lake in the Taim Hydrological System in South Brazil (817km2, average depth 2m). The horizontal 2D model consists of three modules: (a) a detailed hydrodynamic module for shallow water, which deals with wind-driven quantitative flows and water level, (b) a nutrient module, which deals with nutrient transport mechanisms and some conversion processes and (c) a biological module, which describes phytoplankton growth in a simple way. We solved the partial differential equations numerically by applying an efficient semi-implicit finite differences method to a regular grid. Hydrodynamic parameters were calibrated to continuous measurements of the water level at two different locations of the lake. An independent validation data set showed a good fit of the hydrodynamic module (R 2 ≥0.92). The nutrient and biological modules were parameterized using literature data and verified by comparing simulated phytoplankton patterns with remote sensing data from satellite images and field data of chlorophyll a. Moreover, a sensitivity analyses showed which parameters had the largest influence on the simulated phytoplankton biomass. The model could identify zones with a higher potential for eutrophication. It has shown to be a first step towards a management tool for prediction of the trophic state in subtropical lakes, estuaries and reservoirs. [Copyright &y& Elsevier]

The objective of this research was to assess the degradation of fipronil [5-amino-1-(2,6-dichloro-α,α,α -trifluoro-p-tolyl)-4-trifluoromethylsulfinylpyrazole-3-carbonitrile] in soils from sugar cane fields in Northeastern Brazil. Degradation experiments were carried out under laboratory conditions (controlled temperature and in the dark), where sterile and non-sterile soils (Ustoxs) were incubated [under moisture content of 55% of the water holding capacity (WHC)] and analyzed for fipronil disappearance and metabolite formation. Microbial communities present in the soil degrade fipronil. However, biodegradation seems to be dependent on the bioavailability of the fipronil and the half-life according to the zero-order model. Fipronil degradation rate appeared to be biphasic. Degradation fipronil ranged from 83 days (initial concentration = 978 ng g- 1; short-term experiment) to 200 days (initial concentration = 689 ng g- 1; long-term experiment). This an initial slower rate followed by a faster rate after 90 days of incubation may lead to shorter half-life than that calculated with the zero-order model. The sulfone derivative (an oxidation product) was the predominant metabolite, but the sulfide (a reduction product) and amide (a hydrolysis product) derivatives were also formed under non-sterile conditions after 120 days of incubation. The metabolites underwent further biodegradation, particularly the sulfone derivative. Bioavailability appears to affect fipronil degradation in soils with an effective capacity to adsorb fipronil (such as Ustoxs), while redox potential was important for the formation of metabolites. Despite the fine texture, more aerobic sites were present, thus favoring the formation of the sulfone metabolite over that of the sulfide metabolite. Therefore, microaggregation of Ustoxs, with high clay content, played a very important role in determining the types of metabolites formed. [ABSTRACT FROM AUTHOR]

Question: How does fire influence species richness and diversity in subtropical grassland in southern Brazil? Location: Recurrently burned grassland in Porto Alegre, Brazil (30003 S, 51°07' W; max. altitude 311 m a.s.l.) and abandoned grassland near Säo Francisco de Paula, Brazil (29°47 S, 50°22 W; ca. 900 m a.s.l.). Methods: In the burned grassland, between-year changes in community composition and single-plot diversity, species number and vegetation structure were analysed in two consecutive years for plots with different time since last fire. Responses to fire of individual species were analysed. At the abandoned site, diversity, species number and vegetation structure were examined. Results: Species number and small-scale species turnover were highest ca. one year after the burn, and decreased as caespitose grasses increased in cover with time since fire until reaching a stable, but less diverse state three to four years after a fire. The abandoned grassland showed higher dominance of caespitose grasses and lower richness and diversity. Conclusions: Fire clearly leads to a short-term increase in species richness and diversity at the plot scale, as competitive interactions are being reduced and recruitment possibilities are high in early post-fire vegetation development. Overall community composition does not change after a fire. While small herbs seem to be slightly favoured in the early post-fire environment, no clear group of fire following species (absent in vegetation unburned for longer) was observed. The results indicate that the community is adapted to the current fire regime and is being maintained under the influence of fire. [ABSTRACT FROM AUTHOR]

The article presents a study that describes the abundance of liana and species composition in gaps created during conventional and reduced-impact logging in a forest in eastern Brazil. It describes the method of the study that conducts logging treatments in side-by-side plots. It outlines the result which shows that pre-logging liana cutting can reduce post-logging proliferation in gaps with no negative effects on the species' diversity.

Presents an empirical cohort model for management of Terra Firme forests in the Brazilian Amazon. Basis of the model; Aim of the model.

• Egeria najas and Hydrilla verticillata (invasive) co-occur in the Itaipu Reservoir. • Abundance variation drivers were analyzed with a spatio-temporal Bayesian modelling. • E. najas and H. verticillata relate negatively with water level oscillations. • Correlations between E. najas and H. verticillata depend on relative abundance. • Previous species abundance is an important determinant of current abundance. The invasion success of non-native species depends on a variety of factors, and abiotic characteristics of invasive ranges and their native populations can offer resistance to non-native species establishment. Reservoirs, compared to natural lakes, can facilitate submerged macrophyte invasion because they provide favorable abiotic conditions to macrophyte establishment and development. However, previous colonization of native species can hamper the development of invasive ones through priority effects. In this investigation we used large data-set obtained in the Itaipu Reservoir (Brazil/Paraguay) to assess the relationship between the abundance of the native submerged macrophyte Egeria najas and of the invasive Hydrilla verticillata and water level, littoral slope and Secchi disk depth. We also investigated how the concomitant and previous abundance of both macrophytes correlates. A Bayesian modeling was applied, controlling the effect of spatial-temporal autocorrelation. Our results indicate an important role of water transparency, littoral slope and water level oscillations in a short period of time (30 days) for the temporal dynamics of these species' abundances. Fluctuations of water levels and littoral slope affected H. verticillata to a greater extent than E. najas. In addition, the abundance of each species was related with its own abundance in previous samplings, highlighting the possible importance of habitat suitability, vegetative propagule pressure and resistance structures for population recovery. In low abundances, there was a possible facilitation between both species, while high abundances probably increased competition. The great importance of water level oscillations on these species' abundances indicate that this strategy can be used as management tool. [ABSTRACT FROM AUTHOR]

In this work we critically assess the soil-to-plant transfer factors (TF) for 137Cs and 40K in edible fleshy organs of tropical plants that are often components of the human diet. Radionuclide concentrations in soil and plants were obtained from previous investigations developed in Brazil, after the Goiânia radiological accident occurred in 1987. Transfer factors were determined in specific plant compartments (main root, main stem, bark, old and new branches, twig, old and new leaves, mature and green edible organs) of tropical species such as lemon (Citrus aurantifolia), orange (Citrus sinensis), guava (Psidium guajava), chili pepper (Capsicum frutescens), pomegranate (Punica granatum), papaya (Carica papaya), banana (Musa paradisíaca), and manioc (Manihot esculenta). For 137Cs, soil-to-fruit transfer factor ranged from 0.80 × 10−2 (banana) to 3.65 × 10−1 (pomegranate); for 40K, this factor was from 4.42 × 10−1 (orange) to 1.74 (chili pepper). Considering all the plant compartments analysed, the transfer factors for 40K are between 24.5 (guava) and 90.5 (papaya) times higher than for 137Cs. For both radionuclides, considerable differences in soil-to-plant transfer were found when new growing parts of the plant (green edible organ, leaf, and twig) are considered with respect to those older parts (mature edible organ, old leaf and branches). Considering all the species analyzed, the relationship TF (40K)/ TF (137Cs) does not seem to follow a characteristic pattern. However, if we compare the value of this relationship for two organs of the same plant, the result is approximately constant, regardless of the species considered. This confirms earlier evidence that both radionuclides are similarly distributed in the different organs of the studied species. The differences in the transfer factors according to the ripening status of edible organs must be particularly considered when estimating the dose from ingestion of fruits and their derivatives in dose assessment models. • 137Cs and 40K soil-to-plant transfer factors are assessed in plants growing in a tropical environment. • TF for both radionuclides exhibit considerable dependence on plant species. • For most species TF values result higher in green fruits compared to the mature ones. • 137Cs and 40K are similarly distributed in the different organs of the examined species. [ABSTRACT FROM AUTHOR]

Herbivory is ubiquitous. Despite being a potential driver of plant distribution and performance, herbivory remains largely undocumented. Some early attempts have been made to review, globally, how much leaf area is removed through insect feeding. Kozlov et al., in one of the most comprehensive reviews regarding global patterns of herbivory, have compiled published studies regarding foliar removal and sampled data on global herbivory levels using a standardized protocol. However, in the review by Kozlov et al., only 15 sampling sites, comprising 33 plant species, were evaluated in tropical areas around the globe. In Brazil, which ranks first in terms of plant biodiversity, with a total of 46,097 species, almost half (43%) being endemic, a single data point was sampled, covering only two plant species. In an attempt to increase knowledge regarding herbivory in tropical plant species and to provide the raw data needed to test general hypotheses related to plant–herbivore interactions across large spatial scales, we proposed a joint, collaborative network to evaluate tropical herbivory. This network allowed us to update and expand the data on insect herbivory in tropical and temperate plant species. Our data set, collected with a standardized protocol, covers 45 sampling sites from nine countries and includes leaf herbivory measurements of 57,239 leaves from 209 species of vascular plants belonging to 65 families from tropical and temperate regions. They expand previous data sets by including a total of 32 sampling sites from tropical areas around the globe, comprising 152 species, 146 of them being sampled in Brazil. For temperate areas, it includes 13 sampling sites, comprising 59 species. Thus, when compared to the most recent comprehensive review of insect herbivory (Kozlov et al.), our data set has increased the base of available data for the tropical plants more than 460% (from 33 to 152 species) and the Brazilian sampling was increased 7,300% (from 2 to 146 species). Data on precise levels of herbivory are presented for more than 57,000 leaves worldwide. There are no copyright restrictions. Please cite this paper when using the current data in publications; the authors request to be informed how the data is used in the publications. [ABSTRACT FROM AUTHOR]

• Do functional traits explain plant community organization in a short edaphic gradient? • Four plant communities were influenced by organic matter, sodium and moisture. • Trees/shrubs showed a conservative strategy investing in permanent aerial organs. • Herbs invested in root reserves showing different ecological strategies along the gradient. • Anatomical traits were important to differentiate subtropical coastal plant communities. The relationship between plant functional traits and soil variables is useful for understanding plant community composition and circumscribing plant functional groups to highlight their adaptations to environmental conditions. The principal aim of this study was to explain assembly patterns of coastal vegetation using functional traits along a short edaphic gradient. The work was carried out on the pioneer zone in the coastal lowland vegetation (foredune) in southern Brazil. We selected 40 functional traits related to the morphology and anatomy of leaves, stems and roots for 60 species recorded in 25 vegetation plots positioned along three transects from the shoreline to slacks. In each plot, floristic and soil data were collected, and functional traits measured. We analysed the relationships between species functional traits and soil factors through RLQ and fourth-corner analyses. Salinity and organic matter content were the most significant edaphic factors in the differentiation of foredune vegetation, while the most significant traits to explain plant adaptations to coastal environments were plant height, sclerenchyma, spongy parenchyma and reserves of inulin in the root. Two functional groups of plants were circumscribed: a conservative group formed by trees and shrubs dominated the Woody Community, with low values of SLA (specific leaf area), thick cuticles, high frequencies of phenolic compounds and crystals, woody stems and great plant heights, which tended to invest in permanent aerial organs; and a more heterogeneous group of herbaceous plants (found in Beach Community, Non-floodable, and Wet Communities) with acquisitive characteristics (high SLA values) or conservative strategy (rhizome and xylopodium). Finally, our results suggested that root and stem functional traits, which are infrequently taken into consideration, were useful to differentiate subtropical coastal plants and, in general, to study plant adaptations to environmental conditions in depth. [ABSTRACT FROM AUTHOR]

• We generated equations to predict PUE and allocation in eucalypt stands. • The functions include stand age, area per tree, clay content and annual rainfall. • Validation shows the equations are suitable for predicting both PUE and P allocation. Low phosphorus availability is a key constraint for plant growth in tropical soils. Unlike most cultivated crops, recommendations of phosphates and other fertilizers for part of the commercial eucalypt stands in Brazil are based on nutrient budget modelling. Nutrient use efficiency and allocation between plant tissues are important variables in these models. Here, we use data from previous studies to generate a set of equations to predict phosphorus use efficiency (PUE) and allocation (PA) within eucalypt stands. Specifically, we fitted sigmoidal models with commonly data available for climate and stand characteristics as predictors of PUE and PA. Our PUE estimates were also used to estimate the aboveground phosphorus content (APC) in the stands. Using an 80/20 data split for parameterization and evaluation, we found that our functions were suitable for predicting PUE, PA and APC. The equations presented here may be used to estimate nutrient needs and exports in even-aged eucalypt stands and to facilitate parametrization of empirical and mechanistic models. [ABSTRACT FROM AUTHOR]

• Restoration plantings complement plant diversity of fragments at large scale. • Fragments are diversity repositories that should be considered in restoration plans. • Fragments and restoration plantings act synergistically to recover plant diversity. Ecological restoration can re-establish plant species populations, enhance forested habitats extension, improve landscape connectivity, and enable biodiversity persistence within a landscape. However, the potential benefits of ecological restoration on beta diversity have never been explored. Here we use field data to investigate, for the first time, if restoration plantings enhance the taxonomic and functional plant beta diversity in a fragmented landscape of the threatened Atlantic forest. Woody species were evaluated for 320 plots established in 18 forest fragments and 14 restoration plantings within a sugarcane production landscape with low forest cover, in southeastern Brazil. Diversity metrics were assessed using the multiple incidence-data version of Hill numbers and were compared among three sets of study sites: fragments, restoration plantings and the two combined. Fragments showed higher levels of alpha diversity and proportional abundance of non-pioneer and animal-dispersed species than restoration plantings. Exotic, pioneer and non-zoochoric species were more abundant in restoration plantings, an expected result considering sites still be in the early or mid-successional stages of development. Taxonomic and functional beta diversity of trees was greatest when both areas were combined. For regenerating plants, however, beta diversity results varied according to species incidence-based frequencies. Although restoration plantings do not result in full recovery of alpha diversity, they can all together complement diversity of forest fragments at the landscape level. The findings indicate two key ecological implications for biodiversity conservation: the critical importance of forest fragments as biodiversity repositories and the positive effect of restoration efforts on landscape-scale diversity in degraded regions. These novel results highlight the importance of species selection for restoration initiatives toward species and functional attributes recognized as significantly reduced or locally rare. Overall, forest fragments and restoration plantings can act synergistically to promote recovery of plant diversity in heavily deforested agricultural landscapes. [ABSTRACT FROM AUTHOR]