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Biodiversity in the Brazilian Cerrado biome has been declining sharply with the continued expansion of agriculture and the excessive use of herbicides. Thus, the aim of this study was to evaluate the morphophysiological and biochemical responses in

The Brazilian Atlantic Forest has been affected by the deposition of Ni and Zn, among other heavy metals adsorbed on atmospheric particles, which can be incorporated into the soil. If available in the soil, they can be absorbed by plant roots. The study aimed at testing experimentally the hypotheses: 1) Ni and Zn depositions increase their bioavailable fractions in the soil; 2) pioneer tree species absorb Ni and Zn from the soil in higher level and less growth changes than non-pioneer species. The experiment was carried out with six pioneer and non-pioneer species native to the Atlantic Forest, grown for 90 days in: soil with balanced fertilization (control) and in soil enriched with Ni, Zn or Ni + Zn. At the end, the concentrations of Ni and Zn were determined in four soil fractions (F1: soluble; F2: linked to oxides/hydroxides; F3: linked to organic matter: F4: residual metals) and in leaves, stems/branches and roots. Mobility factors in soil, concentration ratios between treatments and respective controls, translocation efficiency and relative growth rate in height, leaf number and total biomass were also calculated. The results showed that Ni and Zn concentrations increased significantly in the bioavailable soil fractions (F1, F2). The absolute content of Ni and Zn in the plants directly reflected the soil level in the available forms. Pioneer tree species absorb Ni and Zn in higher level and show less changes in growth than non-pioneer tree species.

Increased N deposition may cause nutritional imbalances in tropical ecosystems, by shifting N:P stoichiometry (as they are typically P-limited) and NH4-N:NO3-N ratios throughout their compartments. Based on this assumption, we aimed at verifying if the anthropogenic N deposition are inducing nutritional imbalances in trees, litter and soil in the remaining Atlantic Forest in SE Brazil. Three forest remnants were selected, one of them supposedly exposed to lower levels anthropogenic N deposition (peri-urban forest) than the other two (urban and agricultural-urban forests). We measured NO2 concentrations, wet and dry deposition of NH4-N, NO3-N and PO4-P and determined total/soluble N and P contents in samples of pioneer and non-pioneer trees, litter and soil. NH4-N:NO3-N and N:P ratios were calculated in all compartments. Multivariate analysis indicated associations between NH4-N, PO4-P and NH4:NO3 ratios in atmospheric deposition or NO2 concentrations and N and P contents in trees, litter and soil of all forest remnants. The comparison of N:P ratios in tree species and litter with those from studies conducted in the 1980–2000 indicated a tendency of N enrichment and increasing P scarcity in the Atlantic Forest remnants studied. Confirming the hypothesis, anthropogenic N deposition increases nutritional imbalances in the ecosystem compartments of forest remnants studied. The peri-urban forest showed to be more vulnerable to nutritional imbalances than the other forests, based on the comparisons with data from 30 to 40 years ago.

Chloroplasts have luminescent metabolites—chlorophyll being the most known one—whose fluorescence emission may be a useful tool to assess the physiological status of the plant. Some antioxidants (flavonoids and carotenoids), and byproducts of membrane rupture (lipofuscins) and chlorophyll degradation (pheophytins), are chloroplasts’ fluorescent metabolites directly involved in plant response to environmental stressors and pollutants and may act as a biomarker of stress. Here we hypothesized that climatic variations and air pollutants induce alterations in the emission profile of chloroplasts’ fluorescent metabolites in Tillandsia usneoides (Bromeliaceae). To test this hypothesis, an active biomonitoring study was performed during 2 years in five polluted sites located at the Metropolitan Region of Campinas (Sao Paulo State, Brazil), aiming to identify target chloroplasts’ fluorescent metabolites acting as biomarkers of environmental stress. In situ identification and quantification of the intensity of the fluorescence emission from target metabolites (flavonoids, carotenoids, lipofuscins, and pheophytins) were performed by the observation of fresh leaf sections under confocal laser scanning microscopy. Changes in the profile of fluorescence emission were correlated with local climate and air pollution data. The fluorescence emissions of flavonoids and carotenoids varied seasonally, with significant influence of rainfall and NO2. Our results expand the use of T. usneoides as a bioindicator by using alterations in the fluorescence emission profile of chloroplast metabolites. This application may be especially interesting for NO2 biomonitoring.

This study brings information on the dynamics of C and N in urban forests in a subtropical region. We tested the hypothesis that C and N isotopic sign of leaves and soil and physiological traits of trees would vary from center to periphery in a megacity, considering land uses, intensity of automotive fleet and microclimatic conditions. 800 trees from four fragments were randomly chosen. Soil samples were collected at every 10 cm in trenches up to 1 m depth to analyze C and N contents. Both, plants and soil were assessed for δ

Although the Brazilian Atlantic Forest is a hotspot for biodiversity conservation, it is one of the most fragmented biomes in Brazil and also affected by air pollutants such as polycyclic aromatic hydrocarbons (PAHs). The study aimed at measuring the PAH levels in leaf trees, litter, soil, and atmosphere of two Atlantic Forest remnants impacted by air pollutants during summer and winter periods; identifying emission sources; and investigating the relationship among the PAH concentrations in the soil, litter, leaves, and atmosphere. Site 1 is situated in the largest South American city, with rainy summers and dry winters, and characterized by intense urbanization. Site 2 is situated in a large forest continuum and is characterized by wet climate with no defined dry seasons. It is more distant from the anthropogenic urban sources than site 1, but closer to an industrial complex. No differences were detected for PAH amounts (summer + winter) in the particles and wet deposition fluxes between sites. In site 1, the highest concentrations of PAHs in the particles were measured during the winter while in the leaf trees were measured during the summer. PMF model showed that sites 1 and 2 receive PAHs mainly from vehicle emissions and industrial activities, respectively. The accumulation of heavier compounds in soil and leaves via wet deposition was more evident in site 2. PAHs were mainly stored in the soil of site 1, contrasting with site 2, where they were retained in litter, which were attributed to disturbances of decomposer community and reduced decomposition rates.

Fluoride (F) is one of the main environmental pollutants, and high concentrations are commonly detected in the air and in both surface and groundwater. However, the effects of this pollutant on seed germination and on the initial growth of crop seedlings are still poorly understood. In this context, the aim of this study was to assess morphoanatomical, physiological and biochemical fluoride effect indicators inThe germination parameters, and anatomical, morphological, physiological, biochemical and nutritional characteristics of the seedlings did not show negative effects from exposure to KF at the lowest doses evaluated. On the other hand, treatment with the highest dose of KF (30 mg LOur findings demonstrated that

© 2014 Psychonomic Society Inc. Although many facial and vocal databases are available for research very few of them have controlled the range of attractiveness of the stimuli that they offer. To fill this gap we created the GEneva Faces and Voices (GEFAV) database providing standardized faces (static and dynamic neutral smiling) and voices (speaking sentences vowels) of young European adults. A total of 61 women and 50 men 18–35 years old agreed to be part of the GEFAV stimuli and two rating studies involving 285 participants provided evaluations of the facial and vocal samples. The final set of stimuli was satisfactory in terms of attractiveness range (wide and rather symmetrical distribution over the attractiveness continuum) and the reliability of the ratings (high consistency between the two rating studies high interrater agreement in the final rating study). Moreover the database showed an adequate validity since a series of findings described by earlier research on human attractiveness were confirmed—namely that facial and vocal attractiveness are predicted by femininity and health in women and by masculinity dominance and trustworthiness in men. In future studies the GEFAV stimuli may be used intact or transformed individually or in multimodal combinations to investigate a wide range of mechanisms such as the behavioral neuropsychological and neurophysiological processes involved in social cognition.

Air pollution has been identified as a major cause of environmental and human health damage. O3 is an oxidative pollutant that causes leaf symptoms in sensitive plants. This study aims to adjust a multilinear model for the monitoring of O3 in subtropical climatic conditions by associating O3 concentrations with measurements of morphological leaf traits in tobacco plants and different environmental variables. The plants were distributed into five areas (residential, urban or industrial) in the southern region of Brazil and exposed during 14 periods, of 14 days each, during the years of 2014 and 2015. The environmental variables and leaf traits during the exposure periods were described by mean, median, standard deviation and minimum and maximum values. Spearman correlation and multiple linear regression analyses were applied on data from exposure periods. Leaf injury index, leaf area, leaf dry mass, temperature, relative humidity, global solar radiation and accumulated rainfall were used in the regression analyses to select the best models for predicting O3 concentrations. Leaf injury characteristically caused by O3 was verified in all areas and periods of plant exposure. Higher values of leaf injury (24.5% and 27.7%) were registered in the 13th and 12th exposure periods during spring and in areas influenced by urban and industrial clutches. The VPD, temperature, global solar radiation and O3 were correlated to leaf injury. Environmental variables [leaf area, leaf dry mass, global solar radiation and accumulated rainfall] and primarily the VPD were fundamental to improve the adjustments done in the bioindicator model (R2 ≥ 0.73). Our research shows that biomonitoring employing the tobacco “Bel-W3” can be improved by measuring morphological leaf traits and meteorological parameters. Additionally, O3 fumigation experiment should be performed with biomonitoring as conducted in this study, which are useful in understanding the role of other environmental factors.

Passiflora edulis Sims is a liana species of high economic interest and is an interesting model plant for understanding ozone action on disturbed vegetation. In this work we hypothesized that P. edulis has adaptive responses to oxidative stress that enable it to tolerate ozone damage based on its capacity to grow under a diversity of environmental conditions and to dominate disturbed areas. We exposed seedlings to three levels of ozone in a Free-Air Controlled Exposure (FACE) system (22, 41 and 58 ppb h AOT40 and 13.52, 17.24 and 20.62 mmol m−2 POD0, over 97 days) for identifying its tolerance mechanisms. Anatomical (leaf blade structure and fluorescence emission of chloroplast metabolites), physiological (leaf gas exchange, growth rate and biomass production) and biochemical (pigments, total sugars, starch, enzymatic and non-enzymatic antioxidant metabolites, reactive oxygen species and lipid peroxidation derivatives) responses were assessed. Ozone caused decreased total number of leaves, hyperplasia and hypertrophy of the mesophyll cells, and accelerated leaf senescence. However, O3 did not affect carbohydrates content, net photosynthetic rate, or total biomass production, indicating that the carboxylation efficiency and associated physiological processes were not affected. In addition, P. edulis showed higher leaf contents of ascorbic acid, glutathione (as well high ratio between their reduced and total forms), carotenoids, and flavonoids located in the chloroplast outer envelope membrane. Our results indicate that P. edulis is an O3-tolerant species due to morphological acclimation responses and an effective antioxidant defense system represented by non-enzymatic antioxidants, which maintained the cellular redox balance under ozone.

Background and aimsThe Brazilian Atlantic forest has been affected by the deposition of Ni and Zn, among other heavy metals adsorbed from atmospheric particles, which can be incorporated into the soil. If available in the soil, they can be absorbed by plant roots. The study aimed at testing experimentally the hypotheses: 1) Ni and Zn depositions increase their bioavailable fractions in the soil; 2) pioneer tree species demonstrate a greater potential to absorb Ni and Zn from the soil and less growth changes than non-pioneer species.MethodsThe experiment was carried out with six pioneer and non-pioneer species native to the Atlantic Forest, grown for 90 days in soil from an urban fragment of the Atlantic Forest, according to the treatments: soil with balanced fertilization (control) and soil enriched with Ni, Zn and Ni+Zn. At the end, the concentrations of Ni and Zn were determined in four soil fractions (F1: soluble; F2: linked oxides/hydroxides; F3: organic matter: F4: residual metals) and in leaves, stems/branches and roots. Mobility factors in soil, concentration ratios between treatments and respective controls, translocation index and relative growth rate in height, leaf number and total biomass were also calculated.ResultsThe results showed that Ni and Zn concentrations increased significantly in the bioavailable soil fractions (F1, F2). The absolute content of Ni and Zn in the plants directly reflected the soil level in the available forms.ConclusionsThe metal accumulation in the species occurred regardless of the successional group to which they belonged. Non-pioneer species showed greater susceptibility to the metals.

Soil pollution by heavy metals is a worldwide environmental concern. Owing to their proximity to sources of anthropogenic emission, urban forest fragments are highly affected by the excessive input of heavy metals into the soil. Thus, this study aimed to assess the physiological and biochemical responses of two native Brazilian Atlantic Forest tree species, Schinus terebinthifolia Raddi (pioneer species) and Eugenia uniflora L. (non-pioneer species), when cultivated in soils contaminated with Cu. Plants were cultivated in soils of an urban forest fragment contaminated with 0 (control), 60, 120, 180 or 240 mg Cu kg−1 soil. Growth variables, Cu content in plant tissues, translocation index, bioaccumulation factor, pigment contents, leaf gas exchange and chlorophyll fluorescence were all measured to assess physiological alterations resulting from Cu stress, while enzymatic (superoxide dismutase) and nonenzymatic (ascorbic acid and glutathione) antioxidants were quantified to assess the biochemical responses of the species. Both species presented high uptake and accumulation of Cu in roots with low translocation rates to shoots; however, S. terebinthifolia showed higher Cu restriction in roots than E. uniflora. S. terebinthifolia and E. uniflora showed distinct responses in growth and leaf gas exchange. Neither enzymatic contents nor oxidative reduction showed any difference between the species. The restriction of Cu in roots appears to be the principal protective mechanism against Cu phytotoxicity, preventing negative effects on the physiological and biochemical status of the species. S. terebinthifolia shows potential as a Cu phytostabilizer.

Context Soil pollution by heavy metals is a worldwide environmental concern. Owing to their proximity to anthropogenic emission sources, urban forest fragments are highly affected by the excessive input of heavy metals into the soil.Objectives This study aimed to assess the physiological and biochemical responses of two native Brazilian Atlantic Forest Schinus terebinthifolia Raddi (pioneer species) and Eugenia uniflora L. (non-pioneer species), when cultivated in soils contaminated with Cu. Methods Plants were cultivated in soils of an urban forest fragment contaminated with 0 (control), 60, 120, 180 or 240 mg Cu kg-1 soil. Growth variables, Cu content in plant tissues, translocation index, bioaccumulation factor, pigment contents, leaf gas exchange and chlorophyll fluorescence were all measured to assess physiological alterations resulting from copper stress, while the enzymatic (superoxide dismutase) and nonenzymatic (ascorbic acid and glutathione) antioxidants were quantified to assess the biochemical responses of the species. Results Both species presented high uptake and accumulation of Cu in roots with low translocation rates to shoots; however, S. terebinthifolia showed higher Cu restriction in roots than E. uniflora. S. terebinthifolia and E. uniflora showed distinct responses in growth and leaf gas exchange. The species showed neither difference in enzymatic contents nor oxidative reduction. Conclusion The restriction of copper in roots appears to be the principal protective mechanism against copper phytotoxicity, preventing negative effects on the physiological and biochemical status of the species. S. terebinthifolia shows potential as a Cu phytostabilizer, while the E. uniflora has potential as a Cu phytoextractor.

Eugenia uniflora L. is an important fruit tree native to tropical South America that adapts to different habitats, thanks to its metabolic diversity and ability to adjust the leaf antioxidant metabolism. We hypothesized that this metabolic diversity would also enable E. uniflora to avoid oxidative damage and tolerate the enhanced ozone (O3) concentrations that have been registered in the (sub)tropics. We investigated whether carbohydrates, polyphenols and antioxidants are altered and markers of oxidative damage (ROS accumulation, alterations in leaf gas exchange, growth and biomass production) are detected in plants exposed to two levels of O3 (ambient air and twice elevated ozone level in a O3-FACE system for 75 days). Phytotoxic O3 dose above a threshold of 0 nmol m−2 s−1 (POD0) and accumulated exposure above 40 ppb (AOT40) were 3.6 mmol m−2 and 14.898 ppb h at ambient, and 4.7 mmol m−2 and 43.881 ppb h at elevated O3. Twenty-seven primary metabolites and 16 phenolic compounds were detected in the leaves. Contrary to the proposed hypothesis that tropical broadleaf trees are relatively O3 tolerant, we concluded that E. uniflora plants are sensitive to elevated O3 concentrations. Experimental POD0 values were lower than the critical levels for visible foliar O3, because of low stomatal conductance. In spite of this low stomatal O3 uptake, we found classic O3 injury, e.g. reduction in carbohydrates and fatty acids concentrations; non-significant changes in the polyphenol profile; inefficient antioxidant responses; increased contents of ROS and indicators of lipid peroxidation; reductions in stomatal conductance, net photosynthesis, root/shoot ratio and height growth. However, we also found some compensation mechanisms, e.g. increased leaf concentration of polyols for protecting the membranes, and increased leaf number for compensating the decline of photosynthetic rate. These results help filling the knowledge gap about tropical tree responses to O3.

In the tropical region, the greatest challenge of the biomonitoring approach is to establish linear relationships between biomarkers measured in plants and pollutant concentrations, since the bioindicator responses can be intensified or restricted by climatic variations. In southeastern Brazil, there are two regions affected by air pollution, where the Atlantic Forest remains and should be preserved. Consequently, both areas have been monitored by biomonitoring procedures using standardized and tropical plants. The industrial complex settled in Cubatão is one of the world's most famous examples of environmental pollution and degradation, with consequent decline of the Atlantic Forest. An oil refinery is among the most polluting industries in the Cubatão region. The other region is located in the Metropolitan Region of Campinas (MRC). The MRC has been affected by high levels of air pollutants originated from road traffic and is responsible for over 80% of CO, NOx, and hydrocarbon emissions and develops industrial activities that emit about 70% of the particulate matter present in the region. Both regions are distinguished by the climate, despite the fact that they are only about 130 km far from each other. Several studies carried out by our group in these regions aimed to establish the best native tree species and respective potential biomarkers for future assessment of pollution effects on tropical Forests. We present a critical review about the efficiency of native species compared to standardized bioindicator plants considering antioxidant defense system, nutrient accumulation, and microscopic aspects when exposed to atmospheric pollutants and climate.

Elevated levels of ground-level ozone threaten terrestrial ecosystems and biodiversity., Elevated tropospheric ozone concentrations induce adverse effects in plants. We reviewed how ozone affects (i) the composition and diversity of plant communities by affecting key physiological traits; (ii) foliar chemistry and the emission of volatiles, thereby affecting plant-plant competition, plant-insect interactions, and the composition of insect communities; and (iii) plant-soil-microbe interactions and the composition of soil communities by disrupting plant litterfall and altering root exudation, soil enzymatic activities, decomposition, and nutrient cycling. The community composition of soil microbes is consequently changed, and alpha diversity is often reduced. The effects depend on the environment and vary across space and time. We suggest that Atlantic islands in the Northern Hemisphere, the Mediterranean Basin, equatorial Africa, Ethiopia, the Indian coastline, the Himalayan region, southern Asia, and Japan have high endemic richness at high ozone risk by 2100.

This study aimed to evaluate the accumulation and distribution of copper (Cu) in the pioneer tree Schinus terebinthifolius R. (aroeira) and non-pioneer tree Eugenia uniflora L. (pitanga) submitted to different concentrations of copper. The plants received 40 mL of Hoagland & Arnon (1950) n. 1 nutrient solution modified with 0.00032, 0.0032, 0.032 and 0.32 mM Cu2+ applied to the soil. We analyzed biomass, biometry and Cu contents in plants and the concentration of Cu in soil. Cu concentration in the soil contaminated with 0.32 mM Cu2+ was higher than other treatments. Neither species showed characteristics of plant phytotoxicity. However, the two species did exhibit different physiological responses to Cu; S. terebinthifolius accumulated the metal only in roots, while E. uniflora accumulated Cu in roots and leaves. The highest Cu concentration in soil was observed in the treatment with 0.32 mM Cu2+. Outstanding to foliar accumulation, E. uniflora could be used for biomonitoring.

The expansion of land use for agricultural interests and the excessive use of herbicides are among the causes of biodiversity losses in the Brazilian Cerrado biome. Therefore, we aimed to test the hypothesis that Dipteryx alata Vogel, a common species in this biome, is sensitive to nicosulfuron because of its high phytotoxicity. We evaluated physiological, biochemical and morphological responses in D. alata plants exposed to increasing doses of the herbicide. Young plants were transplanted to 10 L pots containing substrate composed of soil and sand (2:1) after fertilization. After an acclimation period, the following doses of nicosulfuron were applied: 0 (control), 6, 12, 24, 48, and 60 g a.e. ha−1. The experiment was conducted in a randomized block design factorial scheme with six doses of nicosulfuron, three evaluation times, and five replicates per treatment. The effects of the herbicide were assessed by measuring gas exchange, chlorophyll a fluorescence, photosynthetic pigments, membrane permeability, antioxidant enzymes and acetolactate synthase. Nicosulfuron altered the photosynthetic machinery and enzymatic metabolism of D. alata. Reductions in physiological traits, increased catalase and ascorbate peroxidase activities, enhanced malondialdehyde concentrations rate of electrolyte leakage and decreased acetolactate synthase activity in response to nicosulfuron all suggest that D. alata is sensitive to this herbicide.

Ground-level ozone (O3) pollution can adversely affect human health and vegetation, thus being an important environmental issue nowadays. Ozone biological monitoring (biomonitoring) is a method of O3 monitoring by observing quantitative changes in living organisms physically present in a specific environment. Here, we provide a concise view of the field of O3 biomonitoring, along with recent advances that are expected to advance this field in the future. We also recommend that O3 biomonitoring is included in citizen science initiatives as well as in worldwide curricula of educational institutions. Policy-makers and the general public may not understand biomonitoring data; hence, a major challenge is how to communicate the information to the audience in a way that permits the best comprehension.

Evaluations of ozone effects on vegetation across the globe over the last seven decades have mostly incorporated exposure levels that were multi-fold the preindustrial concentrations. As such, global risk assessments and derivation of critical levels for protecting plants and food supplies were based on extrapolation from high to low exposure levels. These were developed in an era when it was thought that stress biology is framed around a linear dose-response. However, it has recently emerged that stress biology commonly displays non-linear, hormetic processes. The current biological understanding highlights that the strategy of extrapolating from high to low exposure levels may lead to biased estimates. Here, we analyzed a diverse sample of published empirical data of approximately 500 stimulatory, hormetic-like dose-responses induced by ozone in plants. The median value of the maximum stimulatory responses induced by elevated ozone was 124%, and commonly

The tolerance potential against the oxidative injury in native plants from forest ecosystems affected by environmental stressors depends on how efficiently they keep their pro-oxidant/antioxidant balance. Great variations in plant tolerance are expected, highlighting the higher relevance of measuring biochemical leaf trait indicators of oxidative injury in species with similar functions in the forest than in single species. The use of this functional approach seems very useful in the Brazilian Atlantic Forest because it still holds high plant diversity and was the focus of this study. We aimed at determining the tolerance potential of tree species from the Atlantic Forest remnants in SE Brazil against multiple oxidative environmental stressors. We assumed that pioneer tree species are more tolerant against oxidative stress than non-pioneer tree species and that their tolerance potential vary spatially in response to distinct combined effects of oxidative environmental stressors. The study was carried out in three Atlantic Forest remnants, which differ in physiognomy, species composition, climatic characteristics and air pollution exposure. Leaves of three pioneer and three non-pioneer species were collected from each forest remnant during wet (January 2015) and dry periods (June 2015), for analyses of non-enzymatic and enzymatic antioxidants and oxidative injury indicators. Both hypotheses were confirmed. The pioneer tree species displayed biochemical leaf traits (e.g. high levels of ascorbic acid, glutathione and carotenoids and lower lipid peroxidation) that indicate their higher potential tolerance against oxidative environmental stressors than non-pioneer species. The biochemical leaf traits of both successional groups of species varied between the forest remnants, in response to a linear combination of oxidative environmental stressors, from natural (relative humidity and temperature) and anthropogenic sources (ozone and nitrogen dioxide).

A música tem sido estudada principalmente por promover alterações em seres humanos e animais, tais como controle da dor, aumento na sensação de bem-estar, diminuição da fadiga e da ansiedade, entre outras. Pesquisas realizadas com recém-nascidos, crianças e idosos mostraram que a terapia envolvendo sons é capaz de produzir alterações fisiológicas e comportamentais como diminuição da frequência cardíaca, redução do cortisol e melhora do humor. Esses efeitos positivos também começaram recentemente a ser estudados mundialmente na Medicina Veterinária. Nela, a música tem sido utilizada e estudada como um recurso para promover o enriquecimento ambiental, atuando como reforço positivo e diminuindo os níveis de estresse dos animais durante o manejo. Esse estudo busca promover um maior conhecimento a respeito da musicoterapia e do seu uso na abordagem terapêutica e na produção animal.

The foliar accumulation and enrichment factor for 36 elements were studied in Psidium guajava 'Paluma' (fruit tropical tree) and Tibouchina pulchra Cogn. (native tree of the Atlantic rainforest) plants exposed around the city of Cubatão/Brazil, to propose a biomonitoring species in the Atlantic rainforest. The field experiments were conducted in six sites from November/2009 to April/2011. Parallel exposures of plants to filtered air in open-top chambers were performed to determine the background leaf concentrations of all elements. Both plants were enriched with elements (Ni, La, Fe, Ba, Al, Co, Pb, Hg and Mn) that characterize the industrial area of Cubatão, Brazil. P. guajava is a better option for biomonitoring toxic elements in Cubatão, since it was able to enrich higher metal levels than T. pulchra. Furthermore, P. guajava showed a better spatial and temporal variations in metal levels Cubatão.

Tibouchina pulchra (Cham.) Cogn., a pioneer tree species commonly found in the Atlantic Rain Forest in southeast Brazil, proved to be a promising biosensor species for indicating the potential effects of air pollution on this type of forest. This study aimed to investigate whether the present levels of nitrogen oxides, sulfur oxides, ozone and particulate matter in industrial and urban areas in the Cubatao region induce structural and ultrastructural changes in this species, to explore the synergy between air pollutants and the effects of other environmental stressors as contributors to microscopic symptoms and to verify whether these changes are seasonally dependent. The field study consisted of exposing potted saplings of T. pulchra in three sites around the petrochemical industry (industrial area), in downtown Cubatao (urban area) and in a site far from the industrial emissions (reference area). An experimental study using open top chambers (OTC) with filtered air and non-filtered air was also carried out to confirm the field results. Four exposure periods of 12 weeks were conducted during the field and the OTC experiments, covering wet and dry periods. The effects were more pronounced in plants exposed in the industrial areas during the dry period, which were confirmed by OTC experiments. Crystal density variations were linearly explained by decreases in NO 2 , SO 2 and the sum of all hourly concentrations of ozone (SUM00), as well as increases in PM 10 , relative humidity and rainfall. Variations in lipid peroxidation correlated positively with air temperature and SUM00. Tannins and starch grains decreased. Collapsed and sinuous cell walls, dense cytoplasm, invagination of plasma membranes and vacuome were the main effects observed at the structural level. Occurrence of pectic warts, alterations in chloroplasts and numerous vesicles close to the cell walls were the main ultrastructural effects detected. These results confirmed that pollutants and environmental variables acted synergistically to induce oxidative stress in this species, enhancing our understanding of the bioindicator potential of T. pulchra for monitoring complex mixtures of air pollutants in the tropics.

The antioxidant responses in saplings of Tibouchina pulchra (a native tree from the Brazilian Atlantic Rainforest) exposed around an oil refinery in the city of Cubatão (SE Brazil), varied during the exchange of its power generation source, from boilers fueled with oil to a thermoelectric fueled with natural gas. The redox potential changed in response to an interaction of air pollution and meteorological parameters, indicating that the pro-oxidant/antioxidant balance was not reached after the exchange of the power generation system. The gain in environmental quality in the region was not achieved as expected due the technological modernization, at least relative to oxidative stressors. These conclusions were based on results of analyses of enzymatic antioxidants: superoxide dismutase (SOD), ascorbate peroxidase (APX), catalase (CAT), glutathione reductase (GR); non-enzymatic antioxidants: reduced, oxidized and total ascorbic acid (AsA, DHA, totAA) and glutathione (GSH, GSSG, totG), their redox state (AsA/totAA and GSH/totG) and an indicator of lipid peroxidation (MDA). We also applied exploratory multivariate statistics in order to verify if the temporal sequence of changes in the plant redox capacity coincided with changes in the profile of air pollution, climatic conditions or with their interactions and if the environmental benefits that would supposedly be promoted by the mentioned exchange of power generation system were achieved in the region.

Tropical forest ecosystems may be subjected to climate-origin oxidative stress as it is observed in Southeast Brazil. The region is characterized by seasonal climate with well-defined wet and dry periods. Anthropogenic air pollutants are additional oxidative stress sources in these ecosystems. However, the tolerance of Brazilian tree species to oxidative stress is still unknown. Thus, the current field study aims to comparatively establish the range of antioxidant responses of ascorbate-glutathione cycle in Astronium graveolens , Croton floribundus and Piptadenia gonoacantha adult trees exposed to air pollutants and seasonal tropical climate as indicators of their increasing tolerance to oxidative stress. These are the most abundant species in the semideciduous Atlantic Forest, in Southeast Brazil. Variations in biochemical leaf traits (antioxidant defenses: ascorbate peroxidase, catalase, superoxide dismutase, glutathione reductase, ascorbate and glutathione; pigments: chlorophyll a, b and carotenoid; oxidative damage indicators: hydrogen peroxide and lipid peroxidation indicator) were determined. The native Brazilian tree species revealed distinct biochemical patterns in response to environmental oxidative stress during the wet and dry seasons. Biochemical leaf traits changed mainly in response to photoxidative stress, during the wet season. This variation was stimulated by better climate conditions to photosynthesis and plant growth, such as high light energy, water availability and temperatures. Catalase seemed to be the biochemical leaf tolerance indicator in all species during the wet season. The environmental conditions during the dry season, either of natural or anthropogenic origin, were stressful to the Brazilian tree species. They induced several changes in their biochemical leaf traits. Such changes were indicated by multilinear regression analyses. Oxidative/antioxidative imbalances, such as increased lipid peroxidation and decreased glutathione as well as the chlorophyll contents, were the most appropriate oxidative stress indicators during the dry season. C. floribundus was the most efficient species in terms of oxidative stress tolerance and it was followed by A. graveolens and P. gonoacantha .

Passive biomonitoring was applied in four Atlantic forest plots in southeast Brazil, affected by different levels of trace metal pollution (OP site located in Minas Gerais State and PEFI, PP and STG located in Sao Paulo State). Native tree species were selected as biomonitors according to their abundance in each plot and successional classification. Current trace metal concentrations in total suspended particles, leaves of non-pioneer (NPi) and pioneer (Pi) species, topsoil (0–20 cm) and litter and concentration ratios at the plant/soil interface were analyzed to verify the atmosphere-plant-soil interactions, basal concentrations, spatial variations and metal accumulation at the ecosystem level. Redundant analysis helped to identify similar characteristics of metal concentrations in PP and PEFI, which can be influenced by the high concentrations of elements related to anthropogenic inputs. Analysis of variance and multivariate statistics indicated that the trees of OP presented higher concentrations of Cr, Fe, Mn and Ni than those in the other sites. High enrichment of Cd, Fe, Ni in non-pioneer plants indicated that the PP forest (initially considered as the least polluted) has still been affected by metal pollution. Soil collected in STG was enriched by all elements, however these elements were low available for plant uptake. Metal deposited in leaves and litter was an important sink for soil cycling, nevertheless, these metals are not bioavailable in most cases. Non-pioneer tree species revealed to be more appropriate than pioneer species to indicate the current panorama of the contamination and bioavailability levels of trace metals in the tree community-litter-soil interface of the Atlantic forest remnants included in this study.

This study was conducted with the purpose to evaluate the hypothesis that the air pollution deposition in the remaining Brazilian Atlantic Forest surrounded by diversified land uses, has altered the nutritional status of its tree species. The leaf concentrations of macronutrients and micronutrients were determined to estimate Concentration Factors – CF (plant/soil concentration ratios) and leaf nutrient ratios (N/P, N/K, N/Ca, N/Mg, N/S, S/K, S/Ca, S/Mg) of the most abundant tree species found in four remnants at the Metropolitan Region of Campinas, SE Brazil: Cosmopolis, Holambra, Paulinia and Campinas. The leaf samplings occurred during three dry and wet seasons. Multivariate analysis of variance (MANOVA) determined if CF for nutrients and ratios varied between forest remnants and seasons. Variations in CF values indicated that the nutritional status of the forest remnants is defined by both physical/chemical soil attributes and atmospheric deposition. The clay soils of the Campinas forest appeared to provide the highest buffering capacity against acidic deposition and nutritional imbalances induced by the anthropic activities. The air pollution emissions from diversified land uses has increased the CF medians above a reliable baseline of the nutritional plant/soil relationship in the forest remnants studied. Agriculture activities seemed to be responsible for increasing P, K, Ca, and Mg depositions; industries for N, S and Mn depositions; soil resuspension for Ca, Fe and Mg. Considering these sources, Paulinia and Campinas seemed to be the most and least forest remnants affected by air pollution, respectively.

Editorial.

Polycyclic aromatic hydrocarbons (PAHs) are toxic to living organisms. They can accumulate on foliar surfaces due to their affinity with apolar organic compounds, which enables the use of native plant species as sentinels of atmospheric PAH deposition in polluted ecosystems. The present study extends the knowledge about this subject in the tropical region by focusing on the PAH accumulation in the foliage of dominant tree species (Astronium graveolens, Croton floribundus, Piptadenia gonoacantha) in four remnants of Semi-deciduous Atlantic Forest surrounded by diversified sources of PAHs and located in the cities of Campinas, Paulinia, Holambra and Cosmopilis (central-eastern part of Sao Paulo State, SE-Brazil). Leaves of the tree species were collected in the forest remnants during the wet and dry seasons (2011 to 2013). All samples were analyzed by high performance liquid chromatography (HPLC) coupled to a fluorescence detector for identification of 14 PAHs. The native tree species showed distinct capacities to accumulate PAHs. All of them accumulated proportionally more light PAHs than heavy PAHs, mainly during the dry period. P. gonoacantha was the most effective accumulator species. Higher accumulations of most of the PAHs occurred during the dry periods. The predominance of moderately (1 ≤ EF < 5) to highly enriched (EF ≥ 5) leaf samples of P. gonoacantha with regard to BaA and PHE in all of the forest remnants indicated that vehicular sources were widely distributed in the entire region. The predominance of the moderate to high enrichment of ACE in leaf samples from the forest remnants located in Paulinia, Holambra and Cosmopolis indicated that they were also affected by emissions from petrochemical industries.

The expansion of agricultural, urban and industrial areas in the Sao Paulo State (SE Brazil) led to the fragmentation of the original semideciduous Atlantic Forest into small, patchy forest remnants. Anthropogenic activities produce a variety of pollutants affecting many ecological processes in these remaining forest fragments through soil acidification and fertilization. In this study, we investigated the soil chemical and physical status of six forest remnants (Paulinia, Holambra, Americana, Jaguariuna, Campinas and Cosmopolis) differently affected by industrial, rural and urban pollution in central-eastern Sao Paulo in order to determine the soil potential to buffer the inputs of pollutants. Soil samples from 0-10, 10-20 and 20-40 cm depths were collected in the dry and the wet season and the following variables were analyzed: soil texture, pH in CaCl2 solution, exchangeable cations and exchange capacity, organic carbon, total nitrogen, extractable sulfur, phosphorus and heavy metals. Distinct buffering capacities were observed in industrial and in rural and urban areas, primarily due to the natural characteristics of the soils, such as soil texture, acidification and organic matter. The forest soils affected by atmospheric deposition from the industrial complex (Paulinia and Americana) were more sandy and acidic (pH = 3.6) than those near rural and urban sources (pH = 4.5). The optimal chemical conditions (high contents of organic matter, exchangeable bases, nitrogen, phosphorus and sulfur) were found in the clay soils of forest remnants located in Campinas and Jaguariuna, which were more affected by rural or urban pollution than by industrial emissions. Such clay soils provide the highest buffering capacity against environmental impacts in the study region.

Tillandsia usneoides is an epiphytic bromeliad that has been used as a universal bioindicator. The species accumulates metals and presents foliar scale variations when exposed to air pollutants. This study aimed to use the variations in foliar scales as microscopic markers of pollutant effects in the Metropolitan Region of Campinas (MRC), São Paulo State, Brazil. T. usneoides plants were exposed for 12 weeks during dry and wet seasons, totaling four exposures, at five sites in the MRC. Samples were selected before each exposure for initial evaluation of the plants (T0). Leaf fragments were fixed in glutaraldehyde and total scale density and anomalous scale percentage were evaluated. Plants exposed in the MRC showed anomalies and changes in number of subperipheral cells of leaf scales. When compared to T0, T. usneoides presented higher total scale density and anomalous scale percentage at disturbed sites, thus the species can be used as a pollution bioindicator for MRC. RESUMO A bromélia epífita Tillandsia usneoides vem sendo utilizada como bioindicadora universal por acumular altas concentrações de metais e apresentar alterações nas escamas foliares quando expostas a ambientes poluídos. Neste estudo objetivou-se utilizar alterações morfológicas nas escamas foliares como marcadores dos efeitos de poluentes aéreos na Região Metropolitana de Campinas (RMC), SP, Brasil. T. usneoides foi exposta em cinco pontos da RMC durante quatro exposições de 12 semanas, abrangendo duas exposições na estação úmida e duas na seca. Antes de cada exposição, foram selecionadas amostras para avaliação de condições iniciais das plantas (T0). Fragmentos de folhas foram fixados em glutaraldeído e avaliados quanto a densidade total de escamas e porcentagem de escamas anômalas. As plantas expostas na RMC apresentaram anomalias e alteração no número de células subperiféricas das escamas foliares. As plantas expostas em PA apresentaram maior densidade total de escamas e em PC maior porcentagem de escamas anômalas, quando comparadas às plantas T0. T. usneoides apresentou respostas relacionadas aos estresses ambientais, com maior presença de escamas anômalas e maior densidade total de escamas em plantas expostas em regiões antropizadas, portanto a espécie pode ser utlizada como bioindicadora da poluição na RMC.

This study summarizes the first effort to search for bioindicator tree species and respective potential biomarkers for future assessment of potential mixed pollution effects on the highly diverse Atlantic Forest in SE-Brazil. Leaves of the three most abundant species inventoried in a phytosociological survey (Croton floribundus, Piptadenia gonoacantha and Astronium graveolens) were collected in four forest remnants during winter and summer (2012). Their potential bioindicator attributes were highlighted using a screening of morphological, chemical and biochemical markers. The leaf surface structure and/or epicuticular wax composition pointed the accumulator properties of C. floribundus and P. gonoacantha. C. floribundus is a candidate for assessing potential accumulation of Cu, Cd, Mn, Ni, S and Zn. P. gonoacantha is a candidate to monitor polycyclic aromatic hydrocarbons. Increased levels of secondary metabolites and decreased antioxidant capacity in leaves of A. graveolens may support its value as a bioindicator for oxidative pollutants by visible dark stipplings.