Characterization of atmospheric aerosols in the city of S?o Paulo, Brazil: comparisons between polluted and unpolluted periods

The objective of this study was to determine the size and composition of atmospheric aerosols in the downtown area of the city of S?o Paulo, Brazil, for a polluted and an unpolluted period. Aerosols were sampled with a portable air sampler (PAS), Micro-Orifice Uniform Deposit Impactor (MOUDI), and Scanning Mobility Particle Sizer. At the study site, air quality is poor, especially during the winter, high concentrations of pollutants being emitted primarily by the light- and heavy-duty vehicle fleet. We analyzed mass, black carbon (BC), Al, Si, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Br, Rb, Sn, Zr, and Pb. During the polluted period, diurnal PM₁₀ was higher than nocturnal PM₁₀, whereas the inverse was true during the unpolluted period. The FPM was rich in BC, S, and Pb, whereas CPM was rich in Al, Si, Ca, Ti, and Fe. Mass balance was performed by category: ammonium sulfate, sodium chloride, crustal material, BC, and other. The PAS-determined FPM was mainly BC. The MOUDI-determined FPM crustal material explained more mass than did ammonium sulfate and BC during the polluted period, whereas ammonium sulfate had the largest mass during the unpolluted period. Crustal material was the major CPM component, followed by ammonium sulfate and BC. During the unpolluted period, FPM concentrations were lower, whereas those of ammonium sulfate were relatively higher, especially at night, and particle number was inversely proportional to particle size. Aerosol growth was more intense during the polluted period.     

Native medicinal plants commercialized in Brazil – priorities for conservation

A majority of the native medicinal plants that are commercialized in Brazil are harvested from natural populations. In addition to this essentially unrestrained collecting, these plants have been heavily impacted by the cutting and the fragmentation of forest formations throughout the country. Considering the limited availability of natural resources, threats to species diversity, and the necessity of conservation efforts in light of the rapid exhaustion of natural ecosystems, it is becoming exceedingly important to establish conservation priorities. The present work sought to identify the native medicinal plants harvested for industrial purposes and to establish conservation priorities for the species of highest commercial value. To that end, a survey of Brazilian industrial products that use medicinal plants was undertaken in 54 shops in the city of Recife (Pernambuco, NE Brazil). The survey noted information concerning the commercial name of the product, its plant composition and pharmaceutical presentation, therapeutic indications, as well as the laboratory that produced it. Only native species were considered. A total of 74 different native species used to produce more than 300 types of products were encountered in the present survey. Twelve species demonstrated significant versatility (Species which had the highest numbers of different therapeutic indications and body systems), and 58.33% of these plants were trees. Destructive collecting predominates (58.11%), greatly affecting taxa collected exclusively from wild populations (86.49%). The intensive use of exclusively wild species and the destructive harvesting techniques employed in gathering them create serious problems that will threaten the availability of these resources to future generations.     

Bark regeneration and tannin content in Myracrodruon urundeuva Allem?o after simulation of extractive damages��implications to management

Due to the current exploitation and consequent extinction of native medicinal plants around the world, new strategies have been proposed to address the sustainable use of this resource. Accordingly, the goal of this study is to assess the speed of bark regeneration of Myracrodruon urundeuva Allem?o and to compare the tannin content before and after tissue regeneration. Twenty individuals from an area of Caatinga in Caruaru, Pernambuco State (NE Brazil), were selected. To evaluate the speed of bark regeneration, four treatments were established, according to the area of bark removed (10 × 2, 6 × 5, 8 × 5 and 10 × 5 cm), with five replicates (five individuals of M. urundeuva Allem?o) and three treatments of tannin content (bark removed before damage, as regenerated tissue, and non-impacted bark or control). At the end of 23 months of monitoring the regeneration, we found that only seven of the 20 individuals analyzed did not fully heal. No significant correlation between the monthly percent regeneration and average monthly precipitation was found. The tannin content varied according to the quantified tissue (after damage, regenerated and control) as well as between damage classes (20 cm(2)-41.64 to 63.53 mg; 30 cm(2)-49.25 to 67.54 mg; 40 cm(2)-31.69 to 67.44 mg; 50 cm(2)-34.08 to 48.53 mg). Despite the variations found, there was no significant difference between the measurement periods (p > 0.05) or damage classes (p > 0.05). The results showed that the regeneration rate was higher in individuals belonging to the 10 × 2 and 10 × 5 cm groups and that there is no correlation between precipitation and regeneration speed. Tannin levels did not vary significantly in the tissues before damage and after regeneration.     

Dynamics of medicinal plants knowledge and commerce in an urban ecosystem (Pernambuco, Northeast Brazil)

Given the importance of markets and fairs for the commerce of medicinal plants, an ethnobotanical study was undertaken at the Caruaru Fair (Pernambuco, northeastern Brazil) to compare the richness of species sold and their values of relative importance (RI) using two datasets collected with a 4-year interval. The seasonality of these plants?? supplies was also analyzed. The Caruaru Fair is located in the 18 de Maio Park. It covers an area 40,000?m² and is used by merchants who sell several types of products, such as supplies, handicrafts, clay and aluminum utensils, shoes, clothes and medicinal plants. Semistructured interviews were carried out with the vendors who agreed to take part in the study in order to record which plants were sold and their respective indications. The plants were collected, and the species were determined. The information was analyzed with quantitative tools. A total of 169 plants were identified from both surveys, which were significantly different with regard to species richness (p?<?0.05) but did not vary in relation to species?? Relative Importance (p?>?0.05). In relation to the seasonality of the plant supply, habit may explain the lack of some species during certain periods of the year, as most of the absent plants are herbaceous. In terms of the species most sold locally, it was found that spontaneous tree species are well known and extensively commercialized.     

Bibliometric analysis of studies involving e-waste: a critical review

Environmental Science and Pollution Research - The correct destination of waste is an essential factor for sustainable development. Electronic waste, which is very toxic, is the type of waste with...     

Evaluation of the e ectiveness of horizontal subsurface flow constructed wetlands for di erent media

Two media bed (gravel and Filtralite NR) were tested in a mesocosm to evaluate the removal of organic matter (as chemical oxygen demand (COD)), ammonia (NH4-N), nitrite, nitrate and solid matter (as total suspended solids (TSS)) for a synthetic wastewater (acetate-based) and a domestic wastewater. The use of Filtralite allowed average removal rates (6–16.8 g COD/(m2 day), 0.8–1.1 g NH4-N/(m2 day) and 3.1 g TSS/(m2 day)) and removal e ciencies (65%–93%, 57%–85% and 78% for COD, NH4-N and TSS, respectively), higher than that observed in the experiments with gravel. The applied loads of COD, ammonia, nitrate and TSS seem to influence the respective removal rates but only for the treatment of domestic wastewater with higher correlation coe cients for Filtralite. Regardless the type of media bed and the type of wastewater, nitrate was completely removed for nitrogen loading rates up to 1.3 g NO3-N/(m2 day). There was no evidence of the influence of nitrate loads on the removal of organic matter.     

A global evaluation of metabolic theory as an explanation for terrestrial species richness gradients

We compiled 46 broadscale data sets of species richness for a wide range of terrestrial plant, invertebrate, and ectothermic vertebrate groups in all parts of the world to test the ability of metabolic theory to account for observed diversity gradients. The theory makes two related predictions: (1) In-transformed richness is linearly associated with a linear, inverse transformation of annual temperature, and (2) the slope of the relationship is near -0.65. Of the 46 data sets, 14 had no significant relationship; of the remaining 32, nine were linear, meeting prediction 1. Model I (ordinary least squares, OLS) and model II (reduced major axis, RMA) regressions then tested the linear slopes against prediction 2. In the 23 data sets having nonlinear relationships between richness and temperature, split-line regression divided the data into linear components, and regressions were done on each component to test prediction 2 for subsets of the data. Of the 46 data sets analyzed in their entirety using OLS regression, one was consistent with metabolic theory (meeting both predictions), and one was possibly consistent. Using RMA regression, no data sets were consistent. Of 67 analyses of prediction 2 using OLS regression on all linear data sets and subsets, two were consistent with the prediction, and four were possibly consistent. Using RMA regression, one was consistent (albeit weakly), and four were possibly consistent. We also found that the relationship between richness and temperature is both taxonomically and geographically conditional, and there is no evidence for a universal response of diversity to temperature. Meta-analyses confirmed significant heterogeneity in slopes among data sets, and the combined slopes across studies were significantly lower than the range of slopes predicted by metabolic theory based on both OLS and RMA regressions. We conclude that metabolic theory, as currently formulated, is a poor predictor of observed diversity gradients in most terrestrial systems.     

Quantitative Ethnobotany in an Atlantic Forest Fragment of Northeastern Brazil – Implications to Conservation

Two new methods for assessing temporal trends in stream-solute concentrations at specific streamflow ranges were applied to long (40 to 50-year) but sparse (bi-weekly to quarterly sampling) stream-water quality data collected at three forested mesoscale basins along an atmospheric deposition gradient in the northeastern United States (one in north-central Pennsylvania, one in southeastern New York, and one in eastern Maine). The three data sets span the period since the implementation of the Clean Air Act in 1970 and its subsequent amendments.Declining sulfate (O ₄ ^2-) trends since the mid 1960s were identified for all 3 rivers by one or more of the 4 methods of trend detection used. Flow-specific trends were assessed by segmenting the data sets into 3-year and 6-year blocks, then determining concentration-discharge relationships for each block. Declining sulfate (O ₄ ^2-) trends at median flow were similar to trends determined using a Seasonal Kendall Tau test and Sen slope estimator. The trend of declining O ₄ ^2- concentrations differed at high, median and low flow since the mid 1980s at YWC and NR, and at high and low flow at WR, but the trends leveled or reversed at high flow from 1999 through 2002. Trends for the period of record at high flows were similar to medium- and low-flow trends for Ca²⁺+ Mg²⁺ concentrations at WR, non-significant at YWC, and were more negative at low flow than at high flow at NR; trends in nitrate (NO₃ ^-), and alkalinity (ALK) concentrations were different at different flow conditions, and in ways that are consistent with the hydrology and deposition history at each watershed. Quarterly sampling is adequate for assessing average-flow trends in the chemical parameters assessed over long time periods (∼decades). However, with even a modest effort at sampling a range of flow conditions within each year, trends at specified flows for constituents with strong concentration-discharge relationships can be evaluated and may allow early detection of ecosystem response to climate change and pollution management strategies.     

The environmental attitude of the urban population living in Macapá City,Brazilian Amazon region

Environment, Development and Sustainability - The human pressure on nature makes it imperative understanding how environmental issues can influence the world view of society. The aim of the current...