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11.
Life-long strontium patterns in otoliths of the sciaenid Micropogonias furnieri caught in the southwestern Atlantic Ocean were examined to evaluate estuarine dependency and habitat use. Otolith Sr concentrations were on average 820?±?55?μg?g?1 for freshwater, 1,751?±?101?μg?g?1 for estuarine, and ranged from 2,000 to over 4,000?μg?g?1 for marine waters. The examination of life-long otolith Sr revealed that 71?% of the marine-sampled fish moved toward brackish waters from age 0 to age 1, and that estuarine egress ranged from ages 2.1 to 4.1?years depending on the sampling area. Three different long-term patterns of Sr accumulation were observed and inferred to be the result of ontogeny and habitat shifts. Given that an estuarine Sr signature was consistently present in all sampled fish, M. furnieri is suggested to be a true estuarine-dependent species during its early life history.  相似文献   
12.
Environmental issues have been at the center of society's concerns for a long time. Recently, this kind of concern is growing even more due to the damage caused to the environment by electrical and electronic product waste. Based on this same concern, this work aimed to analyze, through a literature review, the production and treatment of electronic waste in today's world, with an emphasis on Brazil and China. The articles reviewed point to an increase in the production of this type of waste, in both Brazil and China, and reveal that the current processes of treatment of electronic waste mostly aim to obtain profit through the recovery of precious metals such as copper. This paper concluded that although Brazil is one of the major producers of e‐waste, more than 90% of its e‐waste has not had a proper final destination. This deficiency in e‐waste treatment in Brazil is mainly due to financial factors and the lack of a robust educational policy focused on the environment. Thus, this work suggests the implementation of an effective educational policy aimed at environmental conservation, as well as investments in research on recycling methods in Brazil, especially on the use of e‐waste as an aggregate in the manufacture of concrete.  相似文献   
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In general, tropical rivers have a great impact on human activities. Bioaccumulation of toxins is a worldwide problem nowadays and has been, historically, overlooked by the supervisory authorities. This study evaluated cytogenotoxic effects of Guaribas river (a Brazilian river) water during dry and rainy seasons of 2014 by using the Allium cepa test system. The toxicogenetic variables, including root growth, mitotic index, and chromosomal aberrations, were analyzed in meristematic cells of A. cepa exposed to water samples taken from the up-, within, and downstream of the city Picos (state: Piauí). The physical-chemical parameters were also analyzed to explain water quality and possible anthropogenic action. Additionally, the presence of heavy metals was also analyzed to explain water quality and possible damaging effects on eukaryotic cells. The results suggest that the river water exerted cytotoxic, mutagenic, and genotoxic effects, regardless of the seasons. In addition, Guaribas river presented physico-chemical values outside the Brazilian laws, which can be a characteristic of human pollution (domestic sewage, industrial, and local agriculture). The genetic damage was positively correlated with higher levels of heavy metals. The pollution of the Guaribas river water may link to the chemical contamination, including the action of heavy metals and their impacts on genetic instability in the aquatic ecosystem. In conclusion, necessary steps should be taken into account for further toxicogenetic studies of the Guaribas river water, as it has an influence in human health of the same region of Brazil.  相似文献   
15.
Environmental Geochemistry and Health - The Alto da Várzea radium mine (AV) exploited ore and U-bearing minerals, such as autunite and torbernite. The mine was exploited underground from 1911...  相似文献   
16.
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 effciencies (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 coefficients 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.  相似文献   
17.
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.  相似文献   
18.
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.  相似文献   
19.
This study was developed as part of the project ??Studies for Environmental and Cultural Sustainability of the Fulni-ô Medical System: Office on handling medicinal plants??. The Fulni-ô people are located in Pernambuco State, Northeastern Brazil. One of the components of this project was an ethnobotanical diagnosis of the indigenous land, where a phytosociological survey was performed in an area of Caatinga vegetation, located at Ouricuri settlement. Based on these ethnobotanical data, we calculated a conservation priority index aiming to rank species that should receive immediate attention from the Fulni-ô people. We identified 44 woody plants, 50% of which have a medicinal use. Among these, six plants were considered highly vulnerable and in need of immediate conservationist attention, in order to ensure the perpetuation of these species and the sustainability of traditional therapeutic practices of the Fulni-ô: Anadenanthera colubrina, Myracrodruon urundeuva, Lippia sp., Spondias tuberosa, Maytenus rigida, and Sideroxylon obtusifolium. We recommend the direct involvement of the Fulni-ô people in the conservation and the management of local resources by implementing a management plan and monitoring strategies for the populations of plants considered most important by the indigenous group.  相似文献   
20.
Fences are very common in rural areas, and represent important landscape elements in both tropical and temperate climate regions. In spite of their marked presence and importance, fences have been little studied, principally in Brazil. The present study examined the types of fences, the diversity of species used in their construction, as well as the diversity of their uses in a rural community in the municipality of Caruaru, Pernambuco State, northeastern Brazil. Fifty meters of fence-line in each of 50 rural properties in the community were examined, noting the diameter, height and identity of all vegetation elements used in their composition. Semi-structured interviews were also held with their builders in order to obtain information concerning fence uses. In the total of 2,500 linear meters of fence-line, 4,953 individual plant elements were identified, belonging to 51 different species. A majority of the fence elements were non-living fence posts, although the number of living posts was high. Of the total number of fence elements, 66.7% were native to the caatinga region. The large number of native species used as non-living fence posts indicates an intensive use of the caatinga vegetation and suggests the need to stimulate the use of living fence posts for conservation purposes.  相似文献   
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