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111.
Environmental Science and Pollution Research - Coal mining and burning activities in coal-fired power plants are among the most polluting activities in developing countries. In Brazil, the Candiota...  相似文献   
112.
Environmental Science and Pollution Research - In the European Union, more than 100,000 man-made chemical substances are awaiting an environmental risk assessment (ERA). Simultaneously, ERA of...  相似文献   
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114.
This paper analyses shrimp caught from the wild and farmed shrimp in Brazil, focusing on production, amounts exported and earnings, with comparisons drawn to all of South America and the world in general. We show that wild caught shrimp still comprises the majority of what is produced and exported in Brazil, although aquaculture has been taking a relevant role in the internal and external scenario, reaching similar levels of extraction in recent years. Despite some fluctuations in the amount of extracted shrimp, Brazil increased its production from 15,000 tons in 1950 to 80,000 in 2004. The money earned with shrimp product exportation, which includes farmed shrimp as well, followed a similar tendency. Shrimp aquaculture began late in Brazil, in 1974, and grew slowly until 1995, initiating an accelerated growing process; current estimates assume 50,000 people are employed in this activity, producing about 76,000 tons of shrimp every year. Although still incipient in relation to the world shrimp farmed production, Brazil has been assuming a relevant role in South America, yielding 44% of its total production, in 2004. Despite the importance of shrimp to the country, no studies have been conducted to explore the interrelations between the environmental and social consequences of such unplanned aquaculture growth or uncontrolled wild shrimp fishing. Based on previous observations, conflicts exist between different fishing scales. However, the consequences of shrimp farming on society (displacement from their lands, changes in the life quality, etc.) have not yet been explored. Both activities, shrimp exploitation and aquaculture, deserve better control and structure toward sustainable shrimp fishing and farming. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   
115.
Abstract: With its long history of colonization, eastern Amazonia has the highest population density in Brazilian Amazonia and represents the typical pattern of recent human occupation. Between 1991 and 1995, we surveyed the mammalian fauna at five sites, representing different degrees of human disturbance. We used line transects (1511 km surveyed) to describe differences in diversity and abundance at each site and to evaluate the effects of environmental factors. Twenty-two of the expected 44 species were recorded during surveys, but no more than 18 were recorded at any one site, and only 3 species were observed at all five sites. Despite a minimum transect length of 202 km, most species were recorded relatively infrequently at all sites, although overall sighting rates at different sites varied by more than 100%. Between-site differences were even more pronounced when we compared specific groups (e.g., arboreal, terrestrial, game, nongame), reflecting the differential effects of factors such as hunting, logging, and forest clearing. In general terms, species diversity, abundance, total biomass, and mean biomass all tended to decrease with increasing human disturbance. Two more specific patterns were also distinguished: decreasing abundance and biomass of game species with increasing hunting pressure and increasing abundance of nongame species with increasing forest disturbance. Intense hunting pressure alone may have deleterious short-term effects on abundance, but not necessarily on diversity, whereas prolonged hunting pressure, combined with forest clearing, results in marked distortions in the mammalian community. Overall, the study emphasizes the relative paucity of the mammalian fauna of eastern Amazonia, in terms of both species diversity and abundance, and its vulnerability to the ongoing process of human colonization in the region.  相似文献   
116.
Marine Protected Areas (MPAs) have been regarded as an alternative to protect natural resources and to improve fisheries. However, MPAs may also have negative socio-economic consequences on fishing communities. We aimed to check the effectiveness of a socially conflicting MPA in Brazil by assessing target reef fish biomass in islands inside (n = 6) and outside (n = 6) the MPA, fisheries’ productivity (biomass), catch per unit of effort (CPUE), and fishers’ socio-economic status (mainly fishers’ income) in three fishing communities subjected to different degrees of influence (close, average, and long distance) of the MPA. The CPUE was higher in the fishing community that was further away from the MPA, fish biomass was higher in the islands located inside the MPA in the southern region and in the islands located outside the MPA in the northern region, while fishers were making the most money closest to the MPA, where conflicts are the highest, probably from practicing very intensive fisheries. This integrated approach showed that the studied MPA has not delivered ecological benefits, such as higher CPUE or more fish, while higher income closer to the MPA could not be clearly attributed to its effects.  相似文献   
117.
The quality of the water in a uranium-ore-mining area located in Caldas (Minas Gerais State, Brazil) and in a reservoir (Antas reservoir) that receives the neutralized acid solution leaching from the waste heaps generated by uranium mining was investigated. The samples were collected during four periods (October 2008, January, April and July 2009) from six sampling stations. Physical and chemical analyses were performed on the water samples, and the data obtained were compared with those of the Brazilian Environmental Standards and WHO standard. The water samples obtained from waste rock piles showed high uranium concentrations (5.62 mg L?1), high manganese values (75 mg L?1) and low average pH values (3.4). The evaluation of the water quality at the point considered the limit between the Ore Treatment Unit of the Brazilian Nuclear Industries and the environment (Consulta Creek) indicated contamination by fluoride, manganese, uranium and zinc. The Antas reservoir showed seasonal variations in water quality, with mean concentrations for fluoride (0.50 mg L?1), sulfate (16 mg L?1) and hardness (20 mg L?1) which were low in January, evidencing the effect of rainwater flowing into the system. The concentrations for fluoride, sulfate and manganese were close or above to the limits established by current legislation at the point where the treated mining effluent was discharged and downstream from this point. This study demonstrated that the effluent discharged by the UTM affected the quality of the water in the Antas reservoir, and thus the treatments currently used for effluent need to be reviewed.  相似文献   
118.
Despite more than 20 years of economic progress, especially in emerging economies like Brazil, the gap between developed and developing countries is still large, and environment problems have risen significantly. In this context, this paper aims to make the Brazilian furniture production cleaner, analyzing the environmental requirements considered by the micro and small enterprises (SMEs) in made-to-order furniture industry during the product development process (PDP). Another attempt was to identify the internal and external factors that led to the incorporation of these requirements. In this regard, a comprehensive review of eco-design concept that consists of composing environmental requirements into the PDP, through methods, tools, guidelines and techniques, was carried out. The data were collected using semi-structured interviews and in loco observations, analyzing each activity of the PDP and the environmental requirements on 18 SMEs in Brazil. The outcomes show that the economic factors determine the way in which the enterprises respond to the environmental issues and how adequate their companies according to laws and regulations. Moreover, the small number of qualified professionals in this field lead to difficulties to structure the sector, in other words, to produce with less environment impact.  相似文献   
119.
The sorption capacity of nanoporous titanosilicate Engelhard titanosilicate number 4 (ETS-4) and silica-coated magnetite particles derivatised with dithiocarbamate groups towards Hg(II) was evaluated and compared in spiked ultra-pure and spiked surface-river water, for different batch factors. In the former, and using a batch factor of 100 m3/kg and an initial Hg(II) concentrations matching the maximum allowed concentration in an effluent discharge, both materials achieve Hg(II) uptake efficiencies in excess of 99 % and a residual metal concentration lower than the guideline value for drinking water quality. For the surface-river water and the same initial concentration, the Hg(II) uptake efficiency of magnetite particles is outstanding, achieving the quality criteria established by the Water Framework Directive (concerning Hg concentration in surface waters) using a batch factor of 50 m3/kg, while the efficiency of ETS-4 is significantly inferior. The dissimilar sorbents’ Hg(II) removal efficiency is attributed to different uptake mechanisms. This study also highlights the importance of assessing the effective capacity of the sorbents under realistic conditions in order to achieve trustable results.  相似文献   
120.
Two populations of the European bee-eater were studied, one living at a reference site and the other at a metal mining site. The concentration of arsenic and 11 metals (Al, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, and Zn) was measured in feathers and regurgitated pellets collected at both sites. Cadmium, chromium, mercury, nickel, and lead were at least twofold higher in feathers of birds from the contaminated site than in the reference site, suggesting that this population was exposed to higher metal levels. Similarly, levels of aluminum, arsenic, cadmium, cobalt, chromium, iron, and lead were also at least twofold higher in pellets from the contaminated area. The obtained results suggested that the impacted population of Merops apiaster is at risk due to the exposure to some metals.  相似文献   
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