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1.
Ribeira Bay is located approximately 130 km south of the city of Rio de Janeiro and receives discharges of liquid effluent from the Angra dos Reis nuclear power plant (NPP) site, where two pressurized water reactors are located. To test whether the presence of anthropogenic radionuclides in sediments in Ribeira Bay could be correlated to the NPP operations, we sampled seven sediment cores and determined accumulation rates and chronologies. Only one sediment core did not exhibit a superficial mixing layer; this sample was used for dating purposes. Cesium-137 and 207Bi were observed in this sediment profile, but their presence was associated with atmospheric fall-out rather than the nearby NPP. The exponential decay of 210Pb concentration with sediment layer depth was verified below a superficial mixing layer for all other sediment cores. Calculated accumulation rates ranged from 1.2 mm y−1 in the inner bay to 6.2 mm y−1 close to its entrance.  相似文献   

2.
Guanabara Bay is a 384-km2 coastal bay with 70% of the population of the metropolitan area of Rio de Janeiro located within its drainage basin. The water quality of the Bay is impacted by domestic and industrial runoff, of which only 15% has been adequately treated. However, based on a 14-year monitoring program, the water quality for most of Guanabara Bay remains acceptable because of intense tidal flushing, and we failed to find a worsening of conditions during the 14-year study. The inner shallow regions of the Bay, the western and northwestern parts, receive most of the drainage from metropolitan Rio de Janeiro. It is here that the water quality is alarmingly poor, characterized by hypertrophic conditions and occasional hypoxic events. Fecal coliform counts in these inner reaches of the Bay are 4–100 times higher than the maximum acceptable count for recreational waters. Hypertrophic conditions prevail in Guanabara Bay, which is characterized by low dissolved oxygen, high biochemical oxygen demand, peaks in fecal coliform, and extremely high chlorophyll-a concentrations, which reflect high quantities of nutrients entering the system. These anthropogenic pressures are a threat to planktonic and benthic communities and are reminiscent of San Francisco Bay 30 years ago. The Guanabara Bay water quality could be returned to pre-1950 conditions, but it would require sufficient political will and economic investment to ensure that at least 80–90% of the domestic and industrial sewage were treated adequately. Electronic Publication  相似文献   

3.
Environment, Development and Sustainability - In state of Rio de Janeiro, the Southeast Region of Brazil, 97.91% of the reforested areas contain exclusively species of Pinus and Eucalyptus. Due to...  相似文献   

4.
The environment is currently exposed to a large variety of man-made chemicals (e.g. for industrial, medicinal use) which have potential adverse effects to its ecological status. In addition, the densely populated areas represent local high emissions of those chemicals leading to more aggravating consequences. Estrogenic compounds that end-up in environmental water directly affect living organisms by interfering with their endocrine metabolism. The assessment of their presence in the environment requires sensitive and selective analytical methods. Nineteen estrogenic compounds belonging to different classes (5 free estrogens, 6 conjugated estrogens, 3 progestogens and 5 phytoestrogens) have been studied. The analytical methodology developed is based on solid phase extraction followed by liquid chromatography tandem mass spectrometry and has been applied to study the occurrence of the above mentioned analytes in environmental waters from the state of Rio de Janeiro (Brazil). Due to insufficient infra-structure in this region, waste waters are released onto the environment without or with incomplete previous treatment. The results show that high levels of the phytoestrogens daidzein, coumestrol and genistein of up to 366 ng/L and progesterone of up to 47 ng/L could be found in river water. Estrogens and their conjugated derivatives were detected in the lower ng/L range up to 7 ng/L. The main estrogens estrone, estradiol and the synthetic ethinyl estradiol could not be detected. The developed method showed overall good performance with recoveries above 80% (with one exception), limits of detection ≤ 2 ng/L, good linearity and reproducibility.  相似文献   

5.
The Guanabara Bay basin, SE Brazil, is shown as an experimental site to evaluate development and sustainability in coastal areas. We developed a Driver–Pressure–State–Impact–Response (DPSIR) framework in a practical context to integrate natural and socio-economic indicators. Sustainability reflects public policies towards the utilization of natural resources. Cost-benefit analysis (CBA) included in DPSIR evaluates losses and benefits resulting from such policies. CBA has some limitations due to the difficulty of valuating environmental goods and services. Instead of valuating them we propose to combine sustainability indicators and defensive expenditures for the implementation of public policies. This approach agrees with the environmental conservation paradigm implicit in sustainable development. It allows an estimation of the physical natural capital depreciation (PNCD), by using it to correct the gross domestic product (GDP) of the study area, and demonstrating the present non-sustainable characteristics of the current policies applied to the area.  相似文献   

6.
2012年是巴西里约联合国环境与发展大会20周年,回顾20年来世界各国发展所走过的路程,总结可持续发展战略的成功与不足,是制定未来世界健康发展路线图的历史要求。人们对可持续发展理论的内涵认知,经过了从生存到发展,再从发展到可持续发展的漫长过程。可持续发展被视作是一个自然—社会—经济复杂系统中的行为矢量,该矢量将导致国家或地区的发展朝向日趋合理、更为和谐的方向进化。可持续发展特别强调"整体的"、"内生的"和"综合的"内涵认知。可持续发展理论的"外部响应",是处理好"人与自然"之间的关系,这是可持续能力的"硬支撑";可持续发展战略的"内部响应",是处理好"人与人"之间的关系,这是可持续能力的"软支撑"。只有"当人类向自然的索取能够被人类向自然的回馈相平衡",只有"当人类对于当代的努力能够同对后代的贡献相平衡",只有"当人类为本区域发展的思考能够同时考虑到其它区域乃至全球利益时",可持续发展的实现才具备了坚实的基础。可持续发展揭示了"发展、协调、持续"的系统本质;可持续发展反映了"动力、质量、公平"的有机统一;可持续发展创建了"和谐、稳定、安全"的人文环境;可持续发展体现了"速度、数量、质量"的绿色运行。中国在未来不到10年的时间内,要全面实现小康社会的战略目标,达到经济更加发展、民主更加健全、科教更加发达、文化更加繁荣、生态更加良好、社会更加进步、精神更加富足,全民的生活质量更加提升,这就必然要求实现全面发展、协调发展、可持续发展,充分体现以人为本,促进人的自身完善,努力走出一条生产发展、生活富裕、生态良好的文明发展道路。论文提出了中国可持续发展战略的七大主题:始终保持经济的理性增长;全力提高经济增长的质量;满足"以人为本"的基本生存需求;调控人口的数量增长、提高人口素质;维持、扩大和保护自然的资源基础与生态容量;集中关注科技进步对于发展瓶颈的突破;始终调控环境与发展的平衡。  相似文献   

7.
Environment, Development and Sustainability - This paper estimates the genuine progress indicator (GPI) for the state of Rio de Janeiro (RJ), Brazil, from 2002 to 2016 as an alternative indicator...  相似文献   

8.
Soil respiration rates of a clay-loam textured Acrisol under different uses (Atlantic forest, manioc, horticulture and pasture) from Rio de Janeiro State were measured. The relationship between carbon dioxide (CO2) emissions and soil physico-chemical properties were investigated. Rates of CO2 emission of two sites (Atlantic forest and horticulture) were also evaluated in different seasons in 1997 and 1998. In the forest site, monthly means of measured respiration rates showed good correlation with soil temperature in the range 19.6–24.1°C (r2 = 0.89). In the horticulture site, no change was observed with soil moisture alone, in the range 3.0–13.2 wt%. In the horticulture soil, even when the surface soil was very dry, respiration rates increased in the hot, wetter summer but remained higher than the mean flux from forest soil. The CO2 emission flux of the Acrisol under different use showed good correlation with soil temperature (r2 = 0.72) and moisture (r2 = 0.61).  相似文献   

9.
The concentrations of the naturally occurring radionuclides 232Th, 238U, 210Pb, 226Ra and 238Ra were determined in the vegetables (leafy vegetables, fruit, root, bean and rice) and derived products (sugar, coffee, manioc flour, wheat flour, corn flour and pasta) consumed most by the adult inhabitants of Rio de Janeiro City. A total of 88 samples from 26 different vegetables and derived products were analyzed. The highest contribution to radionuclide intake arises from bean, wheat flour, manioc flour, carrot, rice, tomato and potato consumption. The estimated daily intakes due to the consumption of vegetables and derived products are 1.9 mBq of 232Th (0.47 microg), 2.0 mBq of 238U (0.17 microg), 19 mBq of 236Ra, 26 mBq of 210Pb and 47 mBq of 228Ra. The estimated annual effective dose due to the ingestion of vegetables and their derived products with the long-lived natural radionuclides is 14.5 microSv. Taking into account literature data for water and milk from Rio de Janeiro the dose value increases to 29 microSv, with vegetables and derived products responsible for 50% of the dose and water for 48%. 210Pb (62%) and 228Ra (24%) were found to be the main sources for internal irradiation.  相似文献   

10.
In this study we perform an ecological analysis of the resources use in the diet of the ribeirinho populations of the Barcelos municipality, Rio Negro, Amazonas, Brazil. Data on food composition, seasonality, and origin took place during three field trips between 1999 and 2000. Data were gathered based on structured interviews and observations from a total of 320 meals of 114 randomly selected families and 164 fishing trips. The staple food of the studied populations is based on fish and manioc, although the food niche amplitude can vary according to the factors such as the access to imported food items, resources seasonality, and socio-economic conditions. The migration to urban centers along with the changes in subsistence activities (reduction of small-scale agriculture and specialization in commercial fishing) may result in changes in the food habits of ribeirinho populations from Rio Negro.
Alpina BegossiEmail:
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11.
The use of cuprous fungicides in cocoa production in the southern part of the state of Bahia (Brazil) for decades has caused an accumulation of copper in various components of the cocoa plantations, and a contamination of regional freshwater ecosystems is suspected. Urban and industrial sources are supposed to contribute to water pollution and eutrophication of the Rio Cachoeira, the main river in this region. In order to study the metal contamination and nutritional status of this freshwater ecosystem, samples of the aquatic macrophytes Eichhornia crassipes and Pistia stratiotes were collected at seven sites along the river course. The samples were analysed for their copper, aluminium, chromium, nitrogen and phosphorus concentrations. The levels of heavy metals increased in the downstream direction, particularly in the roots of water hyacinth. A dramatic increase of nitrogen and phosphorus concentrations in water as well as in plant tissues was found in samples collected downstream from the city of Itabuna. Metal input and eutrophication were attributed to agricultural, industrial and urban sources in the region. Biomonitoring of the water quality using aquatic macrophytes as accumulative indicator plants is recommended in addition to chemical water analyses.  相似文献   

12.
Contributing to extant discourses about corporate environmental advocacy, this paper argues that corporations can embed discursive rhetorical strategies in material places and spaces. This argument contributes to environmental communication by bridging divisions between discursive and materialist approaches to corporate rhetoric. Corporate materiality is realized in the study of Rio Tinto Kennecott (RTK) at places of corporate community where RTK enunciates a dominant environmental discourse about the necessity of the Bingham Canyon Mine through strategies such as the technological shell game, the hypocrite's trap, and corporate heterotopia, which are made manifest materially alongside cultural values such as epistemic trust, technological progress, community, and home. Using participatory critical rhetoric as a methodology, I analyse RTK's material rhetoric at the Natural History Museum of Utah, the Rio Tinto Soccer Stadium, and the Daybreak suburban community. This case study reveals that corporations are assemblages that assert many different, and sometimes competing, arguments that can deflect environmental criticism, materially.  相似文献   

13.

In Brazil, specifically in the Doce River basin, there is still a great lack of studies on temporal and spatial trends in water quality, since the water quality in the monitoring campaigns is basically evaluated when it comes down to the concentrations of monitored variables. In this sense, the objective of this work was to perform a temporal and spatial trend analysis of water quality data in the Minas Gerais portion of the Doce River basin, Brazil. For this, the Mann–Kendall, seasonal Mann–Kendall and Spearman correlation tests were used in the temporal analysis and the cluster analysis in the spatial analysis. In the analysis of temporal trends, the analyses were performed using the values of the National Sanitation Foundation Water Quality Index (NSFWQI) and the variables that compose it. In the analysis of spatial trends, the stations were evaluated only based on the WQI. With the results of the analysis of temporal trend, it was identified that most stations did not present a statistically significant trend for the WQI. In the stations that presented trends of quality reduction, most of them are in densely populated areas, demonstrating the strong influence of the poor sanitary conditions of the municipalities to the water quality of the basin. When analyzing the variables that compose the WQI, the results found for nitrate demonstrated that water quality deterioration is also affected by the diffuse pollution originating from farming areas. The results for Escherichia coli reinforced the impact of the discharge of domestic effluents and demonstrated the absence of a significative trend is still of concern because it can represent the maintenance of a degradation state in the water bodies. In the spatial trend analysis, the CA grouped the monitoring stations into six clusters based on their similarity among the WQI values, and, together with the results of the other analyses, it was verified that the Caratinga River basin (UGRH5 Caratinga) presented the highest degree of pollution. It was also possible to identify five stations that can be reallocated or deactivated since they have similarities with other stations located in the same watercourse.

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14.
Environment, Development and Sustainability - This study provides the first quantitative assessment of seasonal variation in indoor PM2.5 in the high-air pollution risk and densely populated slums...  相似文献   

15.
Climate change and imagined futures are intricately linked, discussed by policy-makers and reported in the media. In this article we focus on the construction of future expectations in the press coverage of the 1992 and 2012 United Nations conferences in Rio de Janeiro in British and Dutch national newspapers. We use a novel combination of methods, semantic co-word networks and metaphor analysis, to study imagined futures. Our findings show that between 1992 and 2012 there was an overall shift from future-oriented hope to past-oriented disappointment regarding implementing international agreements on climate change policy, but with subtle and interesting differences between the UK and The Netherlands. Certain national differences seem to be stable over time and are indicative of rather dissimilar policy cultures in two nations which are geographically quite close.  相似文献   

16.
Produced water samples from different E&P offshore petroleum platforms, belonging to the Bacia de Campos oil field, Brazil, were analyzed for barium, 226Ra and 'Ra. The concentrations measured are in the range of 0.36-25.7 mg l(-1) for barium, 0.012-6.0 Bq l(-1) for 226Ra and <0.05-12.0 Bq l(-1) for 1Ra. A strong correlation between the concentration of barium and radium isotopes was observed (226Ra: r2=0.926: 228Ra: r2=0.785). Additionally, seawater and sediment samples were taken at different distances (from 250 to 1,000 m) from the two selected platforms. Water samples were analyzed for dissolved and particulate barium, 226Ra and 225Ra and the sediment samples for total and leachable barium, 226Ra and 228Ra. The results showed that even for the shortest sampling distance (250 m) from the discharge point, barium, 226Ra and 228Ra concentrations are similar to the local background, indicating that dispersion by local currents is enough to minimize environmental impacts.  相似文献   

17.
Previous studies have suggested that a segment of human disease may be attributable to environmental exposures. These may include exposure to chemicals released from a broad range of natural and man-made sources. The purpose of this study was to develop the sampling methodology and prepare a preliminary database on the presence of various organic chemicals in environmental media in two South Texas counties bordered by the Rio Grande River. A third county, located approximately 150 miles north of the Rio Grande River, was also sampled. The South Texas counties were the focus of study due to an increased incidence of anencephalic births in recent years. The environmental media that was sampled included surface water and sediment from the Rio Grande River and irrigation canals, as well as soil from adjacent cropland and pastures. Samples were collected using United States Geological Survey (USGS) quadrangle maps (7.5'; 1:24,000 scale) to identify the area of interest. At least one sampling location was established in each quadrangle. A pond sampler was used for the collection of surface water samples, while soil was collected with a stainless steel trowel. Sediment samples were collected directly in a glass jar. Solid samples were extracted in a soxhlet extractor using methylene chloride. Organic chemicals were concentrated from water samples on a Sep-Pak cartridge and the organics eluted with methanol/acetonitrile. Extracts were analyzed using GC-MS. All of the surface water samples contained aliphatic hydrocarbons and plasticizers, while soil samples contained aliphatics, plasticizers, pesticides, and industrial estrogens. Specific chemicals detected in environmental samples included atrazine and benzene dicarboxylic acid. Contaminant levels in sediments were generally higher than were detected in other media. The results demonstrate the broad variability of contaminant types and concentrations in environmental samples. Although this study presents only a very preliminary characterization of a large area of South Texas, the data indicate a number of pesticides and xenobiotic estrogens that were identified in environmental samples. Additional data providing more details of spatial and temporal distribution of contaminants as well as wildlife studies are needed.  相似文献   

18.
An integrated assessment of sediment quality in the Guadiamar River after a mining spill was conducted. The concentration of different metals and other conventional parameters were measured in sediments located along the river. Four sediment toxicity tests (Hyalella azteca 28-day survival and growth test; Chironomus riparius 10-day survival and growth test; Hexagenia spp. 21-day survival and growth test; and Tubifex tubifex 28-day reproduction and survival test) were carried out to determine the effects associated with the accidental spill. The geochemical fractions of 6 metals (Fe, Mn, Zn, Cu, Pb, and Cd) were determined to establish the bioavailability of the metals. The relationship found in the concentrations of metals associated with the mobile fractions of the sediments in the sites studied is similar to the toxic mud from tailing pond and confirms that the toxic effects are associated with the metals Zn and Cd originating from the spill.  相似文献   

19.
Results of groundwater and seawater analyses for radioactive ((3)H, (222)Rn, (223)Ra, (224)Ra, (226)Ra, and (228)Ra) and stable (D and (18)O) isotopes are presented together with in situ spatial mapping and time series (222)Rn measurements in seawater, direct seepage measurements using manual and automated seepage meters, pore water investigations using different tracers and piezometric techniques, and geoelectric surveys probing the coast. This study represents first time that such a new complex arsenal of radioactive and non-radioactive tracer techniques and geophysical methods have been used for simultaneous submarine groundwater discharge (SGD) investigations. Large fluctuations of SGD fluxes were observed at sites situated only a few meters apart (from 0cmd(-1) to 360cmd(-1); the unit represents cm(3)/cm(2)/day), as well as during a few hours (from 0cmd(-1) to 110cmd(-1)), strongly depending on the tidal fluctuations. The average SGD flux estimated from continuous (222)Rn measurements is 17+/-10cmd(-1). Integrated coastal SGD flux estimated for the Ubatuba coast using radium isotopes is about 7x10(3)m(3)d(-1) per km of the coast. The isotopic composition (deltaD and delta(18)O) of submarine waters was characterised by significant variability and heavy isotope enrichment, indicating that the contribution of groundwater in submarine waters varied from a small percentage to 20%. However, this contribution with increasing offshore distance became negligible. Automated seepage meters and time series measurements of (222)Rn activity concentration showed a negative correlation between the SGD rates and tidal stage. This is likely caused by sea level changes as tidal effects induce variations of hydraulic gradients. The geoelectric probing and piezometric measurements contributed to better understanding of the spatial distribution of different water masses present along the coast. The radium isotope data showed scattered distributions with offshore distance, which imply that seawater in a complex coast with many small bays and islands was influenced by local currents and groundwater/seawater mixing. This has also been confirmed by a relatively short residence time of 1-2 weeks for water within 25km offshore, as obtained by short-lived radium isotopes. The irregular distribution of SGD seen at Ubatuba is a characteristic of fractured rock aquifers, fed by coastal groundwater and recirculated seawater with small admixtures of groundwater, which is of potential environmental concern and has implications on the management of freshwater resources in the region.  相似文献   

20.
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   

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