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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.
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   

3.
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   

4.
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   

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.
Radon-222 in Brazil: an outline of indoor and outdoor measurements   总被引:3,自引:0,他引:3  
This study discusses the methodology for measuring and assessing the radon concentration in indoor and outdoor environments. A research study was developed to investigate the long-term behavior of the diurnal and seasonal fluctuations of radon (222)Rn EEC (Equilibrium-Equivalent Concentration) and the influence of temperature and other climatic aspects on this behavior. The study was performed by means of both integrated and instantaneous measurements of radon and its short-lived daughter products for a period of 1 year in an indoor environment in Rio de Janeiro city, Brazil (reference environment), with continuous measurement, using a radon monitor with an alpha spectrometry detector.For a single day, a variability of about 50% could be observed in the (222)Rn EEC values measured on a hourly basis, with a maximum occurring early in the morning and a minimum in the afternoon. For the long-term period, seasonality is responsible for a two order of magnitude variability, with a maximum of 50 Bq.m(-3) in winter (dry season) and a minimum of 0.5 Bq.m(-3) in the summer months (wet season), outdoors. A negative correlation with temperature was observed. The conclusions of this experiment led to a survey of radon gas concentration in dwellings in Rio de Janeiro city, Brazil, in urban area with nearly 7 million inhabitants, through integrated sampling methods, using a Solid State Nuclear Track Detectors Technique (SSNTD). The study was conducted in different geomorphological locations in town. The radon gas concentration in Rio de Janeiro dwellings ranged from 5 Bq.m(-3) to 200 Bq.m(-3). A good correlation between indoor radon gas concentration and location of dwellings was observed. The seashore areas presented the lowest levels of indoor radon concentration, whereas the highest levels were found close to the mountains.  相似文献   

7.
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   

8.
This paper presents a framework for understanding energy issues in the context of sustainable development. It posits that there are three important ways in which energy is related to sustainable development: (a) energy as a source of environmental stress, (b) energy as a principal motor of macroeconomic growth and (c) energy as a prerequisite for meeting basic human needs. These three dimensions correspond to the three dimensions of the often-used triangle of sustainable development: environmental, economic, and social. Using this framework, the paper traces how successive environmental summits at Stockholm (1972), Rio de Janeiro (1992) and Johannesburg (2002) have dealt with energy issues. It identifies a slow, surprising and important evolution of how energy issues have been treated at these global discussions. Energy has received increasing prominence at these meetings and become more firmly rooted in the framework of sustainable development. Stockholm was primarily concerned with the environmental dimension, Rio de Janeiro focused on both the environmental and economic dimensions, and the major headway made at Johannesburg was the meaningful addition of the social dimension and the linking of energy issues to the UN's Millennium Development Goals.  相似文献   

9.
The effects of air pollution on health have been studied worldwide. Given that air pollution triggers oxidative stress and inflammation, it is plausible that high levels of air pollutants cause higher number of hospitalisations. This study aimed to assess the impact of air pollution on the emergency hospitalisation for respiratory disease in Rio de Janeiro, Brazil. The study was divided in two parts: Part I specifically addressing the air pollution assessment and Part II addressing the health assessment. Accordingly, this Part II aimed to estimate the association between the concentrations of PM10, SO2 and CO observed in Rio de Janeiro and the number of emergency hospitalisations at a central hospital due to respiratory diseases. The pollutant concentrations were measured at two different sites in Rio de Janeiro, but the excess relative risks were calculated based on the concentrations observed at one of the sites, where limits were generally exceeded more frequently, between September 2000 and December 2005. A time series analysis was performed using the number of hospitalisations, divided in three categories (children until 1 year old, children aged between 1 and 5 years old and elderly with 65 years old or more) as independent variable, the concentrations of pollutants as dependent variables and temperature, relative humidity, long term trend, and seasonality as confounders. Data were analysed using generalised additive models with smoothing for some of the dependent variables. Results showed an excess risk of hospitalisation for respiratory disease higher than 2% per 10 μg m 3 increase in PM10 concentrations for children under 5 years old, of 2% per 10 μg m 3 increase in SO2 for elderly above 65 years old and around 0.1% per 10 μg m 3 increase in CO for children under 1 year and elderly. Other studies have found associations that are in agreement with the results achieved in this study.The study suggests that the ambient levels of air pollutants experienced in Rio de Janeiro between 2000 and 2005 were linked to the number of hospitalisations for respiratory diseases among children and elderly.  相似文献   

10.
The present research investigated the relationship between nitrate–nitrogen (NO3–N) in river water and the land use/land cover (hereafter, land use) in the Teshio River watershed located in northern Hokkaido island to understand the effect of human activities such as agriculture, forestry, industry, and urbanization in the drainage basin on the river ecosystem quality and services. River water was sampled at nine points seasonally during a 2-year period and the nutrients concentration was measured. Land use profiles were estimated at two spatial scales, riparian and sub-catchment, for each sampling station. The spatial pattern of water quality in the Teshio River showed increased NO3–N levels associated with agriculture and urban expansion, and forest reduction in the watershed. Land use at the riparian scale closely reflected that at the sub-catchment scale, which masked the unique riparian buffer effect on the river water condition. The increased agricultural and reduced forest area in the riparian zone, especially in the upper middle reach, could be a possible reason for a decline of ecosystem service for the provisioning of clean water and habitat for aquatic organisms. Measures towards sustainable and more nature-friendly agricultural management are necessary in the area to protect the Teshio River ecosystem and its ecosystem services.  相似文献   

11.
This paper examines the extent of pollution in Hudiara drain water due to untreated industrial and sewage waste of India and Pakistan. Ninety-nine surface water samples from the Pakistani side of the Hudiara drain were collected during September 1997, and April and June 1998. The analytical results of the Hudiara drain samples point out the industrial and sewage inputs from India and Pakistan. Higher values of biochemical oxygen demand (BOD), chemical oxygen demand(COD), total organic carbon(TOC), and trace metals in drain samples from the Indo-Pak border clearly indicate the Indian industrial and sewage pollution. Large variations in the levels of various measured parameters (COD, BOD, TOC, pH, total soluble substances, and trace metals) were observed along the Hudiara drain in the Pakistani vicinity. These variations were due to different types of industrial effluents and small village drains. The study showed that suspended solids(SS), COD, and fecal coliform (FC) were the major pollutants. Accordingly, the most feasible alternative is to convert the drainage network to a sedimentation and temporary storage reservoir. If disinfected, the runoff water can be used for restricted irrigation. Groundwater samples taken from the drain's surrounding area have also been analyzed. Thirty percent of the samples are not fit for drinking purposes due to NO3-N, Se and FC counts as prescribed by World Health Organization (WHO) guidelines. A trilinear diagram clearly indicates the influence of surface water of the Hudiara drain on ground water; moreover, higher values of nitrate and FC clearly indicate the seepage from the Hudiara drain.  相似文献   

12.
Because the rise of cities in North America was much later than in many other parts of the world, their connections to the hinterland were influenced early in their development by railroads and steam-powered water transport. These fossil fuel-based links made it possible to widely separate the ??upstream?? autotrophic supporting systems from the heterotrophic cities. Here, we take a different look at the connection between a city (Providence, RI, USA) and its supporting natural systems by focusing on the export of industrial and metabolic wastes from the city to the ??downstream?? coastal ecosystem in Narragansett Bay. In this way, we can track the history of a city by examining the concentrations of nutrients, metals, and hydrocarbons in the water and sediments of the estuary. In the greater Providence metropolitan area at the head of Narragansett Bay, there was rapid population and industrial expansion during the 1800s without the proper infrastructure to deal with water supply for public safety and health. On the other hand, the absence of a public water supply kept industrial and metabolic wastes largely on land. However, from the fall of 1871, on with the construction of a public water supply and sewer system, human wastes began flowing into the estuary. By reconstructing the historical record of metals and other pollutants, we illustrate clear temporal and spatial gradients of urban impact on the bay. Unfortunately, while numerous studies during the 1970s and 1980s focused on documenting metal and hydrocarbon pollution in the bay, there has been little effort to quantify the impact of mitigation efforts that have greatly reduced the input of metals and hydrocarbons to the system. Nutrient reductions are more recent and ongoing.  相似文献   

13.
流域水循环是流域生态系统的核心,其中流域过境水是流域水循环的一个重要要素。通过对大量有关太湖流域水文资料的流域水平衡分析,初步探讨太湖流域过境水对流域水循环的影响。结果显示太湖流域是长江流域中受过境水强烈影响的一个子流域。在太湖流域,流域过境水的引入扩大了流域水循环总的通量,影响了流域水循环的路径,改变了流域水循环水的配置格局。同时水循环作为流域内物质运输的介质,流域过境水的引入对太湖流域内物质的运输有不可忽视的影响,其中最重要的就是影响了污染物的运输,增加了污染物在太湖当中的沉积与滞留  相似文献   

14.
By 2012, Hammarby Sjöstad, a former large industrial harbor area in southern Stockholm, Sweden, will be a fully developed residential district containing approximately 11,000 apartments and accommodating 35,000 people. The transformation of the area began in 1996, and the development soon became renowned for its ambitious environmental program, inspired by Agenda 21 (United Nations in Rio declaration on environment and development. United Nations Department of Economic and Social Affairs (DESA), Rio de Janeiro, 1992) and the Sydney 2000 Olympics in Australia (Newman in Landsc Urban Plan 44:219–226, 1999). Using results based on literature reviews, in-depth interviews, discussions with focus groups, and quantitative data, this paper attempts to gain insight into how the environmental program influenced the planning and performance of the district with regard to sustainable urban development. In doing so, three important conclusions were maintained that could be valuable for similar projects concerning the planning and development of sustainable urban districts. First, the environmental program proved vital to the development process of Hammarby Sjöstad, specifically in its drive to create a sustainable urban district. When planning on improving the sustainability of future districts, such a program should be introduced and integrated earlier in the planning stage of the district. Second, the metabolic flows of Hammarby Sjöstad were reduced as a result of the integrated system—the Hammarby Model—of Hammarby Sjöstad. In order to reduce the metabolic flows in future urban districts even further, it is important to facilitate the integration of technical innovations into existing integrated systems. Third, this case study showed that there was a loss of valid and credible data related to the aims and goals of the environmental program of Hammarby Sjöstad. In future urban districts, it is of the utmost importance to include a clear structure of the assessment process in the environmental program, which would ensure the quality of gathered data and facilitate the development of even better sustainable urban districts in the future.  相似文献   

15.
The integration of water quality monitoring variables is essential in environmental decision making. Nowadays, advanced techniques to manage subjectivity, imprecision, uncertainty, vagueness, and variability are required in such complex evaluation process. We here propose a probabilistic fuzzy hybrid model to assess river water quality. Fuzzy logic reasoning has been used to compute a water quality integrative index. By applying a Monte Carlo technique, based on non-parametric probability distributions, the randomness of model inputs was estimated. Annual histograms of nine water quality variables were built with monitoring data systematically collected in the Colombian Cauca River, and probability density estimations using the kernel smoothing method were applied to fit data. Several years were assessed, and river sectors upstream and downstream the city of Santiago de Cali, a big city with basic wastewater treatment and high industrial activity, were analyzed. The probabilistic fuzzy water quality index was able to explain the reduction in water quality, as the river receives a larger number of agriculture, domestic, and industrial effluents. The results of the hybrid model were compared to traditional water quality indexes. The main advantage of the proposed method is that it considers flexible boundaries between the linguistic qualifiers used to define the water status, being the belongingness of water quality to the diverse output fuzzy sets or classes provided with percentiles and histograms, which allows classify better the real water condition. The results of this study show that fuzzy inference systems integrated to stochastic non-parametric techniques may be used as complementary tools in water quality indexing methodologies.  相似文献   

16.
Environmental changes in Sepetiba Bay,SE Brazil   总被引:2,自引:0,他引:2  
Sepetiba Bay is an example of an aquatic environment that has been severely impacted by human occupation and industrial activities in its basin. Some 400 industries including metallurgical, petrochemical and pyrometallurgical smelters, which emitted pollutants to air, soil and water, were established in Sepetiba Basin during the past 30 years. Apart from these point sources, changes in land use have also resulted in a large remobilization of pollutant deposition on Sepetiba Bay Basin. Studies have pointed out significant changes in sedimentation rates, concentrations of inorganic pollutants (Zn, Cd, Pb and Hg) and more recently, eutrophication, pointing to this area as an example of an impacted coastal zone. Notwithstanding local sources, Sepetiba Bay also suffers environmental impacts caused by diversion of river waters from adjacent basins, with some 30% of the total Hg flux to Sepetiba Bay and a 10-fold increase in water and sediment fluxes resulting from this. Decreasing environmental quality compromises both the large biodiversity and the potential economic uses of Sepetiba Bay, including fisheries and tourism. Monitoring of heavy metal levels in organisms (algae, mollusks, crustaceans and oysters) often shows concentrations well above the limits allowed following Brazilian legislation for food quality. Historical evolution of these concentrations suggests a worsening of the situation. Failure to monitor the effect of land-based activities, including those from other basins artificially associated with Sepetiba Bay has resulted in poor scenario construction and proper management planning.  相似文献   

17.
Natural gamma radiation of beach sand deposits was measured along the south coast of Rio de Janeiro State, Brazil, with the aim of studying the provenance and transport processes of sediments in this area. Concentrations of thorium, uranium and potassium were evaluated using γ-ray spectrometry and a behavioral study of eTh/eU and eTh/K cross plots was performed, reflecting the mineralogical properties of beach sands, as well as their history of transport and sorting processes. The results show that such technique can be efficiently used to map heavy mineral distributions and to distinguish the different origins of coastal sediments disclosing the influence of nearby rivers.  相似文献   

18.
The HBV-N model was used for a scenario analysis of changes in nitrogen retention and transport caused by alterations of wetness due to land drainage, lowering of lakes, building of dams and climatic variability in a river basin in south-central Sweden (1885–1994). In general, dams were situated in locations more favourable for retention, compared to the lowered lakes. Rather modest conversions of water bodies only changed nitrogen transport by about 3%. The 180-times-larger increase of (mainly) tile-drained agricultural land had, according to simulations, increased the nitrogen transport by 17%, due to reduced retention. However, compared to human-induced alteration of the landscape N retention, the choice of 10-year periods of climatological data had the overriding effect on the calculated nitrogen transport. Weather-induced variations resulted in a 13% difference in nitrogen retention between various 10-year periods. When the model was driven by climatological data from the driest 10-year period (1905–1914), the estimated average annual load was only half of that obtained with climatological data from the wettest 10-year period (1975–1984). Electronic Publication  相似文献   

19.
This paper illustrates an innovative approach to characterize the metabolic pattern of informal urban settlements or slums with the aim to better understand the factors that affect the material standard of living of slum residents, the dynamics of slum development and the interaction of the slum with its wider socioeconomic context. The proposed system of accounting, multi-scale integrated analysis of societal and ecosystem metabolism (MuSIASEM), integrates socioeconomic and spatial data and studies energy and monetary flows in relation to the pattern of human activities and land uses. The theoretical basis of the approach is illustrated with data from Vidigal favela in Rio de Janeiro, Brazil. In particular, we show how to construct taxonomies of accounting categories to characterize: (1) the set of activities carried out by the slum dwellers, to which to link assessments of flow rates per hour; (2) the set of land uses or spatial elements making up the slum, to which to link assessments of flow densities per hectare. The analysis of the interaction of Vidigal with its wider socioeconomic context focuses on monetary flows and transport (job commuting).  相似文献   

20.
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   

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