|
|
|
| Registros recuperados: 54 | |
|
|
| Keiser, David A.; Mullen, Jeffrey D.; Bergstrom, John C.; Smith, Nathan B.; Radcliffe, David E.; Risse, Mark L.; Fowler, Laurie A.. |
| Water quality trading (trading) as a means to improve water quality has become an increasingly popular instrument considered by environmental policy makers. Although the U.S. Environmental Protection Agency lists more than forty current trading programs in the U.S., only a few active markets exist. The literature identifies several hurdles to trading, overcoming which requires a deeper understanding of the interaction between local environmental, legal, and economic conditions. Particular challenges include thin markets, uncertainty related to the course and fate of nutrient flows, varying degrees of political support, and high transaction costs related to market infrastructure, monitoring, and enforcement. These hindrances often arise from and... |
| Tipo: Conference Paper or Presentation |
Palavras-chave: Water quality trading; Phosphorus trading; Nutrient trading; Water pollution; Pollution markets; Environmental Economics and Policy; Land Economics/Use; Public Economics. |
| Ano: 2009 |
URL: http://purl.umn.edu/49323 |
| |
|
| |
|
|
| Ribeiro,Karina Hacke; Favaretto,Nerilde; Dieckow,Jeferson; Souza,Luiz Cláudio de Paula; Minella,Jean Paolo Gomes; Almeida,Luciano de; Ramos,Michele Ribeiro. |
| Water degradation is strongly related to agricultural activity. The aim of this study was to evaluate the influence of land use and some environmental components on surface water quality in the Campestre catchment, located in Colombo, state of Parana, Brazil. Physical and chemical attributes were analyzed (total nitrogen, ammonium, nitrate, total phosphorus, electrical conductivity, pH, temperature, turbidity, total solids, biological oxygen demand, chemical oxygen demand and dissolved oxygen). Monthly samples of the river water were taken over one year at eight monitoring sites, distributed over three sub-basins. Overall, water quality was worse in the sub-basin with a higher percentage of agriculture, and was also affected by a lower percentage of native... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Water pollution; Agriculture; Nutrients; Micro watershed. |
| Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832014000200030 |
| |
|
|
| Lopes,Fernando B.; Andrade,Eunice M. de; Meireles,Ana C. M.; Becker,Helena; Batista,Adriana A.. |
| The aim of this study was to identify spatial and temporal variations in water quality of Orós reservoir, Ceará, Brazil, as well as the sources of contamination. To get this information the Principal Component Analysis (PCA) and Cluster Analysis (CA) was used. Water samples were collected at seven (geo-referenced) points, from April 2008 to March 2011, totalling 4,032 samples. The following attributes of the waters were analysed: temperature, pH, CE, Ca2+, Mg2+, Na+, K+, Cl-, HCO3-, SO4--, turbidity, colour, Sechi transparency, TS, TVS, TFS, TSS, VSS, FSS, TDS, DO, BO5D, total phosphorus, soluble orthophosphate, EC, TTC, total ammonia, TKN, nitrate, SAR and chlorophyll-a. The PCA promoted the reduction from the 32 initial variables to 14, accounting for... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Water quality; Water pollution; Multivariate statistics. |
| Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662014000400012 |
| |
|
| |
|
| |
|
|
| Seriani, Robson; Instituto de Pesca-SP - IP/SAA.; Ranzani-Paiva, Maria José Tavares; Instituto de Pesca-SP - IP/SAA.; Gonçalves, Adriano; Centro de Aquicultura, Universidade Estadual Paulista “Júlio de Mesquita Filho"; Siqueira, Silmara Regina; Instituto de Pesca-SP - IP/SAA.; Lombardi, Julio Vicente; Instituto de Pesca-SP - IP/SAA.. |
| Selenium (Se) is described as an essential micronutrient and participates in different biological functions, as the antioxidant defense systems maintenance and regulation. However, when in high concentrations, Se may cause toxic effects as well as hematological changes in fish. The aim of the present study was to determine the toxicity of selenium in the form of sodium selenate (Na2Se6+O4) in Oreochromis niloticus based on hematological parameters, after exposure to different concentrations (0.01, 0.14 and 1.4 mg Se6+ L-1). The erythrocytic and leukocytic series were examined over 14 days at intervals of 0, 3, 5, 7,10 and 14 days. The erythrocytic series showed significant alterations in the first 7 days, including the control group. Neutrophils and... |
|
Palavras-chave: 2.07.01.00-4 haematological; Water pollution; Selenium; Toxicity Fisiologia. |
| Ano: 2012 |
URL: http://periodicos.uem.br/ojs/index.php/ActaSciBiolSci/article/view/8755 |
| |
|
|
| Cunha,Davi G. F.; Grull,Doron; Damato,Murilo; Blum,José R. C.; Eiger,Sergio; Lutti,José E.I.; Mancuso,Pedro C. S.. |
| The management of urban water resources plays an important role for developing countries. The Tietê and Pinheiros Rivers (São Paulo, Brazil) are affected by domestic and industrial effluents and by the diffuse pollution. This research aimed to quantify 134 variables in the water of Tietê and Pinheiros Rivers (approximately 7,200 and 6,600 analyses, respectively) from August 2007 to December 2008. The idea was to verify if the fact that both rivers are located in the same basin is enough to consider the application of a single management plan for both. Data showed that the rivers presented significant anthropogenic interference. The results suggested that such rivers must be subjected to individual management plans since there were exclusive occurrences... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Environmental monitoring; Metropolitan region of São Paulo (MRSP); Urban rivers; Water pollution; Water quality; Watershed management. |
| Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652011000400032 |
| |
|
|
| Marques Júnior,Aguinaldo Nepomuceno; Crapez,Mirian Araujo Carlos; Barboza,Conceição Denise Nunes. |
| The present study aimed to evaluate the water quality of the Icaraí Sewage Outfall (ISEO) area. Sampling was conducted during winter and summer, and water samples were analyzed for dissolved oxygen, pH, temperature, salinity, dissolved inorganic nutrients (DIN), seston, particulate organic matter (POM), and pigments. Results showed that the water chemistry of the area suffers temporal and spatial variation. Great variability was also seen in the C:N:P ratios of POM (August, 112:30:1; December, 59:11:1) and in the DIN concentrations. Chlorophyll-a and ammonium concentrations (4.5 µg L-1 - 71.2 µg L-1, and 0.20 µM - 52,6 µM, respectively) characterized the ISEO area as eutrophic. The dispersal of the material was not effective under certain oceanographic... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Eutrophication; Sewage outfall; Water pollution; Nutrients; Guanabara Bay. |
| Ano: 2006 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132006000500014 |
| |
|
| |
|
|
| Rubião,Cynthia Annes; Franco,Robson Maia; Mesquita,Eliana de Fátima Marques de; Miguel,Marco Antonio Lemos; Cabral,Claudius Couto; Fonseca,Ana Beatriz Monteiro. |
| ABSTRACT The aim of this study was to determine and compare the Most Probable Number (MPN) of Total Coliforms (TC), Escherichia coli and Enterococcus spp. and to characterize the antimicrobial resistance profiles of Enterococcus spp. isolated from oysters collected in the Barra de Guaratiba Mangrove, Rio de Janeiro, Brazil. The enumeration of E. coli has been used to indicate fecal contamination and hygienic-sanitary conditions of bivalve molluscs. Enterococci are capable to transfer several antimicrobial resistance genes to pathogenic bacteria, including those from Gram-negative group. The oysters were bought from local fishermen and a total of 123 individuals were analyzed. The TC, E. coli and Enterococcus spp. MPN mean were 26,300/100 g, 3,260/100 g and... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Water pollution; Escherichia coli; Enterococcus spp.; Antimicrobial resistance; Bivalve molluscs. |
| Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132017000100308 |
| |
|
| |
|
| |
|
|
| Caldelas,Cristina; Iglesia-Turiño,Santiago; Araus,Jose L.; Bort,Jordi; Febrero,Anna. |
| In the present study the physiological response of water hyacinth (Eichhornia crassipes [Mart.] Solms) to the combined exposure of excess nutrients and Hg was examined. Young water hyacinth plants were exposed to a range of HgCl2 and KNO3 concentrations. After eight weeks, submerged plant tissues reached an Hg concentration of 4 mg g-1. The accumulation of P and S was reduced by the addition of HgCl2, and also the P and K concentrations in emerged and submerged parts decreased. In contrast, the addition of HgCl2 increased Ca and Mg concentrations in submerged parts. Furthermore, the concentration ratios of submerged/emerged parts for Ca, Mg and P were also reduced by the addition of HgCl2. The interaction of HgCl2 and KNO3 was synergistic and decreased... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Abiotic stress; Metal accumulation; Multiple stress; Phytoremediation; Water eutrophication; Water pollution. |
| Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202009000100002 |
| |
| Registros recuperados: 54 | |
|
|
|
