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Registros recuperados: 154 | |
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Montalvo, J.F.; Perigó Arnaud, E.; Martínez, M.; García, I.; Esponda, S.C.; Cesar, M.E.; García, R.; López, D.; García, N.; Blanco, M.. |
Entre los años 1990 y 1991 se estudió el Golfo de Guacanayabo, desde 1998 hasta 2003 se evaluó el Golfo de Batabanó y el Archipiélago Sabana Camagüey fue investigado en la etapa 2001-2005, con el objetivo de evaluar los contenidos de nitrógeno y fósforo en estas tres regiones de la plataforma marina cubana y establecer las relaciones existentes entre ambos nutrientes. Los golfos de Guacanayabo y Batabanó poseen un mayor potencial de nitrógeno y fósforo que el ecosistema costero Sabana-Camagüey, debido al menor desarrollo de la red fluvial en este ecosistema, aunque en las tres regiones las concentraciones de estos compuestos están bajo una acentuada influencia antropogénica. La relación nitrógeno total-fósforo total N.T./P.T., mostró una tendencia a... |
Tipo: Journal Contribution |
Palavras-chave: Eutrophication; Nitrogen; Phosphorus; Man-induced effects; Archipelagoes; Eutrophication; Nitrogen; Phosphorus; Http://aims.fao.org/aos/agrovoc/c_2734; Http://aims.fao.org/aos/agrovoc/c_5192; Http://aims.fao.org/aos/agrovoc/c_5804. |
Ano: 2010 |
URL: http://hdl.handle.net/1834/3667 |
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Shi, Xiaoyong; Chen, Lili; Zhu, Chenjian; Wang, Xiulin. |
A cruise of survey in the 2008 Olympics boat-sailing field and adjacent area was carried out on August 28th, 2003. Preliminarily analysis on the eutrophication status was made on the basis of the content of dissolved inorganic nitrogen (DIN), dissolved inorganic phosphate (PO4-P),dissolved oxygen(DO) and chemical oxygen demand (COD) as well. The results indicated that in most of the survey area, water quality was in accordance with the 1st class National Seawater Standard except the average concentration of petroleum hydrocarbon which was beyond the 2nd class National Seawater Standard. The concentrations of PO4-P as well as DIN were mainly influenced by the runoff or drainage from lands, with a comparatively higher concentration in the coastal areas from... |
Tipo: Journal Contribution |
Palavras-chave: Eutrophication; Pollution; Mineral salts (nutrients). |
Ano: 2007 |
URL: http://hdl.handle.net/1834/5866 |
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Mohammed, S.M.; Björk, M.; Björklund, M.; Semesi, A.. |
The release of inorganic nutrients into the sea by domestic sewage is a major threat to many marine systems. This eutrophication affects coral-reef organisms indirectly by increased growth of microalgae, leading to increased sedimentation, decreased light availibility, rapid growth of opportunistic macroalgae, etc. In this paper, we report a decrease in the cover of important group of coral-reef builders, the coralline algae. This decrease might be caused by the outlets of sewage water from Zanzibar town. Laboratory and field experiments show that both the growth rate and the calcification of these organisms are negatively affected by high phosphate levels, but not by nitrate or ammonia. |
Tipo: Journal Contribution |
Palavras-chave: Sewage; Algae; Eutrophication; Coral reefs; Nutrients; Environmental degradation; Http://aims.fao.org/aos/agrovoc/c_5274; Http://aims.fao.org/aos/agrovoc/c_34821. |
Ano: 1995 |
URL: http://hdl.handle.net/1834/302 |
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Montalvo, J.F.; Perigó, E.. |
Coral reefs are very sensitive to the increment in nitrogen concentrations and phosphorus, since these compounds propitiate the macroalgae growth, resulting in the degradation of coral reefs. With the purpose of assessing the degree of nutriphication of the coral reefs in Los Canarreos Archipelago, located in the periphery of the Gulf of Batabanó, and those located in the outer area of Sabana-Camagüey Archipelago (SCA), three samplings were executed in the reefs of Los Canarreos Archipelago (August 1999, March 2000 and August 2000). In SCA, samplings were done in May 2002 and August 2003. The parameters evaluated were nitrates + nitrite, ammonium, total nitrogen, inorganic phosphorus and total phosphorus. The nutrient contents in the reefs located in the... |
Tipo: Proceedings Paper |
Palavras-chave: Coral reefs; Eutrophication; Nutrients (mineral); Nitrogen; Phosphorus; Coral reefs; Eutrophication; Nitrogen; Phosphorus; Http://aims.fao.org/aos/agrovoc/c_1880; Http://aims.fao.org/aos/agrovoc/c_2734; Http://aims.fao.org/aos/agrovoc/c_5192; Http://aims.fao.org/aos/agrovoc/c_5804. |
Ano: 2006 |
URL: http://hdl.handle.net/1834/2084 |
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Cabrera Páez, Y.. |
Se realizó una investigación con el objetivo de evaluar las alteraciones de los procesos biológicos en los peces que viven en sitios muy contaminados. Se aplicó una metodología basada en los efectos acumulativos de agentes estresantes múltiples a nivel de individuo en la especie Gambusia puncticulata (Poey, 1854). Este estudio se efectuó en tres sitios del río Almendares: El Rodeo, considerado como sitio de referencia, y dos sitios altamente contaminados, el Bosque de La Habana y el Puente 23. Se encontró un incremento en el largo y el peso de las hembras, y en el factor de condición para ambos sexos en los sitios más impactados. Este resultado se atribuye a la mayor disponibilidad de alimento debido a la eutrofización. El índice... |
Tipo: Theses and Dissertations |
Palavras-chave: Fishes; Biological contamination; Eutrophication. |
Ano: 2007 |
URL: http://hdl.handle.net/1834/5516 |
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Regadera, R.; Gómez, Y.; García, E.; Gómez, L.. |
It is presented an analysis of several indicators of water quality in Santiago de Cuba bay and of the bacteriological state in five of its beaches. Samples were taken in surface and 8 m deep. A low transparency of the waters was detected, associated with high levels of ammonium, total phosphorus and chlorophyll. In surface the dissolved oxygen had high levels, but in 8 m there was anoxia in the most interior stations. The thermotolerant coliforms reached high concentrations in the stations of the central axis, but in the beahes, only El Níspero was not appropriate for direct contact, in accordance with the current cuban standard. By means of a principal components analysis it was determined that high ammonium and total phosphorus concentrations were... |
Tipo: Preprint |
Palavras-chave: Eutrophication; Nutrients (mineral); Pollution; Eutrophication; Pollution; Http://aims.fao.org/aos/agrovoc/c_2734; Http://aims.fao.org/aos/agrovoc/c_6077. |
Ano: 2010 |
URL: http://hdl.handle.net/1834/3572 |
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Van Damme, S.; Meire, P.. |
The Scheldt estuary is exposed to large loads of carbon and nutrients. This leads to a eutrophication problem characterized by reduced oxygen concentrations and a huge efflux of CO<sub>2</sub>. In the coastal waters a degradation of the foodchain is noted caused by excessive nutrient supply. The capacity of the estuary to polish the water is important but can not cope with the vast scale of the immissions. Restoration and development of tidal wetlands can contribute in several ways to restore the water quality. Increase of water treatment is expected to have positive ecological results. Nevertheless, restoration of the oxygen conditions might counteract some purifying processes. |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Degradation; Estuaries; Eutrophication; Food chains; Nutrients (mineral); Water quality. |
Ano: 2001 |
URL: http://www.vliz.be/imisdocs/publications/280697.pdf |
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Bortolon,Leandro; Ernani,Paulo Roberto; Bortolon,Elisandra Solange Oliveira; Gianello,Clesio; Almeida,Rodrigo Gabriel Oliveira de; Welter,Samuel; Rogeri,Douglas Antônio. |
Abstract The objective of this work was to assess the risk of phosphorus losses by runoff through an index based on the degree of P saturation (DPS), in cropland soils of Southern Brazil. Sixty-five highly representative cropland soils from the region were evaluated. Three labile P forms were measured (Mehlich-1, Mehlich-3, and ammonium oxalate), and four P sorption indexes were tested (phosphorus single sorption point and Fe+Al determined with the three extractors). Water-extractable P (WEP) was used as an index of P susceptibility to losses by surface runoff. The DPS was determined from the ratio between labile P and each sorption index. DPS values obtained from the ratio between Mehlich-1 P and the single P sorption point ranged from 1 to 25%, whereas... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Eutrophication; Runoff; Single P sorption point; Water quality. |
Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2016000901088 |
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MALASPINA,I.C.; CRUZ,C; GARLICH,N; BIANCO,S; PITELLI,R.A. |
ABSTRACT The goal of this study was to evaluate the effectiveness of diquat, both isolated and associated with copper sources (oxychloride and hydroxide) in controling the H. verticillata submerged macrophyte and the A. gracilis microalgae. For this purpose, 10.0 cm H. verticillata young branches and 300 mL of A. gracilis culture were used. The experiments were performed in laboratory and the tested diquat concentrations were: 0.1; 0.2; 0.4; 0.8; 1.2; and 1.8 mg L-1, either isolated or added with 1.0% copper oxychlorideand hydroxide, as well as a control sample. On day 3, 7, 11, 21 and 30 after application, phytotoxicity signs were evaluated and on day 60 after application, green and dry biomass production and plant length were measured. To obtain dry... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Chemical control; Water plant; Eutrophication; Phytotoxicity; Chlorophyll a. |
Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582017000100212 |
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Vesterinen, Janne; Pouta, Eija. |
Eutrophication has been commonly acknowledged as a typical problem of the Baltic Sea, but it is also emerging in Finnish inland waters. As municipal sources of nutrients have been addressed by enhancing waste water treatment, the pressure has focused to agriculture along with the adoption of the EU- Water Framework Directive, which aims to improve surface water quality to “good ecological status” by 2015. The implementation of the directive will likely affect water recreation behavior and benefits. In this study we modeled water recreation participation and water quality econometrically using a hurdle model for three activities: swimming, fishing and boating. In addition, we estimated the consumer surplus for a water recreation day using a travel cost... |
Tipo: Conference Paper or Presentation |
Palavras-chave: Water recreation; Non-market valuation; Eutrophication; Resource /Energy Economics and Policy. |
Ano: 2008 |
URL: http://purl.umn.edu/43848 |
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Schoenlein-Crusius,Iracema Helena; Moreira,Carolina Gasch; Bicudo,Denise De Campos. |
In the State Park Parque Estadual das Fontes do Ipiranga - PEFI, located in the city of São Paulo, samples of submerged mixed leaf litter were collected monthly from 10 sites with different levels of eutrophication, from October 2003 to April 2005. Some abiotic factors, such as pH, temperature, conductivity and dissolved oxygen were simultaneously measured in 20 cm deep water at each site. The leaf litter samples were washed in laboratory, cut into 1 cm² pieces and incubated in Petri dishes containing distilled sterile water for five to seven days at 15 °C to 20 °C. Twenty-four aquatic Hyphomycete species were identified, with predominance of Anguillospora crassa Ingold, Lunulospora curvula Ingold, Tetrachaetum elegans Ingold and Camposporium pellucidum... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Biodiversity; Eutrophication; Fungal diversity; Ingoldian fungi. |
Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-84042009000300003 |
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Registros recuperados: 154 | |
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