942 resultados para Algal biofuels


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This is the Cheshire stillwaters summary results 1999 from the Environment Agency North West. In May 1997, a Stillwaters meeting was held to discuss the way forward in stillwaters monitoring. It decided upon the establishment of a three year rolling programme, in which three stillwaters would be monitored three times a year, every third year. During 1999, stillwaters monitored for the third year of the Stillwaters Monitoring Programme were Tabley Mere, Comber Mere and Norbury Mere. Surveys of Petty Pool and Betley Mere continued for a second and third year respectively after water quality concerns were highlighted in previous end-of-year reports. Oak Mere was also surveyed for the third year running due to its unusual ecology. This year, the variety of parameters monitored was limited to algal, zooplankton and water chemical samples. Fisheries and marginal invertebrate surveys were not completed due to lack of resources.

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This is the Stillwaters monitoring programme. Summary results 2001 and 2002 from the Environment Agency North West. Until January 2001 the South Area Stillwaters Sampling Programme consisted of a rolling programme where five to six stillwaters were sampled three times a year (spring, summer and autumn). However, this method was not yielding the water quality information required for long term monitoring. Local weather conditions influence short-term water quality events, e.g. algal blooms, nutrient consumption, stratification, super-saturation etc, so results from one day sampling could only be regarded as individual ‘spot’ samples. Therefore year-on-year comparisons could not be made. It was decided that long-term water quality monitoring of the stillwaters would benefit more from sampling nutrient abundance over winter months. This would give an insight into the carry-over of nutrients available for algal growth the following year and so year-on-year productivity could be assessed. Survey results shown in this report were from: The Mere, Rostherne Mere, Melchett Mere, Tabley Mere, Tatton Mere, Hatchmere, Oak Mere, Black Lake, Chapel Mere, Bar Mere, Oss Mere, Marbury Big Mere, Comber Mere and Betley Mere.

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This is the Stillwaters monitoring programme. Summary results 2003 and 2004 from the Environment Agency North West. This report is focuses in The Winter Monitoring of Stillwaters Programme, which began in January 2001 with the aim of gathering long term data on nutrient abundance over winter months. This allows assessment of nutrient ‘carry-over’ available for algal growth in the following year, plus year-on-year productivity. 14 stillwaters are monitored each year. The environmental issues associated with each Stillwater are summarised in the table below. Bank-side water samples are taken for nutrients (N, P and S) and chlorophyll. A YSI multi-parameter sonde measures temperature, pH, specific conductivity and dissolved oxygen (% saturation). Survey results shown in this report came from: Oak Mere and Bar mere.

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This is the Cheshire Stillwaters Summary results of 1999 produced by the Environment Agency on February 2000. The report highlights the water quality concerns of those areas surveyed by the Stillwaters Monitoring Programme: Oak Mere, Betley Mere, Petty Pool, Tabley Mere, Comber Mere and Norbury Mere. The report contains divided by area sections on physic-chemical characteristics and water chemistry, Algal and Zooplankton surveys, Discussion, Planned Surveys 2000 and survey maps. 1999 data from Petty Pool, Betley Mere, Comber Mere and Tabley Mere were classified by the trophic status of each stillwater as hyper-eutrophic/ eutrophic, and Oak Mere were classified as mesotrophic/ eutrophic.

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A frota de veículos movidos por biocombustíveis tem aumentado nos últimos dez anos e com isso as emissões para a atmosfera nas cidades têm sofrido alterações. Devido a esta problemática, estudos com modelos de previsão de emissões são o foco deste trabalho. Alguns modelos, homologados por agências de regulamentação de alguns países ou comunidades, servem de base para as análises de risco com auxílio de simulação.O objetivo geral deste trabalho é avaliar o impacto do uso de biocombustíveis na qualidade do ar na cidade do Rio de Janeiro e estudar cenários de qualidade do ar, em função do aumento da quantidade de biodiesel e álcool adicionada ao diesel e gasolina. Nesta dissertação, monóxido de carbono, óxidos de nitrogênio, compostos orgânicos voláteis e ozônio são os principais poluentes estudados para a cidade do Rio de Janeiro. A avaliação de cenários foi realizada empregando um modelo de qualidade do ar com base no modelo de trajetórias OZIPR e no modelo químico SAPRC. Os resultados demonstram que o aumento do uso de biodiesel diminui a concentração de ozônio na atmosfera em relação ao caso base estudado, em 10,23% utilizando a mistura BE Diesel, em 5,28% utilizando a mistura B20 e apenas 0,33% utilizando a mistura B10. Isso de fato acontece pois o biodiesel possuiu mais oxigenados na sua estrutura. O estudo revelou o aumento nas emissões e concentrações de NOx na troposfera da cidade do Rio de Janeiro, para as mistura de BE- Diesel, B20 e o B10 em relação ao caso base, foram de 5,66%, 2,83% e 0% respectivamente. Em especial na cidade do Rio de janeiro existe um consumodo O3 pelo NO presente na atmosfera urbana. A redução na concentração de CO para as misturas de BE- Diesel, B20 e o B10 em relação ao caso base, foram de 13,11%, 6,56% e 4,12% respectivamente. O aumento da disponibilidade de oxigênio presente no biodiesel produz uma melhor queima do combustível, contribuindo para uma menor concentração de CO na troposfera

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This is the report on the Effects of Water Quality in the Bassenthwaite Lake on Anglers Catches of Salmon and Sea-trout in the River Derwent April 1993 by the Institute of Freshwater Ecology. An analysis of the catch statistics for salmon and sea-trout in the Rivers Derwent and Cocker was undertaken in relation to available information on the algal water quality in Bassenthwaite Lake to test the hypothesis that poor catch returns were associated with a deterioration of water quality within the lake. Analysis of the catch statistics failed to reveal any correlation between water quality and catch returns for either species of fish and it is concluded that any water deterioration in Bassenthwaite Lake has not caused any major damage to the salmon and sea trout fisheries of the Derwent/Cocker system. This conclusion is supported by the analysis of the Windermere/Leven and Crake system, where no correlation could be found between lake water quality and downstream catches of migratory salmonid fish. However, the possibility still exists and such an effect might be detected by further field work on the macroinvertebrates and on the composition of potential salmonid spawning in the area.

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O estudo da estabilidade de emulsões de biocombustíveis destaca-se, dentre outros aspectos, pela necessidade de identificação das características destas. Esta necessidade reforça-se pela dificuldade de detecção de biodiesel e suas misturas quando estão fora de especificação, além de se aplicar aos processos de separação e purificação do biodiesel após a transesterificação. O entendimento deste problema poderá ser alcançado a partir de estudos de estabilidade associados aos modelos termodinâmicos de equilíbrio líquido-líquido (modelo NRTL) em sistemas ternários, que serão a base da modelagem proposta neste trabalho. O levantamento de dados envolve técnicas de observação direta em titulação, e ensaios de estabilidade e tensiometria, com algumas alterações das técnicas clássicas. Desta forma, o objetivo principal do trabalho é propor uma maneira de identificar e caracterizar as interfaces das emulsões formadas e estudar a estabilidade das fases envolvidas. Além disso, estuda-se a introdução de alcoóis como agentes tensoativos para viabilizar a utilização de misturas de combustíveis, mesmo na região de mais de uma fase. Para o desenvolvimento do trabalho, emulsões envolvendo os constituintes básicos serão combinadas entre si em diferentes proporções. A etapa inicial constitui-se de um mapeamento das misturas e proporções que formam as emulsões, baseadas nas curvas de equilíbrio. Em seguida, faz-se o estudo de caracterização e estabilidade destes sistemas. Com estas informações é possível mapear o sentido de incremento de tensão na interface e instabilidade da separação de fases das emulsões em relação aos diagramas ternários correspondentes. Por fim, propõe-se uma estratégia para estimar os parâmetros termodinâmicos do NRTL para as espécies presentes nos sistemas estudados e prever o comportamento dos mesmos e de sistemas similares. Este modelo matemático proposto tem como objetivo complementar a técnica experimental adotada para construção das curvas de equilíbrio, sendo bem sucedido

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•The 2013 Inter-sessional Science Board Meeting: A Note from the Science Board Chairman (pp. 1-4) •ICES/PICES Workshop on Global Assessment of the Implications of Climate Change on the Spatial Distribution of Fish and Fisheries (pp. 5-8) •PICES participates in a Convention on Biological Diversity Regional Workshop (pp. 9-11) •Social and Economic Indicators for Status and Change within North Pacific Ecosystems (pp. 12-13) •The Fourth International Jellyfish Bloom Symposium (pp. 14-15) •Workshop on Radionuclide Science and Environmental Quality in the North Pacific (pp. 16-17) •PICES-MAFF Project on Marine Ecosystem Health and Human Well-Being: Indonesia Workshop (pp. 18-19) •Socioeconomic Indicators for United States Fisheries and Fishing Communities (pp. 20-23) •Harmful Algal Blooms in a Changing World (pp. 24-25, 27) •Enhancing Scientific Cooperation between PICES and NPAFC (pp. 26-27) •Workshop on Marine Biodiversity Conservation and Marine Protected Areas in the Northwest Pacific (pp. 28-29) •The State of the Western North Pacific in the Second Half of 2012 (pp. 30-31) •Stuck in Neutral in the Northeast Pacific Ocean (pp. 32-33) •The Bering Sea: Current Status and Recent Trends (pp. 34-36) •For your Bookshelf (p. 37) •Howard Freeland takes home Canadian awards (p. 38)

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As extensas pradarias submersas formadas pelas gramas marinhas são importantes habitats da costa, onde ocorrem interações ecológicas entre diversas espécies da vegetação subaquática, invertebrados bentônicos e peixes. As gramas marinhas e algas de deriva são conhecidas como macrófitas marinhas e, por ocuparem o mesmo tipo de substrato, são normalmente encontradas juntas, proporcionando oxigênio, alimento, proteção, abrigo além de sítios de reprodução e pastagem para os animais associados a essas pradarias. Amostras de algas de deriva e de H. wrightii foram coletadas, ao longo de transectos fixos de 50 m paralelos à Ilha do Japonês, a fim de analisar a existência de relações positivas entre as espécies de macrófitas marinhas e sua macrofauna associada, comparar as duas comunidades e avaliar a estruturação da comunidade macrofaunal bêntica do local. Os transectos foram alocados de acordo com a posição do banco de grama marinha. Observou-se que a densidade de eixos e a biomassa de H. wrightii não explicam a variação da biomassa, riqueza de espécies e diversidade (Índice de Simpson) das algas de deriva. A grande movimentação das algas de deriva ao longo do banco de grama marinha faz com que elas se homogeneízem e ocupem diferentes lugares ao acaso na pradaria, muitos desses locais com baixa biomassa de H. wrightii devido à grande variabilidade na distribuição dessa espécie no local de estudo. Os descritores ecológicos da grama marinha também não tiveram relações positivas com sua macrofauna bêntica associada. A comunidade macrofaunal associada às gramas marinhas foi mais densa, rica e diversa do que a comunidade macrofaunal associada às algas de deriva. Os moluscos Anomalocardia flexuosa, Cerithium atratum, Ostrea sp, Tellina lineata e Divalinga quadrissulcata dominaram o ambiente de gramas marinhas. A maior complexidade estrutural das algas de deriva forneceu um habitat protegido mais atrativo para os crustáceos como, Pagurus criniticornis, Cymadusa filosa e Batea catharinensis. A malacofauna associada às algas não foi abundante, mas um novo registro foi a ocorrência do bivalve invasor Lithopaga aristatus, perfurando uma concha de Ostrea sp. As relações entre os descritores da biomassa algal foram comprovadas para a maioria dos descritores de sua fauna associada. As relações das macrófitas marinhas com a macrofauna total associada seguiram o mesmo padrão das relações das algas de deriva. As análises de agrupamento e ordenação mostraram que as comunidades macrofaunais bênticas do local são estruturadas de acordo com os táxons dos organismos associados mais dominantes influenciados pelo tipo de vegetação basibionte (algas de deriva ou grama marinha). Destaca-se com o presente estudo a importância de medidas de maior proteção no local para a preservação e manutenção do ecossistema da Ilha do Japonês, RJ, Brasil

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◾PICES Science in 2007 (pdf, 0.1 Mb) ◾2007 Wooster Award (pdf, 0.1 Mb) ◾FUTURE - A milestone reached but our task is not done (pdf, < 0.1 Mb) ◾International symposium on "Reproductive and Recruitment Processes of Exploited Marine Fish Stocks" (pdf, 0.1 Mb) ◾Recent results of the micronekton sampling inter-calibration experiment (pdf, 0.1 Mb) ◾2007 PICES workshop on "Measuring and monitoring primary productivity in the North Pacific" (pdf, 0.1 Mb) ◾2007 Harmful Algal Bloom Section annual workshop events (pdf, 0.1 Mb) ◾A global approach for recovery and sustainability of marine resources in Large Marine Ecosystems (pdf, 0.3 Mb) ◾Highlights of the PICES Sixteenth Annual Meeting (pdf, 0.4 Mb) ◾Ocean acidification of the North Pacific Ocean (pdf, 0.3 Mb) ◾Workshop on NE Pacific Coastal Ecosystems (2008 Call for Salmon Survival Forecasts) (pdf, 0.1 Mb) ◾The state of the western North Pacific in the first half of 2007 (pdf, 0.4 Mb) ◾PICES Calendar (pdf, 0.4 Mb) ◾The Bering Sea: Current status and recent events (pdf, 0.3 Mb) ◾PICES Interns (pdf, 0.3 Mb) ◾Recent trends in waters of the subarctic NE Pacific (pdf, 0.3 Mb) ◾Election results at PICES (pdf, 0.2 Mb) ◾A new PICES award for monitoring and data management activities (pdf, < 0.1 Mb)

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◾ Report of Opening Session (p. 1) ◾ Report of Governing Council (p. 15) ◾ Report of the Finance and Administration Committee (p. 47) ◾ Reports of Science Board and Committees: Science Board Inter-sessional Meeting (p. 63); Science Board (p. 73); Biological Oceanography Committee (p. 87); Fishery Science Committee (p. 95); Marine Environmental Quality Committee (p. 105); MONITOR Technical Committee (p. 115); Physical Oceanography and Climate Committee (p. 125); Technical Committee on Data Exchange (p. 133) ◾ Reports of Sections, Working and Study Groups: Section on Carbon and Climate (p. 139); Section on Ecology of Harmful Algal Blooms in the North Pacific (p. 143); Working Group 18 on Mariculture in the 21st Century - The Intersection Between Ecology, Socio-economics and Production (p. 147); Working Group 19 on Ecosystem-Based Management Science and its Application to the North Pacific (p. 151); Working Group 20 on Evaluations of Climate Change Projections (p. 157); Working Group 21 on Non-indigenous Aquatic Species (p. 159); Study Group to Develop a Strategy for GOOS (p. 165) ◾ Reports of the Climate Change and Carrying Capacity Scientific Program: Implementation Panel on the CCCC Program (p. 169); CFAME Task Team (p. 175); MODEL Task Team (p. 181) ◾ Reports of Advisory Panels: Advisory Panel for a CREAMS/PICES Program in East Asian Marginal Seas (p. 187); Advisory Panel on Continuous Plankton Recorder Survey in the North Pacific (p. 193); Advisory Panel on Iron Fertilization Experiment in the Subarctic Pacific Ocean (p. 197); Advisory Panel on Marine Birds and Mammals (p. 201); Advisory Panel on Micronekton Sampling Inter-calibration Experiment (p. 205) ◾ Summary of Scientific Sessions and Workshops (p. 209) ◾ Membership List (p. 259) ◾ List of Participants (p. 277) ◾ List of PICES Acronyms (p. 301) ◾ List of Acronyms (p. 303)

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Report of Opening Session (p. 1). Report of Governing Council (p. 15). Report of the Finance and Administration Committee (p. 65). Reports of Science Board and Committees: Science Board Inter-Sessional Meeting (p. 83); Science Board (p. 93); Biological Oceanography Committee (p. 105); Fishery Science Committee (p. 117); Marine Environmental Quality Committee (p. 129); Physical Oceanography and Climate Committee (p. 139); Technical Committee on Data Exchange (p. 145); Technical Committee on Monitoring (p. 153). Reports of Sections, Working and Study Groups: Section on Carbon and Climate (p. 161); Section on Ecology of Harmful Algal Blooms in the North Pacific (p. 167); Working Group 19 on Ecosystem-based Management Science and its Application to the North Pacific (p. 173); Working Group 20 on Evaluations of Climate Change Projections (p. 179); Working Group 21 on Non-indigenous Aquatic Species (p. 183); Study Group to Develop a Strategy for GOOS (p. 193); Study Group on Ecosystem Status Reporting (p. 203); Study Group on Marine Aquaculture and Ranching in the PICES Region (p. 213); Study Group on Scientific Cooperation between PICES and Non-member Countries (p. 225). Reports of the Climate Change and Carrying Capacity Program: Implementation Panel on the CCCC Program (p. 229); CFAME Task Team (p. 235); MODEL Task Team (p. 241). Reports of Advisory Panels: Advisory Panel for a CREAMS/PICES Program in East Asian Marginal Seas (p. 249); Advisory Panel on Continuous Plankton Recorder Survey in the North Pacific (p. 253); Advisory Panel on Iron Fertilization Experiment in the Subarctic Pacific Ocean (p. 255); Advisory Panel on Marine Birds and Mammals (p. 261); Advisory Panel on Micronekton Sampling Inter-calibration Experiment (p. 265). 2007 Review of PICES Publication Program (p. 269). Guidelines for PICES Temporary Expert Groups (p. 297). Summary of Scientific Sessions and Workshops (p. 313). Report of the ICES/PICES Conference for Early Career Scientists (p. 355). Membership (p. 367). Participants (p. 387). PICES Acronyms (p. 413). Acronyms (p. 415).

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Nutrient overenrichment from human activities is one of the major stresses affecting coastal ecosystems. There is increasing concern in many areas around the world that an oversupply of nutrients from multiple sources is having pervasive ecological effects on shallow coastal and estuarine areas. These effects include reduced light penetration, loss of aquatic habitat, harmfid algal blooms, a decrease in dissolved oxygen (or hypoxia), and impacts on living resources. The largest zone of oxygen-depleted coastal waters in the United States, and the entire western Atlantic Ocean, is found in the northern Gulf of Mexico on the Louisiana-Texas continental shelf. This zone is influenced by the freshwater discharge and nutrient flux of the Mississippi River system. This report describes the seasonal, interannual, and long-term variability in hypoxia in the northern Gulf of Mexico and its relationship to nutrient loading. It also documents the relative roles of natural and human-induced factors in determining the size and duration of the hypoxic zone.

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Karenia brevis is the dominant toxic red tide algal species in the Gulf of Mexico. It produces potent neurotoxins (brevetoxins [PbTxs]), which negatively impact human and animal health, local economies, and ecosystem function. Field measurements have shown that cellular brevetoxin contents vary from 1–68 pg/cell but the source of this variability is uncertain. Increases in cellular toxicity caused by nutrient-limitation and inter-strain differences have been observed in many algal species. This study examined the effect of P-limitation of growth rate on cellular toxin concentrations in five Karenia brevis strains from different geographic locations. Phosphorous was selected because of evidence for regional P-limitation of algal growth in the Gulf of Mexico. Depending on the isolate, P-limited cells had 2.3- to 7.3-fold higher PbTx per cell than P-replete cells. The percent of cellular carbon associated with brevetoxins (%C-PbTx) was ~ 0.7 to 2.1% in P-replete cells, but increased to 1.6–5% under P-limitation. Because PbTxs are potent anti-grazing compounds, this increased investment in PbTxs should enhance cellular survival during periods of nutrient-limited growth. The %C-PbTx was inversely related to the specific growth rate in both the nutrient-replete and P-limited cultures of all strains. This inverse relationship is consistent with an evolutionary tradeoff between carbon investment in PbTxs and other grazing defenses, and C investment in growth and reproduction. In aquatic environments where nutrient supply and grazing pressure often vary on different temporal and spatial scales, this tradeoff would be selectively advantageous as it would result in increased net population growth rates. The variation in PbTx/cell values observed in this study can account for the range of values observed in the field, including the highest values, which are not observed under N-limitation. These results suggest P-limitation is an important factor regulating cellular toxicity and adverse impacts during at least some K. brevis blooms.

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With the global proliferation of toxic Harmful Algal Bloom (HAB) species, there is a need to identify the environmental and biological factors that regulate toxin production. One such species, Karenia brevis, forms nearly annual blooms that threaten coastal regions throughout the Gulf of Mexico. This dinoflagellate produces brevetoxins, potent neurotoxins that cause neurotoxic shellfish poisoning and respiratory illness in humans, as well as massive fish kills. A recent publication reported that a rapid decrease in salinity increased cellular toxin quotas in K. brevis and hypothesized that brevetoxins serve a role in osmoregulation. This finding implied that salinity shifts could significantly alter the toxic impacts of blooms. We repeated the original experiments separately in three different laboratories and found no evidence for increased brevetoxin production in response to low-salinity stress in any of the eight K. brevis strains we tested, including three used in the original study. Thus, we find no support for an osmoregulatory function of brevetoxins. The original publication also stated that there was no known cellular function for brevetoxins. However, there is increasing evidence that brevetoxins promote survival of the dinoflagellates by deterring grazing by zooplankton. Whether they have other as yet unidentified cellular functions is currently unknown.