Climate Research Center Research Articles

A new capability for ANTARES: 7Be by AMS for ice samples

ANSTO, in collaboration with the Australian Antarctic Division (AAD) and the Antarctic Climate and Ecosystems Cooperative Research Centre (ACE CRC), has an on-going program of 10Be (t½=1.39×106a) concentration measurement in firn and ice at Law Dome, Antarctica. In recent years snow pit samples have also been measured for 7Be (t½=53.28d) concentration as this isotope has the potential to give further insight into the transport and deposition of cosmogenic beryllium to Law Dome and so improve the use of 10Be as a proxy for solar activity. Early 7Be measurements were made by gamma-ray spectrometry (GRS) with typical counting times of 3days. In 2010, we developed the capability for 7Be/9Be measurement on the 10MV ANTARES (Australian National Tandem Accelerator for Applied Research) accelerator using carbon foil post-stripping of 7Be3+ to 7Be4+ to eliminate the 7Li isobar. We describe the method and explain the advantages of using accelerator mass spectrometry (AMS) over GRS for 7Be analysis.

Neogene aridification of the Northern Hemisphere

Research Article| September 01, 2012 Neogene aridification of the Northern Hemisphere Jussi T. Eronen; Jussi T. Eronen * 1Department of Geosciences and Geography, P.O. Box 64, University of Helsinki, Helsinki FI-00014, Finland2Biodiversity and Climate Research Centre (LOEWE BiK-F), Senckenberganlage 25, D-60325 Frankfurt am Main, Germany *E-mail: Jussi.T.Eronen@helsinki.fi. Search for other works by this author on: GSW Google Scholar M. Fortelius; M. Fortelius 1Department of Geosciences and Geography, P.O. Box 64, University of Helsinki, Helsinki FI-00014, Finland3Institute of Biotechnology, P.O. Box 56, University of Helsinki, Helsinki FI-00014, Finland Search for other works by this author on: GSW Google Scholar A. Micheels; A. Micheels 2Biodiversity and Climate Research Centre (LOEWE BiK-F), Senckenberganlage 25, D-60325 Frankfurt am Main, Germany4Senckenberg Research Institute and Natural History Museum, Senckenberganlage 25, D-60325 Frankfurt am Main, Germany Search for other works by this author on: GSW Google Scholar F.T. Portmann; F.T. Portmann 2Biodiversity and Climate Research Centre (LOEWE BiK-F), Senckenberganlage 25, D-60325 Frankfurt am Main, Germany4Senckenberg Research Institute and Natural History Museum, Senckenberganlage 25, D-60325 Frankfurt am Main, Germany Search for other works by this author on: GSW Google Scholar K. Puolamäki; K. Puolamäki 5HIIT, Department of Computer and Information Science, Aalto University, P.O. Box 15400, FI-00076 Aalto, Espoo, Finland Search for other works by this author on: GSW Google Scholar Christine M. Janis Christine M. Janis 6Department of Ecology and Evolutionary Biology, Brown University, Providence, Rhode Island 02912, USA Search for other works by this author on: GSW Google Scholar Author and Article Information Jussi T. Eronen * 1Department of Geosciences and Geography, P.O. Box 64, University of Helsinki, Helsinki FI-00014, Finland2Biodiversity and Climate Research Centre (LOEWE BiK-F), Senckenberganlage 25, D-60325 Frankfurt am Main, Germany M. Fortelius 1Department of Geosciences and Geography, P.O. Box 64, University of Helsinki, Helsinki FI-00014, Finland3Institute of Biotechnology, P.O. Box 56, University of Helsinki, Helsinki FI-00014, Finland A. Micheels 2Biodiversity and Climate Research Centre (LOEWE BiK-F), Senckenberganlage 25, D-60325 Frankfurt am Main, Germany4Senckenberg Research Institute and Natural History Museum, Senckenberganlage 25, D-60325 Frankfurt am Main, Germany F.T. Portmann 2Biodiversity and Climate Research Centre (LOEWE BiK-F), Senckenberganlage 25, D-60325 Frankfurt am Main, Germany4Senckenberg Research Institute and Natural History Museum, Senckenberganlage 25, D-60325 Frankfurt am Main, Germany K. Puolamäki 5HIIT, Department of Computer and Information Science, Aalto University, P.O. Box 15400, FI-00076 Aalto, Espoo, Finland Christine M. Janis 6Department of Ecology and Evolutionary Biology, Brown University, Providence, Rhode Island 02912, USA *E-mail: Jussi.T.Eronen@helsinki.fi. Publisher: Geological Society of America Received: 20 Dec 2011 Revision Received: 26 Mar 2012 Accepted: 01 Apr 2012 First Online: 09 Mar 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 © 2012 Geological Society of America Geology (2012) 40 (9): 823–826. https://doi.org/10.1130/G33147.1 Article history Received: 20 Dec 2011 Revision Received: 26 Mar 2012 Accepted: 01 Apr 2012 First Online: 09 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Jussi T. Eronen, M. Fortelius, A. Micheels, F.T. Portmann, K. Puolamäki, Christine M. Janis; Neogene aridification of the Northern Hemisphere. Geology 2012;; 40 (9): 823–826. doi: https://doi.org/10.1130/G33147.1 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract Neogene cooling and aridification in the Northern Hemisphere have long been recognized, but there are no studies comparing patterns of aridity gradients or differences between North America and Eurasia. Large herbivorous mammals are an excellent source for understanding large-scale environmental and climatic patterns because their molar crown height (hypsodonty) reflects both habitat and precipitation. The temporal development of hypsodonty in the North American Great Plains is well studied, but both spatial detail and comparisons with patterns in Eurasia are lacking. Here we use a methodology based on community levels of hypsodonty to estimate precipitation during the Neogene (the past 23 Ma). We show that aridification was more profound and occurred ∼5 Ma earlier in North America than in Eurasia. By combining our results with existing climate model output and new sensitivity experiments, we show how these changes were influenced by ocean heat transport and atmospheric circulation patterns. We further suggest that asymmetric dispersal of large mammals between Eurasia and North America was related to the contrasting humidity regimes between the continents. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.

The Copenhagen diagnosis: updating the world on the latest climate science

The Copenhagen Diagnosis is a summary of the global warming peer reviewed science since 2007. Produced by a team of 26 scientists led by the University of New South Wales Climate Research Centre, the Diagnosis convincingly proves that the effects of global warming have gotten worse in the last three years. It is a timely update to the UN’s Intercontinental Panel on Climate Change 2007 Fourth Assessment document (IPCC AR4). The report places the blame for the century long temperature increase on human factors and says the turning point ;must come soon;. If we are to limit warming to 2 degrees above pre-industrial values, global emissions must peak by 2020 at the latest and then decline rapidly. The scientists warned that waiting for higher levels of scientific certainty could mean that some tipping points will be crossed before they are recognized. By 2050 we will effectively need to be in a post-carbon economy if we are to avoid unlivable temperatures.

Symposium summary: Towards new directions and collaborations in macroecology

news and update symposium summary Towards new directions and collaborations in macroecology 6 th Annual Meeting of the Specialist Group for Macroecology of the Ecological Society of Germany, Austria and Switzerland (GfO) – Frankfurt am Main, Germany, 29 th February–3 rd May 2012 This year, Katrin Bohning-Gaese’s group (Biodiversity and Climate Research Center, BiK-F), with support from the Senckenberg Gesellschaft fur Naturforschung and the Ecological Society of Germany, Austria and Switzerland (GfO) hosted the annual meeting of the Macroecology Specialist Group. Over 100 people attended the conference and participated in a full schedule of events including stimulating talks and posters (6 keynotes, 24 contributed talks, 18 posters), a lively panel discussions on publication in ecology and reflections of the keynote speakers on the novelty of the conference and future research directions in macroecology 1 . The conference opened with a warm welcome from Katrin Bohning-Gaese who set the stage for the meeting with an inspiring overview of macroecology research at the BiK-F. This presentation was followed by Carsten Rahbek who challenged the audience to “think big” and take on long-unresolved challenges in macroecology by embracing new tools (i.e., genomics, ancient DNA), gathering more empirical data and extending collaboration among research labs and different types of scientists. (Macro) ecologists should not be too modest in composing large research projects! The major themes of the conference included: macroecological patterns and their underlying causes; niches, distributions, communities and phylogenies under global change; advances in modelling, which included both theoretical and statistical approaches aimed at including more biological realism in models; and extinctions, conservation and new frontiers. Macroecological topics ranged from consideration of ecologically mediated diversity limits when evaluating diversification rates (Yael Kisel) to quantification of spatial and environmental effects of beta diversity in China’s woody plants (Zhiheng Wang), and evaluation of the biogeographic patterns/hypotheses of thermal melanism in European dragonflies (Dirk Zeuss). Presentations and posters under the themes of niches, distribution, communities and phylogenies under global change extended current state-of-the-art attempts to integrate these multiple types of data to address big questions in macroecology and biogeography. For instance, Sebastien Lavergne evaluated whether past rates of niche evolution influenced current demographic trends in European birds; Rafael Wuest explored how species pool definition influences inference about mechanisms (i.e., environmental filtering or biotic interactions) that structure assemblage composition; Dieter Thomas Tietze presented a poster evaluating different mechanisms causing variation in diversity gradients in Himalayan birds; and Sarah Whitmee teased apart phylogenetic relatedness and geographic location to evaluate patterns of range filling in mammals. Advances in modelling included elegant examples of new process-based Bayesian models (Florian Hartig), models integrating statistical and mechanistic models (Oliver Schweiger), combining multiple interacting species, speciation and demography (Juliano Sarmento Cabral and Miguel B. Araujo) as well as macroecological simulation studies that explored what patterns emerge when specific ecological and evolutionary processes are considered (David Orme). Finally, broad-scale process-based dynamic global vegetation models (DGVMs) were presented by Thomas Hickler who drew comparisons between these ecophy- siological and macroecological models and called for further integration of the two approaches. The last overarching topic (extinctions, 1 See program abstracts for complete details: http://www.bik-f.de/files/veranstaltungen/gfoe_macroecology/ homepage_program_full.pdf frontiers of biogeography 4.1, 2012 — © 2012 the authors; journal compilation © 2012 The International Biogeography Society

The Anisakis simplex complex off the South Shetland Islands (Antarctica): endemic populations versus introduction through migratory hosts

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 403:1-11 (2010) - DOI: https://doi.org/10.3354/meps08501 FEATURE ARTICLE The Anisakis simplex complex off the South Shetland Islands (Antarctica): endemic populations versus introduction through migratory hosts Sven Klimpel1,*, Markus W. Busch2, Thomas Kuhn1, Anika Rohde2, Harry W. Palm2 1Biodiversity and Climate Research Centre (BiK-F), Johann Wolfgang Goethe-University, Georg-Voigt-Str. 14–16, 60325 Frankfurt am Main, Germany 2Institute of Zoomorphology, Cell Biology and Parasitology, Heinrich-Heine-University Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany *Email: sklimpel@gmx.net ABSTRACT: Third-stage larvae (L3) of 2 Anisakis nematode species, A. simplex C and A. pegreffii (both A. simplex sibling species complex), were isolated from migrating myctophids around the South Shetland Islands. Gymnoscopelus nicholsi were parasitized by both nematode species, at a prevalence of 22.7% for A. simplex C and 4.0% for A. pegreffii, while Electrona carlsbergi harbored A. simplex C at a prevalence of 9.1%. The ITS-1, 5.8S, and ITS-2 regions of the nematodes were identical to specimens from Pacific Canada or California (A. simplex C) and the coast of China (A. pegreffii), confirming an extensive range of distribution for both species. The occurrence in migrating myctophids coupled with rare findings from other teleosts leads to the conclusion that both species were introduced from outside the Antarctic. Consequently, they are at their most southern range in the Southern Ocean, and an earlier molecular record of A. simplex C from the elephant seal Mirounga leonina may have detected an accidental case of infection. Delphinids, which frequently occur along South America but not in the Southern Ocean, are suggested as being the typical final hosts in the life cycles of A. simplex C and A. pegreffii. The myctophids had only few prey items within their stomachs, dominated by euphausiids, including Euphausia superba and planktonic copepods. These are common intermediate hosts for anisakid nematodes and are an important component of the Antarctic food web. Regular introduction events through migrating whales and myctophids are considered responsible for the occurrence of Anisakis infection in the high Antarctic. KEY WORDS: Anisakis simplex C · Anisakis pegreffii · South Shetland Islands · Southern Ocean (Antarctica) · Myctophids · Sibling species · Zoogeography Full text in pdf format Information about this Feature Article NextCite this article as: Klimpel S, Busch MW, Kuhn T, Rohde A, Palm HW (2010) The Anisakis simplex complex off the South Shetland Islands (Antarctica): endemic populations versus introduction through migratory hosts. Mar Ecol Prog Ser 403:1-11. https://doi.org/10.3354/meps08501 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 403. Online publication date: March 22, 2010 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2010 Inter-Research.

The biodiversity network BioFrankfurt: An innovative strategic approach to integrative research, conservation, and education

Responding to inadequate awareness of the outstanding importance of biodiversity, the BioFrankfurt network was founded in 2004 in the State of Hesse, Germany. It is presented here as a case study and may serve as a model for other parts of the world, such as the Middle East. In 2007, only about 26% of the German population were familiar with the term “Biodiversity”, and most of them only had a vague idea about its meaning. The BioFrankfurt network of institutions addressed this problem, raising public awareness and supporting research, education and conservation. A regional biodiversity education program has been developed and delivered to more than 500 schools. Since 2007, an innovative public relations campaign combines raising awareness on regional biodiversity issues with activities to improve the public image of the Frankfurt area. Because of its geographical focus, the network’s activities gained the attention of local and regional politicians and other decision makers, culminating in the joint establishment of a new Biodiversity and Climate Research Centre by BioFrankfurt member institutions. The success of current activities attracts interesting partners, resulting in challenging cooperation initiatives. The authors are convinced that the network’s concepts and activities have a great potential to profoundly enhance the notion and acceptance of biodiversity issues elsewhere.

EFFECT OF CHAMOMILE ESSENTIAL OIL ON GNOMONIA COMARI CONTROL AND STRAWBERRY FRUIT PRODUCTION UNDER ORGANIC SYSTEM

The strawberry crop is host of several pathogens and pests. The Gnomonia leaf spot (Gnomonia comari) is an emergent disease that has been occurring and limiting the production of this small fruit in the Rio Grande do Sul state, Brazil. However, there is no information about any efficient control method of this disease and also, no resistant strawberry cultivar available to organic production systems. Therefore, an experiment was carried out in order to evaluate the effect of the chamomile oil (Matricaria chamomiilla) on the control of G. comari and on yield of six strawberry cultivars ('Camarosa', 'Galexia', 'Earlibrite', 'Festival', 'Plarionfre' and 'Sabrosa'). The work was conducted at the Embrapa Temperate Climate Research Center, in Pelotas-RS, Brazil. Sixty days after the planting, the strawberries were sprayed weekly with chamomile oil at 500 ppm during 40 days. After appearing the first symptoms, the disease severity (%) of Gnomonia and some parameters which one related to fruit production were evaluated. After appearance of the first symptoms, the disease severity (%) of Gnomonia and some parameters related to fruit production were evaluated. Based on the severity values, the area under disease progress curve (Audpc) was calculated for each material tested. Thereafter, the Audpc and fruit yield data were submitted to Anova and Duncan test at 5%. It was verified that the disease severity was reduced in the 'Festival', 'Galexia' and 'Sabrosa' cultivars when plants were sprayed with chamomile oil. Although the use of chamomile oil has not affected fruit yield, 'Camarosa' and 'Galexia' showed the highest yield and 'Plarionfre' was the lowest yielder and the most susceptible to leaf spot of Gnomonia, independently of the application of chamomile essential oil.

Seasonal changes in phytoplankton growth and microzooplankton grazing at an Antarctic coastal site

AME Aquatic Microbial Ecology Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsSpecials AME 50:157-167 (2008) - DOI: https://doi.org/10.3354/ame01149 Seasonal changes in phytoplankton growth and microzooplankton grazing at an Antarctic coastal site Imojen Pearce, Andrew T. Davidson*, Simon Wright, Rick van den Enden Australian Government Antarctic Division and Antarctic Climate and Ecosystems Cooperative Research Centre, Channel Highway, Kingston, 7050 Tasmania, Australia *Corresponding author. Email: andrew.davidson@aad.gov.au ABSTRACT: Despite being a major pathway for carbon flow in aquatic systems, little is known about annual changes in microzooplankton grazing in Antarctic waters and its top-down control of phytoplankton. We determined changes in the growth and mortality of phytoplankton in near-shore waters off East Antarctica between February and November 2004 using the grazing dilution technique. Results showed large seasonal variation in the microzooplankton grazing rate and top-down control of phytoplankton. In late summer (February to March), microzooplankton consumed around 34% of primary production and 33% of the phytoplankton standing stock d–1. As sea ice formed in early April, grazing mortality increased to 762% of primary production and 72% of the phytoplankton standing stock d–1, coinciding with a rapid decline in phytoplankton biomass, cell volume and chlorophyll a concentration. In winter (late April to September), phytoplankton abundance and productivity were insufficient to sustain extensive herbivory; only 5 of the 12 winter experiments yielded microzooplankton grazing rates that were significantly different from zero. The few significant experiments showed that microheterotrophs occasionally consumed ca. 54% of the phytoplankton standing stock and >100% primary production d–1. In spring (October to November), rates of microzooplankton grazing and phytoplankton growth were highly significant but negative. Our study showed that microzooplankton contributed substantially to the termination of the summer phytoplankton bloom. Thereafter, microzooplankton grazing, though occasionally substantial, was commonly low or insignificant. Furthermore, during the aphotic Antarctic winter, negative rates of phytoplankton growth commonly exceeded those of microzooplankton grazing, suggesting that herbivory was not the principal cause of phytoplankton mortality. KEY WORDS:Antarctic · Microzooplankton · Grazing · Phytoplankton growth Full text in pdf format PreviousNextCite this article as: Pearce I, Davidson AT, Wright S, van den Enden R (2008) Seasonal changes in phytoplankton growth and microzooplankton grazing at an Antarctic coastal site. Aquat Microb Ecol 50:157-167. https://doi.org/10.3354/ame01149 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in AME Vol. 50, No. 2. Online publication date: January 31, 2008 Print ISSN: 0948-3055; Online ISSN: 1616-1564 Copyright © 2008 Inter-Research.

Balanço de carboidratos em gemas florais de dois genótipos de pereira sob condição de inverno ameno

As pereiras européias e asiáticas, cultivadas sob condições de inverno ameno, como na região Sul do Brasil, apresentam problemas de adaptação. Durante o inverno, as oscilações térmicas e o baixo acúmulo de frio têm sido referidos por alguns autores como causas do abortamento de gemas florais. O objetivo deste trabalho foi determinar o balanço de carboidratos em tecidos de gemas florais de duas cultivares de pereiras: Kieffer (P. communis x P. pyrifolia) e Housui (P. pyrifolia). Os tecidos de gemas florais e da base de gemas foram coletados mensalmente, de fevereiro a setembro de 2002, de plantas de pomar da Embrapa Clima Temperado, Pelotas-RS, coordenadas 32°51' S e 52°21'O, localizado a 230 metros de altitude. O material vegetal foi analisado separadamente quanto às concentrações de açúcares solúveis (por cromatografia gasosa) e porcentagens de amido (por espectrofotometria). Em ambas as cultivares, observou-se que a base da gema é um importante local de reserva. Ocorreram significativos aumentos de açúcares solúveis nas gemas das duas cultivares na fase que antecede a brotação. Em setembro, os açúcares solúveis totais na matéria seca (MS), nas gemas florais da cv. Housui (38,33 mg g-1), foram menores do que os observados nos tecidos da cv. Kieffer (50,39 mg g-1), cultivar melhor adaptada às condições climáticas. O açúcar-álcool sorbitol, seguido da sacarose, foi o açúcar solúvel mais abundante nos tecidos das duas cultivares.

A New Climate Research Center in Italy

The news item about the Italian Climate Research Center that will be located at the University of Lecce in Bologna (“Italy hosts a climate research center,” ScienceScope, 24 Dec. 2004, p. [2171][1]) unfortunately does not tell the whole story. The center was established without significant input from the Italian climate research community. A call for proposals was issued in 2001, and two groups responded. The review process that awarded the center to Lecce was never explained. The Ministry of the Environment simply made an informal announcement that the appropriation would go to the National Institute of Geophysics and Vulcanology, which will coordinate the center. At the moment, nothing is known about the center's programs, whether it will open to the larger climate research community, or how these programs will be funded. The initial program presented by the director suggests that the Center will be limited to oceanographers and marine ecosystem researchers in the Bologna area. Italy has allowed its National Climate Research Program to languish, and unless significant changes are made in the scope and mission of the Climate Research Center, it will be useless. First, it seems designed to produce a climate model that closely resembles those already developed elsewhere, reminiscent of Wittgenstein's philosophy that it is better to buy several copies of the same newspaper to be nearest the truth. Second, without the involvement of the larger climate academic community, the program will have no impact on higher education in the rest of the country. [1]: /lookup/doi/10.1126/science.306.5705.2171c

Italy Hosts a Climate Research Center

TRIESTE, ITALY — Italy will host a new Euro-Mediterranean Center for Climate Change Study (CMCC) to operate from the National Institute for Geophysics and Vulcanology (INGV) in Bologna, with headquarters and a dedicated supercomputer at the University of Lecce. Officials made the announcement

Estimation of bacterioplankton activity in Tasmanian coastal waters and between Tasmania and Antarctica using stains

AME Aquatic Microbial Ecology Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsSpecials AME 37:33-45 (2004) - doi:10.3354/ame037033 Estimation of bacterioplankton activity in Tasmanian coastal waters and between Tasmania and Antarctica using stains A. T. Davidson*, P. G. Thomson, K. Westwood, R. van den Enden Australian Antarctic Division, Department of the Environment and Heritage, and Antarctic Climate and EcosystemsCooperative Research Centre, Channel Highway, Kingston, Tasmania 7050, Australia *Email: andrew.davidson@aad.gov.au ABSTRACT: Various stains have recently become available that detect bacteria with compromised cell membranes and high esterase or respiratory activity. However, the validity of these stains for determining concentrations of live, dead and active marine bacteria is the subject of debate. We used BacLightTM (Molecular Probes) to stain bacteria with intact membranes green, due to the fluorescence of SYTO®9, while ‘leaky’ bacteria that were permeable to propidium iodide (PI) stained red. Bacteria with high metabolic activity were stained using 6-carboxy fluorescein diacetate (6CFDA) or 5-cyano-2,3-ditolyl tetrazolium chloride (CTC). Total bacteria concentration was determined using 4’,6 diamidino-2-phenylindole (DAPI) and BacLightTM (SYTO®9 + PI-stained bacteria). Comparison of stains in Tasmanian coastal waters showed that total concentrations of bacteria obtained using DAPI were not significantly different from those using BacLightTM at the concentrations used in our field study. Lower concentrations of BacLightTM reduced the concentration of PI-stained bacteria but not that of those stained by SYTO®9. Concentrations of metabolically active bacteria obtained using CTC and 6CFDA were equivalent to those of viable, culturable bacteria obtained using most probable number. Bacterioplankton activity in the Southern Ocean between Tasmania and East Antarctica during austral winter 1999 and summer 2001 was investigated using these stains. SYTO®9-stained cells commonly comprised <30% of total bacteria, while the remainder stained with PI. CTC- or 6CFDA-stained bacteria comprised around half of the SYTO®9-stained bacterial concentration. Significant positive correlation was observed between concentrations of total bacteria, seawater temperature (mainly due to the correlation between temperature and concentrations of PI-stained bacteria) and in situ chlorophyll fluorescence (mainly due to the correlation between in situ chlorophyll fluorescence and concentrations of highly active bacteria). Thus, bacterioplankton in the Southern Ocean are not a homogeneous community of active cells. As bacterial metabolism determines the extent to which bacteria are involved in respiration, remineralisation and the microbial loop, our findings are of major significance for understanding pelagic carbon flow and nutrient cycling in the Southern Ocean. KEY WORDS: Antarctic · Marine · Bacteria · Activity Full article in pdf format PreviousNextExport citation RSS - Facebook - Tweet - linkedIn Cited by Published in AME Vol. 37, No. 1. Online publication date: November 02, 2004 Print ISSN: 0948-3055; Online ISSN: 1616-1564 Copyright © 2004 Inter-Research.

Produção de forrageiras anuais de estação fria no litoral sul do Rio Grande do Sul

Forrageiras anuais de estação fria, Avena strigosa Schreb cv. IAPAR-61 Ibiporã, Lolium multiflorum Lam cv. Comum, Lotus subbiflorus Lag. cv. El Rincón, Avena sativa L. cv. UPF-16, Trifolium subterraneum L. cv. Woogenellup, Trifolium resupinatum L. var. resupinatum cv. Kyambro, Secale cereale L. cv. BR-1, Trifolium vesiculosum Savi cv. EMBRAPA-28 Santa Tecla e Vicia angustifolia L. foram avaliadas usando um delineamento experimental de blocos ao acaso com três repetições, no período de 1994 a 1996, na Estação Experimental Terras Baixas da EMBRAPA - Clima Temperado, Pelotas, RS, em Planossolo, unidade de mapeamento Pelotas. A área recebeu preparo convencional e adubação conforme análise do solo. Os cortes foram efetuados a cada 28 dias, sendo o primeiro 60 dias após a emergência. Os rendimentos médios anuais de MS (kg/ha•ano) e os teores médios de PB e FDN foram determinados. Houve efeito da interação entre anos e espécies. Avena strigosa IAPAR-61, L.multiflorum Comum e L.subbiflorus Rincón foram destaque, pelo alto potencial de produção de forragem, assim como pelo crecimento nos períodos outono/inverno, inverno/primavera e primavera, respectivamente. Todas as espécies avaliadas produziram forragem de alto valor nutricional, em termos dos teores de PB e FDN. Vicia angustifolia teve sempre o mais alto teor de PB e a maior produção relativa de inverno. Trifolium subterraneum Woogenellup foi a única espécie que produziu sementes viáveis suficientes para assegurar adequada regeneração natural da planta no início do segundo ano.

British Meteorological Office Spins off Climate Research Center

British Meteorological Office Spins off Climate Research Center