Kana Todd M.

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Kana
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Todd M.
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  • Preprint
    Ocean urea fertilization for carbon credits poses high ecological risks
    ( 2008) Glibert, Patricia M. ; Azanza, Rhodora ; Burford, Michele ; Furuya, Ken ; Abal, Eva ; Al-Azri, Adnan ; Al-Yamani, Faiza ; Andersen, Per ; Anderson, Donald M. ; Beardall, John ; Berg, Gry M. ; Brand, Larry E. ; Bronk, Deborah ; Brookes, Justin ; Burkholder, JoAnn M. ; Cembella, Allan D. ; Cochlan, William P. ; Collier, Jackie L. ; Collos, Yves ; Diaz, Robert ; Doblin, Martina ; Drennen, Thomas ; Dyhrman, Sonya T. ; Fukuyo, Yasuwo ; Furnas, Miles ; Galloway, James ; Graneli, Edna ; Ha, Dao Viet ; Hallegraeff, Gustaaf M. ; Harrison, John A. ; Harrison, Paul J. ; Heil, Cynthia A. ; Heimann, Kirsten ; Howarth, Robert W. ; Jauzein, Cecile ; Kana, Austin A. ; Kana, Todd M. ; Kim, Hakgyoon ; Kudela, Raphael M. ; Legrand, Catherine ; Mallin, Michael ; Mulholland, Margaret R. ; Murray, Shauna A. ; O’Neil, Judith ; Pitcher, Grant C. ; Qi, Yuzao ; Rabalais, Nancy ; Raine, Robin ; Seitzinger, Sybil P. ; Salomon, Paulo S. ; Solomon, Caroline ; Stoecker, Diane K. ; Usup, Gires ; Wilson, Joanne ; Yin, Kedong ; Zhou, Mingjiang ; Zhu, Mingyuan
    The proposed plan for enrichment of the Sulu Sea, Philippines, a region of rich marine biodiversity, with thousands of tonnes of urea in order to stimulate algal blooms and sequester carbon is flawed for multiple reasons. Urea is preferentially used as a nitrogen source by some cyanobacteria and dinoflagellates, many of which are neutrally or positively buoyant. Biological pumps to the deep sea are classically leaky, and the inefficient burial of new biomass makes the estimation of a net loss of carbon from the atmosphere questionable at best. The potential for growth of toxic dinoflagellates is also high, as many grow well on urea and some even increase their toxicity when grown on urea. Many toxic dinoflagellates form cysts which can settle to the sediment and germinate in subsequent years, forming new blooms even without further fertilization. If large-scale blooms do occur, it is likely that they will contribute to hypoxia in the bottom waters upon decomposition. Lastly, urea production requires fossil fuel usage, further limiting the potential for net carbon sequestration. The environmental and economic impacts are potentially great and need to be rigorously assessed.
  • Technical Report
    The Atlantic salmon (Salmo salar) population of the Matamek River, Quebec : 1967-1984 data report
    (Woods Hole Oceanographic Institution, 1986-07) Naiman, Robert J. ; Morin, Roderick ; Caswell, Hal ; Montgomery, W. Linn ; Klopfer, Eileen ; Kana, Todd M.
    From 1967 to 1984 the Matamek Research Station, located near Sept-Iles, Quebec, was the focus of a research program on salmonid production in boreal river ecosystems. Research was conducted under the auspices of Woods Hole Oceanographic Institution and in cooperation with the Ministere du Loisir, de la Chasse et de la Peche du Quebec and representatives of several universities in Canada and the United States. One of the central activities throughout the history of the Station was monitoring of Atlantic salmon (Salmo salar) in the Matamek River. All salmon life history stages were involved, although the greatest effort was spent in estimates of parr population size at select sites and in estimates of population size, age and sex ratios of sea-run adults entering the river to spawn. Effort and methods were not consistent from year to year due to changes in program focus and improvements in techniques. Nonetheless, we believe the data represent the only long-term record for an Atlantic salmon population on the North Shore of the St. Lawrence. Heretofore, information on Atlantic salmon from the Matamek River was available only in published works or in the Matamek Annual Reports published by Woods Hole Oceanographic Institution. Because of the potential value for analyses of salmon population dynamics and life history, we have assembled the raw data, with neither analysis nor interpretation, in this report. During the period of 1980-1984, considerable effort was exerted in collecting data from original sources (field notebooks, scale envelopes, etc.) and in correcting errors in the data. We cannot, of course, guarantee complete accuracy. Nonetheless, this collection of information is the most complete and accurate compilation possible at this time. The data are presented as records for individual fish, and are ordered by date and by life history stage. We include a key to the designations of columns and to conventions used in coding data. All entries are raw data as initially recorded and coded; no analyses are available beyond those used by various individual authors in their preparation of reports or publications. While these data are made available for general use through this compilation, we request that proper acknowledgment be given the Matamek Research Program of Woods Hole Oceanographic Institution, under whose directorship this compilation was accomplished.
  • Preprint
    Methods for measuring denitrification : diverse approaches to a difficult problem
    ( 2005-07-15) Groffman, Peter M. ; Altabet, Mark A. ; Bohlke, John K. ; Butterbach-Bahl, Klaus ; David, Mark B. ; Firestone, Mary K. ; Giblin, Anne E. ; Kana, Todd M. ; Nielsen, Lars Peter ; Voytek, Mary A.
    Denitrification, the reduction of the nitrogen (N) oxides, nitrate (NO3-) and nitrite (NO2-), to the gases nitric oxide (NO), nitrous oxide (N2O) and dinitrogen (N2), is important to primary production, water quality and the chemistry and physics of the atmosphere at ecosystem, landscape, regional and global scales. Unfortunately, this process is very difficult to measure, and existing methods are problematic for different reasons in different places at different times. In this paper, we review the major approaches that have been taken to measure denitrification in terrestrial and aquatic environments and discuss the strengths, weaknesses and future prospects for the different methods. Methodological approaches covered include; 1) acetylene-based methods, 2) 15N tracers, 3) direct N2 quantification, 4) N2/Ar ratio quantification, 5) mass balance approaches, 6) stoichiometric approaches, 7) methods based on stable isotopes, 8) in situ gradients with atmospheric environmental tracers and 9) molecular approaches. Our review makes it clear that the prospects for improved quantification of denitrification vary greatly in different environments and at different scales. While current methodology allows for the production of accurate estimates of denitrification at scales relevant to water and air quality and ecosystem fertility questions in some systems (e.g., aquatic sediments, well defined aquifers), methodology for other systems, especially upland terrestrial areas, still needs development. Comparison of mass balance and stoichiometric approaches that constrain estimates of denitrification at large scales with point measurements (made using multiple methods), in multiple systems, is likely to propel more improvement in denitrification methods over the next few years.