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"Nitrogen (N2)-fixing microorganisms (diazotrophs) are an important source of biologically available fixed N in terrestrial and aquatic ecosystems and control the productivity of oligotrophic ocean ecosystems. We found that two major groups of unicellular N2-fixing cyanobacteria (UCYN) have distinct spatial distributions that differ from those of Trichodesmium, the N2-fixing cyanobacterium previously considered to be the most important contributor to open-ocean N2 fixation. The distributions and activity of the two UCYN groups were separated as a function of depth, temperature, and water column density structure along an 8000-kilometer transect in the South Pacific Ocean. UCYN group A can be found at high abundances at substantially higher latitudes and deeper in subsurface ocean waters than Trichodesmium. These findings have implications for the geographic extent and magnitude of basin-scale oceanic N2 fixation rates. "

"Science 25 November 2011: Vol. 334 no. 6059 pp. 1052-1053 DOI: 10.1126/science.334.6059.1052 * News Focus Adaptation to Climate Change Adaptation to Climate Change Time to Adapt to a Warming World, But Where's the Science? 1. Richard A. Kerr With dangerous global warming seemingly inevitable, users of climate information-from water utilities to international aid workers-are turning to climate scientists for guidance. But usable knowledge is in short supply. Figure View larger version: * In this page * In a new window Adapt to that. Climate will change, but decision-makers want to know how, where, and when. "CREDIT: KOOS VAN DER LENDE/NEWSCOM" DENVER, COLORADO-The people who brought us the bad news about climate change are making an effort to help us figure out what to do about it. As climate scientists have shown, continuing to spew greenhouse gases into the atmosphere will surely bring sweeping changes to the world-changes that humans will find it difficult or impossible to adapt to. But beyond general warnings, there is another sort of vital climate research to be done, speakers told 1800 attendees at a meeting here last month. And so far, they warned, researchers have delivered precious little of the essential new science. At the meeting, subtitled "Climate Research in Service to Society,"* the new buzzword was "actionable": actionable science, actionable information, actionable knowledge. "There's an urgent need for actionable climate information based on sound science," said Ghassem Asrar, director of the World Climate Research Programme, the meeting's organizer based in Geneva, Switzerland. What's needed is not simply data but processed information that an engineer sizing a storm-water pipe to serve for the next 50 years or a farmer in Uganda considering irrigating his fields can use to make better decisions in a warming world. Researchers preparing for the next international climate assessment, due in 2013, delive

perspective "The distribution of species on Earth and the interactions among them are tightly linked to historical and contemporary climate, so that global climate change will transform the world in which we live. Biological models can now credibly link recent decadal trends in field data to climate change, but predicting future impacts on biological communities is a major challenge. Attempts to move beyond general macroecological predictions of climate change impact on one hand, and observations from specific, local-scale cases, small-scale experiments, or studies of a few species on the other, raise a plethora of unanswered questions. On page 1124 of this issue, Harley (1) reports results that cast new light on how biodiversity, across different trophic levels, responds to climate change. "

"Abstract Climate change can affect organisms both directly via physiological stress and indirectly via changing relationships among species. However, we do not fully understand how changing interspecific relationships contribute to community- and ecosystem-level responses to environmental forcing. I used experiments and spatial and temporal comparisons to demonstrate that warming substantially reduces predator-free space on rocky shores. The vertical extent of mussel beds decreased by 51% in 52 years, and reproductive populations of mussels disappeared at several sites. Prey species were able to occupy a hot, extralimital site if predation pressure was experimentally reduced, and local species richness more than doubled as a result. These results suggest that anthropogenic climate change can alter interspecific interactions and produce unexpected changes in species distributions, community structure, and diversity. "

Produced by: Plastic Debris, Rivers to Sea Project Algalita and California Coastal Commission Funding provided by the State Water Resources Control Board June 2006 pdf document, 91 pages Introduction - The California Marine Debris Action Plan of 1990 - A State Mandate to Eliminate Marine Debris is Necessary - The Plastic Debris, Rivers to Sea Project - The Action Plan - The Actions Recommended in this Plan - Process and Prioritization Part I: Marine Debris - Sources, Composition, and Quantities - What is Marine Debris? - Land versus Ocean Sources - Abundance of Plastic in the Marine Environment - Quantities of Plastic Debris Increasing Significantly in Oceans - Sources and Composition of Debris Found on Beaches - Trash and Debris in Stormwater and Urban Runoff - Other Research Characterizing Trash in Urban Runoff - Distribution and Composition of Marine Debris on California's Coast Part II: Marine Debris - Impacts - Ingestion and Entanglement - Ecosystem Impacts - Debris as a Transport Mechanism for Toxics and Invasive Species - Economic Impacts Part III: Current Efforts to Address Land-Based Discharges of Marine Debris - Federal Programs and Initiatives - State Programs and Initiatives - Regional Programs and Initiatives - Local Government Programs and Initiatives - National Public Interest Groups - California Public Interest Groups and Associations - Industry Initiatives