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"USC researcher experiments with changing ocean chemistry Jan. 19, 2011 | Molly Peterson | KPCC In his lab, USC's Dave Hutchins is simulating possible future atmospheres and temperatures for the Earth. He says he's trying to figure out how tiny organisms that form the base of the food web will react to a more carbon-intense ocean. Burning fossil fuels doesn't just put more carbon into the atmosphere and help warm the climate. It's also changing the chemistry of sea water. KPCC's Molly Peterson visits a University of Southern California researcher who studies the consequences of a more corrosive ocean. Tailpipes and refineries and smokestacks as far as the eye can see in Los Angeles symbolize the way people change the planet's climate. They remind Dave Hutchins that the ocean's changing too. Hutchins teaches marine biology at USC. He says about a third of all the carbon, or CO2, that people have pushed into earth's atmosphere ends up in sea water - "which is a good thing for us because if the ocean hadn't taken up that CO2 the greenhouse effect would be far more advanced than it is." He smiles. Hutchins says that carbon is probably not so good for the ocean. "The more carbon dioxide that enters the ocean the more acidic the ocean gets." On the pH scale, smaller numbers represent more acidity. The Monterey Bay Aquarium Research Institute estimates we've pumped 500 million tons of carbon into the world's oceans. Dave Hutchins at USC says that carbon has already lowered the pH value for sea water. "By the end of this century we are going to have increased the amount of acid in the ocean by maybe 200 percent over natural pre-industrial levels," he says. "So we are driving the chemistry of the ocean into new territory - into areas that it has never seen." Hutchins is one of dozens of scientists who study the ripples of that new chemistry into the marine ecosystem. Now for an aside. I make bubbly water at home with a soda machine, and to do that, I pump ca

Science 3 February 2012: Vol. 335 no. 6068 pp. 520-521 DOI: 10.1126/science.335.6068.520 News Focus Ecology Rebuilding Wetlands by Managing the Muddy Mississippi Carolyn Gramling Coastal managers and scientists have struggled to find ways to restore water flow through the wetlands of the Mississippi delta and bring back the sediment, supply of which has been cut in half by humanmade river channels, levees, and dams intended to control the river and save coastal communities from flooding. The U.S. Army Corps of Engineers opened the Morganza spillway during the 2011 Mississippi River floods to divert floodwaters, which offered a rare opportunity to conduct a large-scale natural experiment in real time. The floodwaters did carry enough sediment to help rebuild the wetlands, but that material didn't always stay where it could do the most good. However, researchers gained valuable insights-including ideas about how spillway design can help produce more targeted sediment deposits, and what volume of flow through the spillways might be required for effective wetland rebuilding.

"Abstract The Phanerozoic fossil record of marine animal diversity covaries with the amount of marine sedimentary rock. The extent to which this covariation reflects a geologically controlled sampling bias remains unknown. We show that Phanerozoic records of seawater chemistry and continental flooding contain information on the diversity of marine animals that is independent of sedimentary rock quantity and sampling. Interrelationships among variables suggest long-term interactions among continental flooding, sulfur and carbon cycling, and macroevolution. Thus, mutual responses to interacting Earth systems, not sampling biases, explain much of the observed covariation between Phanerozoic patterns of sedimentation and fossil biodiversity. Linkages between biodiversity and environmental records likely reflect complex biotic responses to changing ocean redox conditions and long-term sea-level fluctuations driven by plate tectonics. "

California Department of Toxic Substances Control Office of Pollution Prevention and Technology

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

"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. "

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