Tag Archives: algae

A New Way of Looking at Photosystem II

By Guest PostJune 14, 2012Sciencealgae, angstroms, bacteria, berkeley lab, carbon dioxide, catalytic cycle, critical formation, cryogenic freezing, electrochemical energy, electrons, femtosecond timescale, femtosecond x ray pulses, green, green plants, hydrogen atom, hydrogen ions, jan kern, junko yano, knowledge, lcls, microcrystals, nicholas sauter, oxidation states, oxygen molecules, paul adams, photooxidation, photosynthesis, photosystem ii, protein crystallography, proteins, protons, renewable energy, resolution, slac, solar energy, synchrotron radiation, terabytes of data, uwe bergmann, vittal yachandra, water, xray diffraction, xrays

Berkeley Lab and SLAC Researchers Study Key Protein Complex Crucial to Photosynthesis

Future prospects for clean, green, renewable energy may hinge upon our ability to mimic and improve upon photosynthesis – the process by which green plants, algae and some bacteria convert solar energy into electrochemical energy. An artificial version of photosynthesis, for example, could use sunlight to produce liquid fuels from nothing more than carbon dioxide and water. First, however, scientists need a better understanding of how a large complex of proteins, called photosystem II, is able to split water molecules into oxygen, electrons and hydrogen ions (protons). A new road to reaching this understanding has now been opened by an international team of researchers, led by scientists at the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) and SLAC National Accelerator Laboratory.

Using ultrafast, intensely bright pulses of X-rays from SLAC’s Linac Coherent Light Source (LCLS), the research team produced the first ever images at room temperature of microcrystals of the photosystem II complex. Previous imaging studies, using X-rays generated via synchrotron radiation sources, required cryogenic freezing, which alters the samples. Also, to catalyze its reactions, photosystem II relies upon an enzyme that contains a manganese-calcium cluster that is highly sensitive to radiation. With the high-intensity femtosecond X-ray pulses of the LCLS, the research team was able to record intact images of these clusters before the radiation destroyed them. (more…)

Ecosystem Effects of Biodiversity Loss Could Rival Impacts of Climate Change, Pollution

By Guest PostMay 10, 2012Environment, Natureacid deposition, air pollution, algae, bacteria, biodiversity loss, biological diversity, bradley cardinale, california, canada, climate change, david hooper, ecosystem, environmental change, environmental stress, environmental stressors, extinction, forests, fungi, global warming, henry gholz, impact, leslie gonzalez, nutrient pollution, oxygen, ozone pollution, pollution, san josé, serpentine grasslands, Sweden, united states, university of michigan

ANN ARBOR, Mich.— Loss of biodiversity appears to impact ecosystems as much as climate change, pollution and other major forms of environmental stress, according to a new study from an international research team.

The study is the first comprehensive effort to directly compare the impacts of biological diversity loss to the anticipated effects of a host of other human-caused environmental changes.

The results highlight the need for stronger local, national and international efforts to protect biodiversity and the benefits it provides, according to the researchers, who are based at nine institutions in the United States, Canada and Sweden. (more…)

Plastic Pollution

By Guest PostMay 2, 2012Environmentalgae, bacteria, dylan meyer, environmental group, factor, giora proskurowski, historical weather data, kara lavendar law, liver function, mathematical model, model, north atlantic expedition, ocean, pacific garbage patch, plastic marine debris, plastic particles, plastic pollution, pollutant, recipe, skye moret ferguson, teresa messmore, tobias kukulka, university of delaware, university of washington, wind

Wind pushes plastics deeper into oceans, driving trash estimates up

Decades of research into how much plastic litters the sea may have only skimmed the surface. A new study reveals that wind drives confetti-sized pieces of plastic debris deeper underwater than previously believed, more than doubling earlier estimates of the pollutant’s presence in oceans.

“In windy conditions the traditional approach to measuring plastic marine debris captures only a small fraction of plastic pieces,” said Tobias Kukulka, assistant professor of physical ocean science and engineering in the University of Delaware’s College of Earth, Ocean, and Environment. “Our study helps to better understand how much plastic there is and where, as well as the complexity of the ocean dynamics at work.” (more…)

Sailing in a Sea of Microbes

By Guest PostMarch 4, 2012Sciencealgae, Arctic, atmospheric chemistry, bacteria, biogeochemical cycles, biomass, carbon dioxide, Chile, climate, daniel stolte, easter island, Environment, food production, genome, Germany, global warming, grassroots initiative, greenhouse gas, matt sullivan, melissa duhaime, microbe, ocean water, oceans, oxygen production, pacific ocean, research vessel, saguaro cacti, sequence, tara oceans, ua, university of arizona, wolves, world of viruses, world of webs

Researchers led by Matt Sullivan at the UA are among the first to dive into the world of viruses drifting through the world’s oceans.

Surrounded by the deep blue of the Pacific Ocean stretching from horizon to horizon, a lonely dot is glinting in the sun. It is the aluminum hull of a sailboat, a 118-foot schooner with white sails billowing from two masts.

On the deck, crewmembers and scientists are milling about. Commands are flying back and forth, and soon a strange contraption consisting of tubes clustered around an array of sensors dangling from a crane is lowered into the water, until it disappears in the clear blue depths. (more…)

Yale-led Team Finds CO2 Levels Plunged as Antarctica Froze

By Guest PostDecember 3, 2011Environmentalgae, atmosphere, carbon dioxide levels, climate transition, co2 and climate change, critical condition, cryosphere, earth, eocene epoch, eocene to oligocene, freezing of antarctica, fundamental link, geochemist, global climate change, global cooling, greenhouse gases, ice sheets, icing of antarctica, mark pagani, matthew huber, molecules, oligocene, polar ice caps, robert m deconto, sea level, temperatures, yale university, zhonghui liu

A Yale University-led research team has found evidence that carbon dioxide levels in Earth’s atmosphere plunged prior to and during the initial icing of Antarctica, about 34 million years ago. The new findings provide further evidence of atmospheric carbon dioxide’s role as a major trigger of global climate change.

“CO2 is tracking global cooling at that time,” said Yale geochemist Mark Pagani, lead author of a paper published online Dec. 1 in the journal Science. “It’s important to demonstrate that there are obvious linkages between CO2 and climate change. It’s one more piece of evidence that CO2 is a primary lever on climate.” (more…)

‘Undersea Methane Could be Contributor to Increased Ocean Acidity’

By Guest PostDecember 7, 2010Environmentacidity, algae, bacteria, bottom of the ocean, carbon dioxide, chris osburn, CO2, cold seeps, degradation, dissolved organic carbon, doc, fluids, marine science, methane, methane-derived doc, microbial processing, ocean, ocean acidification, oceanic microorganisms, pacific ocean, phytoplankton, seawater, sediments, undersea, undersea ecosystems

A North Carolina State University researcher is part of a team which has found that methane from “cold seeps” – undersea areas where fluids bubble up through sediments at the bottom of the ocean – could be contributing to the oceans’ increasing acidity and stressing already delicate undersea ecosystems.

Oceanic microorganisms and bacteria survive by consuming dissolved organic carbon, or DOC. A byproduct of this consumption is CO2 – carbon dioxide – which, in large enough concentrations, makes seawater more acidic. (more…)

Listing of Rare Hawaiian Coral Species Called into Question

By Guest PostDecember 3, 2010Naturealgae, blue rice coral, coral biodiversity, coral reef, coral skeleton, discovery, diverse habitats, ecosystems, endemic, genetic groups, hawaii institute of marine biology, hawaiian reef coral, hawaiian species, himb, invertebrate species, m dilatata, m flabellata, m patula, marine animals, montipora, planet, rob toonen, sandpaper rice coral, zac forsman

Close up of Montipora patula (Sandpaper Rice Coral). Image credit: Zac Forsman

Researchers at the Hawai‘i Institute of Marine Biology (HIMB), an organized research unit in the University of Hawai‘i at Mānoa’s School of Ocean and Earth Science and Technology have made a remarkable new discovery.

Coral reef ecosystems are one of the most diverse habitats on the planet, providing habitat for a wide variety of marine animals. Unfortunately, coral reefs and their associated fish, algae, and invertebrate species are in worldwide decline. In 2009, 83 rare corals were petitioned to be listed under the United States Endangered Species Act. The National Oceanic and Atmospheric Administration (NOAA) National Marine Fisheries Service is currently reviewing the status of the coral on the petition. If the listing is granted, it will afford higher protection and designate critical habitat for these corals. But are all the ‘species’ on this list really species?

A challenge to the evaluation is that coral “species” definitions are presently based on the coral skeleton, which can be so variable that it is often difficult to distinguish between groups. All 83 species on the petition can be found in the United States with 9 corals found in Hawai‘i. Identifying which of the corals on this list are endemic (unique to each region), rare, or at risk of extinction, may prove difficult because it is not clear which corals interbreed. (more…)

Coral Algae Discovered in Black Corals at Never Before Seen Depths

By Guest PostOctober 25, 2010Naturealgae, black corals, coral, coral biology, daniel wagner, discovery, habitats, hawaii institute of marine biology, himb, jewelry industry, photosynthetic algae, photosynthetic symbiotic algae, shallow water reef building corals, symbiodinium, tropical, university of hawaii at manoa, zooxanthellae

Hawaiian Black Coral. Image credit: Daniel Wagner, HIMB

When most people envision coral, they typically think of shallow-water reef-building corals found along beaches and tropical nearshore habitats. These “typical” corals are dependent upon photosynthetic algae (also known as Symbiodinium or zooxanthellae) found in their tissues to obtain nutrients to live off of.

In deeper less known waters, closely related black corals were considered to be void of these algae because of the light shortage to support photosynthesis. In fact, all black corals were considered to lack Symbiodinium (algae), because they are typically found at great depths where light levels are very low. (more…)