Earth

With their sedentary lifestyles and filter-feeding habits, clams have been silent witnesses to the changes that humans have inflicted upon their waters. These clams are silent no more, as Dr. Ruth H. Carmichael of the Dauphin Island Sea Lab and her colleagues have reported in their recent paper in the prestigious journal Aquatic Biology. Using stable isotope techniques, Carmichael demonstrated it is possible to identify and trace wastewater inputs to estuaries and coastal food webs by studying the organic matrix in the shell of the hard clam Mercenaria mercenaria.

Converting forests or fields to biofuel crops can increase or decrease greenhouse gas emissions, depending on where – and which – biofuel crops are used, University of Illinois researchers report this month.

The researchers analyzed data from dozens of studies to determine how planting new biofuel crops can influence the carbon content of the soil. Their findings appear this month in the journal Global Change Biology Bioenergy.

The Arctic is undergoing rapid transformation due to climate change, pollution and human activity. ESA's ERS and Envisat satellites have been providing satellite data of the region for the last 17 years. These long term data sets in combination with ESA's future missions will be key in implementing the newly adopted European Commission policy called 'The European Union and the Arctic Region'.

African cities are growing faster than anywhere else in the world. This is having a major impact, but few ecologists are studying the urban environment and effect of cities on rural areas. One of the most important ecological changes in Africa's history is being over-looked.

Starch grains preserved on human teeth reveal that ancient Peruvians ate a variety of cultivated crops including squash, beans, peanuts and the fruit of cultivated pacay trees. This finding by Dolores Piperno, staff scientist at the Smithsonian Tropical Research Institute and the National Museum of Natural History, and Tom Dillehay, professor of archaeology at Vanderbilt University, sets the date of the earliest human consumption of beans and pacay back by more than 2,000 years and indicates that New World people were committed farmers earlier than previously thought.

GAINESVILLE, Fla. — The University of Florida, keeper of the world's shark attack records, is also now overseeing a national records collection for another toothy marine predator: the sawfish.

Distinguished by a long rostrum or "saw" that makes it a popular curio item and gives it its name, the sawfish has become a historical and cultural icon that is rapidly disappearing, said George Burgess, a UF ichthyologist and curator of both the International Shark Attack File and the newly expanded National Sawfish Encounter Database.

Boulder, CO, USA – The December Geosphere, The Geological Society of America's e-journal, is now online. Topics include detailed data integration from multiple fields, including tectonics, oceanography, sedimentology, and paleontology, to study the southwestern U.S. climate 17 million years ago to 6 million years ago; sedimentation in a piggyback basin; Angel Lake orthogneiss in the East Humboldt Range, Nevada; and a study of the South Balkan extensional system within southern Bulgaria, Macedonia, eastern Albania, northern Greece, and northwestern Turkey.

Microorganisms in rivers and streams play a crucial role in the global carbon cycle that has not previously been considered. Freshwater ecologist Dr. Tom Battin, of the University of Vienna, told a COST ESF Frontiers of Science conference in October that our understanding of how rivers and streams deal with organic carbon has changed radically.

Microorganisms such as bacteria and single celled algae in rivers and streams decompose organic matter as it flows downstream. They convert the carbon it contains into carbon dioxide, which is then released to the atmosphere.

The planet's present day greenhouse scourge, carbon dioxide, may have played a vital role in helping ancient Earth to escape from complete glaciation, say scientists in a paper published online today.

In their review for Nature Geoscience, UK scientists claim that the Earth never froze over completely during the Cryogenian Period, about 840 to 635 million years ago.

WASHINGTON DC, December 1, 2008 -- Keeping tropical rain forests intact is a better way to combat climate change than replacing them with biofuel plantations, a study in the journal Conservation Biology finds.