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Scientists devise new method to give 'most robust' estimate of Maasai Mara lion numbers

Scientists based at Oxford University have created a new method for counting lions that they say is the most robust yet devised.Using the Maasai Mara National Reserve and surrounding conservancies in Kenya as a case study, they estimate there to be 420 lions over the age of one in this key territory. At almost 17 lions per 100 square kilometres, that represents one of the highest densities anywhere in Africa.

Sea ice hit record lows in November

Unusually high air temperatures and a warm ocean have led to a record low Arctic sea ice extent for November, according to scientists at the National Snow and Ice Data Center (NSIDC) at the University of Colorado Boulder. In the Southern Hemisphere, Antarctic sea ice extent also hit a record low for the month, caused by moderately warm temperatures and a rapid shift in circumpolar winds.“It looks like a triple whammy—a warm ocean, a warm atmosphere, and a wind pattern all working against the ice in the Arctic,” said NSIDC director Mark Serreze.

New Technology Helps Pinpoint Sources of Water Contamination

Berkeley Lab develops better method of environmental monitoring using the PhyloChip, finds surprising results in Russian River watershedWhen the local water management agency closes your favorite beach due to unhealthy water quality, how reliable are the tests they base their decisions on? As it turns out, those tests, as well as the standards behind them, have not been updated in decades. Now scientists from Lawrence Berkeley National Laboratory (Berkeley Lab) have developed a highly accurate, DNA-based method to detect and distinguish sources of microbial contamination in water.

Greenhouse gas-monitoring aircraft keep tabs on the Amazon's rising methane levels

Research led by the National Centre of Earth Observation at the University of Leicester is going to new heights in the atmosphere to get a better handle on methane emitted from wetlands in the Amazon.Using small aircraft flying in an upward spiral and collecting samples of the air, the team has measured the levels of methane in the atmosphere over the Amazon basin in unprecedented detail.In the process they've shown the value of satellite measurements of methane for the region, paving the way for research that will keep better tabs on the greenhouse gas. 

Perfluorinated compounds found in African crocodiles, American alligators

American alligators and South African crocodiles populate waterways a third of the globe apart, and yet both have detectable levels of long-lived industrial and household compounds for nonstick coatings in their blood, according to two studies from researchers at the Hollings Marine Laboratory in Charleston, South Carolina, and its affiliated institutions, which include the National Institute of Standards and Technology.Production of some compounds in this family of environmentally persistent chemicals–associated with liver toxicity, reduced fertility and a variety of other health problems in studies of people and animals–has been phased out in the United States and many other nations. Yet all blood plasma samples drawn from 125 American alligators across 12 sites in Florida and South Carolina contained at least six of the 15 perfluorinated alkyl acids (PFAAs) that were tracked in the alligator study.

Urbanization affects diets of butterflies

A study led by researchers from the National University of Singapore (NUS) revealed that most tropical butterflies feed on a variety of flower types, but those that are 'picky' about their flower diets tend to prefer native plants and are more dependent on forests. These 'picky' butterflies also have wings that are more conspicuous and shorter proboscis. The reduction in native plants due to urbanisation affects the diet of such butterflies, and researchers suggest that intervention may be needed to manage their preferred flower resources.

Drought conditions slow the growth of Douglas fir trees across the West

Whether growing along the rim of the Grand Canyon or living in the mist with California's coastal redwoods, Douglas fir trees are consistently sensitive to drought conditions that occur throughout the species' range in the United States, according to a study led by a researcher at the University of California, Davis.The study, published Aug. 8 in the journalProceedings of the National Academy of Sciences, provides direct evidence of the negative impact of water stress on forest ecosystems. It also pinpointed which conditions are causing low growth among Douglas fir trees.

Trees' surprising role in the boreal water cycle quantified

Approximately 25 to 50 percent of a living tree is made up of water, depending on the species and time of year. The water stored in trees has previously been considered just a minor part of the water cycle, but a new study by University of Alaska Fairbanks scientists shows otherwise.Research published this week in Nature Scientific Reports is the first to show that the uptake of snowmelt water by deciduous trees represents a large and previously overlooked aspect of the water balance in boreal watersheds. The study was led by Jessica Young-Robertson, who worked with other scientists from the National Weather Service and UAF's International Arctic Research Center and Geophysical Institute.

Whales dine with their friends of the same species

For a few weeks in early fall, Georges Bank — a vast North Atlantic fishery off the coast of Cape Cod — teems with billions of herring that take over the region to spawn. The seasonal arrival of the herring also attracts predators to the shallow banks, including many species of whales.Now researchers from MIT, Northeastern University, the Institute of Marine Research in Norway, and the National Oceanic and Atmospheric Administration, have found that as multiple species of whales feast on herring, they tend to stick with their own kind, establishing species-specific feeding centers along the 150-mile length of Georges Bank. The team’s results are published today in the journal Nature.

How Modular Construction is Keeping Waste Out of U.S. Landfills

When we think about the overflow of our nation’s landfills, we probably picture limiting our food waste; recycling plastics, glass and paper; and keeping out potentially harmful hazardous waste. What we probably don’t consider is one of the largest sources of waste generation, construction and demolition (C&D) waste.  It is estimated that anywhere from 25 to 40 percent of the national solid waste stream is building-related waste, with only 20 percent of C&D waste being recycled.