Biodiversity Is commercial fishing altering ocean food webs?

Posted on May 15, 2013 by Bob Berwyn

New study shows how the diet of pelagic birds has changed over time

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Studying isotopes in the bones of pelagic seabirds helped researchers track changes in thePacific ocean food chain. Bob Berwyn photo.

By Summit Voice

FRISCO — Some in-depth biological detective work suggests there have been drastic changes in open-ocean food webs since the onset of industrial fishing, with potentially significant implications for threatened seabirds.

The key to detecting the changes was analyzing the bones of Hawaiian petrels. The crow-sized oceanic birds range widely over the northeast Pacific, and their diets integrate food webs from that vast area. What the petrels have eaten is recorded in the chemistry of their bones. By extracting protein from bones and feathers and studying stable isotopes of carbon and nitrogen in the protein, the scientists were able to assess the birds’ diet and how it changed over centuries. (more…)

Filed under: biodiversity, endangered species, Environment, Marine biology, ocean conservation | Tagged: , , , , | Leave a Comment »

Will global warming boost biodiversity?

Posted on September 4, 2012 by Bob Berwyn

What will inexorable warming mean for biodiversity.

Only in the long run; short-term outlook is for species loss

By Summit Voice

FRISCO — An analysis of fossil and geological records going back 540 million years suggests that, in general, the Earth’s biodiversity has increased during interglacial warm periods — but only in the long run, depending on the evolution of species over millions of years.

Short-term, the current warming trend is likely to cut biodiversity, in part because of the pace of climbing temperatures, according to researchers from the universities of York, Glasgow and Leeds. (more…)

Filed under: climate and weather, endangered species, Environment, global warming | Tagged: , , , | Leave a Comment »

Archaeologists discover largest Maya dam at Tikal

Posted on August 13, 2012 by Bob Berwyn

Temple at Tikal, Guatemala. Photo courtesy Raymond Ostertag.

Ancient earthworks helped ensure sustainable management of resources in challenging environment

By Summit Voice

SUMMIT COUNTY — Archaeologists have long known that the Maya were sophisticated engineers, but new excavations at Tikal, Guatemala show the amazing extent to which they were able to manipulate the environment to their advantage, including construction of 260-foot dam that stored up to 20 million gallons of water.

That dam – constructed from cut stone, rubble and earth – stood about 33 feet high and held about 20 million gallons of water in a man-made reservoir.

The research, conducted by a multi-university team led by the University of Cincinnati, helps explain how the Maya conserved and used their natural resources to support a populous, highly complex society for over 1,500 years despite environmental challenges, including periodic drought. (more…)

Filed under: Archaeology, Uncategorized | Tagged: , , , , , , , | Leave a Comment »

Study warns of ‘unsustainable’ groundwater depletion in California’s Central Valley and the central High Plains

Posted on May 30, 2012 by Bob Berwyn

California’s Central Valley aquifers. MAP COURTESY USGS.

Southern High Plains could run out of groundwater in the next few decades

By Summit Voice

SUMMIT COUNTY — University of Texas researchers didn’t mince words after studying how irrigated agriculture is depleting groundwater in some of the country’s semi-arid regions.

“Basically irrigated agriculture in much of the southern High Plains is unsustainable,” said said Bridget Scanlon, senior research scientist at The University of Texas at Austin’s Bureau of Economic Geology.

After taking a close look at irrigation practices and groundwater levels in California’s Central Valley and in the High Plains, region, the scientists concluded that the nation’s food supply could be vulnerable to groundwater depletion. They hope the data will enable more sustainable use of water. (more…)

Filed under: agriculture, Environment, Summit County news, water | Tagged: , , , , , | 2 Comments »

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