Word: sediments
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...effective wildlife habitat for murrelets, Pacific giant salamanders and the spotted owls that loggers love to hate. In particular, they offer little protection for coho salmon, listed as threatened in the state. Salmon need cool, shaded, clear streams for spawning. Aggressive, steep-slope logging cuts shade and pours down sediment. This is no secret, but the state has not enforced regulations to protect salmon streams, and the new Headwaters legislation, say critics, stipulates buffer zones too narrow to be effective...
...Jobs notes, "Look, you work on a technical product, and if you're really lucky, it ships. If you're really, really lucky, it's a hit and lasts a year. If you're in the pantheon of products it lasts a decade, then it rapidly becomes a sediment layer on which the next layer of technology is built. I don't think you'll be able to boot up any computer today in 20 years...
ACTIVATED-CARBON FILTRATION. These systems are the most popular and the most effective in reducing so-called aesthetic contaminants like chlorine and sediment. Filters made of carbon in solid block form, as opposed to granules, are also highly effective in reducing lead. Systems range from inexpensive pour-through carafes to filters that are mounted on faucets, on countertops or under the sink. Cost...
...mechanism, speculates Knoll, could have been erosion from steep mountain slopes. Over time, he notes, tons of sediment and rock that poured into the sea could have buried algal remains that fell to the sea floor. In addition, he says, rifting continents very likely changed the geometry of ocean basins so that water could not circulate as vigorously as before. The organic carbon that fell to the sea floor, then, would have stayed there, never cycling back to the ocean surface and into the atmosphere. As levels of atmospheric carbon dioxide dropped, the earth would have cooled. Sure enough, says...
...drive north of Nairobi along the shores of Lake Turkana in the East African Rift Valley. An 1,800-mile-long gash in the surface of the earth, the Rift has yielded many important clues to early human history, because of its unique geology. Layers of sediment preserved animal specimens, while the volcanic eruptions that periodically shook the valley produced ash and lava whose radioactive elements make the fossils easy to date. Probably the most famous inhabitant of the valley was the diminutive creature known as Lucy (Australopithecus afarensis), whose fossil skeleton was discovered in 1974 and who lived more...