"GRAND CANYON NATIONAL PARK, Ariz. -- From the rim, the Grand Canyon, 15 miles wide at its most expansive and a mile deep, looks like one of the wildest, most timeless places on earth. Ponderosa pines and juniper trees girdle its plateaus, giving way to canyon walls of ancient sandstone, shale and granite, chiseled over millennia by the Colorado River below, wending through the canyon's depths along the same general course it has followed for thousands of years.
But a closer look reveals a canyon ecosystem that has been deeply altered by human forces. And today, the park is facing an unprecedented convergence of threats, the long-term effects of which are largely unknown."
April Reese reports for Greenwire April 19, 2010.
Source: Greenwire, 04/21/2010
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