Читать книгу One Best Hike: Grand Canyon. Everything You Need to Know to Successfully Hike from the Rim to the River—and Back онлайн

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Riparian: This community exists only in locations with permanent water, such as along the banks of the Colorado River and its side canyons. The availability of water means that large trees and dense thickets of shrubs and herbs are able to grow in these locations. The dominant species include Fremont cottonwood, coyote willow, seepwillow, saltcedar, honey mesquite, and catclaw acacia. The riparian vegetation along the Colorado River has changed significantly since the completion of the Glen Canyon Dam in 1964; water flows are now restricted and the river no longer floods as severely, a process that once scoured the vegetation along the banks and deposited vast quantities of sediment. Beginning in 1996 the Bureau of Reclamation has three times released higher flows from Glen Canyon Dam to replicate historic flooding. The largest flow occurred in March 2008, when they released twice the usual flow of water. Preliminary research indicates that this flood effectively mimicked natural floods, creating large sandbanks, reducing the establishment of nonnative plants, and creating backwater environments.