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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Natural History

In many locations, people interested in natural history, which includes all information about the natural world, focus their attention on the plants and animals, and think of the geology as a backdrop. In the Grand Canyon the geologic features strike even the most ardent biologists. Not only is the geology visually grabbing, but also it is quickly apparent what a strong influence the geology, from rock type to topographic features, has on where plants and animals live. Consider for instance that different rock layers decompose to form soils with different nutrients and textures, affecting water-holding capacity and water availability, and therefore plant cover.

Even more apparent to a casual hiker, consider how variable the topography can be. For instance, some rock layers erode easily forming slopes, while others are cliffs, each creating unique habitats required and tolerated by different species. Where a north-facing cliff and gentler topography meet is a small patch of real estate that remains shadier and cooler, allowing a unique collection of species to establish. Rock formations with alternating layers of sandstone and shale, may create small platforms of soil underlain by fractured rock—if a tree takes root, it might find moister soil deep down. A wash that carries water occasionally will host different species than the dry terraces to either side. This variation in physical features creates patchiness in resources and in turn leads to a surprising diversity in plants and animals. As you explore the inner canyon, consider the interactions between the physical and biological worlds.