There is a great deal of exposed rock in and around the Grand Canyon. Much of of that rock is covered by lichens.
A lichen is what one could call a simple biological “community” because it is made up of at least two mutually-dependent organisms. In a lichen, some type of fungi is found along with green algae and /or cyanobacteria.
A lichen community is therefore stronger than either fungus or algae alone. Here's how they help each other out; the green algae uses the photosynthesis process to produce food for the fungus, while the fungus protects the algae from the elements and extracts nutrients from the rocks and soil.
Lichens usually colonize north-facing surfaces since exposure to the sun's heat and radiation is less on north-facing rocks and slopes. Lichens may also grow on healthy, mature cryptobiotic soil crust, and occasionally on live or dead plant material. Many species of lichen are found within Grand Canyon National Park.
Lichens are well adapted to arid climates since they can produce food at any temperature above freezing. Another thing that makes lichens good desert survivors is that they can soak up more than their weight in water. Fungi and green algae are non-vasular plants (without roots and stems) so they can directly soak up dew and rain into their cells.
Related Information
Canyon Sketches Vol 02 - April 2008
Volunteers Help Control Invasive Plants Invasive plants such as Sahara mustard pose a serious ecological threat to Grand Canyon. Volunteers have made important contributions towards controlling this aggressive invader over the last few years. Volunteer trips with Science and Resource Management’s vegetation program are fun and educational and give people who love Grand Canyon the opportunity to help preserve park resources.
Canyon Sketches Vol 05 - August 2008 Park Biologists Conserve Rare Plant
Plant biologists identified several populations of Tusayan flameflower (Phemeranthus validulus) in areas that will be impacted by the construction of parking lots at Canyon View Information Plaza. In order to conserve this rare Grand Canyon species, they recently salvaged plants from construction zones and transplanted them in suitable habitat nearby.
Did You Know?
During the summer months temperatures within the Grand Canyon are extremely high. Plan your day so you are not hiking between the hours of 10am and 4pm. Take a break near shade and water to avoid the worst heat of day. Enjoy a predawn start and a late afternoon finish.
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