Alpine Tundra

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Alpine Tundra National Park Rocky Mountain Colorado National Park Service U.S. Department of the Interior Alpine Tundra WHAT IS ALPINE TUNDRA? Where mountaintops rise Arctic tundra occurs around like islands above a sea of the north pole. Alpine tundra trees lies the world of the crowns mountains that alpine tundra. John Muir reach above treeline. called it "a land of deso­ ...a world by itself lation covered with beautiful Rocky Mountain National in the sky. light." Yet this light shines Park is recognized world­ on a tapestry of living detail. wide as a Biosphere Reserve —Enos Mills Tundra lands too cold for because of the beauty and trees support over 200 kinds research value of its alpine of plants, as well as animals wild lands. Alpine tundra is from bighorn to butterflies. a sensitive indicator of such climatic changes as global Tundra is a Russian word for warming and acid rain. Over "land of no trees." 1/3 of the park is tundra. HOW FRAGILE IS IT? For 25 years after Trail That is why busy stops Ridge Road opened in 1932, along Trail Ridge Road are people had free run on the marked as Tundra Protection tundra. Repeated trampling Areas where no walking off damaged popular places. the trail is allowed. Some of these areas, fenced Elsewhere, walking on the off in 1959 for study, show tundra is permitted. But almost no sign of recovery walk with care! Step lightly, today. High winds and long without scuffing the winters make new growth surface. Step on rocks slow. Trampled places may when you can. Spread out take centuries to heal. groups to limit their impact. SNOW IN JULY? The tundra's brief summer is Average annual precipitation squeezed into only about 40 is 25 inches (64 cm), of frost-free days per year. which 65% falls as snow. Temperatures stay below freezing for over 5 months, In summer, afternoon while winter winds blow up thunderstorms with light­ to 170 mph (274 km/hr). ning, hail, and high winds Summer days seldom reach are frequent. Keep an eye 60°F (16°C). Snow may on the clouds; storms can fall any day of the year. arrive within minutes. ALPINE ADAPTATIONS Strong winds, scant soil, a Few animals live all year on short growing season, thin the tundra. Pika cut and dry air, intense sunlight, temper­ stacks of plants in summer ature extremes, and limited for their winter larder. water challenge alpine life. Ptarmigans, the only birds to winter on the tundra, grow Plants cope by hugging the feathers on the bottoms of ground and having waxy or their feet. Their toenails hairy leaves to shed wind sprout comb-like teeth that and hold water. Red work as snowshoes. Many pigments act as sunscreen. animals migrate. Marmots Roots are extensive; tundra hibernate. Some commute: plants, like icebergs, have ravens, hawks, coyotes, elk, and people visit the tundra 0% printed with biodegradable ink up to 90% of their bulk t JJron recycled paper below the surface. only for the day. THE ALPINE TUNDRA ECOSYSTEM It may look monotonous —but look again! While standing in one spot you could touch a meadow, a bog, or a rocky desert. Microclimates make the difference, as when a plant takes root where a rock shelters it from wind. How many different communities can you recognize? FELLFIELDS Literally "fields of rocks," fellfields lie on exposed slopes where winter winds blow away SNOWBED COMMUNITIES the snow. Water and soil are scarce, but lichens—crust-like A distinct community forms plants that tolerate extremes of ALPINE TURFS AND where wind piles up snow. cold and drought—can grow on MEADOWS Late-melting snow shortens the the rocks. The dominant plants growing season for plants take the shape of "cushions," Much of Rocky's alpine land is beneath it, but insulates in hugging the ground to shed KRUMMHOLZ covered with dense turfs of winter and yields a bonus of wind. As dead leaves and soil sedges and grasses. Rich soils water in spring. Blossoms of collect within a cushion plant, Alpine tundra begins where accumulated here support a the yellow snow buttercup less hardy plants may sprout in trees give up the fight against bright diversity of wildflowers, {Ranunculus adoneus) often this fertile bed. In time, cold, wind, and a too-short whose colors peak in early July. push up through the snow. invading plants may replace the growing season. At Rocky, this The largest flower on the Look for the sinuous casts of cushion, and a fellfield may happens near 11,500 feet tundra, the alpine sunflower soil left by pocket gophers become a meadow. Moss (3505 m), marked by the low, (Rydbergia grandiflora), grows tunneling under the snow. The campion [Silene acaulis) is a wind-blasted spruce or fir trees only in the Rocky Mountains. gophers eat plant roots. The common cushion plant at called krummholz ("crooked Its roots store solar energy soil they turn over makes a Rocky. Like nearly half of wood"). Many of these small from ten summers or more seedbed for flowers, which Rocky's alpine plants, it grows trees have battled over a before blooming once. Then begins a new community, the in tundra lands throughout the thousand winters. the whole plant dies. "gopher garden." northern hemisphere. .
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