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Referat Yellowstone National Park, Grand Canyon National park

englisch referate

englisch referate

Yellowstone National Park

Yellowstone National Park is a treasure that inspires awe in travelers from around the world. New Zealand and Iceland are known for geysers, but nowhere are there as many as in Yellowstone. At the heart of Yellowstone's past, present, and future lies volcanism. About 2 million years ago, then 1.2 million years ago, and again 600.000 years ago, huge volcanic eruptions occurred here. The latest spewed out nearly 240 cubic miles of debris. The park's present central portion collapsed, forming a 28 by 47-miles caldera, or basin - see dashed outline on large map. The magmatic heat powering those eruptions still powers the park's geysers, hot springs, fumaroles, and mud pots. The Grand Canyon of the Yellowstone gives a glimpse of Earth's interior: its waterfalls highlight the boundaries of the lava flows and thermal areas. Rugged mountains flank the park's volcanic plateau, rewarding both eye and spirit. Yellowstone's wildlife includes the American bison (buffalo), elk, grizzly and black bears etc. Vegetation types range from near-desert vegetation to sub alpine meadows and forests on Mount Washburn. Lodge pole pine covers 60 percent of the park and makes up 80 percent of the forested areas. Yellowstone would be a premier national park for its scenery of wildlife alone, but its history resonated with colourful tales of fur trappers - Jim Bridger and Osborne Russell - and explorers and surveyors, photographers and artists. William Henry Jackson's photographs and Thomas Moran's sketches influenced Congress to establish Yellowstone as the world's first national park in 1872. This national park idea has become a land-use model for many nations, and Yellowstone has evolved from a pleasuring ground and wildlife refuge to today's International Biosphere Reserve and World Heritage site, too.

Fire


Absent for hundreds of years, large fires returned to the aging forests of Yellowstone in the summer of 1988. Driven by powerful and capricious winds and fed by desert-dry fuels, small fires quickly merged into larger ones which grew into giants. By summer's end, flames had touched, in some way, nearly 800.000 acres of the Yellowstone landscape. Fires of the size and intensity of those that burned in Yellowstone in 1988 have swept through the region many times. Since the retreat of glacial ice from the plateau, nearly 12.000 years ago, massive fires have periodically cleansed, invigorated, and diversified the forests of Yellowstone. Perhaps every 300 to 350 years, they will revisit the area again, and they may be dwarfed in many magnitude by other natural events.

Landscapes are continually altered by a kaleidoscopic array of forces. Among the instruments of change are: weather, erosion, plant succession, glaciation, earthquakes, floods, human activities, and fire. Change is an immutable characteristic of the process we call nature. There is no beginning nor end to that process. One series of changes simply merges into another, often slowly and subtly, sometimes quickly and on a grand scale. Thus it was Yellowstone in 1988. Fire has increased Yellowstone's biological diversity, strengthened its ecological associations, and enhanced its human values. Yellowstone has been enriched, not impoverished, by fire.

1988 FIRE FACTS

About 793.880 acres, 36% of the park, burned within Yellowstone National Park.


Of the 249 different fires in the greater Yellowstone area, fire-fighters kept 201 (81%) from growing larger than 10 acres.


Many fires burned together, forming huge fire complexes that covered miles of steep, rugged backcountry.

Forests fires can burn at temperatures of more than 1.200 degrees Fahrenheit.


The Mink fire (in southeast Yellowstone) released enough energy to heat 4.400 homes for one year.


The last fire in the greater Yellowstone area declared out on November 19. ("Black Saturday")


On-the-ground surveys following the fires found 269 elk, 4 deer, 2 moose, 9 bison, and 6 black bears that died as a result of the fires.


Fire suppression efforts in the greater Yellowstone area cost about $120 million.


Norris Geyser Basin

Steamboat Geyser, the world's largest, erupts at irregular intervals of days to years. Echinus Geyser erupts about once per hour. Porcelain Basin is the park's hottest exposed area

Historically, the Norris area was the site of a U.S. Army outpost. The Norris Soldier Station is a link to Yellowstone's past. From 1886 to 1916, the U.S: Army administered Yellowstone National Park, and the Soldier Station is a relic of that era. Today it houses the Museum of the National Park Ranger. Exhibits tell the story of the evolution of the ranger profession from its roots in the military to the modern specialists.

Grand Canyon National park

In 1699, the Spaniard Juan Manje may have been the first to use the name Colorado to refer to the river but many years would pass before the name took hold. Explorer John Wesley Powell is credited with promoting the name Grand Canyon, which he may have borrowed from General William J. Palmer's 1868 railroad survey map. Powell and his crew endowed the canyon with many romantic and descriptive names. Geologist Clarence Dutton had a fondness for architectural and oriental terms. The topographers Francois Matthes and Richard Evans carried on the heroic nomenclature by using mythical, classical, and religious names including those from Arthurian legends. Turn of the century travelogue writers, the National Park Service, and visitors have also added a wide variety of names to the Grand Canyon's features.

By the 1890's, Grand Canyon was recognized as one of America's most scenic wonders. President Benjamin Harrison proclaimed the area the Grand Canyon Forest Preserve in 1893, but miners, stockmen, and settlers were quick to voice their opposition. In 1903, President Roosevelt visited the Grand Canyon for the first time and stated, "In the Grand Canyon, Arizona has a natural wonder which, so far as I know, is in a kind absolutely unparalleled throughout the rest of the world.in your own interests and in the interests of the country.keep this great wonder or nature as it is now.". And although Roosevelt established Grand Canyon National Monument by presidential proclamation, not until 1919 did Congress finally pass legislation to create Grand Canyon National Park.

The statistics - one -half to eighteen miles wide, a mile deep, 277 river miles long - hardly begin to convey the awesome spectacle that is the Grand Canyon. The canyon is the epitome of the geologic forces at work on the Colorado Plateau. A third of the Earth's geologic history is exposed in its walls and slopes that stair-step from boreal forests on the North Rim to Sonoran-like desert at its bottom. And while geologists have unravaled many of the intricacies of each individual layer of rock, the details of the formation of the great canyon are still shrouded in mystery. Likewise, biologists have recorded and studied the diversity of plants and animals within its walls but have barely begun to understand the interrelationships of the canyon's dynamic and complex ecosystems.

Tusayan Ruin

Excavation of the Tusayan ruin was conducted in i930 under the direction of Harold S. Gladwin and the staff of the Gila Pueblo of Globe, Arizona. They named it Tusayan following the Spanish nomenclature for the district; the exact meaning of. the word Tusayan is lost to us. The museum was established to interpret, the partially-excavated ruin. The ruin is unique in that no attempt was made at reconstruction, and portions of the ruin were deliberately left unexcavated-standard procedure today, but unheard of in 1930. The site represents the westernmost extension of the Kayenta Anasazi. It is one of the most heavily visited archeological sites in the National Park System.

Who were the Anasazi? They were the prehistoric peoples of the Four Corners region of the American Southwest, known for their pueblos and cliff dwellings, and the pottery, tools, and decorative items they produced. They occupied this region for about 1300 years. Impressive evidence that these ancient people were the ancestors of today's Pueblo peoples leads present day archeologists to call them the 'ancestral Pueblo."

The ancestral Pueblo first appear in the archeological record of the Southwest around the year AD 1. At that time they lived in pit houses, and the beautiful baskets they left behind led archeologists to use the term.' Basket maker' to describe these people and the time period from AD 500 to AD 700. Around AD 700, as they became more dependent upon agriculture, they began to construct stone pueblos to satisfy their need for permanent settlements. Archeologists classify this later period as 'Pueblo."

Compulsive builders, the ancestral Pueblo worked without cranes, bulldozers or trucks. Their masonry varied from crude shelters to magnificent multistory structures. Sites range in size from small multifamily units to villages and towns, located just about anywhere they could lay a few stones.

The largest concentration of ancestral Pueblo population was in what is now Montezuma Valley in south-western Colorado and southern Utah. This is the site we now know as Yellow- jacket, the remains of one of the largest cities of the ancestral Pueblo world. With an estimated population of 3,600 people, it boasted four plazas, twenty towers, 1,826 rooms, 166 kivas, streets with north-south alignment, and a reservoir with spillway. Chaco Canyon, in north-western New Mexico, served as a trade and distribution center for goods ranging from California abalone to Mexican parrots. Roads 25 to 40 feet (7-12 meters) wide, and 40 to 60 miles (65-100 kilometers) long radiated from Chaco.



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