sedges, mosses, lichens and grasses. There are about 400 varieties of flowers. The growing season in arctic tundra is only about 60 days long. While trees can't send their roots down, there are no trees, except for some birches in the lower latitudes. Willows do grow on some parts of the tundra but only as low carpets about 8 cm high. Most plants grow in a dense mat of roots that has developed over thousands of years. The soil is very low in nutrients and minerals, except where animal droppings fertilize the soil. Although there isn't a lot of biodiversity, only 48 species of land mammals are found on the tundra, there are a lot of each species. These consist of slightly modified shrews, hares, rodents, wolves, foxes, bears and deer. There are huge herds of reindeer in North America that feed on lichens and plants. There are also smaller herds of musk oxen. Wolves, wolverines, arctic foxes, and polar bears are the predators of the tundra
Tundra animals Reindeer Reindeer were first domesticated in Norway and northern Asia. When it was seen how valuable they were, they were brought to Alaska in 1887 and later to parts of Canada. These North American reindeer became known as caribou. Although they are called by different names, they are both considered to be a single species. Unlike deer, both the male and female have antlers. The antlers of the male are long, branched and massive, and they are a little flattened at the ends. The antlers of the female are much shorter, simpler and more slender and irregular. Their large, spreading hooves support the animal in snow in the winter and marshy tundra in the summer
drop near freezing. Their hearts also slow so much that they are barely alive. Black bears also avoid the winter by sleeping in their dens. They go into a deep sleep and only wake up several times during the winter to leave their dens. Temperate grassland- Plants are also food for animals. Most temperate grasslands are inhabited by hares, mice, and other small rodents. These animals have sharp teeth that are able to easily gnaw through grass. Some of the familiar rodents found in the North American grasslands are prairie dogs, mice, rats, and ground squirrels. Prairie dogs are cute, burrowing rodents that live in underground communities. A dominant male heads a prairie dog family. They make their home in underground burrows that consist of several chambers and entrances. Taiga - Most animals migrate to warmer climates once the cold weather begins. Some animals have adapted to life in the taiga by hibernating when temperatures drop
wonders, one of them, the Niagara Falls between lakes Erie and Ontario, which is the second biggest waterfall in the world is one of the greatest attractions in the world. About twelve million tourists come to see the beauty of the falling waters on the border between the United States of America and Canada. The Horseshoe Falls, which lie in the territory of Canada, are much bigger and have more strength than the American Falls. People can enjoy the sight and the noise of the waters from boats which take them right next to the falls. And to stay dry people receive waterproof clothing. Parts of Canada are very mountainous and the tallest mountain in Canada is the Yukon's Mount Logan, which is 6050 meters tall. Canada has many mountain ranges. In the east there are the Appalachians, Torngats and Laurentias. In the western region there are the Rocky, Coastal and Mackenzie ranges and Mount St
open areas. The cougar is territorial and persists at low population densities. Individual territory sizes depend on terrain, vegetation, and abundance of prey. A single male lion may require up to 175 square miles of territory for its home range. They prefer wild areas frequented by deer. One lion will consume about one deer per week. A lion will cover the remains of its prey and return to the kill to feed until the meat begins to turn. If you find a lion kill, don't hang around the area. The animal may still be nearby. An adult can weigh up to 200 pounds. It is the second heaviest cat in the New World, after the jaguar, and the fourth heaviest in the world, after the tiger, lion, and jaguar, although it is most closely related to smaller felines. Cougars are good climbers and can leap more than 20 feet up into a tree from a standstill. They can jump to the ground from as high as 60 feet up a tree. A single male lion may travel 25 miles a night while hunting
Erie and Ontario, is famous all over the world and attract lots of tourists. The waters of the Five Great Lakes have their outlet into the Atlantic Ocean by the St. Lawrence River, flowing mostly across the territory of Canada. Climate Almost every type of climate can be found in America, because it's very big. It's arctic in Alaska and tropical in Florida. The climate is not usually temperate, in spite of the latitude. The North American landmass heightens the variations in temperature and rainfall. Most of the country has a moist continental climate with hot summers and cold winters. There are no natural barriers either in the north or in the south. This allows dry and cold air flow in from Canada and warm, humid from the Gulf of Mexico. In this region summers are very hot and humid and rainfall decreases to the west as a result of the rain shadow created by the West Pacific range and the Sierra Nevada. The Pacific coast is
weather pattern which happens when the Southern Pacific Ocean heats up. This causes the wind direction to reserve. Instead of bringing moist air towards eastern Australia, the rain bearing clouds are blown away. An EL Nino occurs every four or five years causing droughts and bushfires. Droughts are often followed by floods. Plant Life A long time ago Australia was separated form other countries. This movement caused the difference of species, plants and animal form the other countrys. The water controls the type of vegetation in a country. The two main types of vegetation are the eucalyptus or gum trees and acacia or wattles. The eucalypts are found all over Australia. There are more than 500 varieties of gum trees in Australia. Australia is the home of some 600 species of acacia. These trees develop smaller, leathery leaves to avoid loss of water. Australia has over 155 million hectares of native forest, about 80 per cent of which are eucalypt.
Rivers The Darling River is the longest river in Australia, flowing 2,739km from northern New South Wales to its confluence with the Murray River at Wentworth, New South Wales. (Some geographers treat the Darling and the lower Murray as a single river, 3,000km long. This is largely a matter of semantics). Today the Darling is in poor health, suffering from overuse of its waters, pollution from pesticide runoff and prolonged drought, possibly the result of manmade global warming. In some years it barely flows at all. The river has a high salt content and declining water quality Deserts Deserts of Australia cover a large portion of the land in Australia. Most of the deserts lie in the central and northwestern part of the country. The Great Victoria Desert is a barren, arid and sparsely populated desert ecoregion in southern Australia. It falls inside the states of South Australia and Western Australia and consists of many small sandhills, grasslands and salt lakes
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