§ 40. Natural areas
Remember what the law is subject to location natural areas.
Reach natural areas in North America has features. In the north of the mainland are under zoning law, change in direction from north to south, and in central and southern parts - from east to west. The main reason for this placement - the influence of terrain (Cordillera) to the distribution of moisture on the mainland.
Arctic ZONE Desert. It northern natural area of the globe. It includes Greenland and the Canadian Arctic archipelago. The climate there Arctic is very hard. The islands are covered with snow and ice. Where there is snow in summer time to melt, the stony surface Mosses and lichens grow. Lives of most animals - polar bear, seals, walruses, birds - is concerned with the sea. There are also lemming - small rodent with fluffy fur, which is held during the winter snow proryvayuchy many moves. In his hunt polar blue fox and wolf.
Fig. In the Arctic wilderness
The largest carnivorous is the Earth's polar bear, which reaches 2.5 m length and 450 kg weight. He swims well and, unlike his brown relative, an active lifestyle all year round. Thick fur, which covers even soles of feet, and a layer of fat at 10 cm, to protect the bear from the cold. Animal included in the Red Book.
ZONE tundra and LISOTUNDRY. Tundra - Treeless expanses of arctic and subarctic zones - occupies the northern coast of the mainland and nearby islands. In harsh climate prevalent long congelation - The phenomenon that the surface is freeze and rocks to depth of 400 m contained ice. Frigidity stored for thousands of years. It roztaye summer only and only on the surface. The water had evaporated, and wintered layer does not infiltrate deep into her. So many summer tundra swamps. In a permafrost formed poor tundra-bog soils. They grow mosses, lichens, a few herbs (arctic poppy, different kinds of sedge) chaharnychky berries (blueberries, cranberries, holubyka). Somewhere happens dwarf birch and willow, which stelyutsya on the ground, pressed strong winds. Wildlife tundra poor. Lichens and fed sedge Reindeer and Caribou vivtsebyky - large animal with thick long hair that protects them from cold. Common wolf, polar fox, ermine, lemming. Birds are polar white owl and partridge.
Further south tundra turns into woodlands - Lisotundru, where in river valleys appear conifers.
Fig. Polar owl
Vivtsebyky - large herbivores, which are preserved in tundra with Ice Age. They live together droves and are reflected from wolves. Zahledivshy predator vivtsebyky not flee and take up a circular defense face with horns outside, gathered inside the calves. Wolves that attack, they reject the horns and trampling hoofs. However vivtsebyky were defenseless before the armed man who strongly exterminate them. Now these animals protected.
Fig. Natural areas of North America
Working with map
1. Which of natural areas extending in latitude direction and that - in the meridional direction?
2. Natural areas which had the belt most prevalent in North America?
3. Where is the arctic desert zone? As shaped by its natural conditions?
4. Where common area and semi- deserts?
5. Name your price prairies.
AREA HARDWOOD Forests. Coniferous temperate forests are called taiga. In severe winter snow and cool summer occur podzol soils. Disseminated permafrost, which causes considerable waterlogging territory. In American taiga growing up black and white spruce, fir, balsamic, American larch, a giant white cedar, pine of different kinds. With dribnolystyh common species birch, aspen, poplar.
Taiga fauna is much richer than in the tundra. Master the forest grizzly - American brown bear, which features a fierce tetchy, promptly and indefatigability in the persecution of the victim. Typical residents is a moose, wolf, lynx, fox, skunk, marten, mink, please, raccoon, beaver.
Fig. Moose. Alhonkin National Park, Canada
Zone of mixed forests. This zone is the transition of the taiga to wide-forest, because there along with many deciduous coniferous tree species. Especially common sugar maple, ash, elm, linden, beech, aspen, birch. Under warmer than in the taiga, temperate continental climate formed sod-podzol and gray forest soils. They rodyuchishi by taiga soils, including forests in this area greatly reduced, and the area occupied farmlands.
FOREST AREA platyphyllous. Zone located on the east continent south mixed forests. It is characterized by mild and moderate humid climate. On brown forest soils grow various kinds of oaks, maples, lindens, beeches. There sycamore, chestnut thermophilic and tulip tree, which flowers like tulips. This zone live wapiti deer, black bear, American Black Bear, lynx, wolverine, marten, wolf, fox, skunk, otter, the only marsupial species - possum. Now platyphyllous forests consolidated under arable.
Fig. Autumn forest. Canada
ZONE-steppe and steppe. This zone in North America called prairie. Forest occupies an intermediate zone between forests and steppes. They do not extend from west to east and from north to south. There common gray forest soils and ashed black. In forest areas grow mostly aspen and birch, and reigns in the desert lush variety of herbs and cereals.
Steppes – flat spaces covered with grassy vegetation - stretched from north to south in the center mainland. There is little snowfall cold winters and hot summers, often droughts, dust storms are accompanied. Vegetation dominated undersized grass: feather grass, bearded, tonkonih, bizonova grass. In the grassy vegetation formed fertile blackand chestnut soil. This was reflected on the animal world. Almost extinct bison, coyote was less (steppe wolves), foxes. Numerous unless rodents - marmots, ground squirrels, mice, dogs meadow. Since reptiles are the rattlesnake, viper. Prairie - Agriculture is the main strip, so natural vegetation there everywhere changed.
Fig. Buffalo preserved only in national parks
ZONE semi-desert. In North American semi-desert and a temperate, subtropical and tropical zones and do not form a continuous strip. Some appeared on the coast Pacific, the other - on the inner plateau and highlands in the so-called rainy shadow of the Cordillera. So one of the driest deserts and nayzharkishyh World eloquent name Death Valley formed in a small room, but mizhhirniy deep depression (-85 m).
The climate is arid desert. On gray-brown soils growing low bush - black sagebrush. At low sites dominates Loboda, forming cushions, under which better kept wet. Common salt-marshes, which can grow only soup and tamarisk. Sometimes Sal'ne endemic tree - globular spiny shrub with dark green leaves that vylyskuye as if lubricated with fat.
In the desert areas of common Mexican Highlands cacti, yucca, agave. With many animals especially rodents (hamster, ferret, rabbit) and reptiles (lizards, rattlesnake). There are antelope, pronghorn, coyote, cougar.
Fig. America - the birthplace of cacti
Fig. Evening in the desert. Arizona, USA
On South, where a drought common evergreen shrubs and growth. Large areas of Shrubs fired clay and replaced by fruit gardens.
ZONE monsoon and AC-humid forests. Monsoon forests of mixed grow on Prymeksykanskiy and Pryatlantychniy plains and peninsula Florida. The climate there is subtropical monsoon with high rainfall. Forests on zhovtozemah and chervonozemah grow many species of pines (turpentine, korotkohvoyna, marsh, lake, Caribbean), with hardwood - oak, tulip tree, magnolia. In marshy ground rules cypress marsh. The forests are inhabited baribal, lynx, opossum, near the water - otter, muskrat, raccoon. In southern there are large turtles and crocodiles, alligators.
This variable-humid forests occupy the southern part of the continent - the whole Central America isthmus. They have multiple layers grow as evergreen trees and deciduous that shed leaves in dry season. Among them, Ceiba, Brazilian wood, balsa. Soils - red. In fauna is dominated by representatives of South American forests: jaguar, tapir, armadillo, monkeys shyrokonosi with birds - toucans.
Today, forests are cut down severely, in their place lie Plantation cotton, tobacco, sugar cane.
Fig. Blue Heron
AREA HIGH RISE POYASNOSTI. You already know that the number of high-altitude zones and their features depend on the height of mountains and their position in the a given geographical area. In the Cordillera within the arctic, subarctic and temperate climatic zones due to a low position of the snow line, explain altitude vegetation are poorly developed. Thick coniferous forests cover the lower parts of mountains to a height of 1000-1500 m above placed mountain tundra, which alter the eternal snows and glaciers. However, in subtropical Cordillera upper limit of coniferous forests is at an altitude of 3500 m and above placed sub-alpine and alpine meadows.
Fig. Mountain goat. Colorado, USA
Wildlife Management. Economic human activities impact on all components of nature. Particularly affected soils, vegetation and fauna. Cities and ways to take more and more space. Active transformation of nature leads to increased frequency Natural disasters - Dust storms, floods, forest fires.
In North America passed laws aimed on nature conservation, renewable forests are cleared of contamination of the lake. On mainland and numerous nature reserves and national parks. In the largest America нatsionalnomu Park Wood Baffolo, that placed in the north of the mainland, most protected bison herd. The oldest Yosemite National Park, Founded in 1864, protected by huge forests are thousands of years Sequoias, waterfalls and a diverse fauna.
Questions and Tasks
1. What are the features placement of natural areas in North America?
2. What kind of natural areas in North America is not in South America?
3. Why flora and fauna Arctic deserts of the world poor?
4. What is called tundra? What natural features of this zone?
5. Describe the taiga zone.
1. How different from the mixed forest platyphyllous?
2. What measures are carried out for health nature on the mainland? K5