Set 1
NORTH AMERICAN GRASSLANDS
1.In North America, native grasslands occur primarily in the Great Plains in the middle of the continent. The North American prairie biome is one of the most extensive grasslands in the world, extending from the edge of the Rocky Mountains in the west to the deciduous forest in the east, and from northern Mexico in the south to Canada in the north. Average annual rainfall ranges from about 40 cm (16 inches) in the west to 80 cm (31 inches) in the east. Average annual temperatures range between 10 degrees and 20 degrees Celsius (50 to 68 degrees Fahrenheit). In the moist regions of the North American grasslands, especially in the northern Great Plains, rainfall is distinctly seasonal, and temperatures can vary widely from very hot in summer to bitter cold in winter.
2.One hundred years ago, the Great Plains grasslands were one vast, unbroken prairie. Much of the prairie is now farmland, the m
A. Summer temperatures are very hot, while winter temperatures are very cold.
B. An unbroken prairie now extends from the western mountains to the eastern forest.
C. The original vegetation consisted of shortgrass, mixed grass, and tallgrass.
D. A large number of small wetlands are found throughout the region.
Set 1
NORTH AMERICAN GRASSLANDS
1.In North America, native grasslands occur primarily in the Great Plains in the middle of the continent. The North American prairie biome is one of the most extensive grasslands in the world, extending from the edge of the Rocky Mountains in the west to the deciduous forest in the east, and from northern Mexico in the south to Canada in the north. Average annual rainfall ranges from about 40 cm (16 inches) in the west to 80 cm (31 inches) in the east. Average annual temperatures range between 10 degrees and 20 degrees Celsius (50 to 68 degrees Fahrenheit). In the moist regions of the North American grasslands, especially in the northern Great Plains, rainfall is distinctly seasonal, and temperatures can vary widely from very hot in summer to bitter cold in winter.
2.One hundred years ago, the Great Plains grasslands were one vast, unbroken prairie. Much of the prairie is now farmland, the m
A. The average annual rainfall has risen and fallen several times.
B. Large parts of the prairie have been converted to agricultural use.
C. Melting glaciers have formed numerous depressions in the soil.
D. Scientists have transformed the region into one large carbon sink.
我来回答: