Review outline of the second volume of seventh grade geography

Chapter IX Countries in the Western Hemisphere

Section 1 America (capital: Washington, the fourth largest city in the world)

I. Scope and location

1, continental United States+Alaska+Hawaiian Islands

2. Location: Latitude Location: continental United States-North temperate zone and subtropical zone, Alaska.

-frigid and sub-frigid, Hawaii-tropical. (The Tropic of Cancer passes through Hawaii and the Arctic Circle passes through Alaska, which is the only country in the world that passes through the three zones of heat, temperature and cold), located in the northern hemisphere and the western hemisphere;

Land and sea location: the United States is surrounded by the sea on three sides, the Atlantic Ocean in the east, the Pacific Ocean in the west, the Gulf of Mexico in the southeast, Canada in the north, Mexico in the southwest, Alaska in the Arctic Ocean and the Pacific Ocean, and Hawaii in the Pacific Ocean.

Second, the natural environment

1. Topography: It is divided into three longitudinal zones: the east: mountain-Appalachian mountains, the middle: plain-central plain, and the west: mountain-Rocky mountains and Cordillera mountains. Plains account for more than half of the total area.

2. Climate: mainly temperate continental climate; Precipitation decreases from east to west. (Affected by Gulf of Mexico and Atlantic Ocean) P84

3. Rivers and lakes: the largest river: Mississippi River (the fourth longest in the world) The largest freshwater lake group in the world: the Great Lakes (the largest freshwater lake in the world, Lake Superior, Lake Michigan and Lake America)

Third, the human environment.

1, population: over 300 million; Race: white, black, yellow (the cities with the largest number of overseas Chinese are San Francisco, Los Angeles and new york); Country: American country

2. Economy:

Agriculture:

(1) Agriculture: American agriculture has two characteristics: mechanization and specialization.

(2) Favorable conditions for agricultural development in the United States: ① Geographical location: the United States has a vast territory, most of which are located in temperate and subtropical zones, and Hawaii is located in the tropics, which is conducive to the development of agricultural production. The United States is surrounded by the sea on three sides and is influenced by the ocean. The climate is warm and humid, which is very beneficial to agricultural production.

(2) Topography: The United States is dominated by plains, which account for more than12 of the country's total area, and the cultivated land is vast, accounting for about 10% of the world's cultivated land. Fertile soil is conducive to agricultural development.

③ Climate: Good water conditions.

There are many rivers and lakes in America, and the Mississippi River is the fourth longest river in the world. It runs through the central part of the United States, with a large amount of water and a wide basin area. The Great Lakes are the largest freshwater lakes in the world. The Mississippi River and the Great Lakes provide good conditions for agricultural irrigation.

With superior natural conditions, the United States has vigorously developed agriculture and become a world agricultural power. The output and export volume of many products are among the highest in the world. (page 83)

(3) The relationship between the distribution of agricultural belts in the United States and topography and climate p85

industry

The most developed industrial country in the world. High-tech industries are developed.

Motor City-Detroit Silicon Valley-San Francisco

3. Resource-consuming country: The United States is the largest resource-consuming country and waste-emitting country in the world, and should bear the main responsibility for the sustainable development of world resources and environment.