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北美洲大部分地区属亚寒带和温带大陆性气候,整个大陆降水量丰富。这里有世界著名的大河——密西西比河,世界上有名的淡水湖群——五大湖(苏必利尔湖、休伦湖、密执安湖、伊利湖、安大略湖)。全洲河流年平均流量8,200立方公里。但是,由于气候和地形的影响,北美水文网的分布极不均匀,人烟稀少的北部地区有大量水剩余,而南方却水量不足,有的地区处于干旱和半干旱状态。位于北美洲中部的落基山脉一般海拔2,000—3,000米,南北延伸4,500公里,是北美最大的分水岭。北美的大川除圣劳伦斯河外,都发源于此。山地以东的河流流入大西洋的墨西哥湾或北冰洋,山地以西
Most of North America is sub-frigid and temperate continental climate, the continent is rich in precipitation. Here are the world famous river - the Mississippi River, the world famous freshwater lake - the Great Lakes (Lake Superior, Lake Huron, Lake Michigan, Lake Erie, Lake Ontario). The annual average flow of rivers in the whole continent is 8,200 cubic kilometers. However, due to the climatic and topographical effects, the distribution of North American hydrological networks is extremely uneven. There is a large amount of water remaining in the sparsely populated northern areas, while the water volume in the south is not sufficient. Some areas are in arid and semi-arid conditions. The Rockies, located in the central North America, are generally 2,000-3,000 meters above sea level and extend 4,500 kilometers north-south, making them the largest watershed in North America. Occidental North America in addition to St. Lawrence River, are originated from this. Rivers east of the mountains flow into the Atlantic Ocean in the Gulf of Mexico or the Arctic Ocean to the west of the mountains