Runoff sediment concentration flows to the flood season during the ice age, and the climate flows through the whole country and into the ocean.

The Mekong River is large and small from north to south. June-June 10 Subtropical evergreen broad-leaved forest and tropical evergreen broad-leaved forest are called Lancang River, Thailand, Laos, Cambodia and South China Sea (the most important international rivers in Southeast Asia) in China.

The Ganges River is large and small from west to east. 6- 10 tropical monsoon India Nepal Bangladesh Bay of Bengal (the largest in India) Northern Hemisphere.

The Indus River is large and small from north to south. June-June 10 Alpine meadow, tropical monsoon and tropical desert are called Shiquan River in China and Arabian Sea in the northern hemisphere (the birthplace of world civilization).

Euphrates River and Tigris River from north to south11-April Mediterranean climate, tropical desert climate Turkey, Iraq, Kuwait Persian Gulf (birthplace of world civilization) Northern Hemisphere

The Nile is large and small from south to north. From June to September, tropical rain forest, savanna, tropical desert, Tanzania, Kenya, Ethiopia, Sudan, Egypt, Mediterranean (the longest in the world), northern hemisphere.

The Niger River is large and small, from west to east and then south. May-10, savanna, tropical desert, tropical rain forest, Nigeria, Niger, Burkina Faso, Gulf of Guinea, northern hemisphere.

The Congo River (the second largest in the world) has no savanna, rainforest, Tanzania, Congo gold, Congo cloth and the equator of the Gulf of Guinea in Angola all year round from east to west.

Zambezi River is large and small, from west to east, from June to September, savanna, Indian Ocean (the largest in the southern hemisphere) and southern hemisphere.

The Po River is very small, from west to east,11-April Mediterranean, Switzerland, France, Italy Mediterranean (Italian industrial center) Northern Hemisphere.

The Seine River is very small, and it is a uniform temperate ocean from east to west all year round. The French Atlantic (which flows through Paris) is in the northern hemisphere.

The Rhine River is very small and evenly distributed from southeast to northeast all year round. Switzerland, Germany, the Netherlands and Belgium North Sea (the largest freight volume in the world) are in the northern hemisphere.

The Thames is very small, and the temperate ocean is even all year round from west to east. The North Sea of England (which flows through London) is located in the northern hemisphere.

The Elbe River is very small, and the temperate ocean is even from south to north all year round. The North Sea of Germany (which flows through Berlin) is in the northern hemisphere.

The Danube is very small, and the temperate ocean is even all year round from west to east. Switzerland, Germany, Hungary, Romania, Bulgaria, Black Sea (the largest number of countries in the world), the northern hemisphere.

Volga River (inland river) is small, from north to south 1 1-2, with temperate continental climate from July to August, Russian Caspian Sea (the longest in Europe) and northern hemisphere.

Ob river11-April from south to north July to August temperate continental climate () China is called the Irtysh River, the Russian Arctic Ocean (with ice flood phenomenon), the northern hemisphere.

Yenisei River11-April from south to north July to August temperate continental climate (coniferous forest) Russian-Mongolian Arctic Ocean (with ice flood phenomenon) Northern Hemisphere

Lena River11-April from south to north July to August temperate continental climate (coniferous forest) Russian Arctic Ocean (with ice flood phenomenon) Northern Hemisphere

From June to September, there are temperate continents, temperate deserts and subtropical evergreen broad-leaved forests in the north and south of the Mississippi River.

The northern hemisphere of the Gulf of Mexico (the second largest basin).

The Amazon River is large and small (the largest in the world), with a year-round even alpine climate from west to east, tropical rain forests in Peru, Brazil and the equator of the Atlantic Ocean (the largest drainage area).