Guest
Rivers and Lakes Many rivers start as a stream or spring, high up on a mountainside. As the water flows downhill, other streams flow into it to make a river. Waterfalls When a river flows over bands of soft and hard rock, it wears the soft rock away. This leaves a step of hard rock, which the river plunges over. This makes a waterfall. Stages of a river At first, a river flows very fast. It slows down as it reaches flat land, where it drops sand and mud that it has carried from the hills. Finally, the river flows into the sea. River transport For thousands of years, people have used rivers to carry people, animals and goods. Barges, steamboats, and canoes are different types of river transport. River Life Many amazing animals are suited to life in or near the world`s rivers. Piranhas are ferocious fish with razor-sharp teeth for snapping up their prey. Otters are rare animals with sleek, streamlined bodies for swimming. Crocodiles hide in the water, then leap out to grab their prey. Water boatmen are insects that use their legs to raw across the water. Salty lakes Some lakes are filled with salty water. The Dead Sea, between Israel and Jordan, is so salty that you can float in it and read a newspaper. The lake is called the Dead Sea because no fish can live there. Lakes A lake is a large stretch of water surrounded by land. It is made when rain or river water fills a large hollow or dip in the ground. Many lakes form high up in the mountains, where ice has carved out a hollow. The largest lakes The world`s biggest freshwater lake is Lake Superior in the USA and Canada. It is part of a group of five huge lakes, called the Great Lakes. Lake Life Lakes are home to hundreds of plants and animals. Huge flocks of brightly coloured flamingoes build their nests on the shores of some lakes in Africa. Flamingoes use their curved beaks to sieve lake water for food. Flamingoes get their pink colour from the food they eat.
