River Glossary wordsThese are words you should remember:
BACTERIA Tiny organisms that can only be seen with a high-powered microscope. Many bacteria are very good for us and billions live inside us all of the time. But a few are harmful and if they get into the water supply they can cause illness and death. BASIN The land drained by a river and all of its tributaries. BRANCH Another word for tributary. CANYON A deep, steep-sided valley in an area with mostly dry weather. The sides are bare, but the sides of a canyon do not have to be vertical. The biggest canyon in the wold is the Grand Canyon. CHALK A soft form a limestone rock. Chalk has many tiny gaps in it which allow water to sink through the rock. (See the section on Water where you will find chalk called an aquifer). CHANNEL The 'slot' cut by a stream or river and in which it flows. CLIMATE The long term pattern of weather. Weather is what we get day to day, climate is what we get on average. Examples: the weather will be fine tomorrow; the climate has hot summers and cool winters. CONFLUENCE A meeting of two streams or rivers. CONSERVE To protect from damage or bring up to a better condition than we found it. It is not quite the same as returning something to its natural state. To make it natural would mean keeping people away and generally we can't so that, so we try to find ways of letting people and wild plants and animals live together. DAM An artificial barrier put up to block the flow of a river. The lake that builds up behind the dam is called a reservoir. Dams can help to stop floods, give electric power and store water in case of drought. DELTA The material that builds up at the mouth of some rivers where they enter a lake or the sea. Deltas are common if a river carried a huge load of mud and sand to the sea. The material arrives faster than the sea waves can wash it away. DEVELOPING COUNTRIES Countries that are still relatively poor and which cannot yet provide such things as safe drinking water to all of their people. DISSOLVE When some liquids touch some solids, some of the surface of the rock goes into the liquid. This is called dissolving. The particles are so small they are invisible and so the liquid appears clear. EVAPORATE The way that liquid water turns to moisture and becomes part of the air. Moisture is invisible.
FILTER BEDS Tanks of sand, gravel and sometimes charcoal chips that filter out the bits of muck in river water and so help to make it look clean. They will also trap some bacteria and chemicals. FLASH FLOOD A flood caused by a sudden very heavy rainstorm. FLOOD When a river is carrying so much water that it cannot be held in the river channel. The extra water then spills over the land on either side to form a shallow lake. The lake, which usually lasts for a few days, is called a flood. FLOODPLAIN The nearly flat strip of land that occurs either side of a river as it flows in a lowland landscape. The floodplain; is made of mud and sand dropped by the river at the end of each flood. GENERATOR A machine for producing electricity. The generator is like an electric motor working in reverse, so instead of using up electricity, it produces it. GORGE A vertical slot cut by a river into a mountain landscape. The UK has many gorges, such as on the R Wye near Monmouth; on the R Lyd, near Okehampton; on the R Clyde, near New Lanark; on the R Avon, near Bristol. HEP Short for Hydro-electric power. Hydro means water, so this is power obtained by changing the energy of moving water into electric energy. This is done by ponding water behind a dam, then letting the water flow through pipes in the dam and onto the blades of a special electricity-producer called a turbine. HOLLOW A natural shallow bowl shape in a hillside. Hollows are usually the places to look for springs. They are usually the source of a stream, and best seen in wet weather. IRRIGATION The supply of water to plants in farmer's fields. Watering the plants in your garden is a sort of irrigation, but on a very small scale. In dry countries, farmers may use more water than all other uses put together. LAKE Any body of still water. A small lake is called a pond. LEVEE A long natural bank formed by the river during a flood. Levees are not all that common. They tend to form beside rivers carrying lots of sand because sand can only be carried by very fast-moving water and as soon as a river spills over its banks during a flood, the speed slows down and the sand is dropped. LIMESTONE A hard grey-coloured rock that is slowly dissolved by rain and stream water, allowing natural cracks to be widened. LIP The top edge of a waterfall. The place from where the water drops. MEANDER Natural twists and turns of a river as it flows over its floodplain. MOISTURE Water in the air. Water is made of such tiny particles in the air that it is invisible. MOUTH The end of the river, usually where it enters the sea. Some rivers enter lakes and then the river mouth is the place where it enters the lake. The mouth of a river may be marked by a delta. MUD The finest kind of material that a river makes. It is so fine it stays suspended in the water unless the water becomes still. It is what makes the river look cloudy. Mud particles are too fine to be seen. OXBOW A meander that has nearly double back on itself so that all that separates two parts of the river is a narrow neck of land. When this narrow neck of land is cut through, the meander loop forms an oxbow lake. PLUNGE POOL The deep pool that occurs below the lip of a waterfall. It is formed by the stones dropping down with the water from the lip high above. POLLUTE To introduce harmful substances into the water. These are usually chemicals. Some are let into the water from factories, but also chemicals used on farmer's fields and even our gardens can seep down through the soil and pollute river water. POTHOLE A shallow shaft made by stones going round and round on the same spot until they wear away the rock of a mountain stream or river. RESERVOIR An artificial lake that forms above a dam. Some reservoirs are very large and they are often called lakes, but you should not confuse them with a geographer's lake, which is a naturally ponded body of water. RESORT A place where people go to have a holiday and enjoy themselves. It usually contains just hotels, entertainments and shops. RIVER A large natural channel carrying water. usually more than tens of metres wide, and in the case of the Amazon, the world's biggest river, hundreds of kilometres wide near its mouth. SAND A fine material caused by small pieces being chipped off stones and the rock of a river bed as other stones bump into them. Sand is very fine, but you can still see each grain. SOURCE The place where a stream begins. This is usually in a hillside hollow. SPRING A natural flow of water from the ground. STREAM A small natural channel carrying water. Other names for stream are brook, burn and creek. There is no hard and fast rule about when a stream becomes big enough to be called a river, but most streams are just a few metres wide, whereas rivers are tens of metres wide or much more. TIDAL A part of the river close to the sea that changes height each day with the changes in sea level. TRIBUTARY A stream or river that flows to a larger stream or river. Other words for tributary are branch and fork. V-SHAPED VALLEY A valley that has steep, straight sides from the top of the valley to the river's edge. V-shaped valleys do not have flood plains. WATER CYCLE The way that water is continually moving from the oceans to the air, then forming into clouds, then producing rain which falls, goes through soil and rocks and flows back to the sea. WATERFALL A sharp break in the course of a river. This is often caused by a level band of hard rock that the river cannot easily cut through. The band of rock creates the lip that juts out at the top of the waterfall. WHITE WATER Water that is moving so fast, it traps air bubbles. It is the air that makes the water look white. Waterfalls, rapids and fast-flowing mountain streams and rivers all have white water. |