| A | B |
|---|
| delta | a flat plan created by sediment dropped at the river's mouth |
| drought | long periods without rain |
| erosion | wearing away and moving particles of soil and rock |
| filtration | to remove small particles from water |
| fresh water | water without any salt |
| geologist | scientist who studies landforms |
| glacier | large slow moving masses of ice |
| gravel | large pieces of rocks and minerals |
| humus | decayed organic material, also called loam |
| hydrologist | scientist who study the properties and movemenmt of water on and below the earth's surface and in the atmosphere |
| landform | types of natural features in the earth's surface |
| loam | humus |
| mouth | the point at which water from a river or stream empties into a larger body of water |
| organic matter | living and decayed plant and animal material |
| rivulets | a small stream or brook |
| runoff | water that flows over the surface of the land |
| sedimentation | depositing particles of rock and soil |
| soil | the uppermost layer of the land where plants grow |
| source | the beginning of a stream or river |
| springs | underground water that finds its way to the surface of the earth |
| surface water | water on the surface of the earth such as lakes, rivers, and streams |
| tributaries | small streams that flow into a larger stream or river |
| velocity | speed of motion |
| waste water | used water that goes down the drain to be cleaned |
| weathering | rocks breaking down into various earth materials |
| four parts of the water cycle | evaporation, condensation, precipitation, collection |
| sand | smaller than gravel, mostly quartz |
| clay | smallest particle size of soil |
| mountains | highly, steeply sloped and uplifted areas of rock on earth |
| plateaus | high but level areas, often next to mountains |
| plains | ares of flat land |
| energy | produced from movement of water molecules |
| water vapor | water in the form of gas |
| evaporation | the change of water from a liquid to a gas |
| condensation | to change from a gas to a liquid |
| clouds | tiny droplets of water or ice in the atmosphere |
| precipitation | rain, sleet, snow, and hail |
| drought | long periods without rain |
| weathering | rocks breaking down in various earth materials |
| inorganic matter | weather rock fragments |
| the three characteristics of soil: | appearance, texture, size of particles |
| silt | particles of soil suspended in water |
| pore space | spaces between the soil particles |
| zone of saturation | all the pores filled with water |
| zone of aeration | pores contain water and air |
| water table | the boundary between the two zones |
| soil compaction | soil particles packed together |
| aquifers | layers of sand, gravel, and other earth materials that water seeps through |
| head | the beginning of a stream or river where runoff has cut a channel |
| valley | a long low area carved by a stream or glacier with higher areas on both sides |
| canyon | a deep, steep-walled gorge carved in rock by a stream or glacier |
| drainage basin | all of the land drained by a river and its tributaries |
| tributary | a stream that flows into a larger stream or river |
| stream channel | the course along which water moves |
| flood plains | a flat area next to the stream and made up of loose sediment such as silt |
| main stem or trunk | a large stream or river which is the principal channel in a river system |
| water shed or drainage basin | the surrounding area drained by a trunk and its tributaries |
| dendrite | drainage pattern which forms when streams flow over gently sloped land |
| flow | amount of water that passes a given point in a given amount of time |
| meanders | large sweeping curves in the rivcerbank |
| flood | when a stream or river overflows or leaves its banks |
| flash flood | sudden increases in runoff |
| flood stage | water level at which a river overflows its banks |
| levees | high ridges along the banks of streams that prevent or minimize flooding |
| natural levee | deposits from flooding that gradually grow higher and protects the area from flooding |
| artificial levee | created by humans to provide added protection from flooding |
| flood control dam | a barrier that controls the direction and flow of the water |
| reservoir | an artificial lake that forms behind a dam |
| hydroelectric power | electricity generated by stored water |
