rivers

a drainage basin or river basin is an area of land drained by a river and it's tributaries. most of the rain that falls in the drainage basin will flow slowly down hill, either over the surface or through the top soil. eventually it will form a stream, which will gradually increase in size to eventually flow into a lake or the sea.

1. the source is where the river starts

2. tributary is a stream or small river that flows into a bigger one

3.confluence is where a small river joins a larger one

4.the mouth is where the river flows into the sea or lake

5.the water shed is the boundry of a drainage basin

the constant movment or transfere of water between sea land and atmosphere. also known as the water cycle.

1. percipitation the transfer of water from the air to the land. it can be rain, hail, sleet or snow

2. condensation the change of water vapor in the air into water droplets. these are visable as clouds

3. transperation the transfer of water from plants into the air as water vapor

4. evaporation the transfrer of water from the surface into the air as vapor

5. surface run off the transfer of water across the land and into the sea or lake

some of the water is also stored as ice, in small lakes and in the soil.

some water returns to the sea as ground water through soil and rocks.

inputs (enter the system)

percipitation - rain, hail, sleet or snow

storage (water held within the system)

interception - when water droplets collect on trees and plants

surface srorage - when water lies on the ground as puddles or lakes

soil moisture - water stored in the soil and broken rocks near the surface.

ground water - water stored in porus rocks deep below the ground

flows or transfers (movment of water)

surface runoff - water moving across the ground as a stream or river

throughflow - water flowing downhill through the soil

infiltration - when surface water soaks into the soil

percolation - water moving downwards through the soil into rocks below

groundwater flow - very slow water movement deep below the ground

outputs