Freshwater - Drainage Basins

Endorheic Basin

basin that has no outlet to a sea or ocean

Exhorheic basin

drainage basin whose waters drain into the ocean or a larger lake

drainage basin

the area from which a single stream or river and its tributaries drains all of the water

watershed (drainage basin)

the (imaginary) boundary lines that separate one drainage basin from another

The hydrological cycle is defined as:

The natural cycle by which water moves between the biosphere, the atmosphere, the lithosphere and the hydrosphere (via a single input - precipitation and multiple outputs, 2 of which are evapotranspiration and run-off)

open system

a system in which exchanges of matter or energy occur across system boundaries

Input into the drainage basin

precipitation

output from a drainage basin (1 form)

evaporation

Factors that affect the rate of evaporation

temperature, humidity, wind speed, amount of vegetation coverage, surface albedo

Evapotranspiration (EVT)

The evaporation of water from soil plus the transpiration of water from plants.

Infiltration

the process by which water on the ground surface enters the soil

infiltration capacity

The maximum rate at which rain can be absorbed by a soil in a given condition

Factors affecting infiltration capacity

type of soil, vegetation coverage, duration of rainfall, pre-existing soil moisture, size of raindrops, and the angle of the slope of the ground

Inverse relationship between infiltration capacity and surface run-off

The greater the infiltration capacity of an area, the less surface run-off occurs and vice-versa

Overland flow (surface runoff)

water that flows over the land's surface - when precipitation exceeds infiltration rate AND when soils are saturated

Throughflow

Water flowing through the soil layer parallel (horizontally) to the surface

Base flow/groundwater flow

Slow moving water that seeps into a river channel - mostly constant

Percolation/Infiltration

the downward movement of water through pores and other spaces in soil and rocks due to gravity - water often follows percolines

Cryosphere (definition)

all solid ice in the form of glaciers, snowcaps, sea ice, permafrost, etc.

(cryo: ice)

Interception storage

The precipitation that falls on the vegetation surfaces (canopy) or human-made cover and is temporarily stored on these surfaces. Intercepted water either can be evaporated directly to the atmosphere, absorbed by the canopy surfaces or ultimately transmitted to the ground surface.

Throughfall and stemflow

Water dripping off leaves and down plant stems

Aquifer

A body of rock or sediment that stores groundwater and allows the flow of groundwater.

Groundwater

water held underground in the soil or in pores and crevices in rock - 96.5 % of all freshwater on Earth is stored in this form

recharge

the replenishment of an aquifer by the absorption of water (via percolation)

water table (groundwater table or GWT)

The upper level of the saturated zone of groundwater (or the upper level of an underground surface in which the soil or rocks are permanently saturated with water)