Lysimeter
Encyclopedia
A lysimeter is a measuring device which can be used to measure the amount of actual evapotranspiration
which is released by plants, usually crops or trees. By recording the amount of precipitation that an area receives and the amount lost through the soil, the amount of water lost to evapotranspiration can be calculated.
Lysimeters are of two types: Weighing and non-weighing.
can be worked out by calculating the difference between the weight before and after the precipitation
input.
For trees, lysimeters can be expensive and are a poor representation of conditions outside of a laboratory
as it would be impossible to use a lysimeter to calculate the water balance for a whole forest. But for farm crops, it can represent field conditions well since it is done outside the laboratory. A weighing lysimeter, for example, reveals the amount of water crops use by constantly weighing a huge block of soil in a field to detect losses of soil moisture.
, a botanist from Massachusetts, built the first lysimeter in the United States.
Evapotranspiration
Evapotranspiration is a term used to describe the sum of evaporation and plant transpiration from the Earth's land surface to atmosphere. Evaporation accounts for the movement of water to the air from sources such as the soil, canopy interception, and waterbodies...
which is released by plants, usually crops or trees. By recording the amount of precipitation that an area receives and the amount lost through the soil, the amount of water lost to evapotranspiration can be calculated.
Lysimeters are of two types: Weighing and non-weighing.
Use
A lysimeter is most accurate when vegetation is grown in a large soil tank which allows the rainfall input and water lost through the soil to be easily calculated. The amount of water lost by evapotranspirationEvapotranspiration
Evapotranspiration is a term used to describe the sum of evaporation and plant transpiration from the Earth's land surface to atmosphere. Evaporation accounts for the movement of water to the air from sources such as the soil, canopy interception, and waterbodies...
can be worked out by calculating the difference between the weight before and after the precipitation
Precipitation (meteorology)
In meteorology, precipitation In meteorology, precipitation In meteorology, precipitation (also known as one of the classes of hydrometeors, which are atmospheric water phenomena is any product of the condensation of atmospheric water vapor that falls under gravity. The main forms of precipitation...
input.
For trees, lysimeters can be expensive and are a poor representation of conditions outside of a laboratory
Laboratory
A laboratory is a facility that provides controlled conditions in which scientific research, experiments, and measurement may be performed. The title of laboratory is also used for certain other facilities where the processes or equipment used are similar to those in scientific laboratories...
as it would be impossible to use a lysimeter to calculate the water balance for a whole forest. But for farm crops, it can represent field conditions well since it is done outside the laboratory. A weighing lysimeter, for example, reveals the amount of water crops use by constantly weighing a huge block of soil in a field to detect losses of soil moisture.
History
In 1875 Edward Lewis SturtevantEdward Lewis Sturtevant
Edward Lewis Sturtevant was an American agronomist and botanist who wrote Sturtevant's Edible Plants of the World....
, a botanist from Massachusetts, built the first lysimeter in the United States.