Land equivalent ratio


The land equivalent ratio is a concept in agriculture that describes the relative land area required under sole cropping to produce the same yield as under intercropping.

Definition

The FAO defines land equivalent ratio as:
For a scenario where a total of crops are intercropped, the land equivalent ratio LER can be calculated as
where is the number of different crops intercropped, is the yield for the crop under intercropping, and is the yield for the crop under a sole-crop regime on the same area.

Example calculation

The table in this section provides yield values for a hypothetical scenario intercropping a grain crop with a fruit tree crop.
The first two columns state the yields for intercropping and sole yields.
The third column, equivalent area, column calculates the area of sole cropping land required to achieve the same yield as 1 ha of intercropping, at the same management level.
The land equivalent ration can be calculated as
An interpretation of this result would be that a total of 1.4 ha of sole cropping area would be required to produce the same yields as 1 ha of the intercropped system.

Applications

The land equivalent ratio can be used whenever more than one type of yield can be obtained from the same area. This can be intercropping of annual crops or combination of annual and perennial crops e.g. in agroforestry systems.
It is also possible to calculate LERs for combinations of plant and non-plant yields, e.g. in agrivoltaic systems.
The table below lists some examples for land equivalent ratios published in scientific journals:
CropsCountry/regionLERSource
eggplant, jackfruitBangladesh2.17
cocoa, coconutMexico1.36
solar electricity, maizeItaly1.23 - 2.05
ginger, maize, soybeanNepal2.45
maize, cowpeaNepal1.58
millet, soybeanNepal1.40