Land Equivalent Ratio (LER)

Evaluates the productivity advantage of intercropping systems over sole cropping.

land_equivalent_ratio(
  yield_inter_a,
  yield_sole_a,
  yield_inter_b,
  yield_sole_b,
  verbose = TRUE
)

Arguments

yield_inter_a

Numeric vector. Yield of crop A in intercrop (kg/ha).

yield_sole_a

Numeric vector. Yield of crop A in sole crop (kg/ha).

yield_inter_b

Numeric vector. Yield of crop B in intercrop (kg/ha).

yield_sole_b

Numeric vector. Yield of crop B in sole crop (kg/ha).

verbose

Logical. If TRUE, prints informational messages. Default TRUE.

Value

Numeric vector. LER values. Values greater than 1 indicate an intercropping advantage; less than 1 indicates a disadvantage.

Details

$$LER = \frac{Y_{iA}}{Y_{sA}} + \frac{Y_{iB}}{Y_{sB}}$$

References

Mead, R. & Willey, R.W. (1980). The concept of a land equivalent ratio and advantages in yields from intercropping. Experimental Agriculture, 16(3), 217-228. doi:10.1017/S0014479700010978

Examples

land_equivalent_ratio(yield_inter_a = 3500, yield_sole_a = 4500,
                      yield_inter_b = 800, yield_sole_b = 1200)
#> LER computed.
#> [1] 1.4444