The soil nitrogen after applying different fertilizer doses
Usage
data(nitrogen)
Arguments
Format
A data frame containing 24 observations with the following 3 variables.
Fert
the fertilizer dose, in kilograms of nitrogen per hectare; a numeric vector
SoilN
the soil nitrogen, in kilograms of nitrogen per hectare; a numeric vector
Source
the fertilizer source:
a factor with levels 0 (inorganic) and 1 (organic; farmyard manure)
Details
The data give the soil inorganic nitrogen content
for various fertilizer doses,
including a control.
One application is from an organic source.
Each level of fertilizer has data from three replications.
References
Glendining, M.J., Poulton, P.R. & Powlson, D.S. (1992)
The relationship between inorganic N in soil and the rate of fertilizer N applied
on the Broadbalk Wheat Experiment.
Aspects of Applied Biology, 30, 95--102.