Olsen Phosphorus

The data originate from the long-term Exhaustion Land field trial at Rothamsted Research, which examines the relationship between crop yield and soil fertilizer inputs. In 1986, the yields of spring barley (variate Yield) were recorded from 20 plots. For each plot, the available soil phosphorus content was also measured using the Olsen P method (variate OlsenP). This dataset allows for the analysis of how variations in soil phosphorus levels influence barley yield under field conditions.

Usage

phosphorus

Format

A data frame with 3 variables: DPlot, OlsenP, Yield.

DPlot

Factor. Unique identifier for each field plot.

OlsenP

Numeric. Available soil phosphorus content measured as Olsen P (mg/kg or ppm).

Yield

Numeric. Yield of spring barley from each plot (typically in tonnes per hectare, t/ha).

Source

Welham, S. J., Gezan, S. A., Clark, S. J., and Mead, A. (2015) Statistical Methods in Biology: Design and analysis of experiments and regression

Examples

lm(Yield ~ log10(OlsenP), data = phosphorus)
#> 
#> Call:
#> lm(formula = Yield ~ log10(OlsenP), data = phosphorus)
#> 
#> Coefficients:
#>   (Intercept)  log10(OlsenP)  
#>         1.674          2.644  
#>