Fig. 4: Relationships between potential denitrification activity and its best predictors across European arable soils.
From: Diverse crop rotations offset yield-scaled nitrogen losses via denitrification
Predictor variables selected by VSURF among a soil properties, b microbial biomass, c microbial community composition, and d abundances of nitrogen-cycling genes were used to generate accumulated local effects plots. They show the differences in prediction of denitrification rates compared to the mean prediction along the range of each predictor (x-axis), while accounting for potential correlations amongst predictor values. The effect is centered so that the mean effect is zero. The random forest model was built with 500 trees, 5 features considered at each split and a tree depth set to 6 (variance explained: 75 %, root mean square error: 69.9).
