Fig. 3
The accuracy performance of the carbon-water flux simulation models (random forest model, RFM) at test flux stations. The NEE (net ecosystem carbon dioxide exchange) and WF (water flux) R2-based accuracy performance of the RFM of each split of the 10-time 10-fold cross-validation for (a) Overall with 156 stations, (b) Wetland with 16 stations, (c) Cropland with 23 stations, (d) Grassland with 47 stations and (e) Forest with 64 stations. The box plots show the R2 distribution of each flux station of the test set for different categories, in which the whiskers indicate the 1.5 times’ interquartile range.
