Table 4. Three techniques used to estimate the annual denitrification rate from the study site.

Technique	Correlation variable with D14	Spatial analysis	Modelling approach	Mean annual D14 rate (Gmol N yr−1 study site area−1)
1	None; used mean D14 for all stations	None; used study area as a whole	Propagated error	5.30±3.60
2	BPc for 51 stations	Empirical Bayesian kriging; 7 bins	Propagated error	4.65±0.16
3	BPc for 51 stations	Empirical Bayesian kriging; 7 bins	Randomly generated rates in each bin for 100,000 iterations	4.04±0.001