Estimated nitrogen concentrations in humus based on initial nitrogen concentrations in foliar litter: a synthesis. XII. Long-term decomposition in a Scots pine forest

The final (limit) values for litter decomposition were estimated and, by ex trapolating a linear relationship between accumulated litter mass loss and litter N concentration, the N concentration at the limit value (N-limit) wa s estimated. The values for N-limit were compared with those of the A(01) l ayer (N-humus) and of newly shed litter (N-init). No difference was found b etween the A(01) and A(02) layers when their N concentrations were compared with the values for N-limit. There was a highly significant linear relatio nship between N-limit and N-init (R-2 = 0.769 and p < 0.001). Likewise, the re was a highly significant linear relationship between N-humus and N-init. When these two linear relationships were compared, there was no significan t difference in slope, while there was a significant difference in the inte rcepts of 6.76 and 7.25 mg,g(-1) for N-humus and N-init, respectively. Thus , for a given site in our investigation, the estimated value for N concentr ation in humus would be 6.8% lower than the measured one.