Composite samples of L/F/H horizons from Calluna moorland peaty podzol profiles, derived from granites or granitic tills, have been collected from all over Scotland on a 20-km grid basis. The sites were all in the altitude range 200–500 m with a slope from 5–45°. At low to moderate total N and NH4+ deposition (i.e. ≤ 9 and ≤ 4 kg ha−1 year−1, respectively), total soil N and soil C:N ratio increased almost linearly with atmospheric N deposition. The N accumulation appears to be related to N deposition and to the effect of acidification upon organic matter accumulation rate, with C accumulating relatively much faster than N, to increase the C:N ratio at sites with low to moderate N deposition. At total N or NH4+ deposition values > 9 and 4.0 kg ha−1 year−1, respectively, the C:N ratio declined with increasing N deposition.
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