Dissolved organic nitrogen in contrasting agricultural ecosystems

The TDN pool was dominated by DON in less intensive agricultural systems. In relative contrast to DON, the amount of dissolved inorganic N (DIN) varied widely upon land use with intensive agricultural systems being dominated by NO3− and low input systems dominated by NH4+. We conclude that DON represents a significant N pool in all agroecosystems but its concentration is less sensitive to land use system than DIN.