Impact of long-term N deposition on nitrogen transformation and translocation in a northern peatland

• Applicant: Professor Dr. Christian Blodau (†)
• Subject Area: Hydrogeology, Hydrology, Limnology, Urban Water Management, Water Chemistry, Integrated Water Resources Management
• Term: from 2007 to 2010
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 43824071

Large areas of peatlands have been exposed to elevated atmospheric N deposition. When sustained chronic inputs of N lead to “nitrogen saturation”, N is lost from the soil, and environmental pollution will inevitably occur. Ombrotrophic, Sphagnum-dominated peatlands are exclusively fed by wet and dry atmospheric deposition and are very sensitive to increased atmospheric N input. It is thus of great scientific interest to examine the changes in N mass balances and cycling induced by anthropogenic N input. Little is currently known about the changes in the fate and mobility of N following chronic N pollution. The proposed project seeks to clarify the pathways of N transformations and N mobility in different pools under different long-term nutrient fertilization and changing plant cover through combined application of 15N as an isotopic tracer and HYDRUS modeling. The mechanisms of N retention by soil and plants will be elucidated and N saturation thresholds will be estimated by empirical analyses and modeling. Results from this study will improve our understanding of the fate of N under increasing N load, thereby enhance our ability to predict the future response of the N balance and cycle in northern peatlands.

• DFG Programme: Research Grants
• International Connection: Canada, USA
• Participating Persons: Professor Nathan Basiliko; Professorin Jill Bubier; Professor Dr. Jan Fleckenstein; Professor Dr. Tim Moore