Author : Nadelhoffer, K. J. Emmett, B. A. Gundersen, P. Kjonaas, O. J. Koopmans, C. J. Schleppi, P. Tietema, A. Wright, R. F.
Year : 1999
Title : Nitrogen deposition makes a minor contribution to carbon sequestration in temperate forests
Journal : Nature
Comment : They used 15N-tracer studies in nine temperate forests. This set of experiments is unique in that tracers were applied to large plots (102-105 m2). Their results indicate that trees are not the primary sinks for nitrogen deposition in temperate forests. Within tree biomass, most tracers were recovered in leaves, fine roots, bark and twigs. The mean 15N recovery in wood was 3% of inputs. The remaining fractions of applied tracers were recovered in litter, forest floor and mineral soil. Thus, their results indicate that soil rather than tree biomass is the primary sink for NOy and NHx inputs to temperate forests.