Ecology: Human carbon footprint leaves a lasting mark on forests

Human activities are having profound and overwhelming effects on the carbon balance of forests in the Northern Hemisphere. The finding has implications for forest management as well as our understanding of the global carbon and nitrogen cycles.
Human activities, such as agricultural fertilization and biomass burning, are pumping more nitrogen into the atmosphere, which in turn is having a positive effect on the growth of Northern Hemisphere forests, report Federico Magnani and colleagues. As the forests grow they lock away more carbon, so human activities are directly changing the dynamics of the carbon cycle, albeit in a complex and non-linear way.
The team’s study takes into account the many variables affecting carbon cycling, including rising temperatures and carbon dioxide levels, changes in land use, and plant photosynthesis and respiration. And the results show that mankind is ultimately controlling the carbon balance of temperate and boreal forests, either directly through forest management or indirectly through nitrogen deposition.
CONTACT
Federico Magnani (Universita di Bologna, Italy)
Tel: +39 051 209 6466; E-mail: federico.magnani@unibo.it

Peter Hogberg (Swedish University of Agricultural Sciences, Umea, Sweden) N&V author
Tel: +46 90 78 68 353; E-mail: Peter.Hogberg@sek.slu.se