Forests trapped in nitrogen limitation - an ecological market perspective on ectomycorrhizal symbiosis - Franklin, Oskar (International Institute for Applied Systems Analysis (Àustria)) ; Näsholm, Torgny (Swedish University of Agricultural Sciences. Department of Forest Ecology and Management) ; Högberg, Peter (Swedish University of Agricultural Sciences. Department of Forest Ecology and Management) ; Högberg, Mona N. (Swedish University of Agricultural Sciences. Department of Forest Ecology and Management)