Turnover of carbon and nitrogen in coniferous forest soils of different N-status and under different 15NH4-N application rate

abonos nitrogenados application rates azote biomasa biomass biomasse carbon carbon cycle carbone carbono ciclo del carbono coniferous forests cycle de l'azote cycle du carbone cycling dose d'application enfouissement enterrado forest soils humus immobilisation immobilization incorporation mor nitrification nitrogen nitrogen cycle nitrogen fertilizers pinus sylvestris soil organic matter soil types suelo forestal tipos de suelos type de sol