The average NPP of the Pinus tabulaeformis forest in Badaling forest center is 3.14 t/hm~2-a,,and the arbor layer NPP is 2.58 t/hm~2-a, which made up 82.17% of the total biomass;

• 八达岭林场油松林NPP的平均值为3.；14t/hm~2·a；其中乔木层NPP平均值为2