Abstract:In experimental region, the runoff coefficient and soild runoff are only 0.074% and 0.902t/ha·a. The total amount of input nutrient from precipitation is 69.941 kg/ha·a, meanwhile the runoff output including soild runoff amounted to 29.143kg/ha·a, consequently the net increment in nutrient in this ecosystem made up 58.33% of the total input nutrient. In a certain period, the organic matter returned to the ecosystem is 985.35k/g ha·a, the loss of it from soil is 24.02kg/ha·a, thus the net increase of it will be about 41 times as much as the loss. The average utilization efficiency of radiant energy will be 4.64%. In a 5-year-old Cunninghamia lanceolata ecosystem, biomass and nutrient accumulation will amount to 51.6t/ha and 1078.704kg/ha respectively.