The N distribution and cycle in on Alpine Meadow Ecosystem by a compartment model was studied.The results showed that the N storage was 10 63t/hm 2,mainly existing as org. N in the soil pool.Although the total N was abundant,the available N was in deficiency.The N storage was 190 1±49 62kg/hm 2 in the plant sub system,and 79 26% of it stored in living roots.By estimating the N input and output amount in the Alpine Meadow Ecosystem,it appeared that the amount of N output(159 35kg/hm 2·a) was much m...