Abstract:A pot experiment was conducted to study the influence of different fertilization treatments on soil organic carbon(SOC), active organic carbon(AOC) and carbon pool management index(CPMI). The experiment included five treatments: CK(neither urea nor chicken manure was applied), N100(100% of nitrogen was provided by urea), M10N90(10% and 90% of nitrogen was provided by chicken manure and urea, respectively), M30N70(30% and 70% of nitrogen was provided by chicken manure and urea, respectively), and M50N50(50% and 50% of nitrogen was provided by chicken manure and urea, respectively). The results showed that the SOC contents under M30N70 and M50N50 treatments increased by 8.11% and 14.64% in comparison with the N100 treatment, respectively. The AOC content and CPMI achieved the highest value under M30N70 treatment and had significant differences with other treatments, showing 47.36%, 14.93% and 7.14% increases in AOC content and 65.49, 26.74 and 20.22 increases in CPMI, respectively, compared to the treatments of N100, M10N90 and M50N50. At the same time, M30N70 treatment had the maximum increase in the growth of poplar seedlings. The content of soil AOC was significantly positively correlated with the content of SOC, ground diameter and height of poplar seedlings, while was extremely significantly positively correlated with CPMI. Furthermore, the CPMI had significantly positive correlation with ground diameter and height of poplar seedlings, which would be a good index to assess influence of fertilization practice on soil quality. In conclusion, the different proportions of chicken manure co-applied with inorganic fertilizer had a significant influence on organic carbon, active organic carbon, CPMI and the growth of poplar seedlings, especially M30N70 treatment, which achieved the best effects among all the treatments and was the best proportion of chicken manure and inorganic fertilizer.