Abstract:

It is important to determine the equilibrium of soil organic carbon content for the correct evaluation of the carbon sequestration potential and the reasonable distribution of organic matter under the fertilization condition.This article tried to analyze previous studies of organic carbon storage in Jiangxi Province,and used Jenny model to simulate dynamics of soil organic carbon under longterm fertilization condition.Results show that the soil organic carbon reserves in Poyang Lake ecological area account for 46% of the whole province,and the highest is in the Yingtan area,the lowest is in the Jiujiang area.Fertilization increased the contents of soil carbon significantly.The soil organic carbon contents of single application of organic or combined application of organic manure and chemical fertilizers (70F+30M,50F+50M,30F+70M,NPKM,NPK+straw,NPK+pig manure and NPK+ clover)treatments are higher than that of the application of chemical fertilizer treatment,in which 30F+70M of Nanchang County,OM of Jinxian County and NPK + pig manure of Yujiang County treatments were the highest.Compared with application of chemical fertilizers treatments,its organic carbon content at steady state and C sequestration potential of paddy soils were increased by 3061% and 6115%,3017% and 5496%,3826% and 7479%,respectively.Therefore,the combined application of organic manure and chemical fertilizers are the most effective application methods to improve soil organic carbon density and sequestration potential of paddy soils in Poyang Lake ecological area.Combined application of pig manure and chemical fertilizer is the best,and the ratio of 70% organic manure combined with 30% chemical fertilizers is the most suitable fertilization