Understanding the relationship between the soil ameliorants and soda salinized meadow soil is crucial for improving effect on different depth soil layer. The study investigates the effects of the soil ameliorants on the desalting of soda salinized meadow soil under flooding condition, we conducted a simulated leaching soil column experiment in laboratory, six ameliorants application levels, 0g, 0.01g, 0.05g, 0.10g, 0.50g, 1.0g with each soil column (cross-sectional area 0.0113 m2), equivalent to the 0 kg?hm-2, 8.85 kg?hm-2, 44.3 kg?hm-2, 88.5 kg?hm-2, 442.5 kg?hm-2, 885.1 kg?hm-2, defined as S0、S1、S2、S3、S4、S5 respectively. Our results indicated that under flooding condition, compared to S0, the application of soil ameliorants treatments (S3, S4 and S5) substantially reduced soil bulk density and soil pH on different depth soil layer (0~30cm), decreasing by 3.88% to 8.87% and 2.36% to 8.05%, respectively, and substantially increased soil porosity by 3.82% to 9.38% (P<0.05) on different depth soil layer (0~30cm), the application of soil ameliorants treatments(S2, S3, S4 and S5) enhanced soil moisture infiltration content of 20~40cm soil layer, with an increase of 55.9% to 294.6% (P<0.05), the application of soil ameliorants treatments reduced exchangeable sodium content with 0~10cm and 10~20cm soil layer (P<0.05), decreased by 4.84% to 56.5% (P<0.05), increased exchangeable sodium content of 20~30cm and 30~40cm soil layer by 1.09%~17.1%, S3, S4 and S5 reduced electrical conductivity of 0~10cm soil layer by 49.0% to 60.4% (P<0.05), increased electrical conductivity of 20~40cm soil layer by 3.68% to 19.8% (P<0.05), S2, S3, S4 and S5 reduced CO32- content of 10~20cm soil layer by 5.98% to 23.4% (P<0.05), S3, S4 and S5 reduced HCO3- content of 0~30cm soil layer by 1.49%~18.0%, S2, S3, S4 and S5 substantially enhanced ≥0.25mm water stable aggregate size, with an increase of 16.4% to 161.7% (P<0.05), S3, S4 and S5 substantially increased mean weight diameter (MDW) by 5.78% to 161.7% (P<0.05). Overall, comprehensive the effect of soil ameliorants on the desalting of soda salinized meadow soil and the application rates of Soil Ameliorants, the optimum application rate for the degree of soil salinization in this experiment is proposed as being 0.1g (88.5 kg/hm-2) with each soil column. |