The long-term performance of composited soil with feldspathic sandstone amendment on sandy soil and its effects on corn yield

To estimate the long-term performance and the optimal ratio of feldspathic sandstone with sandy soil, experiments with different ratios of feldspathic sandstone to sandy soil (0:1, 1:1, 1:2 and 1:5 v/v) was conducted. The physical properties as soil texture, water-stable aggregate (WR0.25) content, and the organic carbon content of the composited soil for 6 years, and corn yield for 9 years were determined. Our results showed that after the addition of feldspathic sandstone: (1) soil texture was notably improved, changing from sand loamy soil (1:2 and 1:5) to sand loam soil (1:1) and silt sand soil (1:1) over planting time; (2) content of water-stable aggregate (WR0.25) significantly increased: WR0.25 of treatments 1:1, 1:2 and 1:5 all increased (by 29.26, 31.47 and 11.56%, respectively) compared with that of treatment 0:1; (3) the organic carbon content of the composited soils increased with time in all treatments. After six years of planting, average organic carbon content in treatments 1:1, 1:2 and 1:5 were 1.64, 1.51 and 1.77 g/kg, respectively, which were higher than that of 0:1 treatment; and (4) among the three ratios, treatment 1:2 (12 984 kg/ha) had the highest corn yield, followed by treatment 1:1 (12 040 kg/ha) and 1:5 (11 301 kg/ha). In conclusion, with a good performance, 1:2 was the best ratio of feldspathic sandstone to sand in improving the sandy soil structure of the Mu Us Desert, China.