气化渣改良风沙土对土壤水分物理性质的影响

为了探讨气化渣对毛乌素沙漠风沙土的改良效果,利用气化渣作为一种风沙土改良材料,与风沙土按不同掺入量混合,通过对土壤粒径组成、保水性能以及土壤水分特征曲线的变化情况分析,探讨了气化渣对风沙土土壤水分物理性质的影响。结果表明:添加气化渣使风沙土的粒径组成得到明显改善,砂粒含量降低5.89%～35.8%,黏粒、粉粒含量分别提高0.89%～2.92%,7.94%～32.88%,风沙土土壤容重显著降低(p<0.05),降低幅度为7.75%～55.5%; 风沙土土壤质地也由砂土转向砂质壤土,保水性能也随之呈现上升的趋势,显著影响了土壤饱和含水量、毛管持水量和田间持水量(p<0.05),增长幅度分别为13.53%～158.93%,7.12%～126.95%,23.19%～252.47%; Van Genuchten模型可以很好地拟合气化渣添加后风沙土的土壤水分特征曲线,表明气化渣的添加明显提高了土壤保水性,并且风沙土土壤保水性能的主成分分析结果表明气化渣添加量越高土壤保水性提高越明显。由此可以得出,水煤浆气化渣能够有效地改善风沙土的水分物理性质,显著提高风沙土的保水性能,对风沙土改良效果明显。

Effect of Aeolian Sandy Soil Improved by Gasification Slag on Soil Water Physical Properties

In order to explore the effect of gasification slag on the aeolian sandy soil of the Mu Us Desert,the effects of mixture of the aeolian sand soil with different amounts of the gasification slag used as a kind of aeolian sand soil improvement material on the soil moisture physical properties of aeolian sandy soil were examined through analyzing of the changes in the particle size composition,water retention performance and moisture characteristic curve of the aeolian sand soil mixed with the gasification slag.The results show that the addition of gasification slag can significantly improve the particle size composition of the aeolian sandy soil;the sand content is reduced by 5.89%~35.8%,and the content of clay and silt particles are increased by 0.89%~2.92%and 7.94%~32.88%,respectively,which the aeolian sand soil bulk density significantly reduces(p<0.05),the decrease range is 7.75%~55.5%;the soil texture of aeolian sandy soil has also changed from sandy soil to sandy loam,and the water retention performance also shows an upward trend,which significantly affects the saturated water content of the soil and the capillary water holding capacity and field water holding capacity(p<0.05),the increase rates are 13.53%~158.93%,7.12%~126.95%,23.19%~252.47%,respectively;Van Genuchten model can well fit the aeolian sandy soil after adding gasification slag;the soil moisture characteristic curve shows that the addition of gasification slag significantly improves soil water retention,and the principal component analysis results of the soil water retention performance of aeolian sandy soil indicate that the higher the addition of gasification slag is,the more obvious the improvement of soil water retention is.It can be concluded that the coal water slurry gasification slag can effectively improve the water physical properties of the aeolian sandy soil,significantly improve the water retention performance of the aeolian sandy soil,and have a significant effect on the improvement of the aeolian sandy soil.