Effects of Soil Type and Bulk Density on Determining Water Retention Curve by Centrifuge
In this study,Lou soil in Yangling and Mollisol in Nenjiang were selected,and four gradients of soil bulk density(1.0,1.1,1.2,1.3 g/cm3)were set,centrifuge and pressure plate methods were used to determine soil water retention curve(SWRC),and the van Genuchten(VG)model was used to fit SWRC.The results showed that with the increase of bulk density,the accuracy of centrifuge method gradually increased,and the accuracy of obtained parameter α of van Genuchten model increased by 38.46%-83.08%in Mollisol and 56.38%-95.70%in Lou soil.Centrifuge method had different performances in different suction sections,the measured value was lower near saturation suction(0-10 kPa),but higher in the high suction(10-1 500 kPa)with low accuracy,which was significantly(P<0.01)different with pressure plate method.In conclusion,centrifuge method is recommended to determine SWRC for soils with large bulk density and high organic matter content.
Soil water retention curvesSoil bulk densityCentrifuge methodPressure plate method
万方数据
维普
