Spatial variability of soil physical parameters has long been observed, although this temporal effect is neglected in several studies and applications. The objectives of this research were therefore to better understand the effect of different agricultural land management practices on selected physical properties of an alluvial clay soil in the Mekong Delta and how these properties change with time. In a long-term experiment, plots were arranged in a randomized complete block design with four treatments and four replications: (1) rice?rice?rice (control ? conventional system as farmers? practice), (2) rice?maize?rice, (3) rice?mung bean?rice, and (4) rice?mung bean?maize. This study focuses on bulk density, soil porosity, matrix-porosity, macro-porosity and field saturated hydraulic conductivity. The soil samples were collected at three depths 0-10, 10-20 and 20-30 cm. Sampling and measurements were performed three times per season, i.e., 15 days after sowing (DAS), 45 DAS and 90 DAS (at harvest) for the winter-spring and summer-autumn seasons. Results show that bulk density, soil porosity, matrix-porosity and macro-porosity variation was mainly associated with treatments and soil depths. The rice monoculture showed a strong increase in bulk density, and a decrease in soil porosity, matrix-porosity and macro-porosity, with depth. This effect was smaller for the rotation of rice with upland crops. Rotating rice with two upland crops did not result in significantly different physical soil properties compared to a rotation with only one upland crop. Field saturated hydraulic conductivity showed great temporal variability, both seasonal and inter-seasonal. Seasonal variability was present for rice monoculture in both seasons, whereas inter-seasonal variability was most pronounced for rotations of rice with upland crops.  The strongest temporal variability was found for the rice with upland crop rotations during the summer-autumn season, with the variability being most pronounced during the first half of the growing season. Temporal variability of bulk density and matrix- and macro-porosity during both seasons is very limited for crop rotation treatments, whereas it was especially observed for rice monoculture treatment.