Effect of compaction under different levels of moisture on physical properties of soil and yield of sugar beet (Beta vulgaris L.) in AL-Ghab Regions

The study has shown that the apparent bulk density of soil increases with the increase of compression and moisture during press. The maximum rate of increase in depth was 0 – 20 cm that amounted 0.38g/cm3 at compression by 257.44-kilopascal and moisture average at compression by 19.03% (equal to 60% of the field capacity average of the soil) in comparison with the non-existence of compression. In addition, the size of the pores bigger than 50 microns decreased at the same above compression and above moisture in depth of zero – 20 cm by 20.20%. The size of pores bigger than 10 microns decreased by 20.65% in comparison with the non-existence of compression. While it was noted that the the maximum loss of root yield that amounted 17.52%, at compression by 257.44 kilopascal, and moisture 19.03%.