Synthesizing bulk density for soils with abundant rock fragments Soil Science Society of America Journal, 58(2), 1994, pp 455–464

Bulk density is a fundamental soil property that is difficult to determine for gravelly to extremely gravelly soils because results vary significantly with sample volume. For such coarse soils, the representative volume (for whole-soil bulk density) should be large, but guidelines for selecting an appropriate sample volume do not exist.