A re-interpretation of the drainage moisture characteristic

I propose that the drainage moisture characteristic be separated into five stages, each covering a range of moisture potential. The relative pore size composition during each stage is considered and the implications in interpreting the experimentally derived relationship are discussed. The conclusion from this analysis is that the conventional methods of using either the slope at each matric potential, or of partitioning the moisture characteristic into potential steps to produce a pore size distribution are highly suspect. In particular, since the larger pores are underestimated and the effect of consolidation caused by change in matric potential has been misinterpreted, the conventional interpretation leads to error when used to derive other hydraulic properties or to describe the pore space occupied by soil inhabiting organisms.

► The drainage moisture characteristic has commonly been misinterpreted.
► The moisture characteristic is divided into seven drainage phases.
► Pores cannot drain unless they have access to air and water continuity to the drain.