Open AccessA Laboratory Device for Continual Measurement of Water Retention and Shrink/Swell Properties during Drying/Wetting Cycles
Author(s) -
Pierre Boivin,
Sylvain Charpentier,
JeanCharles Michel,
G. F. Qi
Publication year - 2011
Publication title -
hortscience
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.518
H-Index - 90
eISSN - 2327-9834
pISSN - 0018-5345
DOI - 10.21273/hortsci.46.9.1298
Subject(s) - swell , water retention , wetting , hysteresis , water content , inflection point , materials science , intensity (physics) , water retention curve , chemistry , soil science , soil water , environmental science , composite material , geotechnical engineering , geology , mathematics , oceanography , physics , geometry , quantum mechanics
The precise measurement of the water retention and shrink/swell properties of growing media or soil over time is important for the effective management of irrigation and fertilization. A new apparatus was developed for simultaneously and continuously measuring the water retention and shrink/swell properties of growing media during several drying/wetting cycles with varying intensities (0↔–5 kPa, 0↔–10 kPa, 0↔–32 kPa). The measurements on slightly decomposed Sphagnum peat showed encouraging results. Regardless of the intensity of drying, water retention and shrink/swell properties are mainly modified after the first drying process, resulting in degradation of density and water retention, whereas these properties are unaffected by the other cycles, even if hysteresis phenomena are always shown to take place. Variations in drying intensity reveal different physical behaviors with an inflection point observed (i.e., a change in physical behavior) for the shrink/swell and water retention curves for the highest intensity tested (from –20 kPa).