retention property of the porous medium. A well-defined matrix can improve and stabilize
plant rooting environmental conditions by optimizing and controlling fluxes and content of
critical plant resources. The objectives of ORZS were to develop a modeling approach for
optimizing liquid and gas fluxes to plant roots under extreme volume constraints and reduced
gravity conditions. Secondly, this study aimed to extend this approach to design engineered
porous media to satisfy plant root metabolic requirements in reduced gravity. Media properties
in terms of hydraulic and structural constraints were combined with physiological information
(optimal oxygen concentration or water content) and used to express gas and liquid fluxes to
plant roots. Further efforts to engineer optimal porous medium properties should strike a
balance between the biological needs of the plants, practical limitations regarding material
properties (cost, weight, etc) and providing the desired transport properties (Jones 2005).
PUBLICATION(S)
Heinse R, Jones SB, Tuller M, Bingham GE, Podolsky IG, Or D. Providing optimal root-zone fluid
fluxes: Effects of hysteresis on capillary-dominated water distributions in reduced gravity. SAE
Technical Paper. July 12, 2009;2009- 01 -2360:10. doi: 10.4271/2009- 01 -2360.
Jones SB, Or D, Heinse R, Bingham GE. Modeling and design of optimal growth media from
plant-based gas and liquid fluxes. SAE Technical Paper. July 2005; 2005-01-2949. doi:
10.4271/2005-01-2949.
This investigation is complete; however additional results are pending publication.