Challenges to Understanding Fluid Behavior in Plant Growth Media Under Microgravity

Fluid management in plant growth media under reduced gravity remains a challenge hindering integration of this critical component of advanced life support. A recent NASA-funded project diagnosed causes for limited progress in control of water and air in the root zone. Small finite volumes of porous media are used for plant growth in microgravity. Difficulties controlling water and air in the root zone likely result from an incomplete understanding of the system in 1g that is compounded by changes in water and air distribution due to microgravity. Key areas for future progress include engineered plant growth media for reduced gravity, improvements in sensing technology and better understanding of rhizosphere processes.