Development of a Mechanistic Model to Predict the Influence of Gravity on Higher Plant Growth

Pr. Jean-Pierre FONTAINE

Co : Lucie POULET * , Claude-Gilles DUSSAP

Pascal Institute, Clermont Auvergne University, France.

* NASA Kennedy Space Center, Florida, USA.

Long-duration human space missions will need to develop an efficient life-support system to recycle atmosphere, water and waste for the crew survival. The European Space Agency MELiSSA project (Micro-Ecological Life Support System Alternative) mimics a lake ecosystem. It consists of a closed-loop bio-regenerative system based on microorganisms and higher plants and providing a circular cycling of mass, including O2 production, CO2 capture, water recycling and food production. As growth and development of higher plants are strongly influenced by the environmental conditions (g, p, T, RH, partial pressure of O2 or CO2), bio-regenerative life support systems require a high level of control and management. The goal of this study is to develop a mechanistic model to predict the effects of microgravity or of a reduced gravity environment on plant growth at its morphological, physicochemical and biochemical levels. Current agronomy plant growth models are not adapted for growth in controlled environments and do not provide a better understanding of physical growth mechanisms. Thus, a mechanistic plant growth model has been under development for the MELiSSA project for a few years. This study describes the addition of gravity as a parameter, taking into account the altered gas exchanges in low-g environments. The influence of convection intensity was investigated for several gravity levels. A recent use of parabolic flights, on a specifically designed set-up, has attempted to quantify plant gas exchange at the leaf level under forced convection based on IR measurements.

Biography

Pr. Jean-Pierre FONTAINE : Professor in chemical engineering at the University Clermont Auvergne (Clermont-Ferrand, France) since 2003.

Beforehand, he worked for 08 years in industry (R&D center in Sophia Antipolis, France), 02 years at the University of Colorado (Boulder, Colorado, USA) and 05 years at Aix-Marseille University (France), where he obtained his PhD in Fluid Dynamics in 1990.

His research activities have focused on the modelling of complex multi-physics transport phenomena (fluid, heat and mass transfer) in different domains. The main topics concern crystal growth, humidity sensing, condensation transfer on heterogeneous surface, interfacial phenomena, reduced gravity environments, dye sensitized solar cells, hydrodynamics of bioreactors in order to optimize mixing and biological reactions and the influence of gravity on higher plant growth.

He has authored more than 60 peer-reviewed publications, 06 European patents, and has contributed to about 80 conferences.