HIGHER-PLANTS IN A BIOLOGICAL LIFE-SUPPORT-SYSTEM FOR MAN

A model of human biological life support system (BLSS) was created wit h a photoautotrophic link including unicellular algae and higher plant s having an equal oxygen production. This system model supported the V ital activities of two people at the biomass regeneration of 92% from that consumed by them. The plant cultures studied were wheat grown on 11.25 m(2) (of a total 15 m(2)) and several vegetable species. The tot al photosynthetic productivity of the plants was high, stable over the studied time span, and independent on the composition of the system. However, the grain productivity of wheat decreased periodically, and d uring certain harvests it decreased to almost zero. A detailed analysi s revealed that this decrease was not caused by any of the system's ad jacent links as a similar decrease in yield was also found in the cont rol period with an autonomous growth of the plants in a closed volume of a chamber. Inclusion of higher plants into BLSS led to a considerab le improvement od food supply regeneration for man as compared to the previous model with only 26% regeneration effect. This inclusion did n ot exert any marked effect upon the general closure of the cycle. Howe ver, the biological value of the food for man was increased dramatical ly. This improvement is the main goal of designing and operating such BLSS systems.