A multi-layers cultivation system using fluorescent lamps as a plant cultural system in the CELSS was proposed, and its performance, productivity, and power consumption were investigated throughout cultivation tests of lettuce and tomato.
Utilizing close illumination with fluorescent lamps, 3 layers of planting beds were vertically stacked for seedling cultivation and 2 layers for growth, and the compact cultivation system could be realized. The productivity of lettuce (75g/plants) by a multi-layers system was about 5 plants/m² (site-area) /day. The lighting power consumption and total power consumption for the production of lettuce (75g/ plant) was about 1.1 kwh/ plant and 2.5 kwh/ plant, respectively.
Thus, the lighting power consumption by close illumination was about half that of conventional high pressure sodium lamps. On the other hand, the power consumption for the production of a tomato fruit was about 2.5 kwh.

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A lighting design method of an experimental plant cultivation system equipped with fluorescent lamps set 30cm above the cultivation panel was proposed. The number of fluorescent lamps could be determined by using the coefficient of utilization (U), which indicates the light utilization efficiency in the cultivation room. When 42 fluorescent lamps (110w) were illuminated in the cultivation room, a high mean light intensity of about 45 klx was obtained. The value of U was found to be about 1.7; nearly 2.5 times higher than the value obtained by the illumination method using high pressure sodium lamps. Thus, the light utilization efficiency of the cultivation room could be greatly enchanced by the close illumination method using fluorescent lamps.

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The closed ecological experiment facility is used as a simulator for a CELSS and for the earth, in order to clarify the interaction between the ecological components, such as plant and human beings, and the gas balance. In this report, a closed ecological experiment was conducted with a closed small chamber (1.37m³in volume) in which lettuce plants and shiitake mushroom were cultivated. We monitored CO₂ and ethylene concentrations inside the chamber for 4 days and investigated the interactions between these gases and the biological components.
The CO₂ concentration inside the chamber depended on the combination of lettuce and shiitake mushroom, and varied from 190 to 5, 000 ppm. In each experiment CO₂ concentration changed with time, because the net photosynthetic rate of the lettuce and the respiration rate of the mushroom mycelium changed. The former changed with the increase in its leaf area and with the change in CO₂ concentration and the latter gradually decreased with time.
The concentration of ethylene, which was released from the lettuce and the mushroom, increased to 0.15 ppm at the end of the experiment. The visible injury was observed in the lettuce leaves, which might be due to the increased ethylene concentration. It is essential to identify and quantify trace contaminants including ethylene and to investigate the effects of trace contaminants on the growth of the lettuce and the mushroom.
From these results, the interactions between gas balance and the biological components in the closed chamber were clarified. Some of problems for the establishment of the closed ecological cultivation system were also pointed out.

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Because of the existence of biosphere, the earth's environment and biosphere have formed a self-developed system maintaining habitability for biota, which is called the geophysiological system or Gaia. Carbon isotope records in sedimentary rocks imply that the ancient earth was not abiotic but, rather, has been in a state of global biotic saturation since almost 4 Gyr ago and that microbial photoautotrophs must have been fully operative almost 4 Gyr. This reveals that our environment has been under the influence of life since its early stage. Biological removal of CO₂ from the atmosphere and production of O₂ through H₂ O-splitting photosynthesis have made a large difference of the earth's environment from the other lifeless planets'. Biosphere and the earth's environment have interdependently evolved as a holistic system just like a living system.
We argue a new theory on evolution of the earth's environment, which is constructed upon a new life-view that a living system forms a self-developed and self-organized system so as to be satisfied with the principle of existence against the external disturbances. Thus, geophysiological researches are most appropriate for studies about evolution of the earth's environment. Studies on closed ecosystem must play very important roles upon geophysiology, because the earth itself is forming a huge closed ecosystem. Then we performed experiments using a microcosmic type closed ecosystem to investigate the property of the living systems like as the earth.
Our experimental ecosystem has been maintained for more than 400 days. The kinetic of oxygen concentration change depends on the length of dark period. And we get hints at further studying about interrelationships between homeostasis organized in the ecosystem and an increase in oxygen concentration, or about the meaning of the existence of animals in the ecosystems.

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This report is a study on a food production system which is mainly for plant culturing with added purposes as oxygen production and animal breeding as a supplement to nutritive values of plant foods to be produced in CELSS.
As the result of the study, the following food production systems were chosen, namely, rice, wheat, potato, soybean, lettuce, etc., productions by means of hydroponic culturing with artificial light, and the milk production system by breeding goats to make use of inedible portion of the plants to be cultivated.

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To construct a life support system, two different approaches appear to have been taken. One stems from studies on microcosms and has been mainly performed in the field of environmental toxicology. The other is of pysico-chemical life support system typified by spacesuits.
Neither approach is yet to succeed in establishing a long-lasting, large-scale life support system, however. The one and only closed, ecological life support system of the kind existing today, i. e., the vivasphere (the integrated whole of the bioshpere and the humanosphere), has been made up of the close interactions between the physico-chemical and biological processes. As an example of such an interaction, the known history of the vivasphere has been presented, with special reference to the size of the biosphere during Precambrian period. The intimate interaction between the geological and biological processes existed in the period would indicate that the successful construction of the closed, ecological life support system might be realized when due respect is paid to both the physico-chemical and biological processes.

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