The Azimuth Project
Closed artificial ecosystem (Rev #1)


Closed artificial ecosystems are ecosystems, which are recreated in a laboratory.

Wikipedia contains some overview.

Wikipedia lists Biosphere 2, MELiSSA, and the BIOS-1, BIOS-2, and BIOS-3 projects.

Biosphere 2 is currently a research center of the University of Arizona. It hosted two important missions. Both missions had severe problems to regulate the O2 concentration. In particular bacteria in the soil were playing a major role in the debalance (from Wikipedia):

Many suspected the drop in oxygen was due to microbes in the soil. The soils were selected to have enough carbon to provide for the plants of the ecosystems to grow from infancy to maturity, a plant mass increase of perhaps 20 tons (18,000 kg).[25] The release rate of that soil carbon as carbon dioxide by respiration of soil microbes was an unknown that the Biosphere 2 experiment was designed to reveal.


The respiration rate was faster than the photosynthesis (possibly in part due to relatively low light penetration through the glazed structure) resulting in a slow decrease of oxygen. A mystery accompanied the oxygen decline: the corresponding increase in carbon dioxide did not appear. This concealed the underlying process until an investigation by Jeff Severinghaus and Wallace Broecker of Columbia University’s Lamont Doherty Earth Observatory using isotopic analysis showed that carbon dioxide was reacting with exposed concrete inside Biosphere 2 to form calcium carbonate, thereby sequestering both carbon and oxygen.[26]

citation [24], [25] and [26] is (unverified):

[24]^ Nelson, M, W. F. Dempster, N. Alvarez-Romo, T. MacCallum. 1994, Atmospheric Dynamics and bioregenerative technologies in a soil-based ecological life support system: Initial results from Biosphere 2. Advances in Space Research14 (11):417-426)

[25]^ Nelson and Dempster, 1996, op cit.

[26]^ Severinghaus, J.P. , W. Broecker, W. Dempster, T. MacCallum, and M. Wahlen. 1994. Oxygen Loss in Biosphere 2. EOS, Transactions of the American Geophysical Union, vol. 75, no. 3, pp. 33, 35-37

It would be very interesting to know what the methane concentrations were, finally it seems that especially wetlands emit methane (see eg this article)

again from Wikipedia:

Biosphere 2 contained representative biomes: a 1,900 square meter rainforest, an 850 square meter ocean with a coral reef, a 450 square meter mangrove wetlands, a 1,300 square meter savannah grassland, a 1,400 square meter fog desert, a 2,500 square meter agricultural system, a human habitat, and a below-ground infrastructure.

It looks as if all other projects had been terminated.

The last MELISSA news is from 2006. The ESA website for Melissa was edited last in 2009.

The last news from BIOS-3 seems to be from 2010. The last sentence on this website is:

В целом, 2010 год явился подготовительным этапом для дальнейших международных исследований по замкнутым экосистемам как с европейскими, так и китайскими партнерами.

(translation without guarantee: end of 2010 will show the preparation of further international investigations on closed ecosystems like with european and chinese partners)

BIOS-3 was run by the russian academy of science. Since the russian academy had been under pressure, this may be problematic for the project.

category: ecosystem